Pineapple Production in Vanuatu

Pineapple Production in Vanuatu Trainers Guide

Aad Van Santen with Kyle Stice

Contents

Background 1 Introduction 2 Pineapple Planting Material 4 3.1 Varieties 4 3.2 Types of Planting Material 5 Site Selection 7 4.1 Land Requirements 7 4.2 Selection Criteria 7 Land Preparation 12 5.1 Bush Clearing 12 5.2 Pre-planting Weed Control 12 5.3 Ploughing and Final Soil Preparation 13 5.4 Preparation of planting beds 14 Field Cropping Layout 6.1 Sole Cropping 6.2 Integrated Vegetable Cropping 6.3 Perennial Integrated Cropping 6.4 Erosion control on the farm

15 15 17 19 21

Planting Pineapple 24 7.1 Collection of Planting Material 24 7.2 Storage of planting material 25 7.3 Grading 26 7.4 Time of planting 27 7.5 Method of Planting 28 7.6 Planting depth 29 7.7 Post Planting Treatment 30 7.8 Crop Rotation 31 Crop Nutrition 32 8.1 Overview 32 8.2 Nutrient Requirements in Pineapple 33 8.3 Application methods 34 8.4 Examples of fertilization application programs for pineapple cropping 36

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Weed Control 38 9.1 Overview 38 9.2 Hand weeding 39 9.3 Mechanical weeding 40 9.4 Mulch covering of bare soil 40 9.5 Application of Chemical Herbicide Sprays 40 Off-season production of pineapple 42 10.1 Overview 42 10.2 Principles of off-season production 42 10.3 Crop Planning for Off-season Production 43 10.4 Flower Initiation or ‘Forcing’ 45 10.5 Preventing Natural Initiation 47 Pest and Disease Control 49 11.1 Pest Control 49 11.2 Disease Control 53 Harvest and Post-Harvest Handling 12.1 Overview 12.2 When to Harvest 12.3 How to Harvest 12.4 Care at Harvesting 12.5 Cartage and Storage of Fruit 12.6 Post-harvest Disorders 12.7 Fruit Grading

57 57 57 59 60 60 61 62

Annexes 63 Annex 1: Pineapple nursery production 63 Annex 2: Practical ways to reduce erosion on the farm 67 Annex 3: Basics of crop nutrition 70 Annex 4: Information on chemical herbicides 78

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Background The government of Vanuatu recognizes that improving the capacity of the agriculture sector to supply the domestic market with locally produced fresh fruit and vegetables is a key strategy to help create new income generating opportunities for rural households and improve food security.

Pineapple has been identified as having unmet market demand from both the fresh and processing sector and is acknowledged as a key fruit crop for Vanuatu farmers to diversify farm income.

Upon request from the Government of the Republic of Vanuatu the Food and Agriculture Organization of the United Nations (FAO) provided technical assistance in the form of a Technical Cooperation Project (TCP) related to ‘building local capacity to produce and process pineapple products’ otherwise known as the ‘Vanuatu Pineapple Project’. For the delivery of the project, Koko Siga Pacific was contracted to provide technical expertise to the Vanuatu Department of Agriculture (DARD) for the execution of this project.

This project aims to build public and private sector capacity to market fresh and processed pineapple products to the Vanuatu domestic market. It takes a whole value chain approach, facilitating interventions in the adoption of improved planting material, improved crop nutrition and off-season production practices; improved harvesting and post-harvest handling practices; and the adoption of improved processing practices in order to provide an important secondary market for locally produced pineapple.

This guide is intended to be used by trainers including DARD, farmer organisations and NGOs. This guide may also be useful for commercial farmers who want a more detailed explanation on agronomics of pineapple production.

This content of this guide was prepared by Aad Van Santen based primarily on the experience of pineapple production on the island of Vanua Levu in Vanuatu. The guide also takes into consideration some of the findings from the limited exposure to pineapple production in Vanuatu.

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Introduction To be successful in pineapple cropping, the farmer has to be serious and fully committed to the crop, since this crop requires a continuous and intensive care over the entire cropping period. This cropping period with pineapple is generally quite longer than Pineapple cropping requires other roots crops or vegetables (a pineapple plant crop can take up to 24 months full commitment from the to come into production while vegetables such as cabbage or tomato take only 1-3 farmer in terms of weed control months).

and plant nutrition, otherwise the farmer will get little to nil production.

Pineapple being a slow developing plant is easily over grown by weeds and can be completely destroyed or, if not too long over grown and cleaned at least loses a number of month’s growth time as well as producing lower yields. Continual weed control in pineapple cropping is an absolute necessity (chemical spray control as well as hand weeding several times per year.) Total crop failure is to be expected if the fields are neglected for a number of months.

Furthermore the farmer is required to have patience, since a pineapple crop takes 1 to 2 years before yielding a marketable harvest.

What to expect from pineapple cropping

From a 1 ha producing area (= 50,000 plants), with 1/3 under Plant Crop (PC), 1/3 under 1st Ratoon crop (1st R), and 1/3 under 2nd Ratoon crop (2nd R), a good farmer can realize the following harvest of marketable fruit;

- for PC between 75-85% of planted crop,

which equals between 12,500 and 14,165 fruits 1/3 ha,

- and for 1st R between 56% to 72% from the planted crop

which equals between 9,400 and 12,000 fruits 1/3 ha,

- and for 2nd R between 43% or 61% from planted crop,

which equals between 7,100 and 10,200 fruits 1/3 ha.

The declining results in harvest allow for a number of plants;

• not growing well, • not fruiting, • malformed fruit, • rat or other rodent damage, • sunburn damage.

The lower results are to be expected for less optimum performance farming, such as a late weeding or reduced fertilizer application, whereas the higher results can be expected from optimum performing farming practices.

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In efficient husbandry practices cropping should not go beyond a 2nd ratoon crop, since after each harvest in general the number of plants is reduced by a range of reasons, resulting in more open spaces. This means more weed growth and less fruits grown, as well as lower quality and reduced size of fruit.

This cropping schedule up to only 2nd ratoon means a total cropping cycle with three harvests takes 3.5 to 4 years.

With a diligent farming approach, the good farmer can spread his harvest practically over the whole year, taking advantage of the higher price per fruit in the off season. The normal season in Vanuatu can be expected to stretch from early November till late January. Pineapple off-season runs from February until October.

Realistic expectations will give a 40-50% of the crop in season or over a 12 week period, and 50-60% of the crop in the off season or over a period of 40 weeks.

Fruit size will not be equal over the entire harvest. Good crop maintenance fruit weight from 0.5-3.5 kg can be expected, with most fruit ranging between 1-2 kg, or an average of 1.5 kg.

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Pineapple Planting Material Pineapples are multiplied and planted by vegetative planting material and not through seed.

This means parts of the old mother plants are used for planting, which gives the same “ genetic “ or “parent like” characteristics as the basic plant the material is picked from.

It is necessary to select the good growing and producing plants to get your planting material from. It is also important that the parts collected from the mother plant are healthy and whole, otherwise a diseased or slow developing plant will be the result.

Different parts of the pineapple plant can be used for direct planting in the field, with each having their different growing characteristics and development stages.

For uniform plant development it is important to plant material with the same development stages and characteristics together in the same units or beds.

Pineapple cropping requires full commitment from the farmer in terms of weed control and plant nutrition, otherwise the farmer will get little to nil production.

The same varieties must also be planted together in the same planting units. If more than one variety is grown, each variety has to be planted separate from others, since these often have different maintenance and care requirements.

3.1 Varieties

It is important to select planting material from varieties that are good producing and well accepted in the market. Smooth Cayenne (“Hawaiian pineapple”) is well accepted on the local Vanuatu market as well as on the export markets. Ripley Queen is well known in the local Vanuatu market, but is rather new in the overseas markets.

Smooth Cayenne Smooth Cayenne (Hawaiian pineapple). Has wide, dark green leaves with no or almost no spines (thorns) on the leaf edges and is easy to work.

It has a large, juicy fruit at optimal maturity. The juice is sweet with a recognizable “pineapple” flavour. The mature fruit is rather soft and more sensitive to transport and handling damage.

Produces few (only one or two) or even no side shoots, often too few to expand

Ripley Queen The Ripley Queen has narrow, long leaves, which are light green, blending to yellow in colour.

The leaves have large spines on each side. Fruits have strong outward protruding eyelets and rind (skin) is light yellow in colour. Fruit flesh has a distinctive spicy flavour. Fruit is rather hard and less sensitive to transport damage.

Fruits tend to be a bit smaller than the Smooth Cayenne fruits. Produces 3-5 new side shoots.

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Some lesser known varieties on the local and overseas markets can be found growing on Efate and Santo including: “Abacaxi” or “Perola” and the “Singapore Spanish”. These varieties have less market importance, but still have demand, especially for the processing industry.

Perola or Abacaxi The Perola or Abacaxi have long erect dark green leaves with fine spines. Mature and ripe fruit is oblong to conical in shape and from 1-1.5 kg in size.

Ripe fruit is still green with center of the eyelets showing some yellow. Fruit flesh is white and juicy, with a unique flavour. Often numerous slips develop just under the fruit base.

The Perola variety is highly tolerant to Phytophtora disease, nematodes and drought.

Singapore Spanish The Singapore Spanish is basically a processing fruit. It has bright green leaves, which can vary from spineless to a few spines on the top of the leaves.

Fruit is cylindrical with red color leaf bracts. Fruit weight is generally small, with rather poor flavour, but good juice quality.

Plant is adapted to high soil pH (soils with high coral sand content). Plant produces many slips and hapas.

3.2 Types of Planting Material

In addition to considering the different varieties, one must also consider the use of different parts of the pineapple plants for planting material. Each of the options described below have their specific advantages and disadvantages, especially as it relates to fruiting behaviour and growth potential.

Consider the following options when deciding on your planting material.

Pineapple top

Pineapple slip

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Pineapple sucker

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Suckers and Hapas Both are the side shoots from the fruit bearing plant and weigh 350g to 1kg.

Smooth Cayenne produces only a few suckers and hapas, while Ripley Queen produces more hapas.

Tops or Crowns The vegetative (leaf rosette) top end of the mature fruit.

Tops are rather equal in size and between 225-275g. Less voluminous than the suckers and hapas.

Slips These are the side-shoots that develop on the fruit stem or just under the fruit. They should weigh between 150-250g.

Nursery Plantlets Small complete plants of 100-200g, developed in a nursery from quartering or stem multiplication methods.

All these different planting material types have slightly different growing characteristics, especially in the initial stages of the crop development; • • • •

Tops will develop slightly slower than suckers, and hapas of the same size and weight.

Slips and nursery plantlets have a slower development pattern than the latter two.

Suckers and hapas produce a less uniform crop, with greater differences in individual plants.

Suckers and hapas are easier to force in flowering than tops or slips.

For more information and advice on pineapple nursery plantlets see Annex 1: Pineapple Nursery Production

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Site Selection 4.1 Land Requirements

A farmer may choose to plant 100 or 10,000 plants based on the availabillly of land, planting material, and the market demands. However, for a consistent supply of year round pineapple it is important to plan out production and land requirements.

To cultivate a pineapple crop with 1 ha under fruit production, assuming 1 plant crop and 2 ratoon crops are planned, an approximate area of 3 ha arable land is needed. This land area is needed for the following reasons; • from land preparation and planting - to first plant crop harvest will take up to two years when tops and slips are used as planting material, • each ratoon crop requires about 1 year development before harvest, • the old crop (third ratoon) is used for planting material provision and occupies land for 1 year, • after 4 years growing pineapple plants on the same area a rotation crop is recommended for at least one year, • finally access roads are needed for the crop maintenance and harvest operations.

The occupied area will thus be divided as follows; - 1/3 ha plant crop (PC)

in production stage

- 1/3 ha 1st ratoon crop (R1)

producing 2nd harvest producing fruit this year

- 1/3 ha 2nd ratoon crop (R2)

producing 3rd harvest producing fruit this year

- 1/3 ha early plant crop

in growing stage

none producing/growing

- 1/3 ha land prep/planting

land prep./planting

none producing/planting

- 1/3 ha sucker production

collect plant mat. only none producing

- 1/3 ha rotational crop

other crop growing

- 2/3 ha for access roads etc.

producing fruit this year

producing alternate crop none producing

Total 3 ha land (1 ha pineapple under fruit production at any given time)

4.2 Selection Criteria

In choosing the location to grow pineapples the following environmental conditions are to be investigated and considered before making the final decision: • climatic conditions such as: temperature, precipitation, irradiation and wind, • field conditions such as; topography, soil type and condition, soil fertility and drainage • logistical conditions such as; accessibility and road condition, distance to market outlet, and availability of transport.

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4.2.1 Temperature

Pineapple is originally a tropical plant. Although it is cultivated over a wide range of climatic conditions, growth below 20o C is reduced, while growth below 10o C will result in no growth or death of the plant. Extended temperatures above 38o C significantly reduce growth or result in death of the plant.

Vanuatu has ideal growing

The optimum temperatures for best vegetative (plant size) growing conditions are conditions for pineapple in terms day temperatures ranging from 28o C to 32o C, and night temperatures ranging of temperature, irradiation and from 18o C to 22o C. The temperature variation in day and night temperature has rainfall. a strong effect on the growth rate. When the day/night temperature range is small, such as 29-32o C, growth rates will be reduced. This factor helps to explain why pineapple close to the coast often perform better due to the fact that sea breezes often reduce the night temperatures appreciably, while moderating day time temperatures.

The above explains why Vanuatu (together with the other South Pacific nations in the tropical latitudes) have such optimum growing conditions for pineapple, particularly those farms near the coast.

4.2.2 Precipitation

The pineapple plant has evolved and adapted to flourish in relatively dry environments.

The pineapple is capable of reducing water loss (trans-evaporation) in hot-dry weather, and even able to collect water in their “funnel� like leaves from morning dew in the absence of rainfall. Again, for this reason lower night temperatures will produce more dew that can be collected in the funnel shape pineapple plants.

Pineapple can grow where other crops die

Although pineapple can endure drought conditions, a minimum of 50 mm water per month (rain or irrigated) is needed for limited growth or to maintain the life of the plant. When higher levels of moisture return, increased growth will take place immediately. This may increase the cropping period, but in most cases the plant will survive low rainfall condtions. Optimum growth is obtained when a good supply of water is available (about 100 to 120 mm/month).

During the cool-dry season in Vanuatu, rainfall can be very limited in certain areas, but pineapple still can collect a reasonable amount of water from dew, produced when the warm moist air heated by the sun, cools after dark, reducing the amount of moisture the air is capable of holding. Under the right conditions, this moisture alone is capable of sustaining an acceptable amount of plant growth in the absence of rainfall.

Funnel shape of pineapple plant collects dew and provides moisture to the plant even in times of drought Pineapple Production in Vanuatu - Trainers Guide

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Drought resistance and dew collection is strongly dependent on plant. Smaller plants have limited funnel shaped leaves to collect the morning dew. Smaller plants results in less soil cover and a higher soil evaporation rate.

Heavy rainfall presents little risk to the pineapple assuming that land has been selected with proper drainage in mind.

4.2.3 Irradiation or sunshine intensity

Quality and sweetness (o brix or quantity of sugar) in pineapple is to a large extent dependent on the quantity of sunshine hours and intensity of sunshine. This also explains why at higher latitudes (farther from the tropics) the planting density is of greater influence on total yield, because at close planting the pineapple plant does not get the optimum radiation or sunshine intensity. However between the tropics (which is where Vanuatu is located for the major part), this problem is not effecting the crop and planting densities up to 55,000 plants/ha will not show lower production because of sunlight (shine) competition nor do lower densities give an increased quantity or quality of fruit per plant.

Important Note: Plantations in a secondary forest clearing or other potentially shaded area should allow for direct sunlight to all plants for most of the day and throughout the entire year as the path of the sun will change significantly throughout the year.

In terms of irradiation, the tropical islands of Vanuatu are ideally situated for pineapple cropping and can produce top quality fruit.

4.2.4 Wind

Most coastal areas have good sea breeze conditions, which favour pineapple growth as earlier mentioned. However these coastal areas are also more prone to heavy wind forces during hurricanes and a lot of taller crops and trees will suffer in those areas considerably more than inland plantations.

But the rather low growing patterns of pineapple makes this crop less susceptible to hurricane damage, especially at high density plantings where plants will support each other. Even the “salty� sea wind, which often effects other crops with its high salt content, has shown little problems with pineapple crops except in cases where sea spray comes into direct contact with plants.

4.2.5 Topography

When selecting a site for pineapple cropping the topography or field lay-out conditions are an extremely critical consideration. The best topographical conditions for especially mono pineapple cropping are flat to light sloping fields in non-flood prone areas. On these fields continuous blocks of uniform quantities can be planted, and mechanized farming practices are easily performed. In the absence of mechanized farming implements, flat fields are still easier to maintain with reduced labour inputs.

Flat to light sloping lands are ideal for pineapple production – both mechanised and non-mechanised.

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Not all farming locations have these optimum topographical conditions and often times sloping land is the only option available.

Steeper sloping fields can be used, but since pineapple is only shallow rooted, these steeper slopes will miss the benefit of erosion protection from the deeper rooted grasses and bush normally growing on these slopes.

Planting pineapple on steep slopes must be accompanied with good erosion prevention practices

Steep slopes should be used with care. Slopes with more than 3% gradient will require well designed surface drainage and an erosion protection plan.

On slopes with a gradient >3%, the field rows should run along the contour (horizontal) not sloping downwards more than + 2 to maximum 3% with fairly short runs to allow surface drainage of excess rainfall water.

To prevent landslides on steep slopes, frequent drains along the contour are required with “down slope� drains, which have to be erosion protected. Also deep ripping on the steep slopes is to be avoided to prevent the partial soaking of the loose top soil in the field, with land sliding as a possible consequence. Do not use deep ripping on a field with slope gradients of more than 5% (this is not more than a drop of 1 meter over 20 meter distance down the slope) to prevent soil erosion and land sliding during heavy rains.

Areas bordering on long and steeper slopes uphill will normally require large enough header drains to collect the uphill water during rainfall and prevent flooding and water erosion in the pineapple fields.

Also avoid fields where rock is surfacing and soil depth is very limited.

4.2.6 Soil type and conditions

Even though pineapple can principally grow on any soil type that allows enough air around the roots, sandy loam soils with an open soil structure and high humus (organic material) content are best suited for commercial pineapple cropping. An open structure soil is required to allow sufficient air to circulate to the high oxygen consuming roots.

Heavy clay soils with a closed and poor structure are not good for pineapple and these should be avoided if possible. If heavy clay soils must be used, deep ripping and extra organic manure before cultivation could improve these heavier soils greatly through enhancement of the draining capacity and aeration. Heavier loamy clay soils also require extra surface drainage canals to allow abundant rainfall to be quickly removed.

High humus content is profitable for pineapple cropping. These conditions are usually found in heavy bush land and cleared secondary forest, but this heavy bush will require extra work and cost for land clearing.

4.2.7 Soil Fertility

Since pineapple is capable of absorbing nutrients through the aerial parts of the plant, there is no immediate dependency on the fertility of the soil. Although it is not ideal, poor fertility soils can be used for pineapple cropping. In the case of poor fertile soils, the farmer must plan to apply fertiliser such as a pre-planting organic manure. Post-planting will require additional concentrated fertilizer for maximum growth and quality of fruit. Even in high fertile soils it should be Pineapple Production in Vanuatu - Trainers Guide

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remembered that the nutrients removed by the crop are to be replaced by fertilization if the fertility level and value of the soil and land is to be maintained.

On poor soils, addition of humus is beneficial for optimum pineapple growth.

During land clearing, avoid the scraping of the top soil in an effort to level the field. This top soil is the highest in nutrient value and humus content.

4.2.8 Soil depth

Rooting depth of pineapple ranges from 15-30 cm for the largest portion of the root mass, but depth of soil should reach at least 500 mm.

4.2.9 Drainage conditions

Pineapple roots require oxygen provided by accessible air. These roots, if deprived of oxygen, will not do well for even a short period of time. Poor drainage and water logged soil prevents air from reaching the roots.

The field should be drained to at least a depth of 1-1.5 m and not subject to flooding during the rainy season. A few hours of water logging can do a significant amount of damage to the roots. Do not plant in places that already act as natural drains.

Even with provision of man-made drains it is very hard to change natural draining courses and flooding is likely to occur in these places during heavy rain.

Fields at the bottom of valleys or flats near creek and river banks are also to be avoided unless proper drainage can be engineered at both low water and high water. Underground water tables may be reaching the plant roots without being visible on the surface.

Low lying areas with potential waterlogging should be avoided for pineapple cropping.

SITE SELECTION SUMMARY

An ideal pineapple site has an abundance of sunshine, sufficient drainage, slight to moderate sloping land, and a soil mixture that contains a sufficient amount of organic matter.

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Land Preparation 5.1 Bush Clearing

Before any final preparation for planting is possible, the land has to be cleared of obstructing trees/shrubs, grasses, and deep rooted weeds that will hamper proper cultivation of pineapple. The shallow rooted pineapple is heavily impacted by competing weeds around the pineapple beds.

When clearing bush however, it is advised, when possible to leave some deep rooting shrubs and trees that are not an immediate obstruction to the pineapple cropping. Some shrubs and trees will help in the prevention of soil erosion. Avoid removal of larger trees by directing the pineapple blocks around or beside the trees.

Shallow rooted trees and shrubs that threaten high competition with pineapple in the higher soil layers, such as “vaivai� tree or guava, should be removed. In case of long grass and small shrubs, these are first cut with cane knife or tractor and slasher on the area that is planned for planting in the coming 3 to 6 months. Obstructing small trees and larger shrubs are cut down with a chain saw and the root stumps pulled out with a tractor or hired bulldozer.

5.2 Pre-planting Weed Control

All large branches are removed from the field and burned in heaps. Remaining grass should be ploughed in for organic material incorporation where possible. Large grass clumps may need to be dug out with a digging fork or spade, making sure all the roots of this grass have been removed. Alternately, the field can be sprayed with a systemic herbicide like Glyphosate to kill the remaining roots, weeds and hard to control grasses. This is especially important for grasses like sedge and nut grass. It should also be realized, that glyphosate herbicide penetrates through the leaves of the weeds and is not taken up through the soil and roots. When Glyphosate comes in contact with soil, it becomes inactive.

When using any kind of chemical, be sure to read and follow all Herbicides can be an effective way to kill unwanted directions carefully. Direct all questions or concerns to your local weeds prior to land preparation. Also follow the dealer where the chemical was purchased. If you choose to use a recommended rates and application methods contact-herbicide such as Gramoxone, you should be aware of the fact that this herbicide only kills the exposed part of the plant and a provided on the chemical labels small amount of root structure near the surface. Gramoxene may not be the best herbicide for deep and thick rooted weeds like sedges and nut grasses.

It is important to kill all hard to fight weeds before planting, since the pineapple plants will remain in the field for at least 3 years, and during that time these hard to remove weeds, which compete for nutrients and light with the crop. This extra work before planting will make a big difference over time.

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The systemic herbicide is allowed to do its work for at least 2 to 3 weeks, without burning or removing the dried up aerial parts of the weeds. Although seemingly dead and dried-out shortly after spraying, the chemical still has to penetrate in live root tips to kill the total plant. If burned or pulled earlier, small portions of the roots remain alive and will produce large and difficult to kill weeds, especially in cases of sedge and nut grass.

Systemic herbicides must be left for 2-3 weeks to properly kill the underground parts of the plant before any burning or ploughing.

For the herbicide Glyphosate (48% concentration),100-150 ml can be mixed in a 15 ltr knapsack to obtain a strong and fast effect on the sprayed plants. However, if the area to be sprayed is near fields or compounds with desirable plants a lower concentration is to be used to avoid damage on wanted plants caused by “drift spray”. If you are unsure about what you are doing, be sure and consult with your local Extension Officer.

5.3 Ploughing and Final Soil Preparation

After the “hard to kill” weeds are killed and removed, the field can be made slightly level with a medium tree trunk behind the tractor or draft animal to fill the uneven spots where shrubs and trees are pulled out leaving holes in the field. If no equipment is available to pull the tree trunk, this levelling of the uneven spots where shrubs are pulled can be done by hand with a spade or fork.

Now the field is ready to be prepared into a fine tilth, which can be done; • by hand with digging fork, spade and hoe; or • with a tractor plough, rake or disc harrow.

Depending on the structure of the soil (heavy loamy clay or light loamy sand), the growing field should completed hand dug or ploughed one to three times in order to prepare a sufficiently deep (150-200 mm) and fine tilth. A final harrowing or ridging/bed preparation is done after final lay-out and planting preparation.

After the large weeds have been removed from the field, the final stages of land preparation can begin.

Good soil tilth can be achieved from ploughing the land by hand or machine.

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5.4 Preparation of planting beds

On level to slightly sloping fields for mono cropping of pineapple, the ideal shape of the cleared field should be such that it fits a multiple of units that can accommodate 1000 plants.

This guide uses as example dimensions of 12 m x 15.5 m per unit of 1000 plants, allowing for 8 double rows of 125 plants at a density of 50,000 plants/ha. (This dimension has been found most practical by the author in crop maintenance, spraying and harvesting, but alternative dimensions of units of 1000 plants can be used.)

Shapes of blocks with multiple units of 1000 plants do not necessarily have to be rectangular, but can be shaped to; • follow contour lines on steeper slopes, or • to avoid mid-field trees and other obstructions, or • if field shape or slope dictates.

In the case of using inter cropping methods with alternative strips of pineapple and other crops, single beds of pineapple can be planted with three lines per bed, again at a spacing of 1.4-1.5 m from center bed to center bed, and bed length of 16.5 m to accommodate 400 plants per bed.

More details on pineapple bed or block lay-out and inter cropping patterns will be discussed in chapter 6.

LAND PREPARATION SUMMARY

Land preparation is very important for pineapple production from initial clearing through to final soil preparation of beds.

Land preparation can be achieved through the use of a tractor or by use of non-mechanized implements.

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Field Cropping Layout Cropping systems in pineapple farming can be divided in three major categories: 1. Sole Cropping: pineapple grown as the single crop in the field.

2. Integrated Vegetable Cropping: pineapple grown with other vegetable crops in between as an intercrop, 3. Perennial Integrated Cropping: pineapple grown as an intercrop in between long term plantings, mostly orchards.

6.1 Sole Cropping

In Sole Cropping entire fields are continuously planted with pineapple, allowing only space for access roads of tractor/ truck and cross escape tracks in continuous blocks for ease of harvest and crop maintenance.

This system should allow for uniform field lay-out and planting, with an ideal shape of the cleared field that fits multiple units that can accommodate 1000 plants. This guide uses example dimensions of 12 m x 15.5 m per unit of 1000 plants, allowing for 8 double rows (beds) of 125 plants/double row. (These dimensions have been found to be most practical by the author in crop maintenance, spraying and harvesting, but alternative dimensions of units of 1000 plants can be used.)

If field space does not allow this size width, partial size of these blocks can be used, like ¼ x, ½ x, etc...

As much as possible harmonization in “unit” size allowing easy division or multiplication in units of 1000 serves for easy adaptation and application of advices on fertilization and other husbandry practices that are based on units of 1000 plants or blocks of 10,000 plants. In any layout, the space between centers of beds should be between 1.4 m and 1.5 m.

Each of the units is started by marking the center of the first bed with the help of simple pegs (sticks) in the middle of the planned double row planted beds. The next parallel beds are marked by measuring with a prepared measure stick of 1.4 to 1.5 mtr from all the previous marking pegs in the first bed at perpendicular angles.

The number of beds per unit depends on the space over the width of the block and could vary from 4 beds for the half size unit to 8 beds in full planted units. Wider than 8 beds is not generally recommended in view of ease of field operations (run in field at harvest, spray applications). On level fields the beds are preferably made flat with the rest of the field, this will make work in the blocks easier and less chance of lodging (falling over of plants) especially in ratoon crops. However on steeper slopes where contours are to be followed, ridges are advised to avoid “sheet erosion”.

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Figure 1: A sample pineapple field layout planting units of 1000 plants and allowing tractor or truck access for spraying and harvesting.

15.5mtr

1 mtr

1 double bed

15.5mtr

st

-1.40mtr

1st double bed

-1.40mtr

1st double bed -1.40mtr

1st double bed -1.40mtr

1st double bed

2 full units of 1000 plants

-1.40mtr

1 double bed st

-1.40mtr

1st double bed

-1.40mtr

1st double bed

-1.40mtr

1st double bed field road of 4mtr.

1st double bed -1.40mtr

1st double bed -1.40mtr

1st double bed

-1.40mtr

1st double bed

-1.40mtr

1st double bed

2 full units of 1000 plants

-1.40mtr

1st double bed -1.40mtr

1st double bed -1.40mtr

1st double bed

15.5mtr

1 mtr

15.5mtr

In cases of flat land with very little slope the possibility of temporary flooding during heavy rain is real. For this reason extra care is given for long beds (200 m or more). In these cases the orientation of beds is to be chosen along the maximum slope direction and additional attention given to preparing raised beds with good drainage, and if necessary deep ripping of the beds.

In larger pineapple farms with wide blocks it is important to leave a space for field roads. For farms using tractor cultivation, the field roads should be between 3 to 4 m broad and at the corners of the blocks a number of plants removed to allow for a turning point.

At the beginning and end of a length of blocks space is to be left for a cross road, to allow tractor and equipment to enter and leave the field roads, without the necessity to cross other planted patches or fences.

If planted on steeper slopes, the contour lines of the slope are to be followed and ridges are to be used instead of planting in the flat on level fields. In principal the same measurements and spacing is used as in level field planting, but the parallel beds are not in straight lines, but follow the marked out contour lines as set-out in the contour survey with an A-frame (see section on erosion control.)

It has to be realized, that especially on steeper slopes the contour lines are not always exact parallel over the entire width of a sloping field. As such beds following the contour lines can be at places shorter and cut off. Steeper slope units might have a different number of beds in the lay-out, because same level (contour) can be less at spaces along the slope width.

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Figure 2: A sample pineapple field layout planting units of 1000 plants on sloping lands with beds following the contour lines.

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6.2 Integrated Vegetable Cropping

There are two basic approaches for intercropping pineapple with vegetables, these include:

1) Mono crop of pineapple with vegetables as a temporary intercrop – In this system pineapple is planted as a

sole crop, but a short term vegetable is used as an intercrop to provide soil cover during the early development period of the pineapple. Since pineapple is a slow developing crop, the first 6 to 9 months provide a space between the planted lines that is bare and exposed to the weather elements.

The intercrop in this system provides a farmer with some income while the slow growing pineapples are being established.

To protect the top soil from erosion effect, as well as to obtain some earlier farm income, a fast growing soil covering crop is selected that does not take more than 6 months to produce a yield and provides fast soil cover and a reasonable returning income.

Figure 3: A sample farm layout that has a slightly wider spacing between pineapple beds to allow for a short term vegetable intercrop 40cm

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This cropping system requires a slightly different planting lay-out, where more space between pineapple beds is required to minimise competition between the two crops. This system also requires an additional supply of nutrients, organic or synthetic, to supply the requirements of the intercrop. This nutrient supply is generally applied to the soil as pre-plant application. It should also be noted, that there is often a slight delay of the pineapple crop in this system, because of the unavoidable competition between the two crops.

The farmer must be careful when using a “creeping” vegetable intercrop in this system to ensure the young pineapple plants are not smothered, the growth of the creeping vegetable must be directed down the center of the row.

Vegetable crops that are hosts to similar pineapple pests and diseases are to be avoided, these include: tomatoes, chili pepper, capsicum and eggplant, which are all hosts and sensitive to the same nematode species as pineapple.

Some vegetable crops that fit well into this system include: sweet potatoes (kumala), long beans, watermelon, peanut, corn, and cucumber. The key to remember is that these crops must be short term and not provide too much shading for the pineapple.

Pineapple can be successful intercropped with many vegetable crops like kumala as seen above. The farmer must be careful that ‘creeping’ vegetable crops do not smother the pineapple.

2) Pineapple cropped in alternate strips with vegetables – In this system pineapple is still the primary crop however there alternate bare strips between the pineapple rows to allow periodical crop rotations with vegetables.

This system uses a number of cultivated strips of similar width, alternatively planted with pineapple and other vegetable crops. The width of the strips can vary according the farmers need, but a general width that can accommodate 3 lines of pineapple is advised.

After a complete pineapple cropping cycle of one plant crop and 2 ratoon crops, a farm can rotate his pineapple to the ‘vegetable strip’ and begin intercropping vegetables on the previous pineapple bed.

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As an example, this system can have three lines of pineapple planted at a spacing between lines of approx. 40 cm and 25 cm spacing in line, with a strip/bed width of 2 mtr to allow for access on both sides. The next strip/bed of 2 mtr wide is now used for planting alternative vegetable crops, in this case not necessarily only creeping crops, but also erect crops such as cassava. As a rotational crop, cassava would also assist to reduce nematode populations.

Figure 4: A sample farm layout that has three rows of pineapple with alternating strips for intercropping vegetables on a rotational basis.

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6.3 Perennial Integrated Cropping

Pineapple can be successfully grown as an intercrop with a range of tree species including citrus, papaya, breadfruit, mango and coffee. In an orchard system, particularly during the establishment phase, pineapple is seen as a highly suitable intercrop that allows the farmer to utilise the wide space between young trees crops.

Experience with inter cropping of pineapple in coconut plantations has been less successful, mainly because the strong tendency of palm trees to develop roots close to the surface soil, which in turn causes heavy competition with the shallow rooted pineapple.

Pineapple intercropped in a breadfruit orchard in Nadi, Vanuatu.

In an orchard system, the space in between the tree lines can be alternatively planted with pineapple, leaving every other space between tree lines open for access to maintain and harvest trees and pineapple. Over the width between the lines of the fruit trees, depending on the spacing of tree lines (often 9 - 12 m), a number of beds with double line pineapple can be planted. Leaving at least 1 mtr from the tree line on both sides of the inter space strip, 7 to 10 mtr is left for pineapple beds.

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Two example lay-outs are presented below: 1) Planting on flat land, where no contour drains are needed, all spacing between trees can be used for pineapple beds, allowing 1 m beside tree lines for the trees. This lay-out allows for 2 strips between trees to be planted with beds of pineapple with a bed spacing of 1.4 m centre to centre, and 1 strip to serve as access road to the pineapple and trees on both side.

Figure 5: A sample farm layout with pineapple intercropped in an orchard on flat land

2) Planting on sloping land with surface drains for erosion control. This lay-out allows for at least 1 m space all around the base of the tree, and then approximately 1 m width for a surface contour drain on the lower side of the slope in between the tree rows, which leaves the rest of the space for pineapple, on the contour lines.

Figure 6: A sample farm layout with pineapple intercropped in an orchard sloping land with erosion on flat land

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6.4 Erosion control on the farm

Soil erosion is a major concern for all farmers working on sloping land and steps need to be taken to address this concern before planting.

Soil loss due to erosion and surface runoff have become severe worldwide problems that all farmers must be aware of.

The problem may become so severe that the land can no longer be cultivated and must be abandoned. Many agricultural civilizations have collapsed due to land and natural resource mismanagement, and the history of such civilizations should be urgent reminders to present farmers to truly protect our natural resources.

Controlling erosion on the farm is not just about protecting your land and environment, erosion actually costs farmers money. Estimates on yield losses indicate that even mild erosion on a field can reduce the yield on that field by 20%.

There are several different types of soil erosion that a farmer should be aware of including: • Wind erosion – This usually occurs on loose (often sandy or light loamy soil) and bare, dry land, when strong and hot, dry winds blow over the area. This is often highly visible as huge dust clouds, well known in desert areas. Although this can be a problem in Vanuatu, water erosion is generally much more significant in our tropical regions.

• Water sheet erosion - This type of erosion is almost invisible, but on uniform, slightly sloping planes of land at each heavy rain a thin layer of the top soil is washed away. This happens on land that is for the most part bare during the rains. Lighter coloured soils are a sign that over time water sheet erosion may have occurred.

• Gully erosion – This type of erosion occurs during periods of heavy rainfall on sloping lands and when the flow of water is not controlled. IN gully erosion, the force of the water over bare soil creates small rivers which carry large volumes of valuable soil away from the farm. This type of erosion is the most common and most destructive that farmers in Vanuatu will experience.

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6.4.1 How does erosion work?

Soil erosion by water occurs when bare soil on sloping lands is exposed to rainfall and the rainfall intensity is heavier than the infiltration rate (this means the water hitting the soil i more than the soil can absorb at one time, leading to soil-surface runoff).

In many natural ecosystems, each raindrop is obstructed by a plant before it hits the ground, where it is then quickly absorbed. In problem areas, where there’s no groundcover, rain drops pound the ground and break up the soil, then wash it away. So soil erosion occurs in two steps, which is loosening of soil particles by raindrop impact/splash, and moving away of detached particles by flowing water.

6.4.2 Different approaches to control erosion

Fortunately there are some proven strategies to reduce erosion, however it’s almost impossible to completely stop erosion – water and wind move soil and that’s all there is to it.

Soil conservation practices that can improve the water infiltration rate of soil, resulting in less surface runoff, can reduce soil erosion. Also making sure that no bare soil is exposed to the environment and rain will improve the protection against erosion. Having the soil covered by plants, crops or mulches is an important step to minimize erosion.

Another strategy to reduce soil erosion is to improve the soil structure/condition, which will improve the rate of infiltration.

The main way to improve soil structure/condition is through incorporation of more organic matter.

Agronomic, cultivation, or structural practices are available for controlling soil erosion.

All these practices are not mutually exclusive. Some situations may require both management and structural changes, in other situations, erosion control can be achieved by implementing a single practice, where the erosion is minimal, such as the establishment of grassed waterways.

Agronomic practises to control erosion include choice of crops and plants to cultivate; deep rooting tree crops will have strong influence on erosion sensitivity, because of the large and deep reaching “network” of the tree roots. This of course is more effective with older trees, and newly planted tree crops themselves will need some erosion control in the first few years.

Another agronomic practise is to leave strips of uncultivated land between cultivated strips of land along sloping areas, assuring that deep rooted bush growth and trees are allowed to grow.

Below are some suggestions for farmers to help minimize the impact of erosion on the farm.

• The most effective way to control erosion is to maintain a permanent surface cover on the soil surface, such as pasture or meadow.

• Choice of crop - shallow rooted crops should be avoided or inter cropped with deep rooting crops.

• Planting along the contour lines of the sloping field, in combination with structural practises of down slope drains with “water force reducing” structures.

• Plant selected trees or shrubs at intervals along the contour between the cropped fields over the entire width of the planted slope.

• Use mulching in between planted lines

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Structural practices involve physical changes in the shape and topography of the land. These include: • Erecting stone walls at intervals along the contour of the slopes. Depending on steepness of the slope these stone walls constructed every 10-20 meters can reduce the force of down slope water significantly.

• Construct terraces on strips along steep slope contours. Care must be taken that terraces are not made too wide, otherwise the upper slope will be depleted of good soil while the terrace is level off.

• Dig header drains above the cultivated field to collect down flowing water from the upper hill areas above the field and prevent additional water flow on the cultivated field.

• Dig down slope drains in a “steps-wise” plan to control the flow of excess water collected in contour drains. These down slope drains should reach to the level of natural water ways.

• Construct “water force” reducing structures in the down slope drains. This will slow the flow of water, reducing the amount soil being carried away.

For more information and advice on reducing soil erosion see Annex 2: Practical Ways to Reduce Soil Erosion on the Farm

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Planting Pineapple 7.1 Collection of Planting Material

The first step in preparing to plant pineapple is to collect your planting material. For more information on pineapple varieties and types of planting material, refer to Chapter 3: Pineapple Planting Material.

Collection of planting material is the first step in preparing to plant pineapple, a farmer should have a good understanding of the variety and type of planting material that is being used

7.1.1 Tops

Pineapple tops are the easiest to collect as they are often removed at the market or on the farm during harvesting. These tops can be stored in heaps on the farm until the time of planting.

7.1.2 Suckers and Hapas

This planting material is picked a few weeks after harvest when the suckers/hapas are of required size. The shoots are carefully pulled from the mother plant, by holding the shoot as low as possibly by its base and twisting the shoot away – downwards from the mother plant.

If another ratoon crop is required, normally at least one shoot is left on the mother plant. The shoot attached lowest on the plant is left for the ratoon crop, while the higher shoots are picked for planting. However if a shoot is much further developed than the rest of the shoots in the field, it is best to remove this shoot also for planting, even if only one is on the plant.

If a restraint in planting material for further expansion is a bottleneck for further development of the plantation, all developing suckers in a harvested field can be collected and used for planting. This will mean however that the farmer must wait for development of new buds /shoots and the next ratoon crop will be delayed for a few months. It will also mean, that the shoots for the next ratoon crop will develop on a higher place of the old mother plant stem, often resulting in increased lodging (falling over of the young plant) when it bears fruits. This risk of lodging can be reduced by picking suckers and hapas as early as possible, which will cause quicker development of the new shoots, and as such development of shoots on a lower place of the mother plant.

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Suckers and hapas bigger than 600 g should be avoided as they plants have often already formed a flower bud on the mother plant or will form a flower bud when suffering some strain after being removed and planted – this is especially the case if collected during the natural initiation or flowering periods (In Vanuatu this is between mid-May and late July). These plants will produce small and unacceptable size fruits.

Smooth Cayenne produces on average not more than 1 or 2 suckers or hapas per plant, or sometimes none at all, and as such is a poor plant material provider. Ripley Queen and Singapore Spanish will produce at least 3 suckers and hapas. The variety known in Vanuatu as ‘Veimama’ produces more suckers and hapas than the Smooth Cayenne, but not as plentiful as the Ripley Queen.

7.1.3 Slips

This planting material can be collected immediately after harvest, since slips will not develop more on the fruit stem after fruit is mature. Only slips developed under the fruit base are used for planting or if only one or two slips have formed at the base of the fruit. If numerous slips are formed on the fruit base this plant, these slips should not be used for planting as they will produce inferior quality fruit (often small in size and deformed).

If many slips have developed on a fruit stem, the slip size will be small. It is best to collect slips that have developed from stems with only 3 to 4 slips / stem which results in more uniform slip size.

7.1.4 Nursery Plantlets

This planting material is collected from the nursery, when a multiplied bed of plantlets has an average size of 150 g per plantlet. All plantlets are uprooted with a garden fork and the roots “washed” loose from each other in water. Plantlets collected from the nursery beds should be covered with wet sackcloth or similar protection against drying out. It is best to collect plantlets in the early morning and for these plants to be planted on the same day. Nursery plantlets should not be stored after uprooting for more than one day. Crop development and fruit characteristics are similar to slips of the same weight range.

For more information and advice on pineapple nursery plantlets see Annex 1: Pineapple Nursery Production 7.2 Storage of planting material

Pineapple tops can be stored for about 3 weeks without a significant impact on quality. However, the longer the storage period, the less uniformity in growth (the individual planted tops will each develop at different rates.)

Suckers and hapas can be stored for several months, depending on size. The heavier the shoot, the longer it can be stored. Again longer storage will impact uniformity of the planted crop.

Nursery plantlets can’t be stored for more than one day after removal from the nursery beds.

Different types of planting material can be stored for different periods of time – pineapple suckers can be stored for several months once harvested while pineapple plantlets must be planted within one day after removal from the nursery bed.

Pineapple Production in Vanuatu - Trainers Guide

After collection of planting material (tops, suckers, hapas and slips) allow them to cure for about one day. This will allow the wound that is formed at the place of separation from the mother plant to dry, reducing infection rates of fungal infections. This is especially true during the rainy season planting.

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Planting material that is stored for longer periods must be sufficiently protected from hot sun and extreme wet conditions.

For storage of planting material, ensure that plants are not stacked higher than ten plants and cover with a shading structure a few centimetres above the top of the pile using sticks and coconut leaves or something similar.

7.3 Grading

Uniformity is the key to commercial pineapple production and therefore it is very important that planting material is graded to achieve uniformity in variety and size prior to planting. As much as possible, each block/row should be planted with the variety and size of plant.

Having different sized planting material in the same bed will result in larger plants preventing the smaller plants from reaching their desired size due to competition for light, nutrient and water. It is preferable to plant smaller sized blocks, than to mix sizes or varieties of plants since this leads to unequal and heterogeneous crop development which is very difficult to manage.

In all cases the planting material used should be more than 150 g in weight and less than 600 g in weight, with the optimum average of 250-500 g of weight.

In selecting planting material from field plants, one has to make sure to collect the material from good producing, healthy plants, that have no abnormalities in fruit development, like multiple tops or abundant development of slips at the fruit base (collar of slips). Grading of planting material should start during the growing cycle with the selection of highly productive plants (positive selection) or removal of unwanted types like multiple crown/collar of slips/very small fruit (negative selection).

When selecting tops, grading for fruit quality is simple because the fruit is easily visible. However for selection of suckers and hapas, plants with inferior fruit should be removed and destroyed or at least marked with paint, when the fruit is harvested from this plant, so that this plant will not be used for planting material collection - this is called rogueing.

Similarly plants with excellent production characteristics can be marked separately with a different colour paint, to mark best sources of planting material collection.

Only slips developed under the fruit base are used for planting or if only one or two slips have formed at the base of the fruit. If numerous slips are formed on the fruit base this plant, these slips should not be used for planting as they will produce inferior quality fruit (often small in size and deformed).

If many slips have developed on a fruit stem, the slip size will be small. It is best to collect slips that have developed from stems with only 3 to 4 slips / stem which results in more uniform slip size. Plants producing fruits with numerous small slips should be removed immediately after harvest or clearly marked so that these plants are not used for planting material selection.

Collected planting material should be graded by: 1. Variety – Smooth Cayenne, Singapore-Spanish, Ripley Queen, Abacaxi, or Veimama 2. Type of plant parts – tops, suckers and hapas, slips or nursery plantlets 3. Size and weight of different planting material - especially for hapas and suckers where this is often great variability To obtain uniform growing units of planted suckers or hapas, this planting material can be graded by average weight groupings of: 250-300 g, 300-350 g, 350-425 g, and 425-500 g.

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An average weight range for slips used for planting is between 150-250 g. They can graded in two groupings: 150-200 g and 200-250 g to obtain uniformity in the field.

7.4 Time of planting

In principle planting can be done, and preferably is done, spread over the whole year. Spreading your planting throughout the year will help enable you to also harvest throughout the year by following the recommended package of practices for off-season production in Chapter 10 of this book.

A year round harvest creates - a more secure market, especially for export, - a more equal spread income over the year and - a spread of work load.

However, not in all cases is planting advised throughout the year, since a certain amount of rain is required to allow the newly planted crop to start growing. A minimum of 50 mm rain or other water supply per month is needed to ensure a good start of newly planted pineapple (this is equivalent to 500,000 litres of water per ha).

For the drier regions in Vanuatu, the months of June, July and August (and in some places even May and September), planting may not be favourable because of very low levels of rainfall.

Establishment of pineapple during dry weather will impact the initial growth of the plants – a minimum of 50 mm rain or other water supply is needed to ensure a good start for newly planted pineapple.

In some cases, a farmer may not have any choice but to plant in the dry season, in this case it is important to understand that without water the newly planted crop will remain dormant until water becomes available. If a newly planted crop is exposed to at least one month without any rain, the plants will eventually dry out and die. Planting of larger planting material, like suckers and hapas, will also offset risk during dry weather as these forms of planting material are more tolerant of resistant to water stress.

Achieving a more even harvest throughout the year can also be done through planting different sizes and types of plants at the same time.

An example of a mixed planting to spread the harvest throughout the year could include: • Tops, small hapas or medium size slips, which take 18 months to develop from planting to harvest under normal growing conditions • Medium and larger suckers which take 15 months to develop from planting to harvest under normal growing conditions, • Small slips and nursery plantlets which take 24 months to develop from planting to harvest under normal growing conditions.

This example is working on a target of 1.5-2 kg / fruit of the smooth cayenne variety.

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7.5 Method of Planting

After the fields and beds have been prepared and planting material has been collected and graded, planting can start.

Graded planting material is transferred into the field and distributed along the beds to be planted. If transferring of planting material into the field with tractor or truck is not possible, then plants can be packed in crates or sacks with a fixed number of plants per crate/bag. Crates or bags will help protect the planting material from drying out during this process.

Graded planting material can be transferred to the field using plastic field crates or sacks in order to protect the plants from drying out.

Using of a nylon planting rope with markers at specified distances can assist a farmer to plant quickly while maintaining the desired spacing.

Each planting bed will have two or three lines, depending on the lay-out and cropping system chosen.

Before actual planting starts, marker pegs can be placed in the center of a bed at the beginning, halfway and at the expected end of the bed, or if the line of the bed is not straight, markers at shorter distances can be placed to enable easy determination of the center of the bed.

A nylon rope of the length of the bed can then be used as planting guide with marker tags at every 100 cm to indicate every 4th planting place and at the start a 1 m space for a crossing path. This planting rope, is placed along the center of the bed using the marker pegs as a guide to determine the places to plant the material with the planting rope in place. Using a system such as this, the material can be planted at the required spacing.

A measuring stick of 1.40 m or 1.50 m length can used to measure the distance from bed center to bed center, if planting is done on flat beds. If ridges are used, the top of the ridges serve as center line for the beds.

First one side of the bed is planted, with one plantlet in line with each marker tag on the planting rope and 10-15 cm from the center of the bed. This 10-15 cm can be measured using the spacing of one spread hand.

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After the first plantlets are planted up to the last marker tag on the planting rope, one more plantlet is planted in between the already planted material in the same line and exactly in the middle between the first planted materials.

Following this practice will result in an “in line spacing” of 25 cm between plants.

After one side of the bed has been planted in this way, than the other side of the bed is also planted.

Here the plantlets are again planted 10-15 cm from the center of the bed or planting rope and at a spacing along the line, such that each plant stands half way in between the space of the plants on the opposite side of the bed. This should then result in an alternate planting pattern, with the plants forming a triangle pattern. In this way optimum use is made of the rooting area for the pineapple plants.

An inline spacing of 25 cm between plants is considered ideal for commercial pineapple production. Using a planting pattern in a double wide row will allow for optimum use of the rooting area for the pineapple plants.

Figure 7: An example of the bed lay-out for a planting density of 50,000 plants/ha.

The numbers 1 = first planted group; numbers 2 = second and third planted groups; numbers 3 = last planted group

It is advisable to allow a 1 m space at the end of the beds to create a ‘crossing’ to facilitate easier harvesting when the time comes.

After this first bed is planted, the subsequent other beds of a block are planted in a same way. When determining the next bed center use a 1.40-1.50 m stick for measurement from bed center to bed center at the marker pegs as used for the first bed.

7.6 Planting depth

Planting material should be planted deep enough to give good anchorage for the plant to minimize the risk of lodging (plants falling over at fruiting stage). Planting material should also be planted deep enough to receive enough soil moisture as the top 3 cm of newly prepared soil is always rather dry, even during rainy seasons.

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However, planting material should also not be planted too deep to prevent soil from falling into the heart of the plant which will delay development and can lead to increased disease pressure.

As a general guide, the following planting depths can be used: • Nursery plantlets of about 150 grams should be planted about 4-5 cm deep, • Slips and tops of about 250 g should be planted to a depth of 6-7cm, and; • larger suckers and hapas of about 450 g should be planted to a depth of 10-15 cm.

For the pineapple plantlets to have optimum starting conditions, the soil around the plantlet has to be in close contact with basal stem and the roots formed in the leaf axils. To achieve this, a fine tilth of soil is required, allowing the fine soil particles to surround the plantlet base closely.

Pineapple plants should be planted deep enough to keep them from falling over but not too deep that soil can enter the ‘heart’. Exact planting depth depends on the size of the planting material and the soil tilth.

This fine tilth also allows an easy and fast method of planting, by “pushing” the plantlet base into the fine tilt soil by hand to the right depth. Coarse soil tilth doesn’t allow close enough contact with the plantlet base, and requires manual digging of planting holes, which consumes much more time as the direct pushing of plantlets into the fine tilth soil.

To ensure better contact of the soil with the plantlet basal roots and stem, the lower leaves can be removed from the planting material, which exposes the basal stem and roots. However this system increases the chance of disease development on the partly damaged plantlet base, as well as being time consuming. If the lower leaves are removed, the plantlets should be given time for the scars (where leaves were removed) to dry up, this will help reduce disease infection. This “curing” also improves the setting of callus and basic root formation on the scars, which gives a better and faster root development in the early stages. If planting is to be done in the dry periods, this method is advisable, since the little available moisture should be made available to the plant as quickly as possible.

7.7 Post Planting Treatment

In cases of high pest or disease pressure in the field, newly planted pineapple blocks may be sprayed with an appropriate insecticide or fungicide immediately after planting. To determine pest or disease pressure and rate of chemical applications, contact your local field officer and/or refer to the Chapter 11 in this guide on pest and disease control.

Immediately after planting is completed preparations should be made for weed control. The objective of early weed control is to prevent the slow growing, young pineapple plants from being overcome by the fast growing weeds.

For early and effective weed control there are basically three methods available depending on availability of materials and conditions on the farm, these methods include: 1. Use of organic mulch material to cover the areas of bare soil between the plants and the beds – this will slow down the development of weeds.

2. Use of plastic or other synthetic mulch to cover the areas of bare soil between the plants. It is the experience of the author that plastic mulch is very problematic for multiple ratoon crops where the plastic because so entangled with the plants that land preparation becomes very difficult. It is also the experience of the author that the common plastic mulch that we have available in the Pacific can cause the top layer of soil to become too hot some days which affects the young roots on this top layer of soil.

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3. Use of chemical herbicides. Chemical herbicides can be very effective in controlling weeds if used appropriately.

Preventative herbicides such as Diuron or Atrazine are the more common herbicides in pineapple as they are not directly harmful to the pineapple.

For more details on weed control see Chapter 9 of this guide.

7.8 Crop Rotation

It is important not to plant pineapple repeatedly on the same block to prevent total depletion of soil nutrients and buildup of certain pests and diseases.

Appropriate crop rotations with pineapple can maintain the fertility of the soil and prevent the build-up on certain pests and diseases (especially nematodes).

For crop rotations with pineapple, it is important to look at crops that will help reduce the population of nematodes.

Some examples include: Tagetus (marigold), castor beans, and cassava. The first two examples do not provide actual farm returns, whereas cassava can provide returns in cash or as food.

It is also important to incorporate some leguminous crops like beans and peanuts into the crop rotation to increase the level of nitrogen in the soil. It is important to remember that even the rotational crops have to supplied with nutrients according to their specific requirements to avoid “emptying� the soil.

Further examples of crop rotations and timings are covered in a series of supporting cropping calendars.

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Crop Nutrition 8.1 Overview

The fertility of the soil or availability of plant nutrients is a major factor determining the yield of all crops. The addition of fertilizers will improve plant growth only if the plant is deficient in the nutrient applied. There may be other growth limiting factors that will not be addressed by fertilizers.

Fertilization will not compensate for poor soil preparation, the lack of water, weed competition and other non-nutrient growth limiting factors!

Managing soil fertility is critical for all farmers regardless of the crop that is being grown. If the soil is not looked after then the farm will not be productive in the long term.

Understanding the specific requirements of a crop in terms of nutrition and the status of your soils are critical elements in effective crop nutrition management. On this basis, it is very difficult to provide hard and fast rules about how much fertiliser should be applied because it depends on various site conditions. As such, fertilization recommendations in this guide should only be regarded as a general guideline with adaptation and adjustments required by the farmer in line with real field conditions. These adaptations and adjustments are mostly done from field observations, analysis of soil samples and analysis of plant material during the period of crop development.

A farmers knowledge of his/her own farm and the basic principles of soil fertility are absolutely essential for success in nutrition management. There is no one size fits all ‘recipe’ when it comes to pineapple nutrition.

This guide provides some basic advice on crop nutrition for pineapple based on a general understanding ofgrowing conditions in Pacific Islands and an assumed zero availability of nutrients in the soil. This advice should be adjusted based on the farmers knowledge of his/her own soil as well as analysis of soil samples and field observations.

Failure to provide the pineapple with the required nutrients (fertilizers) will result in very poor quality and low yielding harvests of small, sour, or tasteless fruits. Trying to save $100 worth of fertilizer can result in a lost income potential of $1000 or more.

Also of great importance is the proper balance of the nutrients available to the plant and in the plant. If all fertilizers are applied to recommendation except for one type, the result will be practically nil and only has an increased yield effect in line with the lowest applied fertilizer. The effect of the applied fertilizers will be nil to very low and the money spent on these fertilizers lost. As such it is understood that besides the amount of fertilizer, also the ratio of these has to be in balance. So if for example, the advice recommends the application of 100 kg urea (N) and 200 kg muriate of potash (KCl), this cannot be replaced by 300 kg urea only or 200 kg urea and 100 kg muriate of potash, since the ratio does additives does not match the needs of the plant.

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8.2 Nutrient Requirements in Pineapple

To determine how much fertiliser to apply, one should know the nutrient requirements of pineapple for optimum growth.

For the Pacific Island context, the author has developed a calculation of the nutrient requirements for pineapple which are based on international research and local experience. The calculation uses the following parameters: 1. No nutrients available in the soil as only P = 10 ppm, Ca < 50 ppm, Mg < 20 ppm 2. Fruit production of 1.5-2 kg 3. Growing climate comparable with Martinique and Hawaii 4. 50,000 plants/ha planted area 5. Planting material size slips or crowns of 250 g 6. Plant crop cycle 17-18 months.

On this basis, the basic requirements for a one hectare of pineapple planted at a density of 50,000 plants are provided below: For plant crop – N = Nitrogen 5 g/plant 50,000 x 5 g = 250 P = Phosphorus if P less than 12 ppm = 25 K = Potassium 1.3 x N or +1.3 x 250 kg = 325 Ca = Calcium if less available than 50 ppm = 50 Mg = Magnesium if less available than 20 ppm = 20 Ca/Mg = 2.5/1 Zn = Zinc if deficiency noted = 1 B = Boron = 1 For the ratoon – N = Nitrogen ± 0.6 of plant crop x 250 kg P = Phosphorus if less available than 5 ppm K = Potassium 1.3 x N or +1.3 x 150 kg Ca = Calcium if less available than 50 ppm Mg = Magnesium if less available than 20 ppm Zn = Zinc if deficiency noted B = Boron

= = = = = = =

150 10 195 25 10 ½ 1

kg N kg P kg K kg Ca kg Mg kg Zn kg B kg N kg P kg K kg Ca kg Mg kg Zn kg B

Note: The above amounts are “pure nutrient” weights and not the amounts of fertilizer to be applied. The amount of the different fertilizers to apply depends on the type of manure or fertilizer used and the estimated percent per volume of each nutrient.

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Each organic or synthetic fertilizer has different amounts of â&#x20AC;&#x153;pure elementâ&#x20AC;? content per kg such as:

Note application: spray= use of spray pump unit or watering can, side dr= side dressing under crop or over recent harvested crop (ratoon start), incorp spread and incorporate into soil before planting.

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8.3 Application methods

The method of fertiliser application also has an impact on the amount of fertiliser required, e.g. if the fertilizer is applied to the soil, an estimated 30-40% of the “pure element nutrient” will be lost by: 1. Leaching (washed away by rain to deeper layers in the soil where roots cannot reach) 2. Fixation of the “pure element nutrient” on the soil particles (like phosphates in the case of most Vanuatu ‘talasiga’ soils, where the high amount of aluminum binds almost all phosphate) 3. Wastage due to the fact that not all soil where the fertilizer is mixed is covered by the roots of the crop If the fertilizer is applied in liquid solution to the plant, a much higher efficiency can be expected. Not all plants will be able to take up all fertilizers through their leaves or stems and efficiency can differ from 70% to 95%.

All nutrients can be taken up through leaves and leaf axils, as long as the fertilizer is dissolvable in water. In the case of pineapple this will give a fertilizer use efficiency of 90% to 95%, assuming the correct fertilizers are used.

With consideration of the above information a basic fertilizer application program can be made, taking into account the following conditions: • small plants will not be able to take up large amounts of fertilizer that is sprayed on the plants • during very dry weather the plant will be less active to absorb the applied fertilizer • the minimum amount of water is given for humid and rainy conditions, has to be increased up to 2x or 2.5x more per same amount of fertilizer to be mixed, if weather is fairly dry and/or windy to avoid burning of the plant by too high concentration of fertilizer (too strong mix). Especially with the spray of Urea care has to be taken, the mixture sitting on the plant should not have more than 3% urea (this is 3kg/100ltr) or more than 10% total mixed fertilizer (10kg/100ltr) • only good dissolvable fertilizer is to be used for spray applications, such as Urea, Muriate of potash, Magnesium sulphate, zinc sulphate, mono- or di- ammonium phosphate, borax and in certain cases potassium sulphate • for spraying fertilizer only high quality fertilizers are to be used in the pineapple cultivation this means urea with low biuret content, potassium sulphate of high purity, muriate of potash (K2O) 60% Solid fertilizer application for the ratoon crops is done by spreading the fertilizer equal along the plant rows in the leaf base of the lower end of the plant. For plant crop the solid fertilizer is applied before disking or ridging, to mix the fertilizer well in the bed during bed preparation. quantities are in + grams, note Organic manures and minerals are preferably spread and incorporated into the soil of “head” meaning container a few months before planting. It is also important to note that organic manures and filled with head full; minerals are generally slow release and some may not even be available to the plant by the end of the 3.5 year growing cycle.

These measurements are approximate figures but serve To assist with simple farm application of fertiliser, the following “average measures as a practical tool for field containers” can be used if no appropriate scale is available: application.

Container type

UREA

M.O.P.

Blend A

Blend C

Large Piala

500

600

580

550

Small piala

200 with head

270

250

250 with head

Small corned beef can

160 with head

250

200

200 with head

Tuna can

150

200

160 with head

150

Large tin fish can

350

480

400

380

Small tin fish can

130

185

160

150

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8.4 Examples of fertilization application programs for pineapple cropping

Based on the above information, the following examples of fertilizer application schedules can be used as guides for individual fertilization schedules, depending on available inputs.

These examples are for units of 1000 plants and applicable to one plant crop and two ratoon crops followed by a rotational crop of cassava.

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These schedules are guide lines and some adaptations are to be made for the different situations and/or availability of specific fertilisers.

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Weed Control 9.1 Overview

Pineapple is a shallow rooted plant which draws its water and nutrients from the top 20 cm of soil. This same soil zone is also where a majority of weed species draw their water and nutrients from which results in significant completion between pineapple plants and weed species.

Additionally, the slow growing nature of the pineapple plant compared with the fast growing nature of most weed species leads to significant competition for water and nutrients. Pineapple plants that suffer significant competition from weeds will not reach their full potential and can even be killed from competition.

Due to the high risk of weeds on pineapple blocks, the farmer must be very pro-active to make sure that weed control is maintained immediately after planting.

Pineapple plants that suffer significant competition from weeds will not reach their full potential and can even be killed from competition.

When the pineapple becomes established the leaves will prevent most new weed growth however in the early stages, the crop is very susceptible to weed competition.

There are different ways to keep the weed growth in pineapple plantations under control, which can be categorized as; • • • •

hand weeding or hand pulling of weeds, mechanical weeding or removing weeds with tools, mulching or covering the soil with organic or artificial material, and, chemical weeding or killing weeds with chemical sprays.

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These weed control methods can be used separately, but in most cases a combination of methods is required to achieve a weed-free pineapple crop. Each of these weed control methods has various considerations for the farmer including: Labour requirements, environmental effects and cost of inputs which are discussed further in this chapter.

A pineapple farm that is free of weeds has the potential to bring good returns for the farmer.

9.2 Hand weeding

Hand weeding is a very effective method of weed control as the plant and its roots are removed from the field. Hand weeding is very effective at the early stages of planting to ensure the crop does suffer much competition. Hand weeding is a very labour intensive method of weed control and also requires the labour to be very attentive so as not to damage the crop. If enough labour is available and affordable than hand weeding is an effective and environmentally friendly method. If pulling of weeds is done by hand, protective cover for hands and arms are required to guard against painful scratching and stinging of the pineapple leaf thorns.

If weeds are properly pulled with roots-and-all re-growth of weed is practically nil. However re-growth of seeds is not prevented, and disturbance of soil, caused by pulling larger roots, encourages seed germination.

Often hand weeding is done in combination with mechanical weeding or in combination with mulch cover or herbicide sprays. For a plant crop (first crop after planting) approximately 3-4 sessions of hand weeding will be needed If enough labour is available and affordable than hand if combined with chemical herbicide sprays. For the one year weeding is an effective and environmentally friendly method. ratoon crops only approximately 2 sessions of hand weeding are needed.

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9.3 Mechanical weeding

Mechanical weeding is generally done using a hand tools such as: digging hoes, hand cultivators, farming knives or the “dutch” pushing” hoe. The aim of mechanical weeding is to cut the weeds at base of the plants using a tool. This method of weeding is labour intensive than hand weeding but has some other disadvantages including: • Mechanical weeding using a digging hoe or hand cultivator creates a risk of digging too deep into the soil and causing damage to the shallow roots of the pineapple. This damage will result in delayed growth and development of the crop and even the possibility of fungus (disease) infection through the damaged roots.

• Similarly, use of a farming knife can result in damage to the pineapple plants or not total removal of the weed roots.

A “dutch hoe” can be a very effective tool for mechanical weeding when applied to small weeds. This piece of equipment is pushed forward to cut weeds just under the soil surface, without damaging pineapple roots by working shallow Mechanical weeding is less labour into the soil. intensive than hand weeding but there is a risk of causing some damage to the From the above it is clear that mechanical weeding can be stressful to the plant roots if the farmer is not careful. pineapple crop. Reducing this stress to pineapple plants is best obtained by early weed activities, which will prevent weeds growing larger than a few cm high or even to prevent any weed growth during early crop growth.

9.4 Mulch covering of bare soil

Covering of bare soil between the planted lines is called mulching. The material used for mulching can be organic materials or synthetic materials.

In general mulching is used: • by larger commercial farms with synthetic materials such as black plastic • by smaller scale farmers using organic materials such as grass cuttings, rice husk and straw, wood chips or saw dust, prunings from special grown trees or shrubs for this purpose, such as Gliricidia, Erytrina, and Calliandra Using organic mulching practices for weed control has an additional advantage of nutrient improvement of the soil.

However, use of organic mulching requires high labour inputs, especially if trees are grown for this purpose, which needs extra work in maintenance and pruning. Organic mulch material also has to be renewed after a number of months in order to remain effective as a weed control method.

9.5 Application of Chemical Herbicide Sprays

Chemical herbicide sprays are another effective method for controlling weeds on the pineapple farm. This type of weed control has the benefits of efficiency and lower labour inputs which is the main reason that larger farms use this method as the main tool in their weed control operations. However, even on large plantations, weed control using chemical herbicide sprays is done in combination with hand or mechanical weeding.

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It is important to note that chemical sprays can negatively impact the environment and even the crop if not applied appropriately. Spray applications and mixture instructions are to be followed exactly and use of chemical sprays should be kept to a minimum essential level.

Chemical sprays should be applied at the early stage of weed growth in order to be most effective, much larger weeds will require stronger sprays which can be harmful to the pineapple plants. In the case where large weeds are present, hand or mechanical weeding can be done in combination with chemical sprays. It is advisable to spray chemical weed control soon after the hand weeding, especially during the wet season to minimize the new weed occurence.

Besides the different application methods of weed control in pineapple, there is also a distinction between weed control systems at different stages of pineapple cropping; which are “pre-planting weed control” and “post-planting weed control” If you choose to use herbicides, do so under the guidance of an Extension Officer and/or a dealer trained in the proper use of herbicides. Always read the directions provided for each product. When used wisely, you can not only save money, but you can also minimize the negative impact on the environment caused by the use of herbicide.

When properly selected and applied, chemical weed control can provide weed free plantations for several months, depending on frequency and heaviness of rainfall after application.

Annex 4 provides more information on chemical weed control including different chemicals that are effective at different stages of plant growth.

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Off-season production of pineapple 10.1 Overview

Under natural conditions pineapple produces fruit for only a limited period of the year called the ‘season’. This seasonal production generally lasts for a period of around ten weeks; November 1 through November 15.. During the pineapple ‘season’, there is a large amount of fruit available in the market and prices are generally low. During the rest of the year, there is very little pineapple available in the market except during a ‘mini season’ which often occurs during June/July.

This guide provides some practical information on technologies to help a farmer to produce pineapple in the ‘off-season’.

By following the system described in this guide it is possible for a farmer to have pineapple available for the market for around 11 months of the year.

The package of practices recommended for off-season pineapple production are as much about preventing flowering during the main season as they are about making the plants flower during the off-season. As such, it is fundamental that the farmer carefully follow all of the recommended steps. This starts with the size of the planting material and the time of planting. Crop planning is essential to successful off-season production.

10.2 Principles of off-season production

The turning of the plant from vegetative growth to generative growth (flower and fruit development) is called flower initiation. In the pineapple plant this naturally happens when the plant experiences longer nights and shorter periods of day light.

In Vanuatu, the difference in day length over the seasons is not too significant and thus it is relatively easy to modify pineapple growth factors to produce fruit during the ‘off-season’.

From flower initiation to harvest takes about 23-25 weeks, during this period the plant experiences a number of changes which the farmer should be able to identify and understand. The first of these changes occur in the first 8-9 weeks and are hardly noticeable. The first noticeable change is the appearance of the “red heart”, appearing around 8 weeks after flower initiation and indicates to the farmer that flower initiation has taken place and that is no longer necessary to treat for forced flowering.

After + 8 weeks the first signs of flower production will be evident by formation of a red flower bud in the heart of the plant ; called red heart

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At about 10 weeks the opening of real first flowers will be noticeable

At 12 to 13 weeks fruit set is apparent.

At 18 to 19 weeks fruit gets mature

At around 24 weeks fruit is full ripe.

10.3 Crop Planning for Off-season Production

In order to produce high quality fruit during the off-season, the farmer must understand a number of important facts about pineapple development and these must be factored into the crop planning. These considerations include: • The size of a pineapple fruit is directly related to the size of the plant – only good sized plants will produce good sized fruit.

• The time from actual flower initiation to harvest is around 23-26 weeks depending on growing conditions during fruit development (if drought conditions are experienced during the fruit development stage than an extra 1-3 weeks are added to the basic 23 weeks).

• Cropping planning and husbandry should ensure 23-26 week growth cycle before planned harvest the plants are large enough to produce a good marketable fruit (to produce a 2 kg fruit, the plants should have a height of 1.4-1.5 m or total plant weight of 4-5 kg at the time of flower initiation).

• To determine whether a plant is ready for flower initiation, it will not be practical to pull plants up and check their weight on a scale, but a simple way to determine readiness is the length measurement of the D-leaf, which is for Smooth Cayenne pineapple normally about 90-100 cm length for a 4-5 kg plant.

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Understanding the D-leaf concept

The “D” leaves are the oldest group of leaves on the plant and are as such the longest leaves on the plant. They are easy to detect by bundling all the leaves together above the plant and choose one of the highest sticking out leaves.

The “D” leaf should be easily removed from the plant with a “left to right” pulling twist.

Leaves with abundant fiber at the base are too old and not a “D” leaf.

Leaves that are narrower at the base than the higher part of the base are too young.

The best way to plan for off-season or year-round pineapple production is to plant a portion of your pineapple plants every month of the year and therefore every month of the year you will have a certain number of plants that are ready for flower initiation.

However, in most cases it is not feasible to plant pineapple every month of the year because of various environmental factors (heavy rain, drought) or even availability of planting material. Still it is advisable for the farmer to plant smaller blocks of pineapple more frequently to facilitate off-season production.

An alternative to planting very frequently is to plant different size planting material at the same time which will also stagger the timing of plants ready for flower initiation and help facilitate offseason production.

A fixed program for this type of operation can’t be given, since conditions and possibilities differ too much from place to place and even from year to year. However it is important to understand the periods of time needed for the different types of planting Measuring the D-leaf is an important tool to determine material in crop planning which are; if the plant is ready for flower induction

Large suckers and hapas need + 6-8 months to reach initiation size and 12 to 13 months for harvest.

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Large tops and medium hapas need + 8-10 months to reach initiation size and 15 months for harvest.

Medium slip and tops need + 12 months to reach initiation size and 18 months for harvest.

Nursery planting material and small slips need + 18 months to reach initiation size and 24 month for harvest.

With this information a planting schedule can be established by the farmer to utilise both time of planting and size of planting material to ensure that plants are ready for flower initiation throughout the year.

For more detailed information on crop planning, refer to Cropping Calendars that describe the time required for different plant types to come into harvest.

10.4 Flower Initiation or â&#x20AC;&#x2DC;Forcingâ&#x20AC;&#x2122;

The sensitivity of the pineapple plant to short-day-length flowering is mainly caused by a chemical gas, called ethylene.

This ethylene is produced inside the plant, and if it accumulates a high enough concentration at the growing tip of the plant it causes the forming of flower buds, which happens during long periods of darkness. This ethylene production in the plant is prevented or reduced by certain pigment bodies in the plant, called phytochromes. These phytochromes are doing their work when they are in an active stage caused by clear sunlight.

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The pineapple plant is highly sensitive to ethylene gas, and also artificial application of this gas results in the plant turning from “vegetative growth” to “generative” growth”.

To produce pineapple fruit before or beyond the natural season there are in principal four possible treatments to achieve this “off-season” production. Three of the methods require chemical applications to the plant, and one method uses manual covering of the plants into darkness.

The most common treatment used around the world involves the use of “chemical flower inductors”, sometimes also misleadingly called hormones. These chemicals are actually not hormones but instead replicate the ethylene gas that is naturally found in the growing tip of the plant.

10.4.1 Chemicals used for ‘forcing’

There are a number of chemicals that are used for ‘forcing’ the plant into flowering. These chemicals all work with varying degrees of effectiveness: The most commonly used chemical is Chloroethylphosphonic acids or ethyphone, available as Ethrel, Ethyphone, or EPGR 10. This chemical is generally used in combination with urea, and in some cases boron fertilizer. The boron compound fertilizer is not really required, but many experts believe it may have a positive effect on the success of flower initiation, especially where a deficiency of this micro nutrient (B) can be expected.

This chemical and the fertilizers are mixed in water and sprayed in the direction of the heart the plants at a rate of approximately 35-50 ml per plant. Spray is preferably done in the afternoon, so the dark evening effect will also benefit the crop. This spray can be done from a large spraying tank on larger farms or with a knapsack sprayer and “high volume” nozzle on smaller farms.

If the urea and ethyphone are mixed in the water the reaction of Ethyphone based products are the most common ethylene production already starts and as such the mixture must be chemicals used worldwide for off-season pineapple production. These products can be applied with used in the next few hours. large boom sprays or simple knapsacks.

Typical mixture formulas are: • For production of fruit close before or after the natural season 100 ltr water, 4kg urea, 70 ml ethyphone, (250 g Borax fert.)

• For production of fruit farther from the natural season 100 ltr water, 4kg urea, 100 ml ethyphone, (250 g Borax fert.)

One spray application is generally sufficient for a 75-80% initiation rate. If a second spray application is given 5-6 days later at the same rate and strength, an initiation rate of 90% up to 100% can be expected, assuming conditions are good and application instructions strictly followed.

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Heavy rainfall immediately after a spray application can wash out the spray mix from the heart of the plant and the leaves.

This will have a negative impact the effectiveness of the application. This ethyphone spray needs at least 3-4 hours to work its into the plant, and the sooner after application a heavy rain is experienced, the lower the effect of the spray will be. If heavy rain occurs soon after application of the spray, another spray the same or next day is advised.

In 8-9 weeks after spray application, effects should be visible in the heart of the plants by the development of “red-heart“, a growth change condition that shows a clear red-flower-bud in the centre of the pineapple plant.

Alpha-Naphtalatic-Acid or A.N.A, is available under the name A.N.A or under a range of trade names recommended as rooting media as well as flowering hormones. This chemical is an auxin and is less effective in flower induction than the above mentioned ethyphone with fruiting rates varying between 30% to 70% effectiveness. This effectiveness rate is considered too low and unreliable for commercial production.

Seasonal day-length differences in Vanuatu are minimal and as such A.N.A can be expected to have a very low and unreliable effect in flower initiation for pineapple. Even though this chemical might be recommended by some people, this author does not recommend the use of this chemical for flower initiation control of pineapple in Vanuatu.

10.4.2 Other techniques for ‘forcing’

An alternative approach to using chemical application for ‘forcing’ is to manually cover plants during the day-time to artificially shorten the day length.

This method uses large black (plastic) sheets that can cover the entire block or bed of pineapple. These sheets are normally placed on frames above the pineapple plants, to prevent damage by the large heavy sheets.

The covering of the plants with the black plastic sheets has to be done at approximately 5:00 pm and removed again the next day at approximately 9:00 am. This procedure is continued for about 7-10 days, depending on the period of the year the system is used. The closer the expected harvest comes to the natural season period, the fewer days of coverage are needed.

This method of artificial flower induction is quite effective, but understandably difficult to apply on a larger scale and thus may only be applicable for small scale production. The method may be an effective option in organic pineapple production where chemical initiation is not acceptable.

10.5 Preventing Natural Initiation

Achieving off-season production can also be achieved by preventing natural flower initiation. Prevention of natural flower initiation is a challenge. Here are two methods that can be used.

1. Encouraging vegetative growth

Encouraging vegetative growth of pineapple plants during natural flower initiation periods is a strategy that can be partially effective. This promotion of vegetative growth during the natural flower initiation periods is about 23 weeks before natural season production of fruit (In Vanuatu this would be end May, June and July).

The vegetative growth conditions are enhanced through additional application of direct acting N-fertilizer (urea) and some K-fertilizer (sulphate of potash ) sprayed on the plants with a liberal amount of water. A spray mix, applied with spray pump unit or watering cans, of 0.5 kg Urea and 0.5 kg sulphate of potash in 80 ltr of water applied about four times on a unit of 1000 plants should be enough.

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This is to be done at about twice a month during the natural flower initiation period, starting in the first half of May. The additional water is important, since the natural flower initiation period in Vanuatu is during the dry season of late May to late July. Make sure these crops are kept stress free from weed competition, because stress to the plant promotes flower initiation.

2. Application of a “light” shock

A light shock of only a couple of seconds in the early evening, a few hours after sunset, is sufficient to give the same effect as a long day for the plant, which promotes activation of the “phytochromes” causing reduced production of ethylene in the plant, and as such reduces strongly the flower initiation effects.

This light shock effect can be done by crossing over the beds of pineapple plants that are to be prevented from flowering with a tube light at normal walking speed. For example an 8 bed pineapple block can be crossed by two men carrying a long stick with three tube holders with lights tied on it, and lighted by a small portable generator.

This light-shock application is to be done above the beds planned for later flower initiation every other day or at least three times a week during the natural flower initiation periods. This method of preventing natural flower initiation is very effective and can prevent flowering in the natural season almost for 95-100%, but it requires some extra investments (small portable generator, TL tube holders and tubes, wire) and additional labour time in the evenings.

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Pest and Disease Control 11.1 Pest Control

Presently there are very few problems with insect pests on pineapple in Vanuatu. The insects that are present rarely have an infestation level that is affecting production.

The two most important and potentially dangerous insect pests for pineapple in Vanuatu are nematodes and symphilids which are both living in the soil and feeding on the pineapple roots.

11.1.1 Nematodes

The most significant economic pest in pineapple which is able to destroy or diminish a crop, are the nematodes. Nematodes are tiny worm-like insects living in the soil in large numbers. The majority of nematode species are not harmful to crops and in some cases they are beneficial to the farmer as they are preying on harmful nematodes and assisting with the break-down of organic matter.

There are some nematode species that can be very harmful to a pineapple, especially if they are present in very large numbers and feeding on the roots of the pineapple plants.

Three major nematode types that are potentially harmful to pineapple are: • the Root Knot Nematode from the “Meloidogyne” family • the Root Lesion Nematode from the “Pratylenchus” family • the more free living nematodes of the “Rotylenchulus” family Nematodes are very small worm-like animals that are hardly visible with the naked eye.

Nematodes feed on roots of the pineapple, killing these through their salivary toxin, The Meloidogne nematode family forms thick knots on the roots, while the lesion nematodes have less distinctive indications of presence.

Nematodes are fairly difficult to kill for the following reasons: • they are quite resistant to normal insecticides, • they are living in the soil where uniform distribution and presence of insecticidal chemicals is much more difficult than above ground • they are quite small and as such less easy to contact with chemicals A distinction can be made among three main systems of nematode control: 1. Bio-ecological control- Relies on soil preparation and rotation of pineapple crops with non-host plant crops.

Here are a few examples of non-host or bad host nematode plant crops are: a. Tagetes (Marigold flower) - this garden plant destroys nematodes to a certain extent with the toxin produced in its root tips Pineapple Production in Vanuatu - Trainers Guide

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b. Cassava – this plant contains arsenic poison in the root skin which kills the nematodes feeding on it, and as such reduces the populations. c. Green panic and sirato grasses - These grasses repel nematodes but are less effective than the Tagetes. A benefit of these grasses is that they provide fodder for cattle.

2. Fumigants – These are general applied to the soil at the final stage of land preparation when very fine soil tilth has been achieved. Nematodes are killed by contact with the chemical vapour of fumigants. The fumigants are injected in the soil at intermediate distances and the liquid than vaporizes and spreads through the entire soil.

The different chemicals normally used as a fumigant for nematodes are: • DD works best at temperatures of 18-20° C • EDB (no longer allowed) works best at temperatures between 20-27° C • DBCP works best at and above temperatures of 25-27° C All three are rather dangerous chemicals, harmful to man and animal if not properly applied. The fumigants kill all living organisms in the soil including profitable and essential microorganisms.

3. Systematic chemicals – Systemics are applied to the soil before planting. The effect is mainly through the poisoning of the nematodes feeding on the roots by the chemicals inside the plant. The chemical is transported to the roots where it kills the nematodes.

These chemicals are mainly taken up by the roots and partly by the leaves and then transported inside the plant to the roots. Some of these chemicals also work partly as contact chemical if applied in the soil.

Systemic chemicals have a longer lasting protecting effect than the fumigants, even protecting the crop later development stages. The systematic chemicals are most active and best applied during favourable times of multiplication of nematodes, which normally is also when the plant is highly active. These chemicals can be applied as granules during land preparation or injected in the soil just after planting when roots are being formed.

The most common chemicals that work as systematic nematodicides are:

The Carbamates Group

Oxamyl- 1-2 months active. Foliar spray every 1-1.5 months at 0.5-1 kg a.i./ha over 3-6 sprays. Plants should not be sprayed 6 weeks before flowering. The carbamates are more and more replaced by the organophosphorus chemicals.

The Organophosphorus Group

Phenamiphos- 3 months active, contact and systemic active apply as granular before planting 10kg a.i./ha or 3 months after planting in several applications 0.075-0.150g a.i. per plant over 3 to 5 applications. Post plant application or as foliar spray or side dress in lower plant parts. This chemical has a negative influence on flowering and should not be applied within 6 weeks before flowering.

Ethoprophos- 3 months active. More contact active and less systemic than phenamiphos. Apply as granular at 10kg a.i./ ha before planting as pre-mix during bed preparation or about 3 weeks after planting as side dress and this side dress repeated every 3 months or when nematodes multiplication periods are good (warm and wet).

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Isazophos- 3 months active mainly active as systemic. Apply before planting as pre mix in soil or about 3 weeks after planting as side dress in the granular form at 9 to 10kg a.i./ha. And repeat after 3 months if nematode conditions are favourable. Isazophos can have negative effects on the vegetative growth at too high concentrations.

A more organic approach to ridding the garden of nematodes is highly recommended. The use of nematodicides should be the last option considered and should be done only under the guidance of an agricultural expert. It is advisable not to over use nemotadicides. Over use of chemicals can disturb the soil flora and fauna and make it “dead” and useless for cropping.

11.1.2 Symphylids

The symphylids are the next most destructive insect pest after nematodes. This insect is a tiny white millipede (Myriapoae) that eat from the root tip. They like to live in loose, light structured soil and is expected to occur less in the heavier clay soils.

Extreme wet conditions or extreme dry conditions reduce pest populations. Under highly favourable conditions (slightly wet/humid soil at 25°-27°C) these insects multiply rapidly and can do considerable damage to the crop.

These insects eat only from the youngest formed root tip (meristem tissue) and cause this growing part to die. The plant reacts by having re-growth of a number of new roots just above the attacked growing point. This results in a “witch broom” effect in the growth appearance and development of the roots if heavily attacked. In the early stages of growth, the plant will suffer from these attacks and prevent rapid root development and subsequent plant development.

Uniform areas can be noted in young plantations with strong reduced growth, far behind the development of the other healthy plants. This is especially clear in the more drought affected areas where root functioning is even more important.

The damage effect is less noticeable in wetter areas, where the roots are faster restored, but only partially. Strong reduction in yields can be expected if these attacks are not stopped immediately.

At present, with the little knowledge of the symphylids biology, only chemical control is proven to be effective. The best results are achieved by the incorporation of the chemicals at planting time which allows a more homogenous control effect in the rooting layer of the soil and prevents attacks during the most sensitive period of development, which is at the early rooting and development stage of the plants.

If chemical control of nematodes is done by pre-planting fumigation or post-planting granular application of “ethoprophos” at the same time sufficient control of symphylids can be assumed.

If no nematode controls done in areas where infestation can be expected, a pre-planting application of Lindane (16%) is advised. Application of 15 L/ha or approx. 35 ml Lindane per 15.5 m pineapple bed of 1.4 m or every 15.5 m bed to drench with 7 watering cans of 10 ltr capacity with each can 5 ml of Lindane (16%). This is to be applied just before ridging up of the beds.

In case of attacks after planting, apply again 35 ml of Lindane per 15.5 m of plant bed, using more water to allow the chemical to penetrate in the rooting area. This means about 10 watering cans with 3.5 ml to drench the chemical into the soil. The amount of water to drench the chemical into the soil depends of course on the moister conditions of the soil and expecting rainfall. The post-planting treatment is not as effective as the pre-planting treatment.

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11.1.3 White grubs or Cane grubs

These insect pests have the potential to cause extensive damage to a pineapple plantation. These grubs are common in soils with plenty of fresh organic material, such as semi-decomposed tree leaves. Attacks are easily noted since these grubs “chop” the roots off and small holes are often seen in the soil near the plant base.

These attacks can be fairly easily controlled with spot application of Lindane at 10 ml Lindane / 15 L watering can for 2.5 m bed. Use these chemicals only if the pests occur or are most likely to occur, since these chemicals also will kill the predators (enemies) of the pests that attack pineapples.

11.1.4 Mealy bug and Pineapple scale

These insect pests attack leaves of pineapple plants. They both normally occur on the underside of the leaves and mostly hidden in the lower parts where shade protects them from direct sunlight. The mealy bug (Homoptera pseudococcines) and the pineapple scales (Diaspis spp.) live from the sap of the leaves but only extreme high infestations will affect the growth and production of plants.

These insect pests mostly occur in higher numbers in the ratoon crops, because they had a chance to develop slowly first in the plant crop and start with fairly high numbers in the ratoon crop. In other pineapple producing countries, these insects (especially mealy bugs) also spread viral diseases that destroy the crop and as such the mealy bug is to be controlled to prevent spread of this “wilt disease” virus. This virus has not been observed in Vanuatu. For this reason, control is not as urgent as overseas, but only when the insects start to infest the fruits, chemical sprays are warranted, since fruits infested with the mealy bug or scales, even if dead, cannot be accepted for the fresh market and surely not for export.

If population of mealy bug and/or scales is becoming too high, a single spray with Diazinon 0.03-0.04% concentration of spray mixture or with Malathion 0.10-0.25% concentration of spray mixture is sufficient until population of the insects return to the original density when last sprayed.

11.1.5 Other pest damages

Sometimes attacks by mynah birds and bats can cause damage to the plants.

The only mitigating measure for these pests is to harvest fruit at full maturity, but before it begins to ripen in the field.

Rats can also be a significant problem on pineapple farms and they often have largest populations in older fields where there are lots of places to hide.

Encouraging mongoose, cat and owl populations around the farm can be an effective way of controlling rat populations. If these strategies don’t work then rat baits can be used, however care must be taken when using these rat baits as they are very dangerous to domestic animals and children.

Wild pigs, goats and cattle can also be pests of pineapple and feed particularly on the ripening fruits. The most effective control for these pests is fencing around the farm.

Rat damage can be a serious problem for pineapple farmers. Encouraging the presence of natural rat enemies such as cats, mongoose or owls is an effective way to reduce rat populations before resorting to rat bait which is potential harmful to domestic animals and children.

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11.2 Disease Control

There are a number of diseases that attack pineapples including fungal pathogens, bacterial pathogens, and one particular virus. Fortunately, Vanuatu only has a few of the major pineapple diseases that are known worldwide. As production increases and intensifies, the presence of disease symptoms may increase.

This guide provides some basic information on some of the major diseases along with various control methods.

11.2.1 Fungal diseases

Phytophthora spp. This fungus is present throughout the world and is well known as a causal agent of “black pod” in cocoa and “brown rot” in citrus. In pineapple, Phytophthora spp. generally causes: • “root rot” attacks the root system resulting in leaves turning from dark green to yellow/pink, the roots of affected plants will either totally deteriorate or turn black with a cavity at the end.

• “heart or top rot” can be identified when the heart of the plant or the centre of the fruit top are attacked with a soft, light brown rotting of the young leaves. Externally the leaves younger than the “D” leaves turn dull yellow to grey while the older leaves appear normal green. The heart leaves are easily pulled out with the base soft brown rotting.

• “green fruit rot” attacks the young unripe fruits with symptoms of grey sections on the fruit with a clear brown edge.

This fungus is spread by water and develops most during the wet season. Most attacks are encountered in cooler periods and on high pH soils.

In major production areas in Hawaii, Philippines, Australia and Malaysia; Phytophthora spp. is a leading production disease capable of destroying an entire plantation.

Despite the widespread presence of Phytophthora in Vanuatu there have been very few reports of serious losses to the farmer as a result of this disease. It is assumed that the strains of pineapples in Vanuatu have developed a fair tolerance or resistance for phytophthora, if well looked after. If plants are heavily damaged (nursery cuttings, fertilizer/chemical burns or other mechanical damage) it should be expected that phytophthora will cause losses.

Preventive control measures for Phytophthora include: • good internal drainage and preventing main drain blockage during heavy rains; • removal and immediate destruction of affected plants and fruits in copper-sulphate solutions or by burning - do not bury or dump infected material up stream near drains or creeks that again pass through the plantations.

If Phytophtora symptoms are observed to be causing losses on the farm, then action should be taken to stop the spread of the disease. The most widely used curative chemical sprays for Phytophtora include: 1. “Metaloxyl” (Rydomyl) @ 0.5-1kg a.i./ha = 7.5kg to 10 kg Ridomyl /ha 2. “Phosetyl-Al” (Alliette 80%) @ 5-6kg a.i./ha = 7.5kg Alliette/ha 3. “Mancozeb” @ 12kg a.i./ha = 15kg Mancozeb /ha 4. “Phosphoric acid” (Agri-fos) 2.5 L a.i. /ha = 6.25 L Agri-fos/ha Phytium spp. This is another fungal disease that affects the roots of pineapple plants and generally occurs in combination with phytophtora spp. The symptoms of Phytium spp. are similar to those of heavy nematode infestation. This disease has not been encountered widely in Vanuatu plantations so far but infection might become much more common as larger Pineapple Production in Vanuatu - Trainers Guide

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plantations are established. It is also possible that pineapple strains in Vanuatu have built up some level of resistance to this disease (as with Phytopthora). If attacks of Phytium spp. are encountered and it is clear it is not due to nematodes, then immediate action should be taken to control the spread of this disease. The same chemical treatments as for phytophtora can be used here: 1. “Metaloxyl” (Rydomyl) @ 0.5-1kg a.i./ha = 7.5kg Ridomyl 10g/ha 2. “Phosetyl-Al” (Alliette 80%) @ 5-6kg a.i./ha = 7.5kg Alliette/ha 3. “Mancozeb” @ 12kg a.i./ha = 15kg Mancozeb / ha 4. “Phosphonic acid” (Agri-fos) 2.5 L a.i. /ha = 6.25 L Agri-fos/ha

Thielaviopsis paradoxa Often misidentified as Ceratocystis paradoxa, it is a common plant fungus in Vanuatu. It affects mostly the aerial parts of the plant although it can attack all parts of the plant. Most infections occur only when the plant is damaged in one way or the other (like cutting for multiplication, fertilizer or other chemical burns or mechanical damage).

The rotting part of the plant, being stem, slip base, fruit or top is black in appearance and has a pungent acid smell. In the stem and leaf material, the vascular tissue (the fibers) is still apparent and gives a black hairy appearance.

If there is no mechanical damage to the plants, the presence of Thielaviopsis paradoxa is not likely to impact production.

In fruits that show cracks between the fruitlets, because of extreme water conditions such as very dry weather followed by heavy rain or vice versa, the disease can easily penetrate the plant and cause damage.

Prevention is done by careful handling of the crop and disinfection of cut planting material with: Benomyl (Benlate) @ 0.15-0.30% in water or;

Triforine (Funginex) @ 0.2-0.3% in water.

Affected parts of the plant by this fungus is easily prevented or cured with the chemicals mentioned above.

11.2.2 Other fungal diseases

Less significant fungal infections in pineapple are Fusarium and Penicilium spp., If present they may cause; fruitlet core rot, black spot, leathery pocket and inter fruitlet corking. Both are considered ‘low risk’ for pineapple producers in Vanuatu.

11.2.3 Bacterial or yeast disease

The most well-known diseases caused by bacteria are: • Pink disease and marbling - The effect of the disease is only significant during processing.

• Fruit collapse and yeasty fermentation, well known in Malaysia and also identified in Vanuatu under favourable conditions, and bacterial fruit “heart rot”.

Pink Disease and Marbling disease

These are two bacterial diseases that show symptoms during fruit processing, especially during heat treatment of slices in the cannery. The disease is as such not yet reported in Vanuatu, but then also canning has been very limited here and if processing of fruit starts the disease can/will probably occur. It is well known in the canning production countries such as Hawaii, Philippines and Australia.

The bacterial disease causes brown colouring of pineapple slices during sterilization. The bacteria causing this disease are thought to enter through the flower during flowering time when sudden changes in weather occur.

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Chemical treatments have had limited success and for the processing industry, the main management approach has been time of planting and plant nutrition. Avoiding flowering during times of heavy rain and addition of extra K fertiliser have been some of the successful strategies to managing this disease.

Fruit Collapse and Yeasty Fermentation

Fruit collapse is caused by the bacteria “Erwinia carotovora” while yeasty fermentationis caused by the yeast “Saccharomyces”.

In both cases the fruit flesh is attacked and rots away and in advanced stages the fruit becomes brown and totally soft and finally collapses with often the skin still intact.

For a yeast attack an alcohol smell can be noticed from the fruit. The microorganism enters through cracks in the fruit between the fruitlets which is mainly caused by sudden changes in climate (dry/wet) with poor plant conditions during advanced development of fruit development and ripening. Also over ripe fruit on the plant is prone to these attacks.

Prevention is possible by cultural practices such watering with spray unit if fruit is ripening during extreme dry weather to prevent the formation of cracks in the fruit. Also K fertilization gives a higher resistance to cracking and prevention of Boron deficiency. (B is applied during hormone sprays)

Bacterial Heart Rot

This disease is very rare and only observed under very specific cropping conditions such as those found on some farms in Malaysia with acid peat soils.

11.2.4 Viral diseases

The two most important viral diseases on pineapple are “wilt disease” and “yellow spot”. Neither of these diseases have been sighted in Vanuatu, however the accidental introduction of these diseases is a very real threat despite good national quarantine systems.

Wilt disease

This virus is of significant economic importance in larger bigger pineapple producing countries with losses of up to 5060% of the crop are experienced. The disease affects the root system in such a way that the whole plant “wilts’ (dries up from lack of water) in the same way as extreme long droughts would do but at a much faster rate. The leaves start to turn bronze to red in colour and dries up very fast. However in Vanuatu, the occurrence of the disease is not yet recorded or noted which could mean the Vanuatu strain of “Smooth Cayenne” pineapple is resistant to the virus or the virus does not yet exist in Vanuatu. Since the virus also develops well in all types of grasses and graminae and is worldwide it is possible that Vanuatu has a resistant strain. As long as this is not yet proven, quarantine rules should prevent importation of any pineapple planting material from countries that have the disease, keeping the country “clean” from this virus as long as possible.

The virus is spread by two types of the mealy bugs (Homoptera pseudoccines). The mealy bugs transmit the “latent” virus by sucking it from an infected plant and injecting it on to a healthy plant when it migrates. Ants act as keepers of these mealy bugs who “milk” these mealy bugs for the honey dew they produce and these ants protect the mealy bugs from predators and spread them to other plants (“pastures”). The species of ants that “breed” the mealy bugs have their nests around the affected plants in a radius of about 7-8 m. The mealy bug itself does little harm to the plant if infection is not too high but if the virus occurs these mealy bugs must be controlled to prevent the spread of the virus. Control of the mealy bug is twofold: • Disinfection of planting material to kill all mealy bugs that might come from the mother plant on the sucker and; • Treatment of mealy bug infected plants during the growth cycle.

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Both can be done using organophosphate insecticides. Spray application must penetrate the shady places of the plant and at the leaf base where the infestation is concentrated. Sprays should be done during the optimum active periods of the mealy bug, this is during humid warm periods.

Chemicals from the organophosphates group that are most commonly used include: a. Parathion @ 0.02-0.03% a.i. in spray at 250-500 L/ha b. Diazinon @ 0.03-0.04% a.i. in spray at 2500-500 L/ha c. Malathion @ 0.10-0.25% a.i. in spray at 2500-500 L/ha

Yellow Spot

This virus is of less importance since it is mainly occurring in the cooler production areas such as the higher elevations of Hawaii, Philippines, Australia, and South Africa. This disease is not likely to affect the cropping here in Vanuatu

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Harvest and Post-Harvest Handling 12.1 Overview

The reward for a farmer’s hard work throughout the growing cycle is the harvest of a crop that will bring income and food.

This final stage of the production cycle is also very important as it determines the quality of produce that will be delivered to the customer/end user.

Here are a couple of important facts related to harvest and post-harvest handling that must be understood.

• The pineapple ‘fruit’ is actually a series of small fruits where each eyelet is an individual fruit. Each of these separate fruits have different development stages, which can be clearly seen during the actual flower development on larger fruits. The bottom flowers open before the top flowers, with a difference of about a week between the very first flowers and the last to develop in large fruits. This difference in development is evident throughout the period of fruit maturity and ripening, and results in the bottom fruit eyelets ripening a number of days earlier than the top fruit eyelets. This is more pronounced in large fruits than in smaller fruits.

• Pineapple is a “non–climacteric” fruit, meaning ripening will not happen properly if the fruit is harvested too early (this is at the still full green maturity stage before the first eyelets start to change colour.) This is in contrast to “climacteric” fruit which will still ripen if removed from the plant at a mature green stage.

These two factors are important to understand when preparing to harvest. Pineapple is a unique fruit. The farmer must understand the ripening characteristics in order to deliver a fruit that will demand top dollar in the markets. The whole fruit must be ready for harvest, before being cut away from the mother plant. Buyers will know how to sample the product and will reject partially ripened fruit.

12.2 When to Harvest.

Do not harvest more than a day before collection or delivery to customer. Determination of ripeness stage is primarily dependant on your ‘market’ or customer preferences.

• for domestic markets close to the farm fruit is normally harvested at ½ -3/4 ripe • for domestic markets that require some transportation linkages (road, boat) it is advisable to harvest at around ¼ ½ ripe • for the fresh fruit export market fruit is generally harvested at the colour break or ¼ ripe stage

Stage of ripeness at time of harvest depends on your market and customer preference. As a general rule, the further the transportation, the earlier the fruit should be harvested.

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12.2.1 Ripeness stages

Presented below are the most commonly recognised stages of ripeness. It is important that the farmer and customer have an agreement on what stage of ripeness they want and what that actually looks like in a practical sense.

Color break

Turning Colour

Quarter Ripe

Half Ripe

Three Quarter Ripe

Full Ripe

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12.3 How to Harvest Below are the two most common methods for harvesting pineapples.

1. Breaking – This method involves holding the fruit by the top and pulling it sideways with one hand, snapping the base stem from the mother plant. The harvester can carry the fruit in one arm and use another hand for breaking new fruit. With this method 5-8 fruits can be picked at one pass. When the harvester’s arms are full, the fruit are brought to the field-road side of the harvested block.

This type of harvest is the fastest method but leaves no “protective” stem at the bottom of the fruit. As such, fruit using this method has a slight shorter “shelf-life” and should be consumed within 4-5 days after harvest. Fruit harvested using this method may also be prone to post-harvest losses due to fungal attacks that enter easily from the bottom of the fruit.

2. Cutting – This method involves using a sharp knife to cut the stem under the fruit base, leaving 2-3 cm of the stem at the base of the fruit. In this way the harvester must use both hands to remove the fruit from the plant; holding in one hand the knife and the other the fruit to be cut.

Pineapple fruit can be harvested by breaking the stem by hand or cutting with a small knife. Both This type of harvest is the slower and more labour intensive, since the methods have advantages and disadvantages. harvester cannot cut and hold the fruit at the same time. Normally the harvester will leave the fruit on the plant to be collected at a later time.

If harvesting with a knife, the stumps should not be longer than 2-3 cm to prevent later damage to other fruit by poking into other fruit’s flesh.

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12.4 Care at Harvesting

Throughout the harvesting stage the farmer should ensure that fruits are handled with care. Fruit must be carefully placed on top of each other when collecting in the arms and placing on the side of the blocks. Fruit is easily bruised. Even if it still feels firm, soft bruise spots will show later in the market and cannot be sold.

Harvesting is preferably done in the early morning to avoid excessive field heat. When harvesting during the heat of the day fruit should not be left in direct sunlight for longer periods. When possible, the fruit should be moved to a shaded area after harvesting.

12.5 Cartage and Storage of Fruit

Collection of fruit from the field after picking should be completed within two hours of picking for maximum freshness and quality. Collecting can be done using a trailer, truck, or wheel barrow.

After fruits are carted from the field, they are carefully off-loaded at the on-farm grading and packing shed. This packing/ grading shed can be an enclosed building or a cleaned area covered with shading such as coconut leaves on erected posts.

This shed should be seen as only a temporary storage area with collection by the buyer to take place the next day.

A farm shed for post-harvest storage and grading should provide protection from: •

• • •

Adverse weather conditions such as hot sun, rain, strong wind, and mechanical damage, such as bruising by rough handling (never throw the fruit around) Excessive weight pressure from stacking (do not pile fruits higher than 3 to 4 fruits) Damage by animals eating from fruit (rats, dogs, horses, pigs, etc.)

As much security from theft as needed

Do not shave the top or crowns from the fruit. This practice has been seen in the Vanuatu markets. It is important to keep the tops and crowns for the following reasons.

• Protection of the fruit during cartage on the farm and cartage to the destination market. By stacking the fruits upside down in transport or storage facility (being van or truck store/packing house or crate) the tops/crowns act as cushioning of fruit and prevent unnecessary bruise damage.

• The green tops still work as natural plant parts producing needed material in the green leaves for the ripening fruit, and as such prolongs storage shelf life as well as helps improved fruit quality esp. in taste

When transporting harvested fruit it is important to place the tops down to provide a cushion for protecting the fruit.

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12.6 Post-harvest Disorders 12.6.1 Internal Browning or Chilling Injury

Preferably fruit should be stored above 100 C to avoid internal Brown Rot or Black Heart. The occurrence of this internal Brown Rot can be expected at temperatures between 9-110 C. This problem, often referred to as “chilling injury”, becomes visible a few days after the fruit is brought out from the cool storage into normal ambient temperatures.

The yellow fruit has a more “dull” appearance and has light brown discoloring turning to black inside the fruit flesh and off-taste of juice.

12.6.2 Fruit Translucency

This is also a physiological disorder of the fruit flesh, giving it a watery appearance. Fruit impacted by this disorder are very sensitive to bruising. Fruit Translucency is most closely linked to poor management practices such as excessive use of urea, and/or insufficient K (MOP). High rainfall periods during the later stages of fruit development may also be a factor.

12.6.3 Sunburn

This disorder is caused by too much direct sunlight on the fruit body during fruit development, especially on hot days >350 C. Sunburn is most common on fruit that have fallen over (lodging) due to excessively large fruit and/or weak stems.

Lodging is also common in ratoon crops where there is a weak base connection of the ratoon plant on the old mother plant.

The higher the number of suckers on the mother plant, the weaker the ratoon base.

Sunburn is the drying out and permanent damage of the fruit skin and the fruit flesh. If only a bit discolouring of the skin occurs this fruit can be still marketed as first grade, but if skin tissue dies and dries out this fruit is generally sold as Grade 2. If too much of the surface is discoloured, the fruit is to be discarded as ‘reject fruit’. A general guideline for sunburn damage grading is: • Fruits with 40% or more of the fruit showing sunburn symptoms are rejected.

• Fruits with 25-40% of the fruit showing sunburn can be still used for juicing, or partially cut-up for piece sales.

• Fruits with 5-25% of the fruit showing sunburn can be marketed as Grade 2 fruit.

Sunburn is a common postharvest disorder that can result in unmarketable fruit.

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12.7 Fruit Grading

In the farm shed fruits should be graded for physical defects, ripeness, and size. Inferior quality fruits should be discarded using the following physical characteristics: • • • •

Poor fruit development & appearance Physical damage caused by rats or other animals Heavy sun-burn damage covering more than 40% of the fruit surface Bruised and soft fruit caused by rough handling during harvest and collection

Good quality fruit – correct stage Poor quality fruit –sunburn and Poor quality fruit – rat damaged of ripeness for good shelf life cracking fruit

Poor quality fruit - multiple Poor quality fruit - heavy Poor quality fruit – over ripe Poor quality fruit – unripe/ crowns collar of slips fruit mature fruit

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Annexes Annex 1: Pineapple nursery production

For pineapple cropping on a commercial scale with a planting density of 50,000 plants per ha, a large amount of planting material is required. For established pineapple farmers it is generally not a problem to obtain the required quantities of planting material from their own plantation, but it is not always easy to obtain the required number of planting material for new farmers.

There are two major reasons for this shortage of pineapple planting material for new farmers are; 1. There is often a shortage of required planting material, since established farmers will need their extra sucker production for their own re-planting programs. This is especially true for the Smooth Cayenne variety, which has a rather poor vegetative reproduction capacity, with often only one or sometimes nil sucker production after harvest, and as such no extra for external supply.

2. The problems that come with the logistics is rather restrictive for new farmers, since the large volume of planting material demands huge transportation inputs.

Just 1000 suckers in the weight range of 350-500 grams fills a 3 ton truck completely to the top, which means planting one ha requires 50 trips with a 3 ton truck to transport enough planting material.

There are two alternative means to obtain large quantities of nursery plantlets, including: 1. Tissue culture of selected pineapple material - this system can provide large volumes of high quality planting material however there must be a laboratory facility in place which is not the case in any of our Pacific Islands.

2. Nursery “rapid multiplication” from sucker and plant stems – this system produces large volumes of planting material with minimal investment and little formal training required.

After a number of years the production of bulk planting material from nurseries will no longer necessary because farmers will soon be able to source new planting material from existing plantations. Farmers will easily be able self sufficient in planting material requirements once they have established a sizeable a farm of atleast 20,000 plants.

Nursery “rapid multiplication” method.

Basic Principals

This “nursery stem-multiplication” system is based on the use of the numerous side buds on the pineapple stem to produce slips that can serve as planting material.

This system works on the principal, that certain chemicals, called hormones, (such as auxins and cytokinins), have a negative or positive influence on the development and growth of new buds in the plant. This negative effect happens with buds on the sides of the plant stems, just below the main growing bud on top of the stem (lateral buds).

With pineapple this is very clear, where initially only one or only a view buds develops into a mature shoot, which form than the producing main stem of the plant. (Especially the Smooth Cayenne has this effect of only letting one or at the most two side buds develop into shoots and major plants, the Ripley Queen has less effect of these hormones and can produce more side shoots on the mother stem.)

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-. Auxins (such as indole-acetic-acid or I.A.A. & alpha-Naphtalatic-acid or A.N.A.) have a negative effect on development of the lower or lateral buds, which than remain dormant or “sleeping”. This hormone is produced in the top growing bud/ shoot and is “pulled” downwards to the lower side or lateral buds.

-. Cytokinins ( such as zeatin and kinetin ) have a positive effect on development of lateral buds, it encourages cell division and growth development inside the lateral buds. Coconut milk (lolo) of young coconuts have shown to contain high concentration levels of these hormones.

The effect of these chemicals at the lateral buds within the plant stems is depending on and influenced by the concentration of the chemical near the buds.

The concentration of the different hormones is determent for the action of this hormone, and as such influences that again controls these concentrations are important in regulating these hormone activities.

For the auxins it is important to promote influences that decrease the concentration of this hormone to lower or stop the negative effect on development of new shoots on the pineapple stem.

These influences on auxins are; - the downward pull of auxins by gravity, away from the sleeping buds on the sides of the stem - inactivation of auxins by light and enzymes in the plant, by exposing the stem surface to light.

- prevent renewed production of auxins in the growing top of a new shoot by timely removal of the shoot.

For the cytokinins it is important to promote influences that increase the concentration of this hormone to promote and/or improve the positive effects on development of new shoots on the pineapple stem.

This can be done through: - increased natural production in the plant through root development - add artificially extra cytokinins to the “sleeping” or dormant buds from natural high concentrated sources

Application of these principals - setting up a pineapple nursery

Below are some steps to construct a simple nursery to produce pineapple nursery plants. This system is a good option for new farmers who don’t have much other planting material.

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Step 1:

Choose a site that is close to the house for easy watering.

Construct a simple bed using waste timber as per the plan below. A bed that is six meters long, 1 meter wide and 20 cm high is a good size.

Step 2:

Fill the nursery bed with a layer of stones or gravel on the bottom (to ensure good drainage) followed by a layer of old saw dust on the top.

Step 3:

Collect pineapple stems from plants that have already fruited, remove all leaves so the stem is â&#x20AC;&#x2DC;nakedâ&#x20AC;&#x2122;.

Step 4:

Using a sharp knife cut the stems in half lengthwise. Stems that are dipped in a fungicide will be better protected from disease.

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Step 5:

Plant the cut stems in the saw dust bed until they are half buried. Ensure that the cut stems are slanting sideways slightly with the top side pointing upward.

Step 6:

Cover the nursery bed with some coconut leaves for shade and ensure that the saw dust is kept moist by watering it daily with a hose or watering can.

Step 7:

Within about 3 months the pineapple stems will sprout several plants. These plants/slips should be carefully removed and placed inside â&#x20AC;&#x2DC;slip bedsâ&#x20AC;&#x2122; once they are around 4-5 cm long.

Plant slips in the slip beds at a spacing of 2-3 cm apart. The slip beds should also be covered with coconut leaves for the first few weeks to provide some shade for the plants.

Slip beds are simple raised planting beds dug in a well-drained soil. A good sized bed is around 1.4 meters wide by 7 meters long. Slip beds also benefit from adding in compost or animal manure.

Step 8:

When the slips are about 20 cm high, after + 3 months, they can be up-rooted and planted in the field as slips. These nursery plantlets will take around 24 months from planting until harvest.

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Annex 2: Practical ways to reduce erosion on the farm

Soil erosion is a major concern for all farmers working on sloping land and steps need to be taken to address this concern before planting. Below are some suggestions for farmers to help minimize the impact of erosion on the farm.

Step 1 - Look for tell-tale signs of erosion

Erosion will look a little different depending on the natural features in your region, but there are a few fairly universal tell-tale signs.

• Check for bald spots. Hillsides and slopes often have places where no trees or plants grow. You might see a build-up of soil below them.

• Look for exposed roots. The soil might be washing or blowing off the top of roots that aren’t normally exposed to the elements.

• Go outside when it’s raining. Look for standing muddy puddles, where the water isn’t absorbed could be a sign of erosion in that area. Watch where the water runs. Watch which direction it seems to be running and where it collects.

Look at the colour of the water in streams.

Step 2 – Identify things you should stop doing.

Here are just a few of the practices which can accelerate erosion: • Planting under extreme dry conditions. The slow growth of young crop means that the top layer of soil is open to the environment.

• Cultivating steep slopes without extra protective action, if possible chose a level area for cultivation.

• Burning stubble and trash after harvest, which removes the protective layer of crop remains.

Step 3 – Take some positive steps to prevent erosion

• Practice minimum tillage. The less you tear up the top layers of soil, the more resistant that soil is to water runoff.

• Stubble mulching. Putting that harvest waste back onto the ground provides an additional layer of insulation against environmental effects.

• Contour cultivation. It’s not suited for all farmland, but it can reduce erosion by 25% to 90%.

• Plant filter strip on runoff areas of your fields.

• Plant grasses and small trees on those steep slopes.

• Use mulching methods between planted lines.

• Consider using a cover crop (especially legumes) during non-cultivation periods.

• Do not pull trees that are not really an obstruction, you can crop around the tree.

By controlling erosion on the farm, you preserve the value of your land and prevent yields from declining.

Contour planting with use of A-frame

Reduce the risk of erosion on sloping fields by planting along the contour lines of the slope. Contour lines are “imaginary” lines running horizontally along the width of the slope, with all points on + the same height or level. By planting along those lines we avoid or reduce the downward flow of water during heavy rain. In such cases the direction of the contour beds are to follow a drop of 1% to maximal 3 % over the length of the.

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These contour lines are set-out along the sloping land with the help of an A-frame, such that all points marked on a contour line are situated on the same level or height. Using these contour lines as guiding lines, the beds or ridges along the slope are marked and prepared. An A-frame is a simple structure consisting of two exact same length legs and a cross bar fixed horizontally on the same height at the two legs. Exactly in the middle of the cross bar is a clear marking, and a string with a weight hanging from the top joint of the two legs.

By placing one leg on a fixed point, the other is moved up or down the slope, until the string with weight is hanging free at the centre mark of the cross bar. Now the second leg is at the same level as the first fixed leg.

Next step is to place the first leg of the A-frame on the newly marked level and in the same way the next level spot is searched/surveyed by checking the moving string on the centre mark of the cross bar. Each surveyed spot is marked with a peg and this is continued until the other side of the sloping field is reached.

Depending on the size of a prepared field, and on steepness of the slope, every 5 to 15 meter down slope one contour line is marked out in this way, and beds or ridges prepared using these contour lines as guiding markers.

The planting should be done on elevated beds or ridges to prevent water running directly down the slope. This water is now gradually flowing to the end of a bed or ridge run, where this water is guided down slope in An A-Frame is a simple tool that a farmer can a controlled way through, step wise constructed down slope drain with use to identify the contour lines prior to planting. drop structures to break the force of the water flow.

Construction of down slope drains

If planting is done along the contour lines of a slope with retaining ridges, rain water over the total length of the ridge/ bed will collect and has to be guided down slope without causing erosion damage. To achieve this we construct a series of down slope drains every 30-50 meters to guide the collected water in a gentle way down the slope.

Total drop 1mtr. over 5mtr.length

Original slope 20% = drop of 4mtr. Over 20mtr. length

Vertical of 95cm (dug in) at drop structure Drop Structures

Bottom of down slope drain at 1% drop = 5cm

The bottom of these must run on a very gentle slope, and we have to dig the top end about one meter down, depending on the soil depth and where hard mother material or rock appears at less depth we stop at that level. Now the drain is further dug down slope with the bottom level at a very slight slope (+ 1%), making use of the A-frame to guide the digging process.

At the point where the natural slope level comes below the surveyed A-frame level, again a new “step” is dug of approx. 1 m deep and again continue digging with a slight slope, till the next “step” level.

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This step wise digging is continued, until the natural down level water ways are reached for natural drainage. These “step wise” down slope drains will need extra protection at the “steps”, where the run-off water will fall down to the next level with quite some force. This protection and depletion of water force is done with “drop structures”, which we will discuss next.

Construction of “drop structures” to break the force of the water

In order to break the force of water in drains several types of structures can be made, ranging from small retaining dams from sticks and twigs to huge concrete stilling basins, with all sort of possibilities in between.

One of the simpler, but still very effective structures is the drop structure made at the “steps” of a down slope drain.

This structure can be made from concrete with all required foundation work etc. which will be a long term or permanent structure, but in smaller scale a similar structure can be made from simple “on farm materials” such as off-cut timber, stones and empty fertilizer or flour bags.

Although these last types of structures are not as long lasting as the concrete one, they should at least serve for an 5 years until some repair overhaul is necessary, whereas the simple structures can be moved without too much problems to another site if need be, which is basically impossible with the concrete structures.

To erect the simple timber structure off-cut timber of approximately 1.25 m is placed and jammed in the ground along the walls of the dug-out step base of the down slope drain. Sides of the step and a few cm width of the rear wall are covered with the off-cut timber, reaching about 25 cm above the base of the top of the step, and jammed into the soil at the lower base of the step. The middle portion of the back wall of the step is also covered with the off-cut timber, but the top end of the timber has to be the same level as the top base of the step drain, in order to allow the collected water to flow down and fall into the bottom of the structure.

The bottom of the structure is dug a few centimetres deeper and filled up with rocks and stones to the level of the bottom step of the drain to break down the force of the falling water. At the bottom outlet of the structure stones are build up slightly to form a “force breaking” wall. The first few meters after the structure the wall of the drain is to be protected with stones dug into the sides.

To prevent the walls of the drop to wash away out of the spaces left between the rough off-cut timber of the structure walls, old / empty fertilizer bags or similar material are spread between mud wall and timber wall of the structure. Over time this soil will settle down well and no further washing away of soil is expected.

Use alley cropping with rows of trees and “filtering” grass

One method to reduce erosion is to plant trees or deep rooted grasses in between rows of pineapple. A range of trees can be used in this form of ‘alley cropping’ including: Erytrina, Gliricidia, Acacia and Calliandra. The trees are frequently pruned to manage the size and the prunings can be used as mulching for the crop.

As an example in pineapple alley cropping along sloping land, three double rows of pineapple are planted along the contour, followed by a single line of gliricidia trees at 1 mtr spacing in line and serato grass planted between the trees.

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Annex 3: Basics of crop nutrition How Fertilizers Work

Plants grow and produce a crop by absorbing nutrients from the soil. Often the nutrients available to the plant are insufficient for crop production, but beside this basic shortage, harvesting also removes nutrients from the soil, and reduces the initial level of available nutrients.

The table below gives an example of how much of the major nutrients (N, P, and K) are removed with harvesting of crops.

Note how high the removal of K = Potash is for almost all crops, a nutrient generally already low in most tropical soils, and particularly in Vanuatu.

Table 10: Nutrients that different crops remove at harvest from the soil.

Crop

Yield (Ton/ha)

Nitrogen Kg/ha N

Phosphorus Kg/ha P

Potassium Kg/ha K

Banana

Fruit

30

60

7

164

Citrus

Fruit

15

100

11

180

Cassava Cocoa

Tomato

Pineapple

Pineapple

Roots Beans Fruit

Fruit

Sucker

20 1

75

55

55

125 20

112 43 25

13 5

11 7

3

125 12

202 110 43

These removed nutrients have to be replaced, if farming is to be sustainably continued. Fertilization/nutrition of soil is a continued cycle of adding nutrients (animal manure, compost, mulching, crop residues, and synthetic fertilizer) and removing them through harvesting crops and weed growth. The next picture gives an idea of this nutrient cycle on a farm.

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So these removed nutrients are to be replaced if we want to apply sustainable farming while obtaining a continued good yielding crop from those fields.

Now it has to be understood, that organic manures, composts, mulches or synthetic fertilizer are not magic substances, but simply combinations of minerals that are used by plants to grow and produce.

These minerals each have a certain function in the growing, development and production process in the plant. A proper balance in fertilizing nutrition is needed to get optimum growth and production effect, or in other words the right proportions of the different animal manures, composts, mulching, mineral or synthetic (straight or compound) fertilizer are to be used if we want to get the required high yield results.

To be able to use the right fertilization program and application in his/her crop the farmer has to have a basic knowledge of how these fertilizers are taken up by the plant and what these fertilizers do in the development of the plants and the total crop.

We first will look at what nutrients or minerals the plants use and which ones are required in the largest quantities.

Plant Nutrients

According to the quantities used by the plant, nutrients are divided into; major or primary nutrients, minor or secondary nutrients, and micro nutrients.

The following categorization can be made based on quantities used by the plants: Hydrogen or H - These are used in highest quantities, but generally available in large volumes Oxygen or O - Supplied by water in the soil and from the rain (or irrigation) Carbon or C - CO2 and oxygen or O2 from the air Those 3 nutrients are most needed by the plant and used to produce plant building material and energy storage material such as starch (cassava, dalo, potatoes, breadfruit), sugars (sugarcane, pineapple, mango, citrus), proteins (soya bean, split pea, long beans, green peas), etc. These nutrients are normally sufficient and do not need to be supplemented with extra fertilizer, except perhaps as water in irrigated crops, but this is outside the scope of this presentation.

Nitrogen or N - supplied by decomposed material (humus) and as a synthetic fertilizer Phosphorus or P - supplied by minerals on soil particles or as synthetic fertilizer or organic manure Potash or K - supplied as minerals on soil particles or as synthetic fertilizer or organic manure Pineapple Production in Vanuatu - Trainers Guide

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These are used in large quantities by the plant and called Primary or Major Nutrients. These are used by the plant for different functions and production of important plant organs and growth factors, which we will look a bit closer at next.

Calcium or Ca - often in large quantities in the soil, or supplied as mineral or synthetic fertilizer Magnesium Mg - supplied by minerals on soil particles or as synthetic fertilizer or organic manure Sulpher S - less needed and mostly available as by-product in synthetic fertilizers.

These are used in lesser but still fairly high quantities and called Secondary or Minor Elements. Again these are used by the plant for different functions as well as for soil condition improvements, which we will look a bit closer at next.

Iron or Fe - These are supplied as minerals on soil particles and in different organic manures or to lesser extent as synthetic fertilizer Manganese or Mn Boron or B Zinc or Zn Copper or Cu This group is used by the plants only in very small quantities, and called Micro Elements.

These nutrients are available in the soil in different quantities and/or added to the soil through; - plant residues from harvested crops or from weed control operations - addition of organic manures as animal manures, bone and blood meal from abattoirs, etc.

- composts (from garden or household waste) - organic mulching material (grass cuttings, rice husk, bagasse of sugar mill, Gliricidia cuttings etc.

- natural minerals, as coral sand, rock phosphate, mineral potassium salts, etc - synthetic fertilizers, as straight fertilizers or compound fertilizers.

However these different “nutrient enriching” additions contain different quantities of the mentioned nutrients, and to obtain the right balanced nutrient condition for the plant, the right combinations of manures, compost, mulching, and fertilizer has to be chosen.

It is also to be realized, that different crops require different total quantities of each of the mentioned nutrients, such as differing quantities of major, minor and micro elements. These basic facts mean, that increase of nutrients will have to be balanced if the expected effects of crop yield increases are to be obtained. A high amount of a certain nutrient element or straight fertilizer will not have the expected and required effect if another element is still lacking or low in availability to the plant.

The Law of Minimum

Here the rule of the lowest available nutrient is applicable, which means that the plants will only grow and produce according to the lowest available nutritional element available. This is called “the law of minimum” and is best demonstrated with the “water barrel level” explanation as shown below.

The law of minimum is often illustrated with a barrel of water with different side-stave lengths. The barrel’s capacity to hold water is determined by the shortest stave. Here it shows that the barrel cannot hold more water (crop yield level) than the lowest of its side stave of N or Nitrogen (lowest nutrient level optimum). It has to be realized that the lowest optimum nutrient level does not necessarily mean lowest quantity of all the nutrients, but this means that for instance if N (Nitrogen) is at the lowest optimum level of all the nutrients, the total N can be still 2 to 3 times more in quantity than P (phosphorus), but the plant requires much more N for growth than P. Pineapple Production in Vanuatu - Trainers Guide

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Sampling

The following procedures are to be followed if the farmer does not trust his own judgment on visual fertility observations, and wants assistance of additional analysis results.

Soil samples are taken from about 10 to 15 places in the field over an area of 1 ha.

The sites where the samples are taken should be representative for that field to give a good idea of the total field condition of the soil. This means not to take samples from sites that are strongly different from the rest of the field, but take samples from sites that are similar to the rest of the field A good farmer is expected to know his poor and good spots, especially if the field has been cropped before.

To collect the soil samples, first scrape the first 1 to 1.5 cm of top soil away, and then dig about 10 cm wide and 20 cm deep at each of the sampling sites. Mix the dug up soil well and take + 2 hands of this in a big plastic bag. Repeat this for each of the sampling sites, putting all the soil in the same plastic bag from a uniform field. Each of the bags is now thoroughly mixed and lumps of soil made fine and the whole sieved.

From this mixture, about ž kg is taken and put in a smaller plastic bag. Two labels are used with information of; - the site of the field/farm where the sample is taken, - the date the sample is taken, - the name of the farmer and address and, - the crops previously grown on the field.

If the field in question has different fertility areas, mark the different sample bags with separate indications like a, b and c. Place one of the papers with the information of the field and samples in the bag, close the bag firmly with a twine or a knot in the bag top and tie the other piece of paper with a twine on the top of the bag. Make a rough field sketch and mark where the different fertility area as a, b and c are located and keep this sketch for later reference, when the analysis results are available, so it is easy to remember to which areas the results refer. All sample bags are now placed together and send to the laboratory through your agricultural officer for analysis.

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Leaf sample - To have an optimum monitoring of pineapple cropping, it is advisable to obtain leaf samples at two or three development stages of the crop. One sampling can be done ± 4.5 months before flower initiation and before the next fertilizer application.

A second sample might be required if crop performs low, but is not always needed. This will be approximately ± 2 months before flower initiation and before the next fertilizer application. A final leaf sampling can be done to ensure an optimum fertilization just before the important flower initiation and at approximately ± ¾ months before flower initiation and before the fertilizer application.

For new and just starting pineapple farmers, at least one leaf sample is advisable to obtain nutritional status information just before the last fertilizer application and subsequent flower initiation. More experienced farmers might judge nutrient status and needs from the appearance of the crop.

Fertilizer after flower initiation (hormone spray or natural flowering) has little or no effect on the crop to be expected for this season, but only benefits the next crop. This accounts especially for N. Rectification of fertilizer application is to be done as immediately after the results from the analysis are known.

For leaf analysis it is important to determine potassium (K), calcium (Ca), and magnesium (Mg) levels in the leaves and if deficiency is suspected also for phosphorus (P) and nitrogen (N) levels. Although the last element level (N or nitrogen) can normally be easily determined from field observations on color and shape of leaves. Light green narrow leaves indicate a shortage, yellow leaves means great shortage of N, while deep dark green and wide soft leaves indicates a too high level of N. Good appearance is a deep green, equal color with turgid leaves standing well erected.

Leaf samples in the field are taken from the ready blocks and kept as a separate sample unit. From each block of 10,000 plants, 5 to 8 plants are sampled, with removal of one “D” leaf per plant. The sampled plants should be approximately the same size as the total average of the plants in the block, and do not take samples from plants that are much bigger or smaller or show different appearance than the most of the other plants in the block.

The “D” leaves are the oldest, still growing group of leaves on the plant and are as such the longest leaves on the plant.

They are easiest detected by bundling all the leaves together above the plant and choose one of the highest sticking out leaves. The “D” leaf should be easily removed from the plant with a “left to right” pulling twist.

- Leaves with abundant fiber at the base are too old and not a “D” leaf.

- Leaves that are narrower at the base than the higher part of the base are too young.

The entire leaves are now bundled together and put in a plastic bag. One piece of paper is put in the bag with the leaves and one piece of paper is tied with a string to close the bag. Both pieces of paper mention the date of sampling, farmer name, farm location, block number and stage of growth of the plants.

The samples are sent to the laboratory for rapid analysis so that in a few days the results of the analysis can be Pineapple Production in Vanuatu - Trainers Guide

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given and with advice of your field officer an adjusted fertilizer application can be made. This is especially important for the last fertilizer application before flower induction is done.

Nutrient sources

Nutrient content of some of the most common manures, compost, mulching, minerals and synthetic fertilizer is given in the next tables for reference and assistance in nutrition management. However it has to be realized, that for most organic manures and composts average content can differ considerably, due to different feeding conditions of animals (animals canâ&#x20AC;&#x2122;t excrete more than what they eat).

For mineral material such as wood ash, coral sand etc. the content is more stable but again can still fluctuate depending on basic material used or place collected (type of wood, coconut husk, and location of mines).

Despite these variations in especially organic fertilization material, it is still necessary to consider the expected nutrient values to come to a balanced nutrition for the crops.

Average nutrient composition of fresh animal manures (percent of fresh weight) Source Water content % N P2O5 K2O Beef cattle 80 0.70 0.45 0.55 Dairy cattle 84 0.60 0.25 0.60 Pigs 75 0.50 0.35 0.65 Sheep 65 1.05 0.35 0.95 Poultry 75 1.00 1.25 0.50 Average nutrient composition of dried manures (percent dry weight) Source N P2O5 K2O Dairy cattle 1.3 0.9 3.0 Pigs 3.5 0.5 0.7 Sheep 3.5 1.4 3.5 Poultry 3.2 5.2 1.8 Blood meal 13.0-14.0 2.0 1.0 Bone meal, raw 3.0 20-30 -Fish emulsion 5.0 2.0 2.0 Sewage sludge* 1.0-5.0 1.3 0.4 Green manure 1.5 â&#x20AC;&#x201C; 5.0 0.2-0.5 Compost 0.5 â&#x20AC;&#x201C; 2.0 0.2-0.5 Seaweed 2.0-3.0 12.0 Average nutrient composition of natural minerals (percent dry weight) Source N P2O5 K2O CaCO3 Rock phosphate 0 17-26 0 0 Egg shell 1 0.5 0 93 Wood ash 0 0 5-10 0 Coral sand 0 0 0 93

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Before focusing on synthetic fertilizer contents, first a few remarks on organic based materials: - Animal manures contribute more to the soil than just nitrogen, phosphorus, and potassium. Continued use of manures builds organic matter in soils and improves soil structure. This modification of soil structure helps improve water holding capacity, aeration, friability, and drainage. In addition, many trace nutrients needed for optimum plant growth are available from manures.

- plant nutrients are released more slowly and over a longer period of time than from most commercial fertilizers.

- Disadvantages of using manures are the handling and transportation problems associated with large amounts of manure required to obtain sufficient quantities of nutrients for crops.

- The use of fresh manure may also introduce new weeds into fields since certain weed seeds remain alive even after passage through animals.

- If fresh manure is used on soil, it should be worked in as soon as possible or covered with other organic materials such as straw, hay, or grass clippings to prevent the loss of nitrogen through leaching and evaporation.

- Allow at least one or two months to pass before planting after fresh manure applications. This allows soil microbes to start the decomposition process that regulates nutrient availability and prevents burning of young plant roots. No fresh manure may be used during the year of harvest for certified organic production.

- It is important to remember that nutrient contents in manures vary widely according to age of the animals, feed used, moisture content, degree of decomposition, and the amount of litter mixed in with the manure.

- Manure applications should never exceed the total nitrogen requirements of a crop in an attempt to satisfy phosphorus and potassium requirements--burning of the roots and leaves could occur.

- Seaweed is a rich source of potassium, up to 12%. Though seaweed contains many trace elements, it is poor in nitrogen and phosphate. Large volumes of fresh sea weed are needed to obtain the dry weight volume.

- Eggshells are 93% calcium carbonate In addition to the calcium, the eggshells contain about 1% nitrogen, about a half-percent phosphoric acid, and other trace elements that make them a practical fertilizer

Average nutrient composition of synthetic fertilizers (percent dry weight)

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Major Nutrient activities in the plant/crop.

To get an idea of which type and combination of fertilization applications are needed for a certain type of crop to produce the required quantity and quality of produce yield, an indication of the reaction and result in the plant of some of the nutrients is given below.

It is to be understood that in the scope of this presentation, that no deep scientific explanation or discourse is given, but only general “rule of thumb” indications of the most important effects of the major nutrients. This is for farmers in the field to understand in great lines how to improve their crop with a balanced fertilization practice.

Nitrogen or N

All living organs are built-up from a large amount from proteins, including plants. One of the “building blocks” for these proteins is nitrogen or N and to enable good growth, sufficient N is needed. Also the green parts of plants, called chlorophyll, which is responsible for making sugars in the plant, has nitrogen.

From this we understand now that providing more nitrogen or N to the crop; - the plants grow bigger with more bio-mass or total plant volume.

- the plants produces greener leaves.

- the plants produce more sugar, starch or other food materials like proteins, oils, vitamins etc.

Phosphorus or P

For the transfer of energy to places where it is mostly needed phosphorus is a major element to make this possible. A lot of energy is used at the growing tops of the plant and phosphorus-deficient plants, therefore, are stunted with a limited root system and thin stems.

In most plants P is needed to improve and allow; - root (tip) development and growth, especially in the early stage.

- young growing tip or bud development - better development and health of flowers and fruit set (less flower drop and more fruit set) Fruit trees deficient in P have few and short new shoots and malformed fruits and seeds. Thus not only low yields but also poor quality are the results of P deficiency.

Potassium or K

Potassium is involved in; - water uptake from the soil and long distance transport of water in the whole plant, where water supply to all the plant organs and tissue is crucial, and as such is important for optimum plant growth and production.

- water retention in the plant tissue, potassium is required for maintaining osmotic pressure of cell, that is, K makes plants look turgid. Since K regulates the cell turgidity, and the close or open conditions of stomata (breathing organs), it plays an important role in water regulations in the plant and drought resistance.

- transport of sugars and other photosynthesis products from the leafs to the storage organs, in connection with this fact the provision of sufficient K improves size and quality of storage parts of the plant such as; root tuber (larger cassava roots with more starch (food) and less fiber (soft cooking) fruit size and quality (sweetness or brix, brix/acid ratio, flavor) sugar content in stem (cane) grain size (rice, wheat, beans etc.)

- with adequate K, cell walls are thicker and cell more turgid, thereby producing stronger plant stems and improving plant resistance to lodging (less lodging in cane , pineapple, rice etc.).

- K produces also more elasticity in the cell wall, especially in the epidermis (plant skin), which results in less cracking Pineapple Production in Vanuatu - Trainers Guide

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of the rind (skin), thus providing better protection and resistance to attacking diseases. (like the strong growth of large watermelon, where often the skin at the end where the flower sits, starts cracking and allows sickness as fungi to enter (blossom end rot)).

- fruits and vegetables grown with adequate K have a longer shelf life in the storage.

Consequently, K-deficient plants show low resistance to disease, their seeds and fruits are small and shrivelled. In tomato, K deficiency results in smaller fruits whose flesh development is incomplete. The stalks are weak and lodging is common.

The most visual K deficiency symptom is the scorching or firing along leaf tips and Unlike N and P nutrients, which both form part of the actual plant organs, Potassium or K are moving as free nutrients in the plant, mostly in the sugar transport organs (phloem).

Calcium or Ca

Calcium is mostly responsible for a stronger skin and body flesh of root tubers and fruits, which gives better resistance to damage during cultivation, harvest and packaging/ transport. Fruit and vegetables containing higher levels of calcium also have a higher nutritional value â&#x20AC;&#x201C; for example, vitamin C and antioxidants in tomatoes Furthermore Ca is important for soil structure improvement, which again allows roots better growth and nutrients better released to the plant.

Magnesium or Mg

Magnesium is an integral part of the chlorophyll in the plant, which is the part that produces the sugar and food from sunlight. As such Mg improves again the sugar and stage or other food production in the plant, increasing yield. Grain fill in rice and dry matter content of potatoes can be significantly reduced if magnesium is undersupplied.

Annex 4: Information on chemical herbicides

The range of herbicidal chemicals is large, and not all herbicides can be used for the same purposes or applied in the same way. Each has its own specific characteristics, field of use and way of application. Below is a short description of the most common herbicides used in pineapple and is given as general guideline.

First a farmer must understand the different classifications given to these herbicides, which describes their range and way of action on weeds and plants in general. (Because what is a weed - a cassava plant in the middle of a mono cropped pineapple field is regarded as a weed.).

The first major division in herbicides is; Non-selective weed killers - these herbicides effect and kill a very wide range of plants, including the crops planted.

Selective weed killers - these herbicides effect only certain groups of weeds, and has little to no effect on others plants, such as our crops.

The second major division in herbicides is; Systemic weed killers - the way of action of these herbicides is through-out the entire plant, being taken-up by the plant through roots or leafs and transported to other parts of the plant. As such if even only one portion is in contact with the herbicide, the chemical is spread from there through the entire plants and effects the complete plant.

Contact or non-systemic weed killers - this herbicide is not taken up by the plant in its system, but only effects the portion that is in contact with the chemical. As such, parts that are not touched by the herbicide are not affected. This type of herbicide is also not taken up through the roots, but only works on the upper parts of the plant (above soil level).

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With this in mind we can identify and select the right herbicide from the following common pineapple herbicides.

Non selective weed killers Paraquat - this weed killer is a non-selective, contact herbicide. Because it is a non-systemic or contact chemical, paraquat only effects the parts above the soil that are sprayed while the roots are not or only very little effected. In cases of deep and thick rooted weeds like sedges and nut grasses, these chemicals do not provide sufficient activity to kill the deeper roots. These weeds can develop again, this is especially true for grasses like sedge and nut grass. If an area is well known for re-growth after clearing and cleaning by certain seed born weeds in the soil (like kaumoce, chakorda) a paraquat spray works well to eliminate these weeds. Best is to allow this seed born weeds to develop into a young stage, after which a paraquat spray will kill those weeds.

This chemical is neutralized if it comes in contact with soil and is not adsorb by the roots and has no residual effect in the soil or ground water.

Glyphosate

Glyphosate

Glyphosate, this weed killer is a strong non selective herbicide, and fully systemic in activity.

Glyphosate has a deep systemic action, in such a way that it penetrates throughout the plant up to the growing tips as well as deep to the far end root tips, if enough time is given to penetrate.

The systemic action of this chemical works throughout the entire plant killing all parts. However the movement inside the plant is rather slow and the chemical needs time to reach all parts.

(Up to 2 to 3 weeks for larger weeds). When using glyphosate for total weed control, it has to be realized, that glyphosate herbicide penetrates through the leaves of the weeds. As soon as glyphosate is in contact with soil or dirt it will not do its work anymore. Most effect is obtained when weeds are about 15 to 20cm high and in active growth. From this it is clear, that the spray is to be directed to the leaves of the plants and not on the soil and that an active re-growth of the grasses is needed for the weedicide to work.

Also weeds heavily covered with dust from the soil are poorly effected by glyphosate, since this “dust” is soil and inactivates the chemical.

As such at initial land cleaning spray application is preferably done when sufficient rain is available to let the weeds actively re-grow and to make sure the weeds are not all covered with dust. The concentration is normally mentioned on the product label of the chemical, (like Rain bow 480 or Glyphosate 480 or Round-up 480 etc. which means 48% concentrate).

First strong killing effect of the spray shows after about 10 days to two weeks. After 3 weeks check fields on re-grown weeds and spot spray a same weed killer mixture again to obtain a total cleanup of all well-established weeds.

Although glyphosate kills all plants, it is most effective on monocots like all grasses, grain crops, sugar cane, and pineapple (these are all monocots). Glyphosate kills the pineapple.

Hexazinone mix with diuron as Valpar

Hexazinone; a selective herbicide and is systemic in activity. This herbicide is stronger than diuron and effective on weeds where diuron is too weak. However pineapple is also more sensitive to this chemical’s actions. Because of this stronger effect on pineapple it is used in lower concentration in pineapple, and often used in combination with diuron. It is on the market as a mixture of diuron and Hexazinone as Velpar K4 or Valpar Bromacil this weed killer is medium selective, and weak systemic in activity. Used at the right concentrations and applications, it has even a wider range of effect especially in the broad leaf weeds. Bromacil used to be traded as Hyvar X. Pineapple Production in Vanuatu - Trainers Guide

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Bromacil has a stronger negative effect on the pineapple itself than diuron and hexazinone. Bromacil is more persistent than Diuron or Hexazinone. Long after spraying its activity is still noticeable and accumulates in the soil for a long time.

Extra caution with the use of this herbicide is strongly advised. Pure bromacil is not commonly used and advised and mainly applied in a mixture if used in pineapple.

Atrazine; is another selective and systemic herbicide less commonly used in pineapple. It is stronger working than diuron and effects a wider range of broad leaf weeds. It does effect pineapple though just like bromacil and is a herbicide to choose only if the others do not work.

2-4-D; this weed killer is partly selective, systemic in activity. It works as a hormone.

This chemical works well on broad leaf weeds and to a lesser extent on grasses.

It is mainly absorbed through the leaves, although small amounts are also taken-up by the roots but at too low concentration to be effective. Overall the action is quite weak and high concentrations are needed to kill larger weeds. At too low strength this chemical only de-forms the plant, but does not kill it. It does have de-forming effects on pineapple, for which reason it is not used in pineapple cropping.

M.C.P.A.; this weed killer is strong selective, systemic in activity. It mainly effects broad leaf plants and has practically no effect on grasses. For this reason it is used widely in rice and corn cropping, on laws and turfs etc.However it is weak in protecting crops for a longer period from weeds, while it does not act on grasses at all.Therefore this chemical is not commonly used in pineapple.

Pre-plant weed control

To maintain a clean crop from the start of cultivation, planting has to be done on an absolute weed free field, including the absence of underground surviving roots of the larger grasses and root stock weeds. If the initial land has little to no large and deep rooted grass or tuberous root weeds, just once or twice deep turn-over operation with fork or spade of the soil or a few plough passes could be sufficient. But in most cases the grasses that are in the uncultivated fields are of the deep rooting type or the tuberous root type and hard to kill with only turning the soil with spade or plough.

Experience also shows that many broad leaf weeds develop after the field is turned over, from weed seeds stored for quite some time and deep in the soil.

There are a number of approaches to handle the pre-planting weed control operations, depending again on farming scale and availability of farming equipment & tools and finances.

The first approach is the use of only hand labor and manual tools. This system is only useful for small scale cropping and involves first clearing of a field the size intended for planting at present. First with farm knife and axe (or if available chain saw) large lumps of grass & weeds as well as shrubs and small trees are cut where needed. Then with fork and spade the root lumps of shrubs and large weeds are dug up and removed. The field which should be fairly clean and cleared now, is tilted and dug-up with spade and fork to at least 20 cm depth. This field is left in this state for about two weeks to give surviving weeds and dug-up seeds a chance of re-growth. After this re-growth the newly grown weeds are removed with Pineapple Production in Vanuatu - Trainers Guide

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digging hoe, dutch hoe or knife. This field is again left for one or two weeks to allow a weed re-growth, which is again removed and cleaned.

This field is now ready for final land preparation before planting. However it has to be understood, that this pre-planting cleaning is not thorough and after planting a fair amount of time has to be spend with frequent weeding. Soil disturbance with the farming tools also brings new weed seeds to the surface, which will germinate and grow.

This method is a high labour intensive job, but requires low financial input and is at the same time chemically clean, and rather environmentally friendly.

The second method is more suited for the larger “semi commercial” farms, using tractor or rototiller with limited use of chemical herbicides. This system provides a more thorough clean of the field from potential weed re-growth.

First the larger shrubs and small obstructing trees are cut with axe or chain saw. After this removal the field is raked with tractor or rototiller implemented rake to remove most of the larger weeds and grasses as well as left over stumps from shrubs and trees. When most of the rough growth is removed, the field is ploughed for the first time, basically to up-root the remainder of weeds and grass. This field is again raked with the available equipment. A second pass with the plough is now done with at least a 20 to 30 cm deep plough furrow.

Now this field is left untouched for two weeks to allow remaining weeds to re-grow, which is than killed with a none selective contact or systemic herbicide like “glyphosate” or “paraquat” to kill the remaining weeds with-out disturbing the soil too much. This spray of the herbicide is to be directed to the “green” part of the weeds, since it is inactivated when touched by soil or dust (heavy dust cover of the weeds make the herbicide less effective, best to wait until after a good rain shower). This field is now left for about two weeks to allow the herbicide to do its work, after which the field is ready for final land preparation and planting.

Although this system uses herbicidal chemicals, the effect on environment is very little, since this chemical only works in the weeds and is inactivated when it is coming in the soil. It has no persistence effect on soil or contaminating effect on deeper soil layers or water tables. The system requires less labour input but needs more capital investment in financial expenses for equipment and chemicals to be used.

The third method uses more herbicide sprays in combination with tractor or rototiller operated equipment. Here the large weeds are not first removed with rake equipment, but first completely killed with a strong and systemic herbicide spray.

A herbicide that destroys the complete weed including total root system is preferred, which has to be a strong systemic working chemical, like glyphosate.

Often a second spray is required after some time to kill also the last weeds that were not completely eliminated by the first spray and to kill any new weeds developed from seeds stored in the soil. This weed killer is to be given enough time to penetrate and kill the complete weed, in most cases this means waiting for around 3 weeks after spraying without burning or removing the dried-up aerial parts of the weeds.

Although seemingly dead and dried-out shortly after spraying, the chemical still has to penetrate in the still alive root tips to kill the total plant. If burned or pulled earlier, small portions of the roots remain alive and will produce again large and difficult to kill weeds, especially in cases of sedge and nut grass. After three to four weeks and if necessary, a second spray of weed killer is applied on re-growth of survived weeds and allowed to do its work for a few weeks to eliminate the remaining weeds. Now this field is ready for final fine tilth land preparation and preparation of beds for planting.

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Spray weed killer before land preparation

Post planting weed control

After planting has been done, the field is to be kept free from weeds, where mechanical weeding with tractor and equipment is not possible. As such hand weeding, mechanical hand weeding, and chemical sprays and are the only options left.

Here again two options are possible; The first option is only the use of hand pulling and mechanical weeding with hand tools combined with the use of mulch cover and no or very limited use of herbicides. This system is again more applicable for the small to medium sized plantations and involve a rather high amount of labour input. Because of the generally large amounts of weed seeds that start germination after strong soil disturbance, just after planting strong weed development is to be expected. This strong weed growth will be hard to control with only mulch cover and manual weeding operations. As such a single spray of â&#x20AC;&#x153;postplantingâ&#x20AC;? herbicides is generally advised, where the lesser persistent type of diuron is advised to control the first strong surge of seed weed growth. Than further control can be rather effective achieved with inter row mulch layers and regular manual weeding of combined hand pulling and use of cleaning with the dutch hoe. In this system for plant crop approx. 4 to 5 manual weeding operation are to be expected, with 2 to 3 renewals of mulch cover depending on mulch material used.

The second option is reliance on primarily herbicide application, which has to be combined with manual weeding. In this case a selective herbicide is to be chosen, which does not or hardly effects the pineapple plant, but which kills a large enough range of weeds. For this weed control in pineapple a choice of several herbicides can be made. Immediately after planting a selective herbicide is sprayed in between the planted pineapple row, covering the entire soil surface with equal spray cover, also in between the planted lines. Often shortly after this first spray (mostly about 3 weeks later, but only when new re-growth of weed seedlings are just starting to show) a second similar spray with herbicide is needed.

If not too heavy rain is experienced these two sprays should keep the planted blocks clean for 2 to 4 months, depending on strength of spray mix, type of herbicide and equal distribution of spray over the soil surface.

After this period some weed growth will have developed, which should the removed with a combination of hand pulling of large developed weeds and mechanical cleaning with dutch hoe or knife.

Immediate or at least soon after the hand weeding operations a herbicidal weed control spray is advised, especially in the wet, good growing periods of the year.

Combination of herbicide spray and mulch cover is less effective and not advised, since the chemicals will be for a large part be adsorbed by the mulching material and spray can drop in effectiveness to less than 40%.

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Herbicide sprays can be applied with a knapsack or a motor pump spray unit rather effectively and evenly.

Chemical spray in post-planting weed control

The herbicide used in post-planting weed control has to be strongly selective, which means it has no or hardly any effect on pineapple plants, but which has good effect on most of the occurring weeds.

The most commonly used are in increasing effectiveness, but also increasing persistence and environmental “unfriendliness; diuron, hexazinone, atrazine, and bromacil.

For this purpose Diuron is the first choice in chemical weed control of pineapple cropping. Diuron at the right concentrations and applications has no effect on the pineapple but prevents growth and kills at young stages the most common seed born weeds. It is to be realized however, that Diuron has no-to-little effect on “monocots” or grass like weeds, and these have to be eliminated at land preparation and before planting, or if coming up after planting by hand pulling or hand tool weeding.

If diuron has no or little effect on the weeds in the pineapple field hexazinone is used, which is stronger effective on a lot of weeds, also if a bit larger, but also has a stronger negative effect on the pineapple plant development and is more persistent or over a longer period of time effective in the soil (next crop and environmental issues). Mostly a combination of a mix of diuron and hexazinone is used in these cases (like the ready mix Velpar K4).

Only if these to combinations of herbicides are not working on the weeds in the pineapple plantation we can use a stronger herbicide like atrazine, which however has also a reducing development effect on the pineapple, and as a last resort use the strong and persistent herbicide bromacil, which is also strongly effective on pineapple.

These chemicals have all a rather long term working effect in the soil and could affect other types of crops (like cassava or dalo) planted at the same place even a year later.

So as such care and constrained in the use of the chemicals are advised especially towards the end of a complete cycle of pineapple cropping, when often weed development is also strong and a problem to keep under control.

Diuron can be effective for 2.5 to 4 months, depending on amount and frequency of rains, where with repeated heavy rain shorter interval between sprays are needed. Bromacil is even longer effective from 3 to 5 months. Best is to check regularly on newly sprouting weeds in the field. In cases of heavy weed growth all large weeds are first to be pulled by hand from in between the rows before herbicide spray is done. Try to avoid as much as possible to spray the mixture on the pineapple plants, in order to keep side effects as minimal as possible. If not too many large weeds preferably avoid use a hoe or other mechanical tool that might damage the pineapple roots close to the surface.

When the pineapple crop covers the major part of the beds and units with its leaves, then no spray is needed in between the beds and only the roads need regular “clean-up” sprays with broad activity herbicides like glyphosate or paraquat. Up to 3 - 4 sprays can be expected for a plant crop cycle and about 2 sprays for the ratoon crop cycle b before the pineapple crop covers the soil completely, however at heavy rainfall conditions more sprays might be required. Follow-up spray is applied with 80-120g of diuron/unit of 1000 plants as soon as early weed re-growth is noted.

Sprays can be applied with a motor-spray-pump-unit and tank on trailer + tractor or with a knapsack. The application rate per area is of importance and for a 1000 plants unit 80g to 150g diuron are needed, depending on thickness of weeds and heaviness of soil. The heavier the soil or more weeds, the higher the amount of diuron. Do not use too high concentration of the spray mix. Water is the carrier of the chemical and this water has to move the herbicide into the soil and towards the plant, so not too little water is to be used, even if it means a more work. Here a bit actual field experience will teach the right mix and quantity to be used.

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After this spray the soil should not be moved or mixed anymore, since the diuron or Velpar K4 forms a thin (about 2cm thick) blanket mixed with the soil to prevent weed seeds and young weeds to develop in this top layer. When this layer is disturbed by mechanical weeding or otherwise, the protective effect is gone on that place.

No herbicides are to be used in the field after flower initiation, natural or forced, since this will influence development and quality of fruit.

With the application of post planting herbicides like diuron, hexazinone, atrazine, and bromacil, care has to be taken that not too much is sprayed in total, meaning adding up all the follow-up sprays during a cycle, since all these chemicals are long persistent in the soil and stay long active especially when accumulated. Too high accumulated amounts will result in future crop growth decline, especially if other crops are planned for rotation in the same field, but also for pineapple if the accumulated amounts become too high. If in high concentration in the soil these chemicals might even effect ground water from which drinking water will be drawn or come with the ground water in fish ponds or rivers and effect fish populations.

Do not apply more diuron than 10 kg/ha before flowering of the plant crop or 25kg/ha for total crop cycles of plant crop and two ratoon over 4 year. And do not apply more bromacil or Velpar K4 than 6 kg/ha or before flowering of plant crop or 12kg/ for total crop cycles of plant crop and two ratoons over 4 year.

Other selective weed killers like 2.4.D and MCPA are effecting pineapple too much (causes deformation in the pineapple plant) and cannot be used in the pineapple cropping system. The same is for Fusilade, which is selective in broad leaf crops like beans and kills mainly grass-like plants (monocots), among which is also the pineapple plant.

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