Disease control: Getting the balance right

Disease control:

Getting the balance right

In mid-January, Adama held an online press brie ng to discuss its latest news and data relating to disease control. Rachel Hicks reports.

Opening the brie ng, Adama’s fungicides technical specialist Andy Bailey (right) gave a short market update. Of course, the dreaded Covid was mentioned, with Mr Bailey saying it continues to roll on – just as we think we’re coming out of it, it hits again. The face-to-face contact is being missed, with events still being a ected and screentime just isn’t the same.

He explained that last autumn was pretty horri c in terms of supply logistics – with problems getting product into port, then from the port into HGVs, from HGVs into warehouses and so on – due to Covid-19, driver shortages and other HGV industry issues.

However, he also pointed out that Adama is resilient, and has planned in advance as much as possible in order to ensure that spray programmes in spring 2022 won’t be negatively impacted. The marketplace was an extremely aggressive, dynamic place last autumn, with the Q4 Chinese production cessation ahead of the Winter Olympics 2022 in order to control air pollution, along with the usual decrease due to energy consumption policy leading to customers acting in more unusual ways. Meanwhile, pricing is evolving by the day from Q1 into Q2 for 2022.

Crops went into the ground in signi cant volumes in the autumn, with the winter wheat crop looking to be around 1.8 million ha in 2022, compared to 1.3 million ha planted in autumn 2021; and winter barley at 0.42 million ha compared to 0.3 million ha in the previous season.

In terms of 2021 disease management experiences in winter wheat, Mr Bailey said that many growers cut back fungicide inputs at T0 and T1 based on cool, dry conditions in early spring – even on some earlier drilled crops.

While it turned wet in May, it remained cool, which slowed crop growth and extended the gap between T1 and T2.

By T2, many crops still appeared disease-free on the upper leaves, but as it warmed up, latent infection developed which saw many crops carrying signi cant septoria pressure – especially where it continued to rain. This meant that disease management became much more of a curative situation rather than preventative.

The waning resistance in some varieties (notably those with Cougar in their parentage) was mentioned, which will need careful management moving forward, and Mr Bailey also posed the question: “With the loss of CTL, how many programmes included a multi-site?” This will have led to a lot of pressure on single site chemistry, particularly in T2.

Staying ahead of the game

“Beyond the use of resistant varieties and delaying drilling to reduce disease pressure, the over-arching key to e ective disease control in cereals is to stay ahead of infections,” explained Mr Bailey.

“This is best achieved by applying a diverse range of fungicide modes of action, with a multi-site such as Arizona (500g/litre folpet) included at the appropriate timing(s) to add an extra layer of disease control, protect single site actives from resistance and boost the crop’s yield potential by maintaining green leaf area for longer.”

When it comes to disease control, the importance is getting the balance right. Mr Bailey explained there are three primary elements that all need to be considered in order to make the best decision: • E cacy • Resistance management • Return on investment.

New eld trials carried out by Adama between 2018 and 2021 have shown that the inclusion of the multi-site fungicide folpet in spring spray programmes contributes to yield improvements of up to 0.6t/ha yield improvements of up to 0.6t/ha in winter-sown wheat and barley. in winter-sown wheat and barley.

The trials indicated that the The trials indicated that the inclusion of Arizona, alongside inclusion of Arizona, alongside single site fungicides, enables single site fungicides, enables wheat and barley crops to stay wheat and barley crops to stay ahead of key diseases including ahead of key diseases including septoria and rhynchosporium septoria and rhynchosporium (as well as providing (as well as providing valuable protection valuable protection against ramularia – against ramularia – although this is not although this is not currently indicated currently indicated on the label so is anecdotal only at this anecdotal only at this stage) and ensures stage) and ensures each successive leaf each successive leaf stays greener for longer. stays greener for longer. “Sustainable disease control is about achieving the right balance in terms of fungicide e cacy, resistance management and return on investment,” Mr Bailey continued. “Across a total of 29 wheat trials, a single application of Arizona at T1 more than paid for itself by giving an average yield uplift of 0.26t/ha. When applied at two spray timings this yield response increased to as much as 0.6t/ha when used alongside older single site fungicides and by a more modest but still respectable 0.2–0.25t/ha when used at two spray timings in conjunction with newer single site actives such as Revysol and Inatreq.”

A two-spray inclusion strategy also gave the best results in barley, where the yield response ranged from 0.3–0.6t/ha.

“Arizona can deliver a signi cant yield improvement and represents a viable return on investment,” added Mr Bailey, who explained that T1 is the key timing for the inclusion of folpet in wheat programmes. “In high-risk wheat situations – for example where a susceptible variety which was drilled early and is growing in wet conditions in an area with a high disease loading – folpet can also be applied at T0 and/or T2 as the season dictates.

“In winter and spring sown crops of barley, T2 (GS39/49) is the key timing for including Arizona, with a two-spray approach at T1 and T2 giving the best results.”

The inclusion of folpet in spring fungicide programmes is also endorsed by FRAG-UK (Fungicide Resistance Action Group) which it describes as a “valuable tool to manage resistance by preventing development to many pathogens [...] which can protect and prolong the lifespan of medium to high resistance risk fungicides like SDHIs [...] and which provides added levels and spectrum of disease control”. FG

Supporting your crop protection decisions

The latest edition of the British Crop Production Council’s UK Pesticide Guide 2022 is available to purchase now.

Technical and business errors in farming can come at a high cost. The stakes are expected to get higher as our industry comes to terms with new legislation, changing the direction of UK farming from one of progressive intensi cation seen over the past 50 years, to one based on sustainability; with any support aligned to the provision of public goods focused on the environment. Understanding the technical and business issues which could help protect future pro tability is vital. Having the business tools and science-based factual information to make the most appropriate decisions is essential.

When it comes to making those decisions, help is at hand in the form of the BCPC’s UK Pesticide Guide 2022, available in print and online. Familiarly known as the Green Book, it is the independent, authoritative reference for all pesticide products and adjuvants approved for use in agriculture, amenity, forestry and horticulture, and a vital resource for sprayer operators, farmers, advisors, agronomists, and industry professionals.

For arable and mixed farms, safeguarding pro tability will include all aspects of crop husbandry to reduce production costs and improve competitiveness. Not least of those, given the renewed interest in integrated crop management, is understanding the rapidly changing use and availability of crop protection products.

So, when it comes to making those technical decisions surrounding the complex and potentially costly issues of crop protection, the UK Pesticide Guide 2022 is likely one of the best investments you can make this year.

To order your copy, email publications@bcpc.org or visit www.bcpc.org FG

The Online UK Pesticide Guide

Experience the industry-leading online search and comparison tool

Subscribe to the 2022 Online UK Pesticide Guide – a practical guide to pesticides, plant growth regulators and adjuvants that can be legally and effectively used in agriculture, horticulture, forestry, amenity and pest control sectors in the UK. The tool is designed to support your crop protection decisions and has:

•Improved functionality and user experience •In-depth product information and links •Option to compare and filter thousands of products •Access via PC and tablet •Content updated regularly •A flexible and easy to use format

Subscribe online at www.ukpesticideguide.co.uk