R4D Review Edition 5, September 2010 The time is now The quiet revolution Anyone for cowpea? The spice of life Molecular tools for Striga-resistant cowpea Cowpea in Serbia Enriching livestock diets All about the bag To conserve or not to conserve? Joining hands against pod borer Is mechanization the solution? New approaches to assess soil conservation Researcher inspecting cowpea flower, IITA demo farm. Photo by J. Oliver, IITA.
www.iita.org
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EDITOR’S NOTE
The time is now Cowpea, or black-eyed pea, is one of those crops that could influence the nutritional status in sub-Saharan Africa. Now is the time to fully harness its potentials for enhancing health and nutrition, and ensuring livelihoods.
SPECIAL
4 5th World Cowpea Conference aflasafe™: a winning formula Bacterial wilt-resistant banana Battling cassava disease
The quiet revolution 6 B.B. Singh, the former cowpea breeder at IITA (1979 to 2006), discusses the highlights of research in cowpea improvement over the last four decades and suggests future directions to expand its cultivation as a niche crop.
10 features
Anyone for cowpea? 10 Rarely in the limelight, cowpea needs a little help to step out of the shadows and become a household name. This insider information provides some general and unique information about this remarkable crop. Diversity: the spice of life 12 Molecular geneticist Sarah Hearne emphasizes the importance of characterizing genebank collections for use in selecting the best materials for crop improvement. One such study confirmed the robustness of the Institute’s collection on cowpea. Using molecular tools to develop Striga-resistant cowpea 14 Marker-assisted breeding could help hasten the development of cowpea varieties resistant to Striga, a parasitic weed that causes millions of dollars worth of losses every year.
Cowpea and other Vigna species in Serbia 17 Not many people know that cowpea grows in the Balkans, which has a typical temperate climate. The author, Aleksander Mikic, explains what Serbia is doing to exploit the potentials of cowpea and other pulses. Enriching livestock diets with cowpea 20 Cowpea is not just for humans; it is also grown for fodder. Thus, improving the nutritional quality of crop residues is important to enhance the productivity and profitability of mixed crop-livestock systems, explains ILRI scientist Elaine Grings. All about the bag, not the bug 22 What is the “magic” behind the triple layer plastic bag developed by Purdue University? Learn what PICS is doing to promote this costeffective technology for hermetic storage of cowpea seeds, and how the value chain development is helping farmers and entrepreneurs alike. To conserve or not to conserve? 24 IITA’s Genetic Resource Center has the biggest collection of cowpea accessions from 89 countries, mostly in Africa, and has distributed germplasm to research institutions in many parts of the world. What has been the impact of this work and at what cost? This study attempts to provide answers to this and other questions.
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BEST PRactice Joining hands against the pod borer 30 IITA and partners continue to collaborate on research that would control the Maruca podborer, a major pest of cowpea in the field. IITA Legume Entomologist Manuele Tamò describes the ongoing work on developing this biocontrol technology.
Improved cowpea varieties for Nigeria's savannas 33 Nigeria has released two new cowpea varieties for the savannas. These improved varieties were developed by IITA and local partners to increase production and improve farmers’ incomes.
Conserving cowpea using GIS tools 34 With the use of GIS tools, researchers were able to get an overview of the actual distribution, agroclimatic preferences, and potential distribution of cowpea. More importantly, they identified gaps or areas that are underrepresented in IITA’s cowpea collection, and that need to be given priority for biodiversity conservation. Is mechanization the solution to cowpea's woes? If Nigeria wants to increase cowpea production, it needs to mechanize existing tools and promote efficient farm management techniques, argues Postharvest Engineer Thierno Diallo. Mechanization may not be the only solution but it can certainly help the millions of farmers in subSaharan Africa become more productive.
40 who’s who Victor Manyong: Strengthen socioscience capacity
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How to fast-track cowpea breeding 39 An IITA researcher, with partners, has constructed a linkage map for cowpea and identified portions on the cowpea genome that have effects on drought tolerance and resistance to bacterial blight. Such molecular tools would considerably shorten the plant improvement process from 10 to 3 years.
46 looking in Irvin E. Widders: Perspectives on CRSP training
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Ousmane Boukar: Cowpea improvement for food security and poverty alleviation 43
James M. Lowenberg-Deboer: Ensuring Africa's future through agriculture 49
52 f r o n tiers Approaches to assess soil conservation GIS tools could help governments, policymakers, and land use planners to manage their environments better by providing information on land degradation and use. Such information is useful for monitoring and for devising a strategy for natural resource management and conservation.
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Trivia 28 Recipes 29
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EdITOR'S NOTE The time is now
Cowpea, or black-eyed pea, is one of the few crops that could positively influence the nutritional status in sub-Saharan Africa. Grown by farmers mostly in West Africa, it is increasingly gaining prominence in the fight against hunger and poverty. This is reflected in its dual roles as a source of protein for humans that is cheaper than animal products and a way to raise the quality of livestock through improving their feed. Cowpea also provides higher returns on investment than other crops grown in the region where it thrives best. Unfortunately, support for cowpea research has been relatively low, unlike that for other crops such as wheat and potatoes. Consequently, this has limited the improvement of cowpea. The situation is not being helped by the negative impact of climate change and
unfavorable abiotic factors in the regions where the crop is mostly grown. Over the years, IITA and its international and local partners have developed solutions to tackle the constraints faced by this “wonder” crop. These include the development and deployment of improved, Striga-resistant, drought-tolerant, and early maturing varieties. More recently, work is ongoing to produce varieties resistant to the damaging legume pod-borer (Maruca). The impact of these varieties on rural livelihoods and poverty is slowly but surely being felt. Advances in science could help to further raise cowpea yield. With more resources now going into cowpea research and farmers' participation in variety selection, even better performing varieties should be available soon. These efforts have already produced positive results in the target regions but only on a relatively small scale when set in the context of all sub-Saharan Africa. The task before stakeholders is to join hands with IITA now to advance this crop and to save Africa. The time to act is now.
“The future of cowpea in Africa depends on maintaining and developing a research community that will allow this species to fulfill its potential.
- James M. Lowenberg-DeBoer, Purdue University
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For too long, a versatile crop, capable of providing huge benefits for health and wealth stayed on the sidelines, largely below its economic potential and comparatively neglected by research. More recently, however, interest in this grain legume has greatly increased and its benefits have been more widely appreciated and publicized.
Close-up of a cowpea flower in full bloom, IITA demo field. Photo by Christine Peacock.
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news 5th World Cowpea Conference
Scientists are meeting in Saly, Senegal, this month for the Fifth World Cowpea Research Conference. The meeting will discuss threats to the survival and production of black-eyed peas—one of Africa's oldest and most resilient and nutritious crops. They will also discuss key constraints to cowpea production, share progress being made in advanced cowpea genomics, and consider the best ways to unlock cowpea's potential as a hedge against climate change, hunger, and poverty. IITA is hosting the World Cowpea Research Conference with the Government of Senegal, the Dry Grain Pulses Collaborative Research Support Program, and Purdue University. Among the issues to be discussed:
• Rescuing cowpea from extinction: Progress on global efforts to rescue the cowpea gene pool. • "Designer" peas: State-ofthe-art genetic research to develop "designer," insectresistant black-eyed peas. • Cashing in on cowpea: Improved varieties offer a pathway out of poverty. • Cowpea genemap: Update work to produce a new genetic map for cowpea to accelerate efforts to breed improved varieties. • Biological controls for cowpea pests: Using
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genomics tools to develop and deploy biocontrol agents to manage insect pest populations. • Green-er farming: How farmers are using cowpea as "green" fertilizers to revitalize degraded soils, and use crop waste as energy-rich feed for cows, sheep, and goats. • Postharvest: Millions of African farmers are using hermetic storage without insecticides to safely store cowpea. • Cowpea-based food entrepreneurship: Cowpea-based street foods provide income for thousands of women in West and Central Africa.
aflasafe™: a winning formula Biological control of aflatoxins using aflasafe™ is providing hope for African farmers battling with crop contamination and opening doors for the private sector looking to invest on a winning formula in the agricultural sector. Scientists have developed a cost-effective, safe, and natural method to prevent aflatoxin formation in maize while in the field. Aflatoxin causes liver cancer and suppresses the immune system, endangering both humans and animals. It also retards growth and development of children. This colorless chemical is invisible and its presence and contamination levels can only be confirmed by laboratory tests. The biocontrol technology works by introducing native (local) strains of the
fungus Aspergillus flavus that do not produce the aflatoxin (the ‘good guys’) in the affected fields. This good fungus boxes out and drastically reduces the population of the poisonproducing strains (the ‘bad guys’). The aflasafe™ technology has the potential to provide relief to millions of maize farmers in sub-Saharan Africa depending on agriculture as a source of livelihood. According to Ranajit Bandyopadhyay, IITA Plant Pathologist, a single application of this biopesticide 2-3 weeks before maize flowering is sufficient to prevent aflatoxin contamination throughout and beyond a cropping season and even when the grains are in storage. With an initial investment outlay of US$1−3 million in an aflasafe™ manufacturing plant, investors are likely to reap about $1.33 million annually. Bandyopadhyay said that investing in an aflasafe™ manufacturing plant in Nigeria would pay off considering the huge demand for quality maize in the country. His estimates showed that over 60% of harvested maize in Nigeria currently has high levels of aflatoxins and are prone to being rejected by the feed industry. Institutions involved in the initiative include IITA, Agriculture Research Service of the United States Department of Agriculture, AATF, and local partners.
Bacterial wiltresistant banana Crop scientists have successfully transferred genes from green pepper to banana that enable the crop to resist the Banana Xanthomonas Wilt (BXW). BXW or bacterial wilt is one of the most devastating diseases of banana in the Great Lakes region of Africa. It causes about half a billion dollars worth of damage yearly. The transformed banana, infused with plant ferredoxin-like amphipathic protein (Pflp) or hypersensitive responseassisting protein (Hrap) from green pepper, have exhibited strong resistance to BXW in the laboratory and screenhouses. The Hrap and Pflp are novel plant proteins that give crops enhanced resistance against deadly pathogens. They work by rapidly killing the cells that come into contact with the disease-spreading bacteria, preventing them from spreading any further. They can also provide effective control against other BXWlike bacterial diseases in other parts of the world such as “Moko”, Blood, and “Bugtok”. The genes used in this research were acquired under an agreement from the Academia Sinica in Taiwan. The mechanism is known as hypersensitivity response and activates the defense of surrounding and even distant uninfected banana plants leading to a systemic acquired resistance.
Scientists from IITA and the National Agricultural Research Organization of Uganda, in partnership with African Agricultural Technology Foundation, would soon be evaluating these promising resistant lines under confined field trials after the Ugandan National Biosafety Committee recently approved the conduct of the tests. Presently, there are no commercial chemicals, biocontrol agents, or resistant varieties that could control the spread of BXW. Developing a truly resistant banana through conventional breeding would be extremely difficult and would take years, given the sterile nature and long gestation period of the crop.
Battling cassava disease The cassava brown streak disease continues to threaten the food security and livelihoods of over 200 million people in East Africa. It causes greater economic damage than the mosaic disease as it destroys the more valuable part of the crop—the roots. The disease had previously been confined to lowland coastal areas in East Africa, but the new outbreak has spread rapidly to the high altitude regions (over 3000 feet above sea level) of Uganda, Kenya, and Tanzania around the shores of Lake Victoria. Almost three-quarters of the population of Zanzibar
rely on agriculture for food and income, with cassava being the second most important staple after rice. Over 90% of the island’s subsistence farmers grow cassava. Zanzibar scientists and IITA, with support from the Rockefeller Foundation and other partners, bred new cassava varieties to combat the brown streak menace. In 2007, the national agricultural system released four tolerant varieties that yield twice as much as the local varieties while satisfying local preferences such as taste and cooking texture. They have been welcomed by the farmers. Currently, the challenge is to get enough planting materials to meet the demand. Only 10,000 cassava farmers out of almost a million on the island are growing the improved varieties. The government, IITA, and several development partners and donors such as the Alliance for a Green Revolution in Africa have been engaged in efforts to rapidly multiply these varieties to ensure that they are available to as many farmers in the shortest possible time. Efforts are also under way to identify suitable varieties for neighboring countries and in the mid-altitude zones of Tanzania. Already, more than 15 varieties have been identified in Uganda and Tanzania that show acceptable tolerance levels even under the harshest conditions of disease pressure. They are expected to be released in a year or two after further testing.
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The
quiet revolution
B.B. Singh, drbbsingh@yahoo.com Cowpea was a relatively minor tropical legume about 50 years ago, but it is now emerging as one of the most important food legumes in the 21st century because of its early maturity and ability to fit as a niche crop in multiple cropping systems. There has been more than a 6-fold increase in the world cowpea production in the last few decades—a quiet revolution that is greater in magnitude compared to that of cereals and all other pulses. Based on FAO data and correspondence with scientists in different countries, annual cowpea production has increased from about 0.87 million tons in 1961 to 1.2 million tons in 1981 to 2.4 million
tons in 1991, to more than 6.3 million tons in 2008. The major increases have been in Niger, Nigeria, Mali, Burkina Faso, Senegal, Tanzania, Uganda, Congo, Myanmar, India, and Brazil. These successive increases in cowpea production over time have occurred due to the concerted efforts and coordinated cowpea research and development activities of IITA and its national, regional, and international partners over the last four decades and the release of new improved short-duration cowpea varieties in different countries. It is expected that cowpea production will significantly increase in the coming decades also as more shortduration and pest-resistant varieties
Women farmers growing 60-day cowpea in Nigeria. Photo from B.B. Singh.
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become available and cowpea cultivation makes further inroads as a niche crop in the cereals and root crops-based systems. Significant advances in cowpea research Cowpea originated in the southern African region several thousand years ago and spread to the different parts of the world covering over 65 countries in Asia and Oceania, the Middle East, Southern Europe, Africa, Southern USA, and Central and South America. The nitrogen-fixing crop with great versatility was entrenched into local cropping and food systems. It was given indigenous names such as ‘lobia’ in India, ‘kunde’ in east Africa, ‘beans’ and ‘wake’ in Nigeria, ‘niebe’ in francophone Africa, ‘southern pea’ and ‘blackeye pea’ in the USA, ‘feijão caupe’, in Brazil, and a host of other names in different countries around the world. Its nutritious young leaves, green pods, green seeds, and dry grains are used in various food preparations, while the nutritious fodder is fed to livestock and the crop residue in the field contributes to improved soil fertility.
Improved 60-day cowpea in northern India. Photo from B.B. Singh.
for Africa (NGICA) has further strengthened cowpea research in the region.
Limited efforts in cowpea improvement began in a few countries in the 1960s but it was the establishment of IITA in 1967 that gave cowpea some well-deserved attention. IITA actively collaborated with its NARS partners in catalyzing and supporting research on cowpea improvement and distributing improved cowpea materials.
The major successes include a collection and use of over 15,000 germplasm lines and development of a range of improved varieties with diverse maturity, plant type and seed type combined with high protein, iron, zinc, and resistance to major biotic and abiotic stresses. Using a combination of field and laboratory screening, several varieties have been developed with combined resistance to cowpea yellow mosaic, blackeye cowpea mosaic, and many strains of cowpea aphid-borne mosaic, Cercospora, smut, rust, Septoria, scab, Ascochyta blight, bacterial blight, anthracnose, nematodes, Striga, Alectra, aphid, thrips, and bruchid.
Cowpea research received another boost when the USAID-funded Bean/ Cowpea CRSP (now The Dry Pulses Project) became operational in the 1980s as it complemented IITA’s efforts in strengthening cowpea research and development in Africa. The recently established Network for Genetic Improvement of Cowpea
Similarly, using simple screening methods for tolerance for heat, drought, and low P, major varietal differences for all the three traits have been identified and incorporated into improved varieties. Also, varieties with 30% protein and enhanced levels of iron, zinc, and other micronutrients have been identified.
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Joint efforts are being made by IITA, The Dry Pulses project, advanced laboratories in the USA and Australia, African Agricultural Technology Foundation (AATF), NGICA, and Monsanto Corporation to exploit biotechnological tools and complement conventional methods for improving insect resistance in cowpea. Efforts are also under way to develop markers and protocols for marker-assisted selection (MAS) for Striga resistance and other traits in cowpea.
developed which yield over 2.5 t/ ha grain and over 3 t/ha fodder in 75–80 days. These varieties have been tested and based on their good performance, over 40 improved varieties have been released in 65 countries covering Africa, Asia, and Central and South America.
The new varieties have been given specific and interesting names such as ‘Big Buff’ (IT82E-18) in Australia; ‘Bira’ (TVx 3236) in Angola; ‘Titan’ (IT84D-449) and ‘Cubinata’ (IT84D-666) in Cuba; ‘Asontem’ (IT82E-16), ‘Ayiyi’ (IT83S-728-13), Development and release of and ‘Bengpla’ (IT83S-818) in Ghana, improved varieties Using the vast genetic pool and useful ‘Akash’ (IT82D-752) (sky) and ‘Prakash’ (IT82D-889) (light) in genes already identified, a great Nepal; ‘Sosokoyo’ (IT84S-2049) in deal of progress has been made in Gambia; ‘Pkoko Togboi’ (IT85F-867-5) breeding a range of high-yielding in Guinea Conakry; ‘Korobalen’ cowpea varieties with combined (IT89KD-374) and ‘Sangaraka’ resistance to major diseases, insect pests, Striga and Alectra, and drought (IT89KD-245) in Mali; ‘Dan IITA’ (TVx tolerance. Combining erect plant type 3236) (son of IITA) and ‘Dan Bunkure’ (IT89KD-288), IT90K-76, IT90K-82-2, with early maturity and resistance to IT90K-277-2, and IT93K-452-1, in major pests, several new extra-early cowpea varieties have been developed Nigeria; ‘Melakh’ and ‘Mouride’ in Senegal; ‘Pannar 31’ (IT82E-16) which yield up to 2 t/ha within 60 in South Africa; ‘Dahal Elgoz’ days compared to <1 t/ha in local varieties, which mature in 100 to 140 (IT84S-2163) (gold from the sand) in Sudan; ‘Umtilane’ (IT82D-889) in days. Swaziland; and ‘Bubebe’ (IT82E-16) Similarly, several medium-maturing in Zambia; ‘Vamban 1’ (IT85F-2020), dual-purpose varieties have been ‘Pant Lobia-1’ (IT98K-205-8), and ‘Pant Lobia-2’ (IT97K-1042-3) in India; and many more.
Improved cowpea-sorghum strip cropping system. Photo from B.B. Singh.
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Cereals-cowpea intensive cropping systems in the tropics With support from USAID, UK Department for International Development (DFID), GATSBY Foundation, Danish International Development Agency (DANIDA), Canadian International Development Agency (CIDA), and others, several improved intensive cowpea-cereals cropping systems have been developed. The improved strip cropping system involving two rows of cereals and four rows of cowpea has enabled farmers in Nigeria and
60-day cowpea in wheat-rice system in northern India. Photos from B.B. Singh.
Niger to produce one to two cowpea crops in the same season while maximizing the cereal yields. Similarly experiments conducted using 60day cowpea varieties in northern Nigeria and India have demonstrated successful triple cropping involving â&#x20AC;&#x2DC;wheat-cowpea-riceâ&#x20AC;&#x2122; each year. The additional cowpea crop in the summer season after the wheat harvest not only provides extra employment but it also improves soil fertility and provides nutritious food grain and fodder. Future outlook In the wake of increasing global warming and declining rainfall and water table, it is expected that cowpea production will increase in the future using heat- and droughttolerant 60-day cowpeas as a niche crop in the cereals and root crops systems covering millions of hectares in Asia, Africa, and the Americas. Northern India alone has about 10
million ha under wheat-rice system. An additional crop of 60-day cowpeas as a niche crop between wheat and rice can produce between 10 to 15 million t of cowpea which would double the current pulses production in India. A similar possibility exists for double cowpea cropping in several parts of Africa and wheat-cowpea double cropping in southern United States covering several million hectares. Brazil is adding thousands of hectares of new land each year under cowpea cultivation. Thus, there is a need to develop a diverse set of region-specific and niche-specific varieties to expand cowpea cultivation in the world and help improve family food security and nutrition. Contact details: B.B. Singh, Visiting Professor Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77840, USA
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features
Anyone for cowpea? The cowpea is not actually a pea but a little bean that has a huge range of remarkable attributes and properties. Despite being a staple food to millions of people, this unassuming crop does not have the global profile it deserves. Did you know that the cowpea is actually one of the oldest domesticated crops known to the human race? It is believed to have originated in West Africa between five and six thousand years ago where it was associated with ancient cereal farming. From Africa it was taken around the world by merchants, travelers, and most notably by slaves. Between the
16th and 19th centuries, millions of people were transported across the Atlantic. Many of them ended up in the southern United States. The cowpea was brought with them and became a staple of African American cookery, which is often called “soul food”. Today the cowpea is grown on over 10.1 million ha across the globe (FAO 2008). Africa produces almost 5.2 million t of the global total of 5.4 million t of dried cowpea. Nigeria is the world’s largest producer, generating 58% of the worldwide yield. The cowpea is rich in several vitamins, minerals, and especially protein, which makes it a key crop in poverty-stricken areas because it can be used as a replacement for meat. More than 4 million t of cowpea are consumed worldwide each year. In Africa alone, 387,000 t are eaten. In East Africa, the leaves are often used rather like spinach, in soups and stews. In Asia and Latin America, the green seed pods, similar to runner beans, are eaten as a vegetable. The seeds, though, are the main food product from the cowpea plant. They can be dried, used fresh, or cooked, then canned or frozen. The beans are often served with rice but can also be added to other meals. In Nigeria, cowpea is used to make akara, a savory fried donut and moin-moin, a steamed bean cake.
Improved cowpea variety, IITA, Nigeria. Photo by IITA.
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However, it is not only humans that enjoy the crop. The plants are also used as animal fodder. The stems,
leaves, and vines can be harvested and given to livestock fresh but are more commonly dried and turned into hay or silage. In West Africa, cowpea hay is a significant source of income for farmers during the dry season. On top of being an incredible food product, cowpea is resistant to drought and easily adapts to different soils while growing intercropped with other plants, such as yam, maize, or millet. This makes the crop easy to grow, even for small-scale farmers. As a legume, cowpea acts as a green manure, replenishing the nitrogen in the soil and increasing land fertility. The crop also maintains the land by growing quickly and covering fields, deflecting the rain with the leaves, and preventing erosion. Itâ&#x20AC;&#x2122;s not all plain sailing for the versatile cowpea. Pests, such as aphids and bruchid weevils attack the cowpea plant during its life cycle; it is also damaged by bacteria, fungi, and viruses that cause diseases such as Cercospora leaf spot, a fungal infection on the leaves. Other problems that the cowpea can face come from nematodes in the ground that inhibit the roots and parasitic weeds that grow up around the plant and eventually choke it. IITA and its partners have made a significant breakthrough with this plant. They have created varieties with better disease and pest resistance and some with consumer-preferred traits, such as being easier and faster to grow, high yielding, and having seeds of a specific size, texture, or color. In addition there are varieties that actually shorten the processing because they are easier to cook and
peel. These modified varieties have been distributed to over 68 countries across the globe. IITA has also made major steps in collecting and categorizing the worldâ&#x20AC;&#x2122;s largest collection of cowpea germplasm in its genebank. The diverse collection represents 70% of African examples and just under half of those found globally. At the Fifth World Cowpea Research Conference, taking place in Senegal from 27 September to 1 October 2010, scientists from around the world will meet to tackle various issues surrounding the crop. Not least of these is to promote the versatile cowpea from being a less well-known extra to a main player on the world stage. So, anyone for cowpea? Reference http://faostat.fao.org/site/567/default.
Cowpea market vendor, Ibadan, Nigeria. Photo by IITA.
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Diversity: the spice of life Sarah J. Hearne, s.hearne@cgiar.org Cowpea is an important grain legume cultivated globally in the treescattered open grasslands of the tropics and subtropics. In Africa, these characteristic savanna regions are the â&#x20AC;&#x153;birthplaceâ&#x20AC;? of cowpea. The center of diversity of wild cowpea (where you find the most variation) is in southern and southeastern Africa; the center of diversity of cultivated cowpea is in West Africa (Padulosi 1993). As a crop, cowpea is generally grown for its dry grain used for human and animal consumption, and green pods consumed as vegetables, and also for the fiber for textiles from the long peduncles or stalks (West Africa). It is a versatile plant and is used as a green manure, a dual-purpose crop in mixed cropping systems, and alone as a forage crop for livestock. The leaves are also eaten as a vegetable in parts of East Africa and in Senegal; in Sudan and Ethiopia, the roots are eaten as well. IITA holds more than 15,000 accessions of cultivated cowpea in its genebank collection. These accessions form an
invaluable resource for conservation and improvement. To be able to fully use such a collection, it is important to characterize the materials to enable the selection of the best materials for various purposes, such as crop improvement for high yield, better agronomic traits, drought tolerance, or disease resistance. To help characterize IITAâ&#x20AC;&#x2122;s global cowpea collection, Institute scientists undertook a study funded by the Generation Challenge Program. This included defining a core collection from the thousands of accessions held in the IITA genebank, characterizing the molecular diversity of this collection, and defining a smaller reference collection to enable the wider use of these important genetic resources. Seeds of the core collection accessions were virus tested and have been made available for distribution. A core collection is a subset of accessions that are representative of the diversity of the entire collection. These core collections are needed as they
The cowpea seed collecion, IITA genebank. Photo by J. Oliver, IITA.
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USA 6%
India 23% Africa 71%
Cowpea collection sites
provide a smaller, more manageable number of materials from which meaningful conclusions reflecting the wider collection can be made. A core collection of 2,062 accessions was derived from the 15,000 accessions in the IITA genebank, based on information held on each accession within the genebank database. The core collection contains accessions from many countries but with more from West, East, and Central Africaâ&#x20AC;&#x201D;the cradle of cowpea diversity. The core collection was then subjected to further study. Molecular markers, signposts present in the DNA of all living things, were used to look for variation among the accessions in the laboratory. Using the resulting data, scientists were able to describe the molecular diversity of the accessions and identify which accessions were more like one another and those that were not. As a result, clusters of accessions that were similar to one another could be identified. Altogether, nine such clusters were identified in the cowpea core collection. The core collection is an important resource, but it is simply too large for many users of the genebank to apply in studies, such as screening
for desired traits (perhaps disease resistance) in a systematic manner. It was therefore necessary to define from the core a smaller collection of accessions, called a reference collection. The reference set of 374 accessions was defined using the clusters identifed in the molecular characterization. The reference collection is representative of the molecular diversity and descriptive diversity of the core and the entire collection. As soon as the definition of the cowpea reference collection was publicized the genebank received many requests for the materials. The reference collection has been used widely by IITA scientists and our many partners and genebank clients in studies looking at drought, pest and disease tolerance, and in further studies of molecular diversity. The robustness of the collection was confirmed during some of these studies when comparisons of the reference collection with those from other institutes indicated that there was no novel molecular diversity present in the other collections investigated. Reference Padulosi, S. 1993. Genetic diversity, taxonomy, and ecogeographic survey of the wild relatives of cowpea (V. unguiculata). PhD thesis. University of Louvain La Neuve, Belgium.
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Using molecular tools to develop Striga-resistant cowpea Witchweed, Striga gesnerioides (Willd.), continues to be a major menace to production in West and Central Africa, where cowpea is an important crop.
farmers to articulate their problems and preferences, and tested new Strigaresistant improved lines developed using MAS.
This parasitic weed feeds on cowpea plants, leading to severe chlorosis or yellowing, wilting, stunting, and even the death of susceptible hosts. Annual yield losses are estimated in millions of tons.
Prior to the breeding activity, participatory rural appraisal (PRA) and farmers’ participatory variety selection (FPVS) sessions were organized in seven Striga hot-spots in Niger and Burkina Faso, which are major cowpeaproducing areas. During the 2 years, in Niger, 403 farmers contributed to the FPVS and several of their preferred cowpea lines were selected.
Collaborative project A collaborative project funded by the Generation Challenge Program has taken a close look at the Striga problem and is using molecular tools to identify new sources of resistance. Marker-assisted selection or breeding (MAS or MAB) is being used to facilitate the selection of lines with resistance to Striga. In 2008 and 2009, the Institut National de l’Environnement et des Recherches Agricoles (INERA) of Burkina Faso and IITA undertook a study to identify potential sources of Striga resistance, worked with
Striga-infested maize field. Photo by IITA.
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To determine farmers’ preferences in Niger, germplasm of 24 cowpea varieties with various characteristics (seed color, seed size, plant type, maturity, and Striga resistance) were planted in farmers’ fields and used for the PRA and FPVS. The same 24 accessions were also planted in two fields at IITA’s Minjibir Experimental Farm as checks. In Niger, researchers and local agricultural agencies worked with farmers in their fields. Based on interviews and responses to questionnaires, farmers acknowledged that Striga is a serious problem that seems to be increasing, said IITA scientists Satoru Muranaka and Ousmane Boukar, and Jean Baptiste Tignegre of INERA, who collaborated on the project. Farmers, they added, also suggested that the use of resistant varieties could be a solution. This reconfirmed the importance of Striga resistance as a breeding goal. The project has also confirmed farmers’ preference for IT00K-1148 and IT90K-372-2-1 because of their agronomic traits. These lines are susceptible to the dominant race of Striga in Niger. In the FPVS, farmers preferred new lines, such as KVX30-
Trial sites for 2009 FPVS activities in Niger and Nigeria.. 309-6G and TN256-87, which also lacked resistance to Striga. Of the top five genotypes selected by the farmers in the seven locations, only two—IT99K-573-2-1 and IT98K-2058—were picked by farmers because these met their preferences for Striga resistance, early maturity, and high yield potential.
Both IT99K-573-2-1 and IT98K-205-8 showed resistance to Striga in all the locations used for the trial. These varieties could be recommended for cowpea production in Southeastern Niger where Striga and drought are major constraints, and for use as sources of resistance genes in breeding other varieties.
Farmers preferred the white-seeded variety for consumption but genotypes with brown seed color that are early maturing and high yielding were also acceptable. The surveys and FPVS activities showed that farmers use consistent selection criteria based on various traits.
Marker-assisted breeding Using MAB, pot and field experiments in 2008 and 2009 evaluated backcrossed varieties (crossed to their parents) for various traits, such as resistance to Striga, flowering and maturing dates, disease resistance (to bacterial blight, virus, and leaf rust), and seed characteristics.
Because of unstable rainfall and other problems in 2009, farmers did not get good grain yields, although in a few cases, Striga-resistant IT99K-573-2-1 showed 4−6 times more grain yield (average 214 kg/ha compared with 37−51 kg/ha for local varieties).
Of the 60 genotypes tested in a pot screening trial in the Maradi station of the Institut National de Recherche Agronomique du Niger (INRAN) from October 2008 to November 2009, 18 showed Striga resistance. Results
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confirmed that the Striga race (SG3) dominant in two locations in northern Nigeria is also dominant in the four trial locations in southeastern Niger. Field trials had been conducted earlier in Kano and Borno States in Nigeria. Hence, the same Striga-resistant genetic resources could be used for breeding varieties for these areas. Two existing sequence characterized amplified region (SCAR) markers, 61R and MahSE2, were earlier identified to have the potential for use in MAB for SG3 Striga resistance. To confirm this, pot experiments were conducted using Striga-resistant lines that had been developed using MAS. Results showed a higher percentage of resistant plants in the MAB-developed populations than in the control (those that did not use MAB). SCAR marker MahSE2 showed 88% and 96% marker efficiency for evaluating Striga resistance in backcrossed populations.
Pyramiding or building up Striga resistance in these breeding lines via MAB is important. However, further exploration of appropriate markers is needed to develop efficiently the varieties preferred by farmers. Likewise, more markers linked to various traits that meet farmersâ&#x20AC;&#x2122; preferences identified in the PRA and FPVS also need to be converted to SCARs for use in MAB. This project was able to identify germplasm lines with resistance to Striga races predominant in the Niger Republic; identify farmersâ&#x20AC;&#x2122; constraints and preferences to aid in selecting for important traits to combine with Striga resistance; and conduct with farmers the participatory field testing of the new Striga-resistant improved lines developed via the MAB method. It also confirmed the efficiency and effectiveness of MAB for Striga resistance.
Farmers selecting cowpea varieties in the field in Tchadoua, Niger.Photo by S. Muranaka, IITA.
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Cowpea and other Vigna species in Serbia Aleksandar Mikić (aleksandar.mikich@gmail.com), Mirjana Milošević, Vojislav Mihailović, Charassri Nualsri, Dušan Milošević, Mirjana Vasić, and Dušica Delić Serbia and other countries of the northern and western parts of the Balkan Peninsula have a typical temperate continental climate. The most important grain legume crop here is soybean (Glycine max (L.) Merr.) with an advanced native breeding program carried out in the Institute of Field and Vegetable Crops in Novi Sad. The most widely used pulse is the Phaseolus bean that has almost completely replaced traditional varieties, such as faba bean (Vicia faba L.) or lentil (Lens culinaris Medik.). The pea crop (Pisum sativum L.) retained its place both for human consumption and in animal feeding. Vetches (Vicia spp.) are used as both a forage and green manure crop.
origin, was included in the official Serbian cultivar list. Cowpea may be found, rather sporadically, along with various market classes of common bean (Phaseolus vulgaris L.), especially in the valley of the Morava river in central Serbia. Local people usually refer to it as pasuljica (little common bean), not really distinguishing it from various types of common bean. Like these, cowpea is used as a vegetable in diverse forms and is grown mainly in gardens.
Cowpea (Vigna unguiculata (L.) Walp.) is not completely unknown in the Balkans, with several Serbian/ Croatian words denoting this crop. Often it is called simply vigna, as the whole genus, or prava vigna (true vigna), to distinguish it from the other related species. There are also descriptive names, such as crnookica (black-eyed one) and kravlji pasulj (cow bean). Another name, mletački grašak (Venice pea) suggests that this species was most likely introduced into the Balkans from northern Italy. Cowpea was distributed in the coastal regions of Croatia, one of the countries that formed the former Yugoslavia, where the Italian cultivar “Cremonese” showed very good results when grown both as a pure stand and in mixtures with Sudan grass, sorghum, and maize. Today, cowpea has remained a rather neglected and underutilized crop in Serbian agriculture. Only one cowpea cultivar named “Domaća”, of uncertain
Evaluation of important agronomic traits in cowpea and other Vigna species. Photo by A. Mikic.
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Recently, along with the introduction of new trends such as the preference for healthy food, it is possible to buy adzuki bean (Vigna angularis (Willd.) Ohwi & H. Ohashi), mung bean (Vigna radiata (L.) R. Wilczek), and black gram (Vigna mungo (L.) Hepper), mostly of Chinese origin. These are used as pulses.
for grain were presented at the 4th World Cowpea Congress in Durban in 2005 (Table 1). The most important conclusion from this evaluation was that the short day length in some accessions was the major reason for their inability to produce seeds before the first winter frosts in October.
The genetic resources of cowpea and other Vigna species in Serbia are maintained mainly in the Institute of Field and Vegetable Crops, with its Vegetable Crops and Forage Crops Departments, as well as in the Institute of Soil Science, with a total of some 30 diverse accessions.
The next step in testing cowpea potential in the conditions of Serbia was to evaluate its forage yields. It is possible to select the lines that could be developed into proper dual-purpose cultivars, with reliable yields of both grain and forage (Table 2).
Since 2004, an evaluation of the most important agronomic traits in cowpea and other Vigna species has been initiated within the field trials in the Institute of Field and Vegetable Crops, at 45°20' N, 19°51' E and 84 m asl. As typical warm-season annual legumes, cowpea and other Vigna species were sown in late April. The preliminary results of the trial with cowpea grown
The evaluation of the cowpea accessions continues along with the evaluation of the adzuki and mung bean that has also brought promising results. Due to its multipurpose nature, cowpea could be reintroduced into the agriculture of Serbia and other southeast European regions in several ways. An improvement could be made by developing vegetable cultivars for
Table 1. Selected results of the preliminary evaluation of grain yield in cowpea accessions in Novi Sad, Serbia, during 2004. Acc. name
Country of origin
Thousand-seed weight (g)
Grain yield (kg/ha)
Harvest index
Xincharo
Portugal
225
3460
0.29
NI 147
France
14
57
0.01
NI 188
Suriname
206
2286
0.23
NI 479
DRC
152
1010
0.34
Table 2. Selected results of the preliminary evaluation of green forage and forage dry matter yields in cowpea accessions in Novi Sad, Serbia, during 2004. Acc. name
Country of origin No. days from sowing to cutting
Green forage yield (t/ha)
Forage dry matter yield (t/ha)
Xincharo
Portugal
139
45.9
12.9
NI 147
France
148
11.9
3.3
NI 188
Suriname
113
39.2
11.0
NI 479
DRC
130
11.8
3.3
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Mutual intercropping of annual legumes for forage production. Photo by A. Mikic.
both garden use, with a longer growing period and prolonged maturity, and field production, with prominent earliness and uniform maturity. As a forage crop, cowpea may play a very important role in providing farmers with fresh forage during the summer months, when the pea crop or vetches have long gone from the fields. However, breeding cowpea for forage production must provide not only good, high quality forage yields, but also reliable seed yields, enabling a newly-developed forage cowpea cultivar to survive in the market. All this emphasizes the importance of selecting the genotypes with an appropriate photoperiodical reaction.
In 2009, the trials started with mutual intercropping of annual legumes for forage production. Cowpea, adzuki, mung bean, and black gram, with poor standing ability, were deliberately mixed with soybean that acts as a supporting crop. Preliminary results showed that mixtures with cowpea may produce more than 40 t/ha of green manure with a Land Equivalent Ratio (LER) higher than 1, proving its economic reliability. The first step towards international cooperation in cowpea research involving Serbia is a project with the Prince of Songkla University, aimed at collecting cowpea landraces in Thailand and their complex evaluation in contrasting environments.
Institutional affiliation Aleksandar Mikić and Mirjana Milošević, Ministry of Agriculture, Forestry and Water Management, Belgrade, Serbia Vojislav Mihailović and Mirjana Vasić, Institute of Field and Vegetable Crops, Novi Sad, Serbia Charassri Nualsri and Dušan Milošević, Prince of Songkla University, Faculty of Natural Resources, Songkla, Thailand Dušica Delić, Institute of Soil Science, Belgrade, Serbia
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Man feeding sheep with cowpea haulms. Photo by ILRI.
Enriching livestock diets with cowpea Elaine Grings, e.grings@cgiar.org Loaded on camel-back, covering roofs, stored in tree tops, and traded in the market, cowpea haulms can be seen throughout the semi-arid tropical regions being stored, marketed, and used as livestock feed. Expanding the intensification of crop−livestock systems encourages the use of dual-purpose cowpea varieties that produce high yields of both grain and fodder. Research on yield and quality of cowpea haulms by centers belonging to the Consultative Group on International Agricultural Research is leading to improvements in livestock production and the associated incomes of crop−livestock farmers. Cowpea is an important component in mixed crop−livestock systems in the semi-arid regions of the tropics. It is being grown more and more to provide high levels of fodder for livestock in addition to producing grain for people. Since the late 1980s, cowpea
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breeding programs have worked toward producing dual-purpose varieties that emphasize the production of grain and fodder resulting in varieties that can yield over 1 t/ha of grain and 2 t/ha of fodder. Crop residues—the stalks, stems, and leaves remaining after seed harvest— make up a major component of livestock diets in mixed crop−livestock systems. Improving the nutritional quality of crop residues is thus important to enhance the productivity and profitability of these farming systems. Demand for livestock products through much of the semi-arid tropics will be likely to continue to increase along with the use of purchased feedstuffs. For this reason, sales of cowpea fodder have been expanding, providing cowpea farmers with additional opportunities for marketing their surplus crop.
Late-maturing varieties of cowpea are often used for fodder because they can take advantage of a longer growing season to amass more biomass. Where the longer growing period can make the crop susceptible to late drought, varieties may be preferred with a high fodder yield produced within a more moderate growing period. A collaborative program between IITA and the International Livestock Research Institute (ILRI), which was started in the 1980s to evaluate and develop dualpurpose varieties, has produced several that have become well accepted when tested on-farm. It is useful to know the differences in performance of livestock fed on different varieties of cowpea. Some varieties have been tested for their ability to increase the weight of small ruminants or improve the milk yield of cows. However, only a few varieties can be compared at one time in live animal trials. This makes the systematic screening of cowpea genetic resources important for advancing the development of dual-purpose varieties.
based on cereal stovers and other lowquality forages. Optimizing the amount of cowpea haulms in livestock diets was one focus of a research project sponsored by the CGIAR Systemwide Livestock Program on the use of cowpea fodder. As smallholder livestock systems evolve and become more market-oriented, the type of diets fed to livestock often changes. Legume fodders remain an important part of these changing diets. The development of cowpea varieties that feed both people and their farm animals better will give farmers new and wider choices. There is still much to be done. With significant variation existing within cowpea germplasm collections, we can continue to improve dual-purpose varieties. Modern technologies are available to allow the rapid screening of important quality traits. Techniques such as NIRS for quality analysis and marker-assisted selection for desirable traits promise to speed the future development of new varieties of dualpurpose cowpea.
Screening tools that can rapidly assess the nutritional quality of different varieties greatly aid the evaluation process. Near-infrared reflectance spectroscopy (NIRS) is one such tool, allowing the fast and inexpensive analysis of small quantities of plant biomass. This technique uses nearinfrared light to measure nutritive quality, such as the amounts of nitrogen and fiber, or the digestibility of the fodder, all of which are related directly to animal performance. The technique takes only a few minutes, replacing the hours of chemical analysis that were once needed to evaluate ground samples of fodder. Once screened, selected varieties could be tested further to verify their performance potential. The greater nutritional quality of legume residues allows them to be used as a supplement to livestock diets
Woman farmer tending to her goat. Photo by ILRI.
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All about the bag, not the bug Dieudonne Baributsa, dbaribut@purdue.edu Farmers throughout West and Central Africa call it the “magic bag”—the triple layer bag developed by Purdue University and partners to control the cowpea bruchid Callosobruchus maculatus. The bag does not use any of the chemicals that are so often misused, or overused, causing the health hazard commonly referred to as “killer bean” in Nigeria. The technology is being widely adopted because it is simple, easy to use, effective, and profitable to farmers and other users. Professor Larry Murdock led a team composed of the Purdue University faculty, students, and other partners to initiate the development of this technology in the late 1980s with funds from the Bean/Cowpea Collaborative Research Support Program (CRSP). In 2007, with funding from the Bill & Melinda Gates Foundation under the Purdue Improved Cowpea Storage (PICS) project (http://www.ag.purdue. edu/ipia/pics), the technology was refined and is being disseminated in 10 countries in West and Central Africa:
Nigeria, Niger, Burkina Faso, Mali, Togo, Bénin, Ghana, Cameroon, Chad, and Senegal. The PICS project has two thrusts: outreach activities that are expected to reach around 28,000 villages, and supply chain development. The project has just entered its fourth year. Outreach activities have been implemented in collaboration with IITA, World Vision International, National Institute for Agricultural Research of Niger (INRAN), National Institute for Agricultural and Environmental Research (INERA) of Burkina Faso, Institute of Agricultural Research for Development (IRAD) of Cameroon, national extension systems in various countries, farmers’ associations, and NGOs. To date, the technology has reached more than 23,000 villages in Nigeria, Niger, Mali, Burkina Faso, Togo, and Bénin. The project has recently launched activities in the four remaining countries (Senegal, Ghana, Cameroon, and Chad) with the completion of the training for field technicians.
Segou, Mali: Women are observing their cowpea stored in PICS bags (for more than 5 months) after the openthe-bag event. Photo from D. Baributsa, PICS.
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The PICS project is also developing a supply chain system for the triple layer sacks in West and Central Africa. The development of this system is providing business opportunities for manufacturers of sacks, distributors, and vendors. The PICS project has worked with five manufacturers of plastics in five West African countries to produce over 1.25 million bags. In addition, Purdue has worked with local entrepreneurs to sell the storage technology through their distribution networks so that it is easily available to farmers. More than 100,000 PICS bags have been used in village demonstrations. The technology has proved to be effective. Cowpea in all of the PICS bags were as good during the openthe-bag events (in April and May) as they were at harvest time (October and November), except for the occasional bag that had been damaged by rodents or accidentally pierced. Communication has been a major part of the PICS efforts. Radio, print media, TV, and cell phone videos have been used to build awareness about the triple layer technology. Messages in local languages have been effective in communicating the technology to farmers and other users. Research by Purdue University has determined that the radio is key and effective in reinforcing the PICS technology message in rural villages. Print media, such as posters and flyers on â&#x20AC;&#x153;fiche techniques,â&#x20AC;? are also being disseminated in local languages. TV spots on the technology have been broadcast in some areas, but few in rural West and Central Africa have access to TV. The PICS project is taking advantage of the use of cell phones with Bluetooth, a wireless communications technology that facilitates data transmission over short distances, in rural communities to disseminate video clips describing the use of the PICS technology.
Lankoue, Burkina Faso: Young men carrying cowpea in triple layer bags to their village after a PICS event. Photo from D. Baributsa, PICS.
Hermetic sealing is difficult to describe in words on the radio or in print, but many people immediately understand it if they see it demonstrated. To facilitate visual learning on the use of hermetic storage, the PICS project developed cell phone videos in Hausa (Niger and Nigeria), French (Niger and Cameroon), Fulfulde (Cameroon), and English (Nigeria). An assessment of the PICS cell phone video dissemination showed its potential as an effective means of conveying extension messages to farmers. Womenâ&#x20AC;&#x2122;s participation has also been at the forefront of PICS activities. A goal was set of 30% participation and this has significantly increased the number of women involved in both field staff training and village activities. Several strategies have been used to reach this goal, including recruiting female field technicians to conduct training for women in areas where mixed gender gatherings are not allowed, competitions for women about cowpea, and other approaches. The PICS project is currently seeking ways to expand the use of the triple layer bag to store crops other than cowpea.
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Genetic resources:
To conserve or not to conserve?
Crop improvement through breeding and biotechnology is one way of tackling the challenges of feeding the world. Conservation of genetic resources is an important component of crop improvement, providing a pool of materials for the researchers to draw from. IITA’s Genetic Resources Center (GRC) created in 1975, maintains over 28,000 accessions of six main staple crop collections that are available to food and agriculture researchers worldwide working on crop improvement. They are cowpea or “black-eyed pea” (Vigna unguiculata L.), maize (Zea mays L.), soybean (Glycine max (L.) Merr.), cassava (Manihot esculenta Crantz), yam (Dioscorea spp.), and banana (Musa spp.).
research to institutions in sub-Saharan Africa, Asia, USA, and South America. This has contributed to the development of new cultivars or varieties currently adopted by rural farmers in the regions. The effectiveness of the distribution system from the genebank, the use of the distributed germplasm, and conservation costs were assessed in a study conducted by Victor Manyong, Dominique Dumet, and A.T. Ogundapo from IITA and D. Horna from the International Food Policy Research Institute. Likewise, the impact of the conservation of germplasm of cowpea and wild relatives was examined to justify the conservation efforts.
Over 50% of the collection is made of cowpea collected from 89 countries, mainly in Africa, and other Vigna spp. It is also the most shared, with 54 of all the germplasm materials being distributed.
Methodology Questionnaires were e-mailed to partners who had collected germplasm from GRC between 1975 and 2009 to determine the ease of accessing material and their use. To estimate the cost of conserving a unit of the two crops, the Decision Support Tool (DST) developed by IFPRI was used.
Since 1985, IITA has distributed germplasm of cowpea and its wild Vigna relatives for genetic improvement
Only about 13% of the beneficiaries responded but they accounted for about 84% of the accessions distributed to
5 °C
In vitro
Ex situ conservation, IITA genebank: medium-term storage. Photos by IITA.
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beneficiaries in West Africa, Asia, East Africa, Europe, and North America. No responses were received from beneficiaries in Australia, the Caribbean, Central Africa, the Middle East, North Africa, South Africa, and South America. This may partly have been due to lack of updated contact details in the genebankâ&#x20AC;&#x2122;s electronic database. This needs to be improved for future feedback surveys. Use of cowpea and wild Vigna germplasm The study findings show that most of the distributed cowpea and wild Vigna accessions were used for breeding followed by activities in agronomy and biotechnology research. However, in many cases, they had multiple uses, such as breeding, biotechnology, and agronomy. Between 2001 and 2005, about 76% of the accessions were used for various agricultural research activities and were found adaptable to different agroecological zones, from forest to the savanna in the tropics and subtropics. Derived, Sudan, and Sahel savannas were recognized as the adaptable agroecological zones for the cultivation of cowpea and wild Vigna. The majority of the users of the germplasm found it easy (32%) to very easy (68%) to get the material from -20 °C
Ex situ conservation: field genebank. Photo by IITA.
the genebank. Only a few experienced difficulties. These included the inability of the genebank to supply the required quantities (3% of accessions), poor collaboration with NARS and universities (3%), long bureaucratic procedures to acquire germplasm (2%), and improper documentation of the passport database of accessions (1%). Desired traits High yield and pest resistance were the two traits desired by the majority of agricultural researchers who made requests, irrespective of their specialization. Other desired traits included compatibility to cross with other accessions, seed color and size, nutritive value, palatability and attractiveness, drought tolerance, nematode resistance, early flowering, and storability. -196 °C
Ex situ conservation, IITA genebank: long-term storage. Photos by IITA.
25
IITA maintains more than 15,000 accessions of cowpea in its genebank. Photo by IITA.
Moreover, many were satisfied with the accessions they received. Findings show that 68% of the accessions received by agronomists met their desired traits, 76% for food technologists, but only 3% for breeders where the main issue was the low level of resistance to pests and diseases. However, the breeders recorded 100% satisfaction in the exploitation of accessions for seed color, seed size (good), and compatibility with crossing. Likewise, 95% satisfaction was achieved on high seed yield and 74% on the combination of high yield and pest resistance by some of the breeders. Cost of conservation The structure cost of the genebank in the DST has four categories: capital, quasi-fixed, variable labor input, and variable nonlabor input. Capital inputs include infrastructure, such as germplasm storage and genebank facilities, and equipment for field operations and offices. Using 2008 as a reference year, US$358,143 and $28,217 was spent annually on the conservation and
26
management of cowpea and wild Vigna. The capital cost took the major share of the costs, followed by quasi-fixed costs for scientific staff, nontechnical labor, and nonlabor supplies and consumables. Each accession cost about $72 for cowpea and only about half of that for wild Vigna. A large share of the expenditure, $28,537, went into the regeneration of 2,228 accessions of cowpea, at an average cost of approximately $12.81 per accession. Cowpea germplasm is regenerated in the screenhouse to produce high quality germplasm, with considerations of purity and sanitation, hence the relatively high cost per accession. Seed health testing ($13.94/accession) and distribution ($22.63/accession) were the other high costs. One way to reduce these costs is by increasing the number of accessions, thus lowering the unit cost. Also, upgrading and expanding the current infrastructure to improve the efficiency of the genebank were recommended.
Harvesting cowpea. Photo by IITA.
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Cowpea trivia Trivia 1. Cowpeas are thought to get their name from when they were a key livestock feed in the USA. 2. The cowpea is 25% protein. 3. 52% of the cowpeas produced in Africa are used for food. 13% are used for animal feed, 10% are used for their seeds, 9% goes to other uses and 16% are wasted. 4. In the Southern United States eating black-eyed peas on New Year’s Day is considered good luck because they symbolize money. 5. In Yoruba cowpeas are called ewa or ere. In Hausa they are known as wanke. And across the French-speaking regions of West Africa they are called niebe.
Recipes Akara Ingredients ½ pound dried black-eyed peas/ cowpeas 2 onions 1 red pepper Salt Ground white pepper Olive oil 2 ripe tomatoes 1 green pepper ¼ cup chopped parsley leaves Directions 1. Soak peas for 24 hours or overnight in water. Drain. Peel the outside skin from the peas.
4. To serve, make a quick dipping sauce by pulsing 2 de-seeded tomatoes, 1 onion, 1 green pepper, and some parsley in food processor. Add olive oil and season with salt and pepper to make a chunky salsa.
Lobia (Black-Eyed Beans Curry) Ingredients
2 cups lobia (black-eyed beans) 1 ½ tsp Salt to taste 1 ½ tsp ground coriander ¾ tsp ground cumin ½ tsp ground turmeric 2 tbsp oil 1 small onion, chopped 2 large cloves garlic, chopped 1 (¾-inch piece) ginger root, peeled and chopped ½ tsp Scant cumin seeds 1 medium tomato, chopped
2. In a processor, coarsely chop the onion and red pepper. Add soaked peas and puree to a paste. Transfer to a bowl and using a whisk, whisk the mixture adding salt, white pepper, and just a little liquid--not too much as the mixture needs to retain its Directions shape for frying. 1. In pot soak beans overnight in water to 3. Using an ice cream scoop, form into balls cover generously. Next day, drain beans, about the size of a ping-pong ball. Drop into cover with fresh water and bring to boil. a pot of hot olive oil, heated to around 180 ˚C. Fry until golden brown. Remove and 2. Add salt, coriander, cumin, and turmeric. drain on a paper towel-lined plate. Season Simmer until beans are just tender, about 30 again with salt and pepper. to 45 minutes.
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3. Heat oil in deep saucepan. Add onion, garlic, ginger, and cumin. 4. Fry 10 minutes and add tomato. Cook another 5 minutes and add lobia (black eyed beans) and cooking liquid. Continue to simmer, uncovered, until lobia are soft but not completely dissolved. Mixture should be soupy.
Lobia Tomato Masala Curry 1 cup cooked black eyed beans 1 onion, chopped ¼ tsp cumin seeds ¼ tsp fenugreek seeds Salt Oil Chopped coriander leaves Grind: 2 tomatoes, chopped ½ tsp peppercorns 1 tsp coriander seeds 1 tsp fennel seeds 2 tsp poppy seeds 1 tsp cumin seeds 5 garlic pods 3 dry red chillies Directions
Red-Red (Cowpea stew, also known as Black-Eyed Pea Stew)
Ingredients 240 g black-eyed peas (cooked) 1 medium onion, sliced 2 large tomatoes, finely chopped ½ tbsp chilli powder 2 tbsp red palm oil (or 2 tbsp groundnut oil + ½ tsp paprika) salt and black pepper to taste Directions 1. Soak the black-eyed peas in water for at least an hour or overnight. After soaking, rub them together between your hands to remove the skins. Rinse to wash away the skins and any other debris. Drain. 2. Mash the black-eyed peas and set aside. 3. Heat the oil in a pan and cook the onion and tomatoes until soft. Add all the remaining ingredients (including the peas) and simmer for 10 minutes. 4. While peas and sauce is simmering, prepare fried plantains. Serve peas and plantains side by side on a plate.
Hoppin' John
1. Dry fry the peppercorns, coriander seeds, Ingredients poppy seeds, cumin seeds, and fennel 1 ½ cups dry black-eyed peas seeds and simmer for a while. 1 pound ham hocks 2. Add the fried seeds and tomatoes, garlic 1 onion, chopped pods with 1 cup water and grind them ½ teaspoon crushed red pepper flakes coarsely. Then add ¼ cup of the cooked salt and pepper to taste black-eyed beans to the spices and grind 4 cups water everything as a fine paste. 1 ½ cups long-grain white rice 1 cup shredded smoked Cheddar cheese 3. Heat oil in a pan, add the cumin seeds n fenugreek seeds and let them splutter. Add Directions the chopped onion and stir them until they 1. In a large pan place the peas, ham hock, turn translucent. Next, add the grounded onion, red pepper, salt, and pepper. Cover paste and simmer for a while. The mixture with water and bring to a boil. Reduce heat will stick very easily to the bottom of the to medium-low and cook for 1 ½ hours. pan, so keep on stirring, adding enough water and salt to the gravy. 2. Remove ham hock and cut meat into pieces. Return meat to pot. Stir in the rice, 4. Once the oil separates from the gravy, cover and cook until rice is tender, about 20 add the rest of the black-eyed beans and to 25 minutes. Season to taste with salt and cook the mixture for a few more minutes. pepper. Sprinkle shredded cheese over top, Add the chopped coriander leaves, and if desired. Serve. then turn off the stove.
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BEST Practice
Joining hands to fight the legume pod borer Manuele Tamò, m.tamo@cgiar.org A new collaborative project has been launched to develop novel approaches against an old problem affecting cultivated legumesâ&#x20AC;&#x201D;the pod borer Maruca vitrata. This is one of the major pests of cowpea in West Africa, where, if left uncontrolled, it can lead to 80% yield losses. Under this new project, funded by the German Federal Ministry for Economic Cooperation (BMZ), IITA and partners, the World Vegetable Center (AVRDC), and the International Center for Insect Physiology and Ecology (icipe), will test a range of new natural enemies against the legume pod borer. In close collaboration with national agricultural research systems (NARS) and scientists and colleagues in the Plant Protection and Quarantine Services, the project will choose the most promising natural enemies adapted to West and East African conditions. One of the major outcomes of this project will be to quantify the impact of selected biocontrol agents on the population ecology of the pod borer and on cowpea yield in the field. At the same time, detailed molecular analysis of pod borer populations from different parts of the tropics, Africa, South America, and Asia, in collaboration with the BMZ project and a Dry Grain Pulses Collaborative Research Support Program (DGP-CRSP) project with the University
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A typical symptom of Maruca vitrata larva affected by the entomopathogenic virus MaviMNPV (moribund larva hanging down from plant). Photo by S. Srinivasan, AVRDC.
of Illinois, will permit the identification of scoreable polymorphisms for determining the genetic similarity and differences between pod borer populations at distant locations. This will enable project staff to answer questions in relation to differential responses to synthetic pheromones, the diversity of biocontrol agents, and the development of an insect resistance management plan in preparation for the deployment of Bacillus thuringiensis (bt) cowpea in the region.
Prior to this new project, AVRDC and IITA have already collaborated, both formally and informally, on research on pod borer control. Biodiversity studies carried out at AVRDC in Taiwan had identified the exotic parasitoid Apanteles taragamae as the most promising candidate. This was subsequently introduced into the laboratories of IITA Bénin station. After a series of prerelease tests, experimental inoculative releases of A. taragamae were carried out between February and June 2007 in Bénin, Ghana, and Nigeria. The sites were patches of wild vegetation including plants known to host the pod borer, such as the legume trees Lonchocarpus sericeus, Pterocarpus santalinoides, and the shrubs Lonchocarpus cyanescens and Tephrosia spp. As early as 6 months after the first releases IITA started a series of surveys to monitor the establishment of the parasitoid in the neighborhood of the releases. The monitoring continued until 2009, during which time we were not able to recover the parasitoid. However, we found indirect evidence of establishment in the environment (see below). We ruled out the theory that
interspecific competition with indigenous parasitoids exploiting M. vitrata larvae of the same age and on the same host plant was the cause for this lack of evidence. We had conducted, just before the releases, quite elaborate competition studies which did not reveal any problems. Also, in its area of origin in Taiwan, A. taragamae coexists with similar parasitoid species found in Bénin, e.g., Phanerotoma sp. and Dolichogenidaea sp. In Taiwan, however, A. taragamae is found prevalently on the cover crop Sesbania cannabina. This has been difficult to grow in West Africa because of foliage beetles (particularly Mesoplatys sp.) that completely defoliate the plant. We also intensified our studies on African indigenous species of Sesbania which suffer less beetle damage. So far, there have been no signs of direct establishment, although screenhouse experiments have confirmed the suitability of Sesbania spp. both as a feeding substrate for the pod borers and as a host for foraging parasitoids. More recently, with funds from DGPCRSP, we have developed a new release
Experimental release of the parasitoid Apanteles taragamae using caged Sesbania cannabina. Photo by M. Tamò, IITA.
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system using caged S. cannabina, infested artificially with eggs of M. vitrata, and subsequently inoculated with adult A. taragamae. Preliminary results indicate that such a cage can produce up to 300 cocoons of the parasitoid. At this stage, the cage can be removed and the parasitoids can emerge from the cocoons and disperse in the surrounding natural habitat. This deployment system is currently under testing in Bénin.
In Bénin, we did not carry out any open field experiments, so we were puzzled to discover a few pod borer larvae collected in the Mono region, close to release sites of the parasitoids, with apparent signs of the virus (Note: MaviMNPV had never been found in Bénin nor anywhere else in West Africa prior to the introduction in 2007, as confirmed by surveys of Dr A. Cherry in collaboration with the Natural Resources Institute).
Another important beneficial organism which was identified by AVRDC in Taiwan is the Maruca vitrata MultiNucleopolyhedrosis Virus (MaviMNPV). This was imported to IITA-Bénin for further assessment. Again, after a series of laboratory tests which confirmed the results obtained in Taiwan and ascertained the specificity of MaviMNPV to the target host, IITA proceeded to test the virus in seminatural conditions. For this, we used field cages with artificial infestations of M. vitrata larvae. These experiments were also replicated in the screenhouse in Kano, Nigeria. Both tests indicated a very high mortality of pod borer larvae (>95%) using standard concentrations comparable to those found in commercial formulations of entomopathogenic viruses (e.g., against the cotton bollworm Helicoverpa armigera).
Based on this discovery, and also aided by literature support, we attempted to verify the hypothesis that the parasitoid A. taragamae could have transmitted the virus MaviMNPV to pod borer larvae. We used three different infection methods (ovipositor only, whole body without ovipositor, and indirectly through artificial diet) to test the hypothesis. Results confirmed that the parasitoid was able to transmit the virus to the larvae through any of the infection methods. This discovery is quite significant: the parasitoid may be able to spread the virus in the environment without any further intervention.
Adult female of Maruca vitrata. Photo by G. Goergen, IITA.
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This is also indirect evidence that A. taragamae is present in the environment, maybe at low levels, that cannot be detected by current sampling methods, or on secondary host plants for M. vitrata whose identity is still unknown. Further studies indicated that A. taragamae females can pass on the virus up to the third generation. At present, we are looking for low-cost and efficient ways of producing the parasitoid and the virus so that the technology can be implemented by NARS colleagues and cottage industries at the community level, with financial support from DGP-CRSP. Also, training and demonstration videos of the major cowpea pests, their natural enemies, and detailed rearing methodologies are being prepared.
Improved cowpea varieties for Nigeria’s savanna region Nigeria has released two new cowpea varieties to raise production and improve farmers’ incomes.
is certainty of rains up till the end of October, IT89KD-288 can be planted in September.
The varieties—IT89KD-288 and IT89KD-391—were developed by scientists working at IITA, Ibadan, in collaboration with the Institute for Agricultural Research of the Ahmadu Bello University, Zaria; University of Maiduguri, Borno; and the Agricultural Development Programs of Borno, Kaduna, Kano, and Katsina States.
IT89KD-391 (now SAMPEA-12) is also a dual-purpose cowpea variety but it has medium-to-large brown seeds with a rough seed coat. These are preferred seed characteristics for commercial production in northeast Nigeria.
Both varieties have proven to be superior over the current improved lines being cultivated. They could be used to overcome the challenges faced by cowpea farmers in the country. For instance, IT89KD-288 (now SAMPEA-11) is a dual-purpose cowpea variety with large white seeds and a rough seed coat. It has combined resistance to major diseases including septoria leaf spot, scab, and bacterial blight, as well as to nematodes, and tolerance for Nigeria’s strain of Striga gesnerioides (a parasitic weed that severely lowers yield). “It also has a yield advantage of at least 80% over the local varieties,” said Alpha Kamara, IITA Agronomist, who is leading efforts to rapidly disseminate the varieties to farmers. The nematode-resistant variety is an equally good candidate for sowing with cereals or as a relay crop with maize in the moist and dry savanna zones, and for high grain production in the dry season. Scientists recommend that the variety be planted in mid-July in the Sudan savanna, early to mid-August in the northern Guinea savanna, and by the end of August in the southern Guinea savanna. However, if there
“IT89KD-391 is a welcome improvement over SAMPEA 7, Ife brown, IT90K-76, and IT90K-82-2 which are the main improved brown-seeded varieties available. It has been tested extensively in this area and is well accepted by the farmers,” said Hakeem Ajeigbe, IITA Extension/Dissemination Specialist. “The variety performs well as a sole crop and an intercrop. It could also be planted as a relay crop with maize in the Guinea savannas,” he added. Several on-station and on-farm trials have shown that IT89KD-391 (SAMPEA 12) produces double the yields of local cultivars. In 2008, Nigeria released a Strigaresistant improved cowpea variety (IT97K-499-35). “The demand for these improved varieties is high because of their superior yields and their acceptability by consumers,” Kamara said.
Women farmers in Kano, Nigeria. Photo by IITA.
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tool box
Conserving cowpea using GIS tools
Diversity of cowpea seeds. Photo by C. Ono-Raphael, IITA.
The germplasm collections in genebanks are an invaluable resource for the future. The conservation of this biodiversity is tied to agricultural production and represents a safety net for the food security of future generations. In addition to the conservation, multiplication, regeneration, and characterization of these collections, another central function of a genebank is the expansion of germplasm collections to cover as much agrobiodiversity as possible.
IITA works on cowpea improvement and holds the largest cowpea germplasm collection in the world (15,115 accessions); 10,814 (71.5%) of these were collected in Africa or acquired from African national programs.
The worldwide area cultivated with cowpea in 2008 was estimated to be 11.8 million ha with an annual production of 5.4 million t of dried grains (FAOSTAT 2010).
High protein food legume The cowpea is a very important, widely adapted, and versatile grain legume of high nutritional value. It is mainly produced and consumed in Africa where it provides a major low-cost dietary protein for millions of smallholder farmers and consumers who cannot afford high protein foods, such as fish and meat. Food legumes, particularly cowpea, have high protein contents. Cowpea contains 24% protein, 62% soluble carbohydrates, and small amounts of other nutrients.
Production in Africa represents about 91% of the global production. West Africa, with 10.7 million ha, accounts for most of Africa’s production, with Nigeria and Niger being the leading cowpea growing countries (FAOSTAT 2008). The area planted with cowpea is substantial in Senegal, Mauritania, Mali, Burkina Faso, Côte d’Ivoire, Ghana, Bénin, Togo, Chad, Cameroon, Central African Republic, Congo, Uganda, Tanzania, Sudan, Ethiopia, Kenya, Angola, Somalia, Zambia, Mozambique, Zimbabwe, Botswana, Namibia, South Africa, and Madagascar (NRC 2006).
It is a very low-input crop, traditionally grown in intercropping systems. Cowpea contributes to soil fertility through nitrogen fixation and is also cultivated to prevent soil erosion.
Cowpea diversity At IITA, cowpea is maintained in two storage conditions, medium (5°C) and long-term (-20°C) at an optimal water content of 7−8% fresh weight basis.
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The viability of most accessions stored at –20°C for 25 years remains as high as 90%. To avoid losses of genetic diversity and to guide future sampling, researcher Anne Rysavy of the University of Hohenheim (now with the University of Tuebingen), GIS Specialist Kai Sonder (now with CIMMYT), and the head of IITA’s Genetic Resources Center, Dominique Dumet, assessed the geographic coverage of the current collection to get an overview of the crop’s conservation status. The study identified areas in Africa where the probability of finding more and diverse Vigna unguiculata accessions is highest and where further collection should be done. GIS tools Gap analysis is an evaluation technique applied to provide wide geographic information on the status of different species and their habitats using satellite data and different computer tools and by digital map overlays in a geographic information system (GIS). Gaps refer to geographical areas that are underrepresented in the collection and where cowpea is expected to occur based on agrometeorological and other factors. GIS can be a powerful tool for analyzing spatial distribution of a species. Combined with biophysical information from germplasm collections, it can help in conducting surveys and prioritizing future sampling areas. Areas that have not yet been sampled can be targeted for collecting missions so that the material can be conserved ex situ or using in situ conservation strategies. Specifically, the study analyzed, corrected, and georeferenced the available passport data for cowpea. It also applied different GIS tools to identify gaps in previous collection areas, and predicted areas where new diversity is likely to be collected and/ or areas where diversity erosion risk is
highest, e.g., from climate change, civil war, deforestation, etc. This study used spatial analysis tools and software applications, such as FloraMapTM, HomologueTM, ArcGISTM, and DIVA-GIS, including the predictive models EcoCrop, BIOCLIM, and DOMAIN to perform the gap analysis on the existing cowpea germplasm collection at IITA and identify potential areas for future conservation activities. First the country coverage of georeferenced cowpea accessions was determined. Then, ecogeographical site descriptors (temperature, precipitation, length of growing period, and altitude) were extracted to determine areas with environmental conditions favorable to cowpea. Based on this, regions with similar environmental conditions were identified using GIS techniques. Gaps in cowpea collection Study results provide an overview of the actual distribution, agroclimatic preferences, and potential distribution of cowpea. The geographical scope of the study focused on sub-Saharan Africa. Results indicated that cowpea can be found approximately between 15°N and 20°S, and over a large range of climates—temperature as well as precipitation. However, it occurs most likely in subtropical to tropical conditions characterized by warm temperatures (annual average >20°C) and relatively high annual precipitation (>250 mm). The distribution of the total number of cowpea accessions held in the IITA genebank is very diverse with a certain concentration in West Africa (see map). Nigeria and Niger account for nearly 50% of all accessions. The origins of the remaining 50% are unequally distributed across the continent. Several countries such as Burundi, Equatorial-Guinea, Eritrea, GuineaBissau, Namibia, and Rwanda are not represented.
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useful approaches to conserving the genetic diversity of crop species.
Distribution of the 10,814 cowpea accessions.
Depending on the country, the total number of accessions collected within Africa ranged between one (Algeria and Angola) and 3,813 (Nigeria). Nigeria ranked first with 35.3% and Niger second with 11.6% (1,249 accessions). Cameroon, Botswana, and Zambia accounted for 15% of the total number of accessions, each contributing 5%. Tanzania, Malawi, BĂŠnin, Egypt, Ghana, Mali, Burkina Faso, and Senegal accounted for 24.4%. All the methodologies used identified areas where, according to agroecological similarities, the probability is high of finding more cowpea accessions and no collections have been carried out yet, or very few accessions have been collected. They proved to be
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Based on the predictive models, the following countries were identified as the priority for the acquisition of new germplasm: Angola, Burundi, GuineaBissau, Eritrea, Equatorial-Guinea, Namibia and Rwanda, especially since no collections have yet been made in these countries. In addition, further sampling is recommended in countries with small numbers of georeferenced accessions, such as Botswana, Congo, DRC, Gambia, Lesotho, Liberia, Madagascar, Sierra Leone, Sudan, Swaziland, and Uganda. Germplasm acquisition will be done through the duplication of existing national collections at IITA with the support of the Global Crop Diversity Trust (GCDT), and specific collecting missions to capture missing diversity. The GCDT has commissioned IITA to lead the development of a global conservation strategy for the genetic resources of cowpea and its wild relatives with an emphasis on Africa. References http://faostat.fao.org/site/567/default. aspx#ancor NRC. 2006. Cowpea. pp. 104-117 in Lost Crops of Africa: Volume II: Vegetables. The National Academic Press. National Research Council, Washington, D.C., USA. http://books.nap.edu/ openbook.php?isbn=0309103339&page=104, visited on 11.02.2009.
Is mechanization the solution to cowpeaâ&#x20AC;&#x2122;s woes? The cowpea is one of the most important grain legumes in Africa. Cowpea is both economically and nutritiously significant. Its ability to fix nitrogen efficiently and grow in a wide range of conditions means that the cowpea is also a suitable companion for a wide range of other food and fiber crops.
When fully mature the plants are ready to be harvested. This involves cutting the dry pods before they are attacked by birds or rodents. After this the pods must be opened to release the grains. This is done in two stages: first, the pods are beaten to open them and then they are scooped up and fanned out to separate the grains from the shells in a
Nigeria is the worldâ&#x20AC;&#x2122;s largest producer of the crop, growing 45% of the global yield. However, this total amount has dropped considerably in the past 30 years, from 61% in 1981 to 45% in 2004. With cowpea playing such a key role in the agriculture and food supply of Nigeria, production and processing practices need to be improved, emphasized Thierno Diallo of IITAâ&#x20AC;&#x2122;s Postharvest Utilization Unit. The production and processing begins before the seeds have even been planted. Land clearance involves cutting down trees, pulling up stumps, leveling the land, and extracting roots and stones. Of all the agricultural operations, land clearance is the most difficult and costly. After this the soil must be properly prepared to create good conditions for the seeds to germinate and grow. This starts with the time- and energyconsuming preparation of the seed bed and includes planting and fertilizing. The plant must then be maintained for its life span. This means preventing weeds, pests, and organisms that cause diseases such as bacteria, fungi, and viruses, from severely affecting the crop, as well as keeping the cowpea irrigated if so required.
Beating cowpea pods to open them. Photo by IITA.
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process called threshing. The grains are collected and dried to increase quality and shelf life, then stored. All of these operations are traditionally done by hand or with the help of animals and are thus associated with drudgery. â&#x20AC;&#x153;The mechanization of existing tools and the promotion of efficient farm management techniques could be the way to increase Nigerian cowpea production once again,â&#x20AC;? Diallo said. Diallo had been involed in designing some processing machines now in use by small industries in Nigeria and other sub-Saharan African countries. The advantages of mechanization have already been demonstrated with threshing. Traditionally, sticks were
used to beat the grains out of the pods but they sometimes broke the seeds, rendering them useless. In the 1990s, IITA introduced a tool called the Failsafe Flail, which prevented most of the damage to seeds. The motorized multicrop thresher further improved the process as it could do the job of several workers with flails, taking away much of the drudgery. These two devices increased the productivity of threshing. The recent introduction of a fanning system to the multicrop thresher has made it significantly better still. Drying is another area where successful mechanization has been implemented. Farmers used to spread the cowpea grains on the ground to dry under the sun. The introduction of drying platforms has not only made the process more hygienic but also more flexible as it does not depend on the sun any longer. Dryers of various designs and capacities are available, from small drying shelves to medium-capacity cabinet dryers and high-capacity rotary dryers. The larger dryers use fuels such as charcoal, wood, or diesel as the source of heat. Some are equipped with a milling facility to produce flour. By upgrading to machines such as these a farmer could not only get through the various stages of production faster but also run systems such as irrigation, uninterrupted. This in turn would cut costs and improve overall yields as well as boosting confidence and encouraging more people to grow cowpea. Furthermore, the high cost of purchasing or renting a machine would be offset by the fact that one machine is now capable of completing many different tasks.
Fabricating small machines for processing at IITA. Photo by IITA.
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Thus, when it comes to producing and processing cowpea, a move to mechanization is essential to fulfill the demand for the crop in Africa and worldwide, according to Diallo. Email: tchernodiallo@yahoo.co.uk
How to fast-track cowpea breeding IITA and partners in the Netherlands and the United States are developing genomic tools that will facilitate the development of improved cowpea varieties with traits such as drought tolerance. An IITA-Lukas Brader Postgraduate Fellow, Eugene Agbicodo, who carried out the genetic analysis of drought tolerance in cowpea and subsequently constructed a linkage map of the crop, identified portions on the cowpea genome where genes that have effects on drought tolerance and resistance to bacterial blight could be located. His findings, a landmark in markerassisted selection in cowpea improvement, will help shorten the plant breeding process. Similar work has been reported by researchers at the University of California, Riverside, and researchers at the two institutions are comparing notes on the outcomes of their research to see areas of agreement and possible collaboration, according to Christian Fatokun, Cowpea Breeder, who supervised Agbicodo's genomic mapping work at IITA.
Growing cowpea plants in a screenhouse to select for desirable traits. Photo by IITA.
â&#x20AC;&#x153;If both parties are able to find areas of agreement or concurrence, such areas of the genome would be of immense benefit when marker-assisted selection is applied in cowpea breeding. So what will normally take about 10 years to accomplish could be done in three years or even less,â&#x20AC;? he said.
Agbicodo phenotyped and genotyped a set of cowpea recombinant inbred lines generated at IITA in Ibadan. Phenotyping was carried out in Ibadan and Kano, Nigeria, while the genotyping was carried out at the University of Wageningen, The Netherlands.
With about 70% of world cowpea grown in the savanna region of Africa, the protein-rich legume provides not only incomes but also improves the health of its consumers. However, cowpea faces several production constraints, among which are diseases, insect pests, parasitic weeds such as Striga, and
drought which is becoming increasingly important in the cowpea-producing zones of sub-Saharan Africa.
Consequently, he constructed a cowpea genetic linkage map using the data obtained from genotyping and phenotyping. The linkage map showed molecular markers that defined quantitative trait loci (QTLs) with effects on drought tolerance and resistance to bacterial blight among others.
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who’s who Victor Manyong:
Strengthen socioscience capacity Victor Manyong, IITA’s director for eastern and central Africa, talks about his 17-year experience with the institute as an agricultural economist and his vision for the institute’s socioscience research. Can you give us a brief outline of your career at IITA? I joined IITA in 1992 as a postdoc fellow based at Ibadan, Nigeria. I was recruited to head a project covering 11 countries in West and Central Africa on the GIS-based macro-characterization of agricultural systems. It was a challenging 2-year research but I had a 1-year extension during which the institute’s agricultural economist left. I applied and was offered the position. Then, I became a scientist and was first posted to the moist savanna project within the Resource and Crop Management Division. As CG centers moved to a project-based approach, I was asked to lead and coordinate the project on social science research. When the DG, Hartmann, came on board, he introduced the Research for Development Council (RDC) to help him in strategic issues. I became a member of the first interim council. A year later, I was elected to serve as a council member, so I had to step down as a coordinator of social science research. After serving a 2-year term, I left RDC and became an ordinary agricultural Email: v.manyong@cgiar.org
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economist until 2005 when I was relocated to Tanzania. Here, I occupied the new position of agricultural economist for East and Southern Africa. I was also appointed the Officer in Charge of the station in 2006. What challenges did you encounter in your move from West to East Africa? It was a challenge to establish myself in a new environment, to establish a new research agenda for the institute, define my research priorities that fit in with the institute’s priorities, and to fit in with the existing team. It also was a challenge to build and strengthen a new network of partners. What can you say about the status of social science research at IITA? IITA is a commodity and natural resources management center in the CG system. Hence, social science is embedded in its research agenda. The strength of social science research at IITA is that we are working with the biophysical scientists, such as breeders, plant pathologists, and so on to create a very strong multidisciplinary team
where members benefit from one another. One problem is that we cannot have all the disciplines of social science research we need because of resource limitation. IITA’s social science has been dominated by agricultural economics while areas such as anthropology, rural sociology, political economy, and market economy have not been well addressed. However, the institute is making efforts to remedy the situation. Currently we are recruiting a market economist. We also aim to have an anthropologist. What does the agricultural economist at IITA do? We work with other scientists in designing new technologies by looking at their economic profitability and social acceptability. A technology may be good but if it is not profitable or if it is rejected by the intended users, then it will not work. We contribute to studies related to the institute’s priority setting. The agricultural economists also monitor the adoption of improved technologies, measure the benefit to the end users, determine the difference the technologies make, influence policies, and are involved in the capacity building of young professionals. Currently you are a director for R4D. What does this entail? I am a member of the R4D directorate handling the eastern and central African region covering about 11 countries. I oversee our stations in Cameroon, DRC, Kenya, Uganda, and Tanzania. As a member of the R4D Directorate, I work under the DDG-R4D to provide leadership on all R4D-related issues at IITA. What challenges have you encountered in the transition from a scientist to an administrator? Before I became the director, I was the OIC in Tanzania and a scientist. After the appointment, I now have to handle
three functions: that of a scientist, OIC, and director. There obviously is the additional workload. I therefore needed to get organized to manage all the tasks. I am also now managing more human resources, looking at relationships with government and other officials, and am the institute’s representative to the public. I needed managerial skills and to cope, I put in a lot of extra time. Currently my tasks are lighter because my duties have been reduced to those of the director and the country representative for Tanzania. What are some of the highlights of your stay at IITA? I have many but one of them was in 2005 when I published my first book that focused on agriculture in Nigeria. For a researcher this was an important milestone. The other highlight is contributing to the development of IITA’s regional hub for East and Central Africa in Tanzania. I am also lucky to have greatly contributed to mentoring young professionals at IITA and training of many in social science in Africa. Some of them are working as colleagues in international organizations or as professors in universities. What changes have you noted at IITA over the years? I have noticed many changes, all positive. The institute has really grown, becoming more stable. Financially, we have moved from an annual budget of $35 million to the current $50 million. And IITA rates well in research and quality of science among the CG centers. I have also witnessed the decentralization of our research activities. When I first joined, everything was done from Ibadan. The decentralization has brought the scientists closer to the fields of operation outside West Africa. For many years, IITA was considered an institute for West and Central Africa. This is no longer the case.
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How can the institute sustain its growth and progress? We need to consolidate our research in the decentralized mode of operations to strengthen the regional hubs but not at the expense of West Africa. We also should not ignore the reforms taking place in the CG. We need to see how the institute can evolve in the new consortium of CG centers. What would you like social science at IITA to look like, say in five years time? I would like to see a more diversified group of social scientists. We need to strengthen the areas of qualitative social science research and on markets. The current thinking is that one economist can do all research related to social science. I disagree. For example, can one breeder breed all crops? At IITA we have breeders of maize, cassava, cowpea, and yam, etc. So, when it comes to social research, we need a diversified group of social scientists. Socioscience is also wanting at the NARS where the social scientists are always lured away by better-paying NGOs. We build their capacity but when they are ready they move on and we have to start again when they recruit new members. One solution is to link up with universities where we have more permanent social scientists.
What has contributed to your success? I attribute my success (if any) to the support I receive from the management. They have always made me feel that my work is important and that it is valued. I also would like to acknowledge the support and collaboration with partners and colleagues within and outside the institution. On research management, I am part of a great team where members support one another. We have good leadership and good support from management. I have also been lucky to work in my area of expertise. What would you have been if not an agricultural economist? Well, I resisted a lot of pressure from my family to study medicine and become a medical doctor. I have always liked agriculture. I moved 2,000 km from my home town in Lubumbashi (DRC) to study agriculture at the then unique country Faculty of Agriculture in Kisangani. The person who stoked my interest in agricultural economics was Prof Eric Tollens, currently at KU Leuven (Belgium) and a former IITA Board member. When I joined the Faculty of Agriculture in Kisangani, he was then a professor and chair of the Department of Agricultural Economics. I listened to his talk, and I knew what I wanted to be.
Experimental cowpea field, IITA. Photo by C. Ono-Raphael, IITA.
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Ousmane Boukar: Cowpea improvement for food security and poverty alleviation Ousmane Boukar is IITAâ&#x20AC;&#x2122;s cowpea breeder and the Station Representative in Kano, Nigeria. He has been with IITA since 2007. As a breeder, his aim is to mine IITA's germplasm collection of cowpea to identify important additional sources of gene(s) of interest for resistance to both biotic and abiotic stresses, sources of consumers and producers' preferred traits, etc. This will broaden cowpea's genetic diversity to contribute efficiently and significantly to cowpea genetic improvement. Please describe your work. My work in IITA is exciting and very challenging. IITA offers a lot of opportunities to contribute to the livelihood of millions of people mainly in sub-Saharan Africa through the improvement of the agriculture sector. I believe that playing a role in cowpea improvement means participating in enhancing food security and poverty alleviation of millions of people in Africa. What are the current thrusts and initiatives on cowpea breeding? The cowpea breeding program is focused on identifying additional sources of resistance to pests and diseases, combating parasitic weeds, improving drought tolerance and adaptation to low soil fertility. Our strategy is to consolidate the progress so far achieved and to establish a very strong foundation for further genetic improvement. The aim is to increase production in terms of both fodder and grain yields, and those plant and grain characteristics preferred by consumers and producers. Efforts would also be made to enhance the level of micronutrients and protein in cowpea grains. African rural and sub-urban communities will be able to produce more high quality products for human and animal consumption, to improve
their health by providing a balanced diet, and their income by providing enough for home consumption and supply to markets. Major projects associated with cowpea improvement include Tropical Legumes I and II, Purdue Improved Cowpea Storage, Development and promotion of Alectra-resistant cowpea cultivars, the Application of marker-assisted selection for Striga resistance in cowpea, Improving drought tolerance phenotyping in cowpea, Appropriate Variety of Early maturing Cowpea for Burkina Faso (AVEC-BF), and Development of parasitic weed control methods for world food security. What are the major challenges in cowpea improvement? Cowpea production is limited by numerous factors both biotic and abiotic which could be addressed using the tools from genetic improvement. Several diseases, insect pests, nematodes, and parasitic weeds cause significant cowpea yield loss. Abiotic constraints include drought and heat which also cause significant yield reduction during
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the seedling and/or reproductive stages of the crop. Another major production constraint is low soil fertility from organic matter and low phosphorus availability, particularly in the soils of the savannas. The range of production environments and cropping systems and the diverse preferences among consumers and producers for grain, leaves, pods, and fodder, make cowpea breeding very challenging. There is a clear need to develop a range of varieties that meet the diverse requirements combining high yield potential and resistance to the major production constraints. How do you decide which challenges to address? Identification of areas of research involves all stakeholders along the cowpea value chain. We consider both the current and long-term needs of our stakeholders. The current needs are determined from observations in our research fields, farmersâ&#x20AC;&#x2122; fields, the attitudes of consumers, and in our interactions with farmers, NARS colleagues, NGOs, traditional and political leaders through farmersâ&#x20AC;&#x2122; field days, farmers' participatory varietal
selection, and participation in meetings. The long-term needs are based on our own experiences and those of colleagues. This approach guarantees the continued relevance of our research activities. The various projects enable me to have a good interaction with all the stakeholders. Who are IITAâ&#x20AC;&#x2122;s partners in cowpea improvement research? NARES, advanced research institutions (ARI), NGOs, farmers, traditional and political leaders. Our activities on drought tolerance, for example, involve national and international partners (Mali, Niger, Nigeria, Mozambique, Tanzania, Burkina, and Senegal; and University of California, Riverside). Our Striga and Alectra research activities involve both NARS (Burkina, Senegal, Niger, Mali, and Cameroon for Striga and Malawi and Tanzania for Alectra) and ARIs (University of Virginia for Striga and Natural Resources Institute for Alectra). Our partners are involved right from the initial stages of the projects. Why is cowpea underexploited and underutilized? The main reason is that cowpea is a crop grown by poor people for
Farmers' participatory varietal selection, northern Nigeria. Photo by IITA.
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consumption and commercial value in the local regions. This makes the crop unattractive to commercial breeding and seed companies and ensures a lower priority for developed countries.
this variety has impressed farmers in Mali who named it jiffigui which means “hope”. Additional adaptation trials are being conducted in Mali and Niger for the release of this line.
Sub-Saharan Africa accounts for 70% of the world cowpea production. What could be done to ensure that cowpea receives research attention? Almost all African governments consider agriculture as the main basis of their economic development. Very good strategies are being developed but unfortunately these strategies are not followed through always! Funding for cowpea research will enable the research institutes and universities to compete for external funding. Very few governments are supporting their research institutions by facilitating contacts or lobbying through major donors.
Another example is IT00K-1263. This has shown good performance in Mozambique and Tanzania and is being considered for release soon in these countries. Additional sources of improved P-use and resistance to aphids, bacterial blight, multiple virus, Striga, and drought have been identified and segregating populations have been developed. New breeding lines with drought tolerance and multiple disease, and insect and Striga resistance will be available in the near future.
What new tools are being used to hasten cowpea improvement work? With the rapid advances in plant genomics and molecular biology, new tools are being developed. Also, the use of molecular breeding combined with conventional breeding is becoming possible in cowpea improvement. A few steps are already being applied in cowpea improvement through marker-assisted selection and genetic modification. With the development of the recent well-saturated consensus genetic map, cowpea improvement is ready to benefit from an increased efficiency of selection resulting from the application of molecular breeding. Tropical Legume I phase II will soon give us an opportunity to test the efficiency and effectiveness of molecular breeding in cowpea. What are the recent developments and breakthroughs in cowpea breeding that farmers and producers, including processors, could look forward to? Our intensive activities through the Tropical Legumes II project have led to the identification and release of some drought-tolerant breeding lines. For example, in 2008, IT97K-499-35 was released in Nigeria. The performance of
How do you involve farmers and producers in your work? Through farmers' participatory variety selection (FPVS). This consists of bringing groups of farmers to the field where they can select 2 to 3 varieties that they prefer out of about 20−30 lines. Varieties developed through this approach have showed a higher rate of adoption by the farmers. In addition, farmers' field days and baseline studies enable us to learn from farmers about their main production constraints and their preferences in terms of plant type, maturity type, and grain and fodder quality. All the information collected is being incorporated in our breeding objectives. How could IITA make stakeholders pay more attention to cowpea? For more than four decades, IITA scientists had been working on different aspects of cowpea improvement. By documenting the role of cowpea in the livelihood of people in sub-Saharan Africa, the importance of major cowpea production constraints, the progress so far achieved, and strategies for the future, and by maintaining the world’s collection of germplasm for this crop IITA will continue to make donors and other stakeholders more interested on cowpea. Email: o.boukar@cgiar.org
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looking in
Irvin E. Widders: Perspectives on CRSP training
Irvin E. Widders is the Director of the Dry Grain Pulses Collaborative Research Support Program (CRSP) based in Michigan State University (Program Management Entity). Irvin has directed the Pulse CRSP since 2007 and the Bean/Cowpea CRSP from 2000 to 2007. He provides technical leadership to the program and monitors the technical performance of subcontracted projects so as to ensure that the program achieves its global objectives and development goals. He also serves as the primary link with program advisory groups and cultivates collaborative partnerships with institutions involved in pulse research and technology transfer in developing countries of sub-Saharan Africa and Latin America, as well as with private pulse industry groups. The Pulse CRSP is supported by the USAID. It is one of the organizers of the 5th World Cowpea Research Conference currently being held in Saly, Senegal. Tell us about the Dry Grain Pulses CRSP. The Dry Grain Pulses CRSP aims to contribute to economic growth and food and nutritional security through knowledge and technology generation on pulses (e.g., common bean, cowpea, pigeon pea, lima bean, etc.); sustainable growth, and competitiveness of pulse value chains using socially and environmentally compatible approaches; empowerment and strengthened capacity of agriculture research institutions in countries in Africa and Latin America; USAIDâ&#x20AC;&#x2122;s development objectives as defined by the Feed the Future Initiative; and dual benefits to developing country and US agriculture. What are its objectives? The Pulse CRSPâ&#x20AC;&#x2122;s objectives are to (1) reduce bean and cowpea production costs and risks for enhanced profitability and competitiveness, (2) increase the use of bean and cowpea grain,
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food products, and ingredients so as to expand market opportunities and improve community nutrition and health, (3) improve the performance and sustainability for bean and cowpea value chains, especially for the benefit of women, and (4) increase the capacity, effectiveness, and sustainability of agriculture research institutions that serve the bean and cowpea sectors and developing country agriculture in sub-Saharan Africa and Latin America. Why a CRSP on pulses? The international community of scientists in the Dry Grain Pulses CRSP believes that cowpeas are a strategic solution to the global challenges of nutritional security, worldwide climate change, and the sustainability of cropping systems. Cowpea is a staple food, providing fresh peas, leaves, and nutrient-dense dry grain to countless
millions of people in Africa, Asia, and Latin America. It is highly tolerant of drought and high temperatures; it biologically fixes nitrogen and generates an economic return for small-scale resource-poor farmers. What are some of the exciting initiatives of CRSP? Current research and outreach initiatives are undertaken in partnership with national agriculture research systems and agricultural universities in Africa that benefit stakeholders of cowpea value chains. These include the following: a. The use of â&#x20AC;&#x153;omicsâ&#x20AC;? tools to deploy and manage biological controls for insect pests on cowpea in West Africa. b. The breeding and dissemination of cowpea varieties with drought tolerance, resistance to economically important biotic constraints and improved grain culinary quality traits. c. The determination of the influence of natural phytochemical constituents of cowpeas on metabolic, cardiovascular, and chemo-protective human health predictors in in-vitro systems. d. The assessment of the effects of cowpea and bean consumption by HIV-
infected children (through nutritional interventions) on nutritional status and CD-4 counts. Please explain CRSPâ&#x20AC;&#x2122;s approach to capacity building Capacity building of host country collaborating institutions is central to the mandate of the CRSPs since their inception in the early 1980s. The CRSP approach is to empower host country institutions to address agricultural constraints and opportunities through the creation of new technologies and knowledge while concurrently developing human resource capacity and competencies in strategic areas of agricultural science. This leads to institutional self-reliance and sustainability. The CRSPs support the efforts of NARS, agricultural universities in developing countries, and international agricultural research centers to enhance capacity through human resource development, professional consultations, and facilities and infrastructure improvement. The need for additional professionals to contribute to the development of pulse value chains is never ending. New professions are needed in diverse
Farmer field school in Niger. Photo from I. Widders.
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disciplines to provide leadership to the continued development and competitiveness of the cowpea and bean sectors. What is CRSP’s strength? Institutional capacity building is an area where US universities, through the CRSPs, have comparative advantage over other development programs. US universities are academic institutions in the business of human resource development; educating and preparing leaders to face the challenges of an ever-changing and complex world. Universities can effectively design and implement innovative, flexible, and costeffective institutional capacity building initiatives as well as professional development programs. What are some of CRSP’s achievements? If one looks over cowpea and bean research in Africa and Latin America, one would be impressed with the impact of the Bean/Cowpea (1980-2007) and the Dry Grain Pulses CRSP on human resource development—perhaps our greatest legacy. It is estimated that nearly 680 individuals received Master’s and PhD degrees with full or partial support through these CRSPs. The encouraging news is that over 60% of CRSP trainees are back in their home countries and continue to work in support of the cowpea and bean sectors. The most valuable knowledge/skill/ attitude acquired through the CRSP training was “the ability to design, conduct, and analyze scientific research” as a result of being mentored by a CRSP university professor. What are some of CRSP's challenges? The program has yet to achieve its intended developmental outcomes and impact. Small-scale resource-poor pulse (cowpea) farmers are still struggling to provide for household food and nutritional security needs, as revealed by the recent food crisis (http://www. feedthefuture.gov/FTF_Guide.pdf). The keys to success in technology transfer and to catalyzing the growth of cowpea value chains are complex and often unique for each situation.
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The greatest challenge is to achieve sustainable improvements in various sectors of a value chain. It is relatively easy to place quality seeds of improved varieties of cowpea in the hands of large numbers of farmers. However, it is extremely challenging to develop sustainable seed systems in which pulse farmers assume responsibility for the production of quality declared/certified seeds at an affordable price. Many programs have also been unsuccessful in getting farmers to recognize the value of planting quality seeds of specific improved varieties that will provide yield increases, provide grain of types demanded by markets, and with desired culinary traits, thus justifying an increased price and a willingness to pay for “improved seeds”. How could collaborative programs be more effective in addressing the needs of partners and farmers? It is imperative that all programs supporting research and technology transfer efforts on pulses (e.g., cowpea), including the private sector, cooperate to ensure more focused attention to priority constraints, to identify technologies and policies that will enable small-scale farmers to compete in domestic and regional markets, and to coordinate their strategy and activities. To be successful in stimulating the development and growth of functional and sustainable pulse value chains in Africa and Latin America, governments and donors must continue to make balanced investments in both research and technology transfer. Recent advances in science afford opportunities to greatly benefit small holder pulse/ cowpea farmers. The cowpea research community must, however, assume greater responsibility to work directly with private sector groups and NGOs to ensure that future outputs of research are appropriate and are extended to the target beneficiaries. Email: widders@msu.edu
James M. Lowenberg-Deboer: Ensuring Africa's future through agriculture James M. Lowenberg-DeBoer, or Jess, has 24 years of worldwide experience in agricultural research, teaching, outreach, and administration. He currently serves as Associate Dean and Director of International Programs in Agriculture (IPIA) at Purdue University, coordinating all international programs for the Purdue College of Agriculture. His research focuses on the economics of agricultural technology. He brings to his research, teaching, outreach, and administration a perspective gained through private sector experience as a farmer and journalist. Please describe your work. I have participated in every step of the cowpea value chain in Africa from production to consumption. I have helped cowpea breeders define their genetic strategy, collaborated with entomologists on pest management in cowpea fields, partnered with extension specialists to transfer improved cowpea storage technologies, and worked with food scientists to reduce the labor required to make cowpea-based street foods. I have even initiated some exploratory research on the economics of cowpea leaves as a green vegetable. Most recently, I focused on the Purdue Improved Cowpea Storage (PICS) project, teaching farmers and cowpea traders how to use hermetic storage methods to reduce damage without insecticides and developing the supply chain for the heavy duty plastic bags that are, in most cases, the most costeffective hermetic storage container. How important is cowpea in the American diet and economy? Cowpea is a specialty item in the American diet and economy. It is commonly known as “black-eyed peas” in the US because the varieties found
in supermarkets are usually white with black eyes. Many Americans eat cowpea in traditional dishes associated with holidays. For instance some Americans eat “hopping john”, a dish made of cowpea and rice on New Year’s Day. “Southern peas,” cowpea that is picked before maturity and eaten as a vegetable, are widely consumed in the Southeastern US. Some families have heirloom cowpea seed varieties that are passed down from parents to children, and grown each year in the household garden. On US farms cowpea is a specialty crop grown on roughly 92,000 ha annually. Dry cowpea grain is produced on only about 12,000 ha annually, mostly in California and Texas. Southern peas are produced mostly in the southeastern
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US, mainly in home and market gardens. Because they are not a largescale commercial crop, the government does not collect statistics on production, but informal estimates indicate that up to 80,000 ha of cowpea in the US is used annually as southern peas. How did you get started in cowpea research? I started working on cowpeas when I was a researcher at the National Institute of Agricultural Research of Niger (INRAN) from 1988 to 1992. Niger exports more cowpea than any other country in the world. The crop is very important for the Nigerien economy and for Nigerien farmers. In West and Central Africa, the demand for cowpea is very strong, particularly in Nigeria. Farmers could increase cowpea production with the assurance that there would be a market for their product. Urban people, particularly the urban poor, benefit from cowpea because it is a relatively low-cost, high-protein food that does not require refrigeration. Improvement in cowpea production, storage, and marketing would benefit millions of people. In short, cowpea research allowed me to maximize my impact as a scientist. Please describe your collaborative work with IITA. I have worked with almost every IITA cowpea researcher. For example, B.B. Singh and Ousmane Boukar used the consumer preference research done by my students and I do to help determine the goals of their breeding efforts. I collaborated with Ousmane Coulibaly to assess the reactions of potential producers and consumers to genetically modified cowpea. Over many years, I have worked closely with Tahirou Abdoulaye, most recently in assessing the impact of the PICS project. What are the major constraints in cowpea research and development? Twenty years ago when I started working on cowpea issues, farmers
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usually said that their most pressing problem was storage. They said that they would produce more cowpea if only they could store it safely until they needed it for household consumption or until prices made marketing profitable. Today, farmers in the current PICS countries usually say that management of field insects is their major problem. They say that PICS has provided a cost-effective solution to the storage problem. It is hard to predict which cowpea constraint will be the most serious in the future, but I think we should pay attention to two issues: soil fertility and consumersâ&#x20AC;&#x2122; demand. In general, African soils are becoming degraded. Like most legumes, cowpea is very sensitive to soil phosphate levels. World phosphate stocks are decreasing and the price of phosphate fertilizer is trending upward. We should think about breeding cowpea varieties that make better use of the phosphates in the soil and we need to consider how to recycle urban wastes and livestock manure to return the phosphates from cowpea grain and forage to the soil. Any other concerns? My concern about cowpea demand is related to economic growth. In many countries in the world, when incomes rise, people want more animal-based protein and more convenient foods. For instance, in some Latin American countries, consumption of beans per capita is declining as people switch to meat, milk, and eggs. For economic, nutritional, and environmental reasons, it is important that people everywhere continue to consume grain legumes, especially cowpea. In West and Central Africa, that means we need to educate consumers on the benefits of eating cowpea and we need to work with food scientists to develop labor-saving forms of traditional cowpea-based foods. For example, we hope that our work on coarse cowpea flour can be used to make cowpea
fritters (i.e., akara or kossai) or cowpea dumplings (i.e., dan wakĂŠ) without the laborious traditional wet milling process. This will help to keep cowpea foods in family meals and on street vendorsâ&#x20AC;&#x2122; stalls. What do you think is the future of cowpea in Africa? Cowpea is a great grain legume crop for the low-altitude tropics. Because it is very heat and drought tolerant, cowpea is ideal for semi-arid areas. The single greatest threat to the future of cowpea in Africa is that it will be displaced by other crops that have greater research backing. For example, soybean benefits from the extensive research done in the US, China, Japan, and other temperate zone countries. To a lesser extent, the same is true for the common bean. In spite of cowpeaâ&#x20AC;&#x2122;s natural advantages, African farmers may be obliged by economic forces to switch to producing other crops for which research develops greater heat, drought, resistance to pests and diseases; and crops for which food science and marketing develop alternative high-value uses. The future of cowpea in Africa depends on maintaining and developing a research community that will allow this species to fulfill its potential. How could farmers and producers cash in on cowpea? African farmers are already cashing in on cowpea. In the Sahelian countries, cowpea is often the only viable cash crop. If science finds a solution to the field pest management problems, we can expect a much greater production in the humid zones of West and Central Africa. To realize profits on cowpea with current technology, farmers have improved varieties, soil fertility management methods, pest management techniques, and storage technologies. They need to determine which combination works for them. Like farmers in industrialized countries,
Interviewing cowpea vendor in Accra, Ghana. Photo from J. Lowenberg-DeBoer.
African producers of cowpea need to be attentive to new technology. Economics dictate that the biggest benefits from new technology go to the early adopters. How would you describe your experiences in working in Africa? I have worked on every continent which has agriculture. My work in Africa has been the most professionally and personally satisfying. I think this is because in Africa the need is great and the potential is even greater. Per capita food production in Africa has been declining for decades, but Africa is also the area with the greatest potential for increased food production. In the rest of the world, most of the land that can be farmed is already farmed intensively. In Africa, land that is farmed is mostly cultivated with the most extensive methods and there is still land to be developed for agriculture. Africa is the future of agriculture and agribusiness. I am pleased to have played a small role in the research that is building African agriculture and a slightly larger role in training the African scientists who will help Africa to realize its agricultural potential. Email: lowenbej@purdue.edu
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f r o n tiers New approaches to assessing soil conservation options Birte Junge, Birte.Junge@web.de
Land degradation has become a global concern as it affects the environment, agronomic productivity, food security, and quality of life (Eswaran et al. 2001). Due to rapid population growth, land use has been intensified to cover the increased demand for food. This often results in the loss of soil and nutrients when land is not used properly. Processes that degrade soil include the loss of topsoil by the action of water or wind; chemical deterioration, such as nutrient depletion; physical degradation, such as compaction; and biological deterioration of the natural resource which includes, among others, the reduction of soil biodiversity (Lal 2001). In Nigeria, where the population dramatically increased from 115 million in 1991 to 140 million in 2006 (FRN 2007), human-induced soil degradation is a common phenomenon: its severity is low for 37.5% of the area (342,917 km2), moderate for 4.3% (39,440 km2), high for 26.3% (240,495 km2), and very high for 27.9% (255,167 km2) (FAO 2005). Soil erosion is the most widespread type of soil degradation in the country and has long been recognized as a serious problem (Stamp 1938). In 1989, 693,000 km2 were already characterized by runoff-induced soil loss in the south. In the north, 231,000 km2 were degraded, mainly by wind erosion. Sheet erosion is observed all over the country. Rill and gully erosion are common in the east and along
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rivers in northern Nigeria (Ologe 1978, Igbozurike et al. 1989). Soil erosion degrades the natural resource base, resulting in the loss of land for farming or grazing animals, as well as off-site problems, such as the sedimentation of dams. Reduced agricultural production, food insecurity, low income for the rural population, and poverty are some of the consequences. Thus, more emphasis has to be put on avoiding soil loss through improved management to conserve the natural resources for today and the future. Monitoring land use intensification and soil degradation A German Federal Ministry for Economic Cooperation and Development/German Society for Technical Cooperation (BMZ/GTZ) project from 2005 to 2008 included the study of soil erosion and its causes using different methodologies, such as remote sensing and the geographic information system (GIS) technology. Aerial photos and satellite images produced at different dates and scales and GIS can be used to obtain key information on environmental resources and their degradation (Oluseyi 2002). Badume (12°19'N 8°31'E), Kayawa (11°22'N 7°20'E), Gadza (8°98'N 6°00'E), and Eglime (7°08'N 1°67'E), villages located in different agroecological zones of Nigeria and Bénin, were selected as study sites. Historical aerial photos (from 1962, 1981, or 1982) and recent satellite
images (IKONOS imagery with spatial resolution of 1 m from 2000; and QuickBird imagery with spatial resolution of 0.6 m from 2005 to 2007) were analyzed to study the change in land use/land cover (LULC) and soil degradation in these places. A manual interpretation approach was used to identify the LULC classes of the study areas. Verification was done in the field with local farmers and by using the global positioning system (GPS) to obtain the accurate location of the former and present village boundaries and to get point data for the LULC classes. In addition, the average growth rate of several gullies in each village was measured for use in forecasting possible expansion in the future.
1962/1981
2005
Change in LULC The interpretation of historical and recent remote sensing data showed that the area of all settlements expanded within the last decades and years. For example, the village of Badume increased from 0.9 ha (1962) to 4.3 ha (2006), an expansion of 3.4 ha in 44 years. The rate of increase was slower in former times than in recent years. This reflects the recent rise in population. The area in use around the pilot villages also expanded within the period considered. For example, the area of Kayawa increased from 166.8 ha to about 438.6 ha, an expansion of 272.6 ha in 44 years. The rate of increase was much higher in former times than in recent years, with more of the uncultivated land available around the settlements being converted into farmland. No uncultivated land was/is available for expansion any longer, since the borders with neighboring villages had been reached. The areas covered with trees or shrubs generally decreased in the pilot villages. For instance, in Gadza, the area decreased by 4.8 ha from 2000 to 2005. Causes are conversion into farmland,
2005/06/07
Remote sensing data: aerial photograph, IKONOS, and QuickBird. Photos from B. Junge.
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Legend —— 1949 —— 2000
Change in village area from 365 ha (1949) to 402 ha (2000), Badume, Kano State, Nigeria. Area increased by 137 ha. Image from B. Junge.
but also the uncontrolled exploitation of these areas for fuelwood (Odihi 2003), timber (Okoro 1990), or logging (Omo-Irabo and Odunyemi 2007). The reduction or elimination of fallow was especially observable in Badume and Kayawa, but not so severe in Gadza where fallow still covered a certain percentage of the village area. The reason might be the production of cash crops in inland valleys—the “fadama”— which ensures a certain income. Uncultivated areas in the surroundings of the fields also decreased during the period under consideration. Having less land is a constraint to livestock production for the Fulani (migrant farmers) who need to graze their animals. Conflicts between arable farmers and pastoralists already take place in the pilot villages because of competition for limited land resources. Change in soil degradation The study sites located in the Sudan and northern Guinea savanna were characterized by sheet erosion. In Badume, the eroded area near the river sites increased from 11.6 ha in 2000 to 12.3 ha in 2006. In Kayawa, sheet erosion was a big problem, especially in the western part of the village area.
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Land characterized by sheet erosion (7.9 ha) was already visible on the photo in 1962 and increased to 32.3 ha in 2006. Erosion gullies were also detected along the rivers in the uncultivated area of Badume and Kayawa. The study of two gullies located northeast of the village area of Badume revealed that the degraded land increased from 37.9 ha (2000) to 45.1 ha (2006). In Kayawa, gully erosion also increased. In 1962, about 1.5 ha of the village area was destroyed by gullies. This area increased to 13.1 ha in 2000 and to 15.5 ha in 2006. Reasons include the high impact of the rain at the beginning of the wet season after the total removal of crop residues during the dry season (Odunze 2003) and the formation of ridges along the slope that increase the velocity of runoff and hence, the removal of topsoil (Lal 1995). The herds of cattle that graze on the land or pass it on their way to watering pits or other pastures are very destructive. The frequent shortage of grass, overgrazing, and trampling by animals result in a sparse vegetation cover that exposes bare soil and accelerates the formation of runoff and the removal of topsoil (Azeza and Omeji 1985).
The uncultivated area surrounding Gadza was characterized by a huge network of deeply worn animal tracks mainly located between a Fulani settlement and the Gadza River. These pathways were carved to different extents, depending on their location and the frequency of animal passage. During heavy rain, the transport of runoff and sediment was observed, resulting in the removal of fine particles and the accumulation of sand and gravel. In 2000, about 17 km of track-gullies already existed; this increased to 83.7 km in 2005. This immense increase of 66.7 km in 5 years might be caused by the higher resolution of the recent QuickBird images which facilitated the detection of small tracks. Another reason might be the increase in the number of cattle causing these linear erosion features. No erosion gullies were detected on the aerial photograph of Eglime made in 1982. This might be caused by the small scale of the picture and its bad quality, as elderly farmers remember the presence of some erosion features from their childhood. In 2000, gullies with a total length of 4.4 km were observed
and this total increased to 42.2 km in 2007. Reasons for this big increase are the good quality of recent images and the change in LULC. The farm area has increased within the last decades with the promotion of cotton cultivation. This crop is known for its low canopy cover and, hence, for reduced protection of the soil surface against the impact of rain drops (Junge 2004). Based on calculated gully growth rates, the estimation of possible future expansion of areas degraded by gully erosion showed an increase for all pilot villages, but to different extents. In Badume, 3.0 ha and in Kayawa, 4.7 ha are expected to be eroded in 10 years. The gullies in Gadza, developed from animal tracks, will cover an area of about 1.2 ha in the following decade, and in Eglime, 2.3 ha of land will be lost to gully erosion. Using remote sensing and GIS The interpretation of remote sensing data produced at different dates and of pilot villages in different agroecological zones of Nigeria and BĂŠnin has shown that the village area, farmland, and settlement expanded at all sites.
Present gully erosion, Badume, Kano State, Nigeria, 2000 (Left) and 2006 (right). Area increased from 37.9 ha to 45.1 ha, or an increase of 7.2 ha. Images from B. Junge.
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Farmland increased at the expense of areas usually covered with forest and shrubs, fallow, and grazing land. The consequences of this land use intensification were detected in all study sites in the form of sheet and gully erosion. The removal of soil including organic matter and nutrients inevitably resulted in the decrease of arable and grazing land, reduced production of crops, meat, and milk products, and reduced income for the local farmers. If no measures to conserve the natural resources are implemented in the near future, the increase in soil deterioration will continue. Land scarcity will follow with related conflicts between the users, food insecurity, and poverty. The generation of an environmental database and the mapping of LULC and existing soil degradation are the bases for improved natural resource management. Detailed surveys are therefore recommended to intensify the land use inventory to generate an environmental database in Nigeria. This would include information on present LULC and the extent of soil degradation. Land use plans should also be developed illustrating the areas used for agriculture (farming and pasturing), urban development, industry, and commercial purpose. Information of these kinds are a useful tool for policymakers and land use planners and would contribute to an enhanced management of the environment in Nigeria and Bénin. References Azeza, M.I. and M.U. Omeje. 1985. Soil erosion control measures in the Sahel. In Proceedings of Conference National Workshop on Ecological Disasters in Nigeria: Drought and Desertification. 9–12 December 1985. Kano, Nigeria. pp. 377–379. Eswaran, H., R. Lal, and P.F. Reich. 2001. Land degradation: an overview. In Responses to Land Degradation, edited by E.M. Bridges, I.D. Hannam, L.R. Oldeman, F.W.T. Pening de Vries, S.J. Scherr, and S. Sompatpanit. Proceedings of the 2nd International Conference on Land Degradation and Desertification, Khon Kaen, January 1999. New Delhi: Oxford Press. http://soils.usda.gov/use/
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FAO, AGL. 2005. Global Assessment of the Status of Human-Induced Soil Degradation (GLASOD). http://www. fao.org/landandwater/agll/glasod/glasodmaps.jsp. FRN (Federal Republic of Nigeria). 2007. Official Gazette: Legal Notice on publication of the details of the breakdown of the National and State provisional totals 2006 Census. Government Notice Nr. 21. Nr. 24. Vol. 94. Lagos. Igbozurike, U.M., D.U.U. Okali, and A.T. Salau. 1989. Profile on Nigeria: Land Degradation. Report submitted to Commonwealth Secretariat, London. Friedrich Ebert Foundation, Lagos, and Nigerian Environmental Study/ Action Team (NEST), Ibadan, 48 pp. Junge, B. 2004. Die Boeden des oberen OuemeEinzugsgebietes in Benin/Westafrika – Pedologie, Klassifizierung, Nutzung und Degradierung. PhD dissertation, University of Bonn, Germany. 291 pp. Junge B., T. Alabi, K. Sonder, M.Subash, R. Abaidoo, D. Chikoye, and K. Stahr. 2009. Use of remote sensing and GIS for monitoring changes of land use/land cover and environmental degradation in different agroecological zones of West Africa. Int. J. Remote Sensing. (in press) Lal, R. 1995. Sustainable management of soil resources in the humid tropics. United Nations University Press. New York, USA. 593 pp. Lal, R. 2001. Soil Degradation by Erosion. Land Degradation and Development 12:519–539. Odihi, J. 2003. Deforestation in afforestation priority zone in Sudano-Sahelian Nigeria. Applied Geography 23(4):227–259. Odunze A.C. 2003. Northern Guinea savanna of Nigeria and rainfall properties for erosion control. African Soils 33:73–116. Okoro, S.P.A. 1990. Status of forest resources of Nigeria. Paper presented at the 20th Annual Conference of the Forestry Association of Nigeria. 25–30 November 1990, Katsina, Nigeria. Forestry Association of Nigeria. 20 pp. Ologe, K.O. 1978. A quick preliminary survey of soil erosion in northwestern Nigeria. Report for the Land Resource Division of the Federal Department of Agriculture, Kaduna. 18 pp. Oluseyi, F.O. 2002. Integration of remote sensing data and field models of in-situ data in a GIS for environmental sensivity index mapping; a Nigerian example. Available online at: http://www.isprs.org/commission4/ proceedings02/pdfpapers/464.pdf (accessed 28 July 2008). Omo-Irabo, O.O. and K. Odunyemi. 2007. A hybrid image classification approach for the systematic analysis of land cover (LC) changes in the Niger Delta Region. Available online at: http://www.itc.nl/ISSDQ2007/proceedings/ Session%202%20Spatial%20Statistics/paper%20 omoleomo.pdf (accessed 27 July 2008). Stamp, L.D. 1938. Land utilization and soil erosion in Nigeria. Geographical Review 28:32–45. Tappan, G. and M. Cushing. 2004. Use of SCL-Off Landat image data for monitoring land use/ land cover trends in West Africa. USGS EROS Data Center, Sioux Falls, SD, USA. 11 pp.
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Edition 5, September 2010
The IITA R4D Review is a six-monthly magazine intended to help IITA and research and development partners, investors, collaborators, and beneficiaries discuss and develop the best new ideas for people creating, leading, and transforming tropical agriculture in sub-Saharan Africa and beyond. The R4D Review has six sections: Features provides an in-depth, rigorous presentation of a significant advance in researchfor-development thinking and its application to real world needs that help establish an intellectual agenda for discussion—and change— within the organizations and for society at large. Best Practice describes the how and why behind a successful research for development achievement. Tool Box provides a nuts-and-bolts explanation of a useful research-for-development tool that can be translated into action in many different situations. Who’s Who recounts a personal story of an IITA staff that contains lessons for colleagues. Looking In features people from outside IITA whose ideas hold salient lessons for those within IITA. Frontiers is a forum for forward-looking articles that explore new science and technology trends affecting development needs (i.e., starting projects or technologies in the pipeline).
CONTRIBUTIONS needed The R4D Review is looking for new sources of solid, useful ideas that can improve researchfor-development practice. Please submit your contributions or participate in the R4D Review interactive site at www.r4dreview.org. The general guidelines for contributions are also available at this site. Prospective authors can also send submissions, communications, comments, and suggestions to: The Editor, R4D Review. Headquarters: IITA, PMB 5320, Ibadan, Nigeria Mailing address: IITA, Carolyn House, 26 Dingwall Road, Croydon CR9 3EE, UK Telephone: (234 2) 751 7472, (1 201) 633 6094 Fax: (234 2) 241 2221 www.iita.org
www.r4dreview.org
September 2010
Edition 5
R4D Review
Participate in the interactive online R4D Review at
www.r4dreview.org
ISSN 2071-3681