Looking into the dynamics of Musa production in Africa

A banana valley near Ruhengeri, Rwanda. Photo by Piet van Asten, IITA.
A banana valley near Ruhengeri, Rwanda. Photo by Piet van Asten, IITA.

This year, we undertook research to further und Ralph Lauren Mens Polo Shirts Australia off started with  erstand the dynamics of the relationships among factors affecting banana and plantain production in Africa such as pest and diseases, biotic and abiotic stresses, and farmers’ preferences. This is to establish some of the underlying causes why bananas and plantains in Africa are as they are. More importantly, this would help us plot a more effective course for our Musa research-for-development efforts.

In East Africa, we conducted large-scale diagnostic surveys with our partners particularly in the major production areas of Uganda, Rwanda, Burundi, Eastern DRC, and central Kenya. We mapped yield levels, crop management practices, pest and disease pressure, nutrient deficiencies, and ecological parameters such as rainfall and altitude.

Our surveys came up with some surprising facts:

  • Yield levels (t/ha), taken from measurements of hundreds of farmers fields, were more than double the figures reported by national statistics and cited by FAO;
  • Uganda, which has been traditionally regarded as the regional champion of banana production, actually had lower average yields (around 15 t/ha) than neighboring Rwanda, Burundi, and East DR Congo (more than 20 t/ha);
  • Sigatoka disease pressure, which had been the primary focus of breeders, was generally low, especially in the higher altitudes;
  • Nematode and weevil pressure was still important in the lower parts of the highlands (less than 1200m above sea level), but were not a primary yield constraint in most production areas;
  • Nutrient deficiencies were widespread. With the exception of young and volcanic soils near the Albertine rift, the dominant Acricols and Ferralsols were low in nutrient stocks.; and
  • Soil organic matter management is a key factor, and often explained the large production differences observed when moving 50 meters away from the relatively fertile soil adjacent to houses to banana plots farther away and less likely to receive discarded kitchen waste.
Banana being transported via truck in Uganda. The farther the farms are from markets, the lesser the incomes farmers get. Photo by Piet van Asten, IITA.
Banana being transported via truck in Uganda. The farther the farms are from markets, the lesser the incomes farmers get. Photo by Piet van Asten, IITA.

Our on-farm fertilizer trials across Uganda showed that modest fertilizer doses (average 71N, 8P, 32K kg ha-1 yr-1) doubled yields from 10 to 20 t/ha per year in areas such as Central Uganda. Fertilizer use proved highly profitable near large urban centers such as Kampala, but at farther distances (>150km) from the market, the increased transport cost reduced farm gate prices to levels that would make fertilizer investments too risky (marginal rates of return <100%).

Besides soil fertility, regional production gradients seemed also strongly correlated to rainfall gradients. To prove this, we explored data from past field trials, relating inter-annual yield variations to rainfall variations. Drought proved to be one of the biggest yield constraints, with an estimated 50% yield loss in large production areas in the highlands that received ”only” 1000 mm of rainfall per year. Pot trials confirmed that even moderate drought stress (pF 2.8) resulted in strongly reduced growth (>63%) compared to pla stole helene de shopbust baugigny  nts that remained well watered (pF 1.8). Drought stress does not result in obvious visual stress symptoms, explaining why farmers and researchers in the East African highlands had not given it much attention.

We are planning to conduct similar diagnostic surveys for the plantain systems in West and Central Africa, as well as setting up irrigation trials in West and East Africa, in 2010.

Our plant health researchers are also conducting studies to probe deeper into the complex relationships between pest and disease resistance and abiotic and biotic stresses, and develop appropriate solutions to optimize Musa production in Africa.

New aflatoxin-resistant maize

A local partner holding a cob of aflatoxin-contaminated maize. Photo by Godwin Atser, IITA.
A local partner holding a cob of aflatoxin-contaminated maize. Photo by Godwin Atser, IITA.

Aflatoxins, poisons produced by th Ralph Lauren Mens Polo Shirts Australia wide portions  e fungus Aspergillus flavus, infect agricultural commodities such as groundnuts, cassava, yam, and maize. They pose serious potential health hazards to both humans and animals, and have far-reaching negative implications on the global trade contaminated crops (see related article “Towards safer African food crops” under Agriculture and Health).

Various solutions have been proposed to minimize aflatoxin contamination in food crops. Host resistance remains as the most widely explored strategy as A. flavus infects susceptible crops before harvest.

Our researchers in partnership with colleagues from the US Department of Agriculture – Agricultural Research Service (USDA-ARS-SRRC) have developed and released six new maize inbred lines with resistance to aflatoxin contamination and adapted to the lowlands. These lines, named TZAR101 through TZAR106, have also been registered in the United States. The research was co-funded by FAS-USDA-ARS, USAID, and IITA.

Collaborating for almost a decade, USDA-ARS plant pathologist Robert Brown and IITA maize breeder Abebe Menkir developed the new maize lines through conventional breeding by crossing the best aflatoxin-resistant lines found in the US (GT-MAS:gk, MI82 and Mp420) with tropical elite lines found in Central and West Africa (1368, 4001 and KU1414-SR).

Aside from demonstrating good resistance against aflatoxin accumulation under laboratory and field tests, most of these new maize lines also possess other commercially-desirable traits and resistance to diseases such as leaf blight and southern corn rust.

As these inbred lines involve parents of both tropical and temperate origin, they are likely to contain new combinations of complimentary alleles imparting resistance to aflatoxin accumulation. These can be exploited by maize breeders as new  may shopbust be b lace which  sources of resistance for developing maize cultivars with higher levels of resistance to A. flavus infection/aflatoxin contamination.

They can also serve as sources of resistance to foliar diseases as well as desirable agronomic traits to expand the genetic base of adapted US and tropical maize germplasm to accelerate the development of productive new cultivars. The resistant lines with good agronomic traits could be used as parents to accelerate breeding efforts against aflatoxin contamination of national programs in West and Central Africa.

New soybean offers respite from deadly Asian rust

Asian rust-resistant TGx 1835-10E, at right, compared to a susceptible variety. Photo by IITA.
Asian rust-resistant TGx 1835-10E, at right, compared to a susceptible variety. Photo by IITA.

The Asian soybean rust is a fungal disease that is capable of laying waste as much as 80 percent of infested crops. This year, a soybean variety resistant to the disease that we developed was approved for release by the Nigerian National Variety Release Committee (NNVRC). The rust-resistant soybean is the first of its kind to be made available for cultivation not only in Nigeria but also in West and Central Africa.

Tagged TGx 1835-10E, our scientists bred the variety and further developed it in collaboration with the National Cereal Research Institute. Its release for general cultivation was approved in December 2008 and notified in June 2009 by the NNVRC.

Field trials in Nigeria showed that aside from being resistant to the Asian rust, the variety is also high-yielding, averaging 1655 kg/ha grain and 2210 kg/ha fodder. It is also early-maturing, has good promiscuous nodulation character, and resists pod shattering and other prevalent diseases.

The variety can be used for direct cultivation in tropical Africa or as a source of resistance genes in soybean breeding programs. It was previously released in Uganda through the initiative of Makerere University, a local partner, and has already shown excellent performance in trials carried out in Southern Africa, suggesting that it is well-adapted.

Its resistance is effective against all currently known types of the rust fungus in Nigeria. We have bred several other lines with rust resistance genes from various sources, which can be deployed quickly if this variety succumbs to newer forms of the rust fungus.

It was in 1996 that the Asian soybean rust first arrived in Africa, rapidly spreading through Uganda, Malawi, Mozambique, Rwanda, South Africa, Zambia and Zimbabwe. The disease was first noted in Nigeria in 1999.

The causal fungus of the Asian soybean rust, Phakopsora pachyrhizi, is very aggressive and can produce billions of spores capable of turning lush green crops with healthy foliage into brown fields with bare stalks in 2-3 weeks.

For most African farmers, using resistant varieties is the most viable method to control the disease as applying fungicides proves very costly.

Opportunities from crises

Growing vegetables is hard work - from preparing the land to watering the plants twice a day. Photo by Arnstein Staverlokk, Bioforsk.
Growing vegetables is hard work - from preparing the land to watering the plants twice a day. We are continuously finding ways to make life easier and better for African farmers. Photo by Arnstein Staverlokk, Bioforsk.

In 2009, most of the world was still on unstable footing due to the lingering effects of the double-whammy–the global financial breakdown and the food price crisis–that hit the previous year. For millions of African farmers and their families, the negative impacts of these crises were still strongly felt. As if these were not enough, the third threat of climate change resulting in shifting weather patterns is making agricultural production much more unpredictable and volatile, making the lives of growers even harder.

However, these crises presented us with terrific opportunities to demonstrate the effectiveness of our research-for-development (R4D) strategy. Working closely with partners and with the support of our investors, we developed viable options to help African farmers mitigate and cope with the effects of these threats.

Below is a summary of our R4D highlights and achievements in sub-Saharan Africa for 2009. Details of these highlights and achievements are presented in the “Research Highlights” section of this annual report:

To address vitamin A deficiency especially among women and children in Africa, we gave tropical maize a boost of the nutrient by combining it with maize from the temperate zones containing high levels of beta-carotene and pro-vitamin A. The result was maize that is not only more nutritious but is also well-adapted to the tropical conditions of sub-Saharan Africa.

We were also able to produce a fungus-based biocontrol product against aflatoxin contamination in major African food crops. Called aflasafe, the product has been proven to significantly reduce aflatoxin contamination in maize in our field trials in Nigeria. The product has been granted a provisional registration by the Nigerian government, allowing us to further test it in more areas. We are also trying to develop a similar product for application in Burkina Faso and Senegal.

Mid-year, we sent our second shipment of seeds of African crops to the Svalbard Global Seed Vault. This comprised of about 5000 seed samples of soybean, maize, bambara nut, cowpea, and African yam bean. Through our Genetic Resources Unit, we are continuing efforts to expand our germplasm collection to help ensure the security and future of Africa’s agrobiodiversity.

We developed new diagnostic tools to help check the spread of crop disease-causing pathogens. Called ‘DNA Barcoding’, this new initiative could genetically characterize pathogen populations and recognize unique stretches of sequences. The DNA ‘barcodes’ could then be used as markers to diagnose pathogens and pests affecting African food crops.

In the face of the rapid onslaught of two deadly diseases of bananas and plantains in Africa – Banana Xanthomonas Wilt and Banana Bunchy Top Disease – that is threatening to wipe-out the crops from the continent, we engaged in a number of complementary disease-management research. These include conducting diagnostic assays, regional disease surveillance, developing management tools, and studying host-plant resistance.

We also undertook studies to delve deeper into the dynamics of Musa production in Africa. This included research that looked at relationships between and among pests and diseases, biotic and abiotic stresses, and farmers’ preferences. All of these to establish the underlying causes of the present state of Musa production in Africa, and enable us to plot a more effective course for our R4D work on bananas and plantains in the continent.

Further to our work on developing a biocontrol product against aflatoxin contamination in food crops, we also developed six new aflatoxin-resistant maize inbred lines with our US-based partners. These maize lines, which have been released to farmers, are also well-adapted to the lowlands.

Our work on improved double-purpose cowpea has resulted in significant increases in the incomes of farmers in northern Nigeria. Cowpea growers in that part of the country have seen their farm profits jump by as much as 55 percent from using the improved varieties compared to local ones.

On soybeans, we developed a new variety that is resistant to the deadly Asian rust – a disease that causes as much as 80 percent crop loss in infested fields. Tagged TGx 1835-10E, the new rust-resistant variety is also high-yielding, bringing an average of 1655 kg/ha of grain and 2210 kg/ha of fodder. It also possesses other traits sought after by soybean farmers.

Our project on “Promoting Sustainable Agriculture in Borno State” (PROSAB), which ended it five-year run this year, showcased the effectiveness of our R4D approach. Our post-project socioeconomic analysis have shown that the poverty levels of about 17,000 households, or more than 100,000 participating farmers, have dropped by an average of 14 percent, while food security improved by about 17 percent – due mainly to PROSAB’s R4D interventions.

Our Sustainable Tree Crops Program (STCP) was tapped as one of five technical partners of a global, multi-sector consortium to implement the US$40 million, 5-year Cocoa Livelihoods Program (CLP). The program is funded by the Bill & Melinda Gates Foundation and 14 chocolate industry companies. STCP will lead the CLP’s site selection, develop and validate training approaches for cocoa farm rehabilitation, produce appropriate training materials, establish a community-level distribution system for improved planting materials, conduct market opportunity and product diversification studies, and manage the program’s Performance Coordination Unit.

A study on the impact of agricultural research on productivity and poverty in sub-Saharan Africa that we completed this year has shown that agricultural research has a direct positive impact on poverty, reducing the number of poor people in the region by as much as 2.3 million annually. In view of the long-term research investments and demonstrated successes in the region, our own R4D work is helping uplift the lives of about 500,000 to one million poor people in sub-Saharan Africa annually.

This year, we moved even closer to developing cassava that has dual resistance to two of the crop’s deadliest diseases – Cassava Mosaic Disease and Cassava Brown Streak Disease. We are currently conducting further disease-stress tests and breeding on candidate cultivars that have shown promise. We are also ensuring that traits sought after by farmers – such as cooking taste, texture, and yield – are addressed.

Yam farmers in sub-Saharan Africa have been traditionally beset by high production costs. We developed a novel way of propagating yam that does away with using tubers as seeds, saving farmers as much as 25 to 30 percent in production expenses. The innovative technique involves using vine cuttings grown in inexpensive carbonized rice husks to produce mini-tubers, which are then used as the planting material in the fields. Aside from reducing costs, this new yam propagation technique could also address the need for faster and wider distribution of disease-free and improved varieties to farmers.

For years, cabbage farms in West Africa have been suffering from the damage inflicted by the Diamondback Moth (DBM), affecting farmers’ incomes and market prices of the high-value crop. This year, we developed a biopesticide based on a fungus– Beauveria bassiana – that effectively controls DBM. Used in integrated pest management, the biopesticide offers a cost-effective and ecologically-friendly alternative to inorganic pesticides, which are not only expensive but also poses health risks to humans and the environment. The B. bassiana-based biopesticide has been tested and proven effective in a number of field tests in the Benin Republic.

We carried out advanced studies in the biological control of the cowpea pod borer, Maruca vitrata. We further evaluated the effectiveness of a previously identified natural enemy of the pod borer, the parasitoid Apanteles taragamae. We also continued host-range studies of the Multi-Nucleopolyhedrosis Virus, another promising biocontrol against Maruca vitrata, which was found through collaborative studies with the World Vegetable Center.

To service more African farmers, we established our Southern Africa Administrative Hub in Zambia to backstop our R4D efforts in that part of the continent. The hub will cater to the agricultural research support needs of Zambia, Malawi, Mozambique, Zimbabwe, Lesotho, Swaziland, Botswana, Namibia, South Africa and, as needed, the DR Congo. With the establishment of our Southern Africa hub, our administrative support system now have three focal points: West Africa (covered by IITA-Nigeria), East Africa (serviced by IITA-Tanzania), and Southern Africa (covered by IITA-Zambia).

Our 2009 audited financial statements reflect the institute’s sustained financial health and stability, and the prudent management of resources. Our liquidity and reserve levels are above those recommended by the CGIAR, indicating our continued ability to meet short- and long-term obligations. Please see the “Financial Information” section of this report for details.

PROSAB: demonstrating the effectiveness of our R4D approach

Some members of a women farmers' group organized under PROSAB are all smiles, proud of what they have achieved under the project. Photo by Amare Tegbaru, IITA.
Some members of a women farmers' group organized under PROSAB are all smiles, proud of what they have achieved under the project. Photo by Amare Tegbaru, IITA.

The successes recorded by the five-year run of the “Promoting Sustainable Agriculture in Borno State” (PROSAB) project that we coordinated proved the effectiveness of our research-for-development (R4D) approach in tackling not only livelihoods and food security but also social empowerment and gender equality. PROSAB started in 2004 and ended this year.

Farmers in the project area who adopted the technologies and management practices espoused by the project experienced increased food availability and incomes. Considerable progress was also made in addressing the problems of declining soil fertility and Striga infestation.

Our socioeconomic analysis involving about 17,000 households, or more than 100,000 farmers, that participated in the project showed that poverty levels dropped by an average of 14 percent, while food security improved by 17 percent.

Farmers who participated in the project increased their average incomes by an average of 81 percent compared to what they were earning before PROSAB started. They attributed this mainly to the project’s interventions.

More importantly, the knock-on effect on other non-participating farmers in the region has been tremendous.

PROSAB seed producer Marcus Dawi Mbaye. He was able to put his four children through university from the income he earned from the various agro-projects under PROSAB. Photo by Amare Tegbaru, IITA.
PROSAB seed producer Marcus Dawi Mbaye. He was able to put his four children through university from the income he earned from the various agro-projects under PROSAB. Photo by Amare Tegbaru, IITA.

PROSAB introduced improved crop varieties, trained farmers on improved agronomic practices and promoted gender equality in agricultural development.

Apart from reducing poverty in households from 63 percent to 49 percent, the project also made significant inroads in enhancing women’s roles in agricultural activities.

Ruth Dasika Mshelia, a mother of five and a participant of the project, attested, “PROSAB has helped us freely interact with our male counterparts in development projects. We are not ashamed anymore,”

Borno state, where the project was centered, is predominantly Islamic, with social interaction between men and women largely restricted by religious norms.

Farmers, policy makers, nongovernment organizations, and other local partners hailed it as a major success story in northern Nigeria where climatic and cultural factors are major challenges to development.

Some local governments have signified interest in out-scaling PROSAB’s approach to other states. It has also been touted as a model that could be adopted in agriculture-based communities in other African countries.

The CA$ 7 million (about US$6.33 million) project was funded by the Canadian International Development Agency. Our implementing partners included the International Livestock Research Institute, Borno State Agricultural Development Program, Community Research for Empowerment and Development, the Institute of Agricultural Research – Zaria, and the University of Maiduguri.

STCP in the Cocoa Livelihoods Program

Cocoa seedlings ready for distribution to growers in a community nursery established by IITA/STCP. Photo by Richard Asare, IITA.
Cocoa seedlings ready for distribution to growers in a community nursery established by IITA/STCP. Photo by Richard Asare, IITA.

This year, our Sustainable Tree Crops Program (STCP) was tapped to be part of a multi-sector consortium to implement the US$40 million, 5-year Cocoa Livelihoods Program (CLP). The CLP, managed by the World Cocoa Foundation, aims to improve the livelihoods of approximately 200,000 cocoa farmers in Cote d’Ivoire, Ghana, Nigeria, Cameroon and Liberia by addressing marketing and production inefficiencies, income diversification, and farming technology/innovations.

The program was first announced in February 2009. Activities began following intensive site selection that we led in consultation with public and private sector partners in the project countries. We would also be training cocoa farmers in production practices and quality management through innovative approaches such as Farmer Field School, Farmer-to-Farmer training, and Video Viewing Clubs.

We would develop and validates a new training approach that would help rehabilitate existing cocoa farms through the proper establishment of productive systems of high yielding, fertilizer-responsive varieties. We will also develop distribution systems for improved planting material in the five countries by facilitating the establishment of commercial and on-farm nurseries, and clonal budwood gardens for rehabilitation through grafting. These nurseries will serve as sources of high-yielding planting material for cocoa and other crops and trees.

To ensure that the nurseries are supplied with the best available cocoa, timber, plantain, and cassava planting materials, we would develop a community-level brokerage service that would link communities and commercial nurseries to various suppliers. We will also explore the Farmer Organization and the Business Service Center approaches to ensure the availability and accessibility of input supply for farmers.

We are currently conducting a market opportunity study in the five countries to analyze diversification opportunities in local, regional, and international markets using a common economic and financial analytical framework. The study covers cocoa, cassava, and plantain and their associated inputs, with other key country-specific commodities also to be considered. It would provide vital market information to reduce the risk of an income shock on the economies of these countries and its spillover impact on cocoa-growing communities.

We are also responsible for managing the Performance Monitoring Coordination Unit (PMCU) of the CLP. The PMCU coordinates the monitoring activities of the five technical partners to ensure consistency and accuracy of data collected. The PMCU will maintain a centralized information database, and provide data to partners as needed to promote informed decision-making within the program.

The CLP is funded by the Bill & Melinda Gates Foundation and 14 chocolate industry companies. Aside from IITA/STCP, the other four implementing partners include Agribusiness Services International – an ACDI/VOCA affiliate, Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ) GmbH, Société de coopération pour le développement international (SOCODEVI), and TechnoServe. The program has been launched in Ghana, Cote d’Ivoire and Nigeria, and is expected to be launched in Cameroon and Liberia soon.

Guiding farmers toward profitable, eco-friendly and sustainable cocoa production

Cocoa farmers breaking pods. Photo by Cynthia Prah, IITA.
Cocoa farmers breaking pods. Photo by Cynthia Prah, IITA.

Cocoa production North Face UK Outlet f   in West and Central Africa is generally low. Average yields are about 200-700kg per hectare. Surveys conducted by STCP show that as much as 40 percent of farmers in the region are at the losing  end of growing cocoa.

To enhance productivity, old and nonportlandhallhotel -productive farms need to be rehabilitated, or new cocoa farms established using best agronomic practices. In 2007, we conceived the idea of developing a comprehensive and compact manual on ecologically-friendly, profitable, and sustainable cocoa production practices that could be used to build the capacity of farmers.

In consultation with growers and cocoa experts from national and regional partner institutions across West Africa, we developed the Planting, Replanting and Diversification (PRD) Manual – a cocoa production training document that is based on mutual participatory learning between farmers and experts.

Cover page of the IITA/STCP PRD Manual. Image provided by Cynthia Prah, IITA.
Cover page of the IITA/STCP PRD Manual. Image provided by Cynthia Prah, IITA.

The PRD Manual is designed to help sharpen the skills and knowledge of farmers in carrying out best practices to rehabilitate old farms and/or start new ones. The manual uses the Farmer Learning Group approach, which is a structured, group-based learning methodology that that focuses on practical demonstrations, hands-on field exercises, and discussions to hone farmers’ skills.

To help farmers use the manual, we also developed an accompanying guidebook entitled Implementing Guide for Planting, Replanting and Tree Diversification in Cocoa Systems.

These resources are already being extensively used in farming communities in Ghana, Cote d’Ivoire, Nigeria, Cameroon, and Liberia. Hundreds of farmers in these countries have benefited from their use and the initial outcomes have been encouraging.

The manual and guide are expected to contribute towards the regeneration of cocoa farms across West Africa, and consequently improve the plight of farmers in the region. They are available online as downloadable PDFs from the STCP Web site.

Agricultural research uplifts lives

A yam trader happily showing off his ware. With appropriate agricultural infrastructure, input, and policy support, Africa can indeed feed itself. Photo by IITA.
A yam trader happily showing off his ware. With appropriate agricultural infrastructure, input, and policy support, Africa can indeed feed itself. Photo by IITA.

A study on the impact of agricultural research on productivity and poverty in sub-Saharan Africa (SSA) that we completed this year has shown that agricultural research has a direct positive impact on poverty, reducing the number of poor people in the region by as much as 2.3 million annually.

According to the study, in view of the long-term research investments and demonstrated successes in SSA, our own R4D work is helping uplift the lives of about 500,000 to one million poor people in the region per year.

The study, authored by Arega Alene, Impact Assessment Economist, and Ousmane Coulibaly, Agricultural Economist, also estimated that the aggregate rate of return to agricultural research in the region runs as high as 55 percent.

However, the study cautions that the actual impacts are not large enough to offset the poverty-increasing effects of population growth and environmental degradation in the region.

The study, which has been published in the journal Food Policy, further demonstrated that doubling investments in agricultural R&D in SSA from the current US$650 million annually could reduce poverty in the region by two percentage points per year. However, the study adds that this projected drop in poverty would not be realized unless existing extension, credit, and input supply systems become more efficient.

The study also established that agricultural research had contributed significantly to productivity growth in SSA, with the highest payoffs noted in Ghana, Cameroon, Nigeria and Ethiopia. This is attributed to sustained investments in building national research capacity, long-term operations of the Consultative Group on International Agricultural Research (CGIAR), North Face Jacket Sale UK and regional technology spillovers. Work by the CGIAR contributed about 56% of the total poverty reduction impact in the sub-region.

Despite the contributions of agricultural research, the study notes that SSA faces several unique constraints outside the research realm that hinder the realization of potential benefits. It singled out weak extension systems, lack of efficient credit and input supply systems, and poor infrastructure development. The study recommended that concerned entities undertake efforts to improveNorth Face Sale these systems and related infrastructure, and increase investments in agricultural research, to further reduce poverty in SSA.

Developing dual-resistance cassava

Cassava root rot caused by CBSD. Photo by IITA.
Cassava root rot caused by CBSD. Photo by IITA.

This year, we moved closer to developing North Face Sale a few too mild properly and so forth!
cassava with dual resistance to Cassava Mosaic Disease (CMD) and Cassava Brown Streak Disease (CBSD) – the most devastating diseases of the crop in Eastern and Central Africa and the greatest threats to the food security and livelihoods of over 200 million people.

In Uganda, we selected eight clones with resistance to CMD and CBSD and other farmer-preferred traits. These clones, which are the first ones with dual resistance suitable to the mid-altitude areas of the Great Lakes regions, were sent to the Kenya Plant Health Inspectorate Services for cleaning and multiplication in preparation for regional distribution to national partners. An additional 41 yellow-fleshed clones, also with dual resistance to CMD and CBSD, are undergoing advanced evaluation.

This is the fourth year of trials for dual-resistance cassava for mid-altitudes in Uganda. The trials are being conducted in Mukono and Namulonge, considered hot spots of CBSD and CMD in the country. The breeding work started with over 5000 true seeds of parents with tolerance to CBSD from Tanzania that were sent to Uganda for crossing with IITA varieties that are resistant to CMD.

Cassava grown from the Tanzanian seeds were repeatedly subjected to high disease pressure along with susceptible varieties for comparison. From each growing season, only 10 percent of the crop was selected for the next stage. After four growing seasons, the field has been narrowed down to eight very promising varieties.

Similar dual-resistance evaluation was carried out in Tanzania. Eight clones that have resistance to both CMD andeducate North Face Jacket Sale yourself on the way th much CBSD were deliberately subjected to the diseases by grafting them with infected plants. Five of these clones are being evaluated on-farm, while 11 clones with dual resistance and high starch content – a preferred trait by farmers – are also being evaluated.

Cassava that survives these tests, thereby producing a true dual-resistant variety, can then be used for further disease-resistance breeding in other countries in the Great Lakes region such as Rwanda, Kenya, and DR Congo. Throughout the selection process, farmers were actively engaged to ensure that the varieties meet their preferences such as cooking taste, texture, and yield.

A novel way to propagate yams

A rooted yam vine cutting, which would soon be ready for transplanting in the field. Photo by O Adebayo, IITA.
A rooted yam vine cutting, which would soon be ready for transplanting in the field. Photo by O Adebayo, IITA.

In the traditional method of growing yam, appearance dryfarmers set aside 25 to 30 percent of the harvested tubers as seeds for the next planting season. This makes the crop expensive to produce. It is also inefficient: the multiplication rate is only about 1:5-10, which pales in comparison, for instance, to cereals that have a propagation ratio of about 1:300.

To address these constraints, we developed an time her helps someone innovative yam propagation technique using vine cuttings. In this method, cuttings, usually one to two nodes with leaves are taken from the lateral branches of immature healthy-looking vines before tuber enlargement, and planted into soil with carbonized rice husks (CRH).

Once the cuttings formed roots and shoots, they are transplanted to nursery beds where they are nurtured for 150 days. During this time they will produce mini tubers, which are then used as the planting material for the next crop.

We are testing this novel technique in a number of farmers’ fields in Nigeria’s north central Niger state. The technology has been extensively featured in a number of broadcast and print media in Nigeria, Japan and the UK, and some countries in sub-Saharan Africa and Oceania.

By reducing the use of ware tubers as seeds, more yams are made available to farmers for food or for sale. The technique also promotes faster multiplication and better and more uniform crop quality by introducing a break in the cycle of nematode infestation often associated with regular use of field-grown tubers as planting material.

Another advantage of this technology is that the rooting medium, CRH, could be obtained by farmers cheaply, even for free.

Previously, we developed another propagation method together with the National Root Crops Research Institute of Nigeria based on mini-setts: yam tubers are cut up into 20-25 g pieces and used to produce planting material for ware tuber production.

Compared to using whole tubers, mini-setts enable faster multiplication and lesser amount of planting material needed. The use of vine cuttings further improves on this pace of multiplication and reduces the amount of need planting material even more. The technology could address the need for faster and wider distribution of disease-free improved varieties to meet rising demand.

The research is funded by the Japanese government, the Sasakawa Africa Association, Tokyo University of Agriculture, and the International Cooperation Center for Agricultural Education, Nagoya University, Japan.