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Theme: Environmental health and biodiversity

The world needs better management of water, soil, nutrients, and biodiversity in crop, livestock, and fisheries systems, coupled with higher-order landscape considerations as well as circular economy and agroecological approaches.

CIMMYT and CGIAR use modern digital tools to bring together state-of-the-art Earth system observation and big data analysis to inform co-design of global solutions and national policies.

Our maize and wheat genebanks preserve the legacy of biodiversity, while breeders and researchers look at ways to reduce the environmental footprint of agriculture.

Ultimately, our work helps stay within planetary boundaries and limit water use, nutrient use, pollution, undesirable land use change, and biodiversity loss.

Ten years later: CIMMYT facilities in East Africa continue to make a difference

Written by Julian Bañuelos-Uribe on . Posted in News.

CIMMYT and partners in Kenya recently marked the 10th anniversary of two major facilities that have been crucial for maize breeding in sub-Saharan Africa. The Maize Doubled-Haploid (DH) facility and the Maize Lethal Necrosis (MLN) screening facility at the Kenya Agriculture and Livestock Research Organization (KALRO) centers in Naivasha and Kiboko, respectively, have made immense contributions to the rapid development of higher-yielding, climate-resilient and disease-resistant maize varieties for smallholder farmers across the continent.

An aerial photo of the Naivasha Research Center. (Photo: CIMMYT)

“These two facilities have been instrumental in furthering KALRO’s mission to utilize technology in the service of Kenya’s smallholder farmers,” said KALRO Director General/CEO, Eliud Kireger. “They also exhibit the spirit of cooperation and collaboration that is necessary for us to meet all the challenges to our food systems.”

“Deploying a higher yielding maize variety may not be impactful in eastern Africa if that variety does not have resistance to a devastating disease like MLN,” said CIMMYT’s Director General Bram Govaerts. “These two facilities demonstrate the holistic methods which are key to working towards a more productive, inclusive and resilient agrifood system.”

Maize DH facility

Hybrid maize varieties have much higher yields than open-pollinated varieties and are key to unlocking the agricultural potential of maize producing countries. The doubled haploid process is an innovative technology producing within a year genetically true-to-type maize lines that serve as building blocks for improved maize hybrids.

Unlike conventional breeding, which takes at least 7 to 8 generations or crop seasons to develop parental lines, DH lines are generated within two seasons, saving significant time, labor and other resources. DH maize lines are highly uniform, genetically stable, and are more amenable to the application of modern molecular tools, making them perfect resources for breeding elite maize hybrids.

Workers in the Kiboko Double Haploid facility. (Photo: CIMMYT)

The aim of CIMMYT’s maize DH facility is to empower the breeding programs throughout the low-and middle-income countries in Africa by offering a competitive, accessible, not-for-profit DH production service that will accelerate their rate of genetic gain and fast-track development of improved maize varieties for farming communities.

Since 2017, the DH facility has delivered 280,000 DH lines from 1,840 populations of which 20% were delivered to public and private sector partners. CIMMYT maize breeding programs and partner organizations have embraced the use of DH technology, with many of the newest maize hybrids released in Africa being derived from DH lines. The facility has also served as a training ground so far for over 60 scientists and hundreds of undergraduate students in modern breeding technologies.

“Before 2013, DH technology was mainly employed by private, multinational corporations in North America, Europe, Asia and Latin America,” said CIMMYT’s DH Facility Manager, Vijay Chaikam. “But the DH facility operated by CIMMYT at the KALRO Kiboko research station is specifically targeted at strengthening the maize breeding programs by the public sector institutions as well as small-and medium-size enterprise seed companies in Africa.”

The maize DH facility at Kiboko, Kenya, was established with funding support from the Bill & Melinda Gates Foundation and inaugurated in September 2013. The facility includes an administrative building, seed quality laboratory, training resources, artificial seed dyer, a cold-storage seed room, a chromosome doubling laboratory, greenhouse and a state-of-the-art irrigation system to support year-round DH production in the 17-hectare nursery.

MLN screening facility

MLN is a devastating viral disease that can decimate farmers’ fields, causing premature plant death and unfilled, poorly formed maize ears, and can lead to up to 100 percent yield loss in farmers’ fields. Though known in other parts of the world for decades, the disease was first identified in eastern Africa in 2011. By 2015, MLN had rapidly spread across eastern Africa, including Kenya, Uganda, Tanzania, South Sudan, Rwanda, Democratic Republic of Congo and Ethiopia. CIMMYT scientists quickly discovered that almost all the commercial maize cultivars in eastern Africa were highly susceptible to the disease.

Against this backdrop, CIMMYT and KALRO recognized the urgent need for establishing a screening facility to provide MLN phenotyping service and effectively manage the risk of MLN on maize production through screening of germplasm and identifying MLN-resistant sources. The facility was built with funding support from the Bill & Melinda Gates Foundation and the Syngenta Foundation for Sustainable Agriculture, and inaugurated in September 2013.

Resistant and susceptible line at the Maize Lethal Necrosis facility. (Photo: CIMMYT)

“The MLN screening facility is a key regional resource in breeding for resistance to a devastating viral disease. The facility is indeed one of the key factors behind successful management of MLN and helping stem the tide of losses in eastern Africa,” said Director of the Global Maize Program at CIMMYT and One CGIAR Plant Health Initiative, B.M. Prasanna. “Fighting diseases like MLN, which do not respect political boundaries, requires strong regional and local collaboration. The successes achieved through the MLN Screening facility in the past 10 years embody that spirit of collaboration.” Indeed, farmers in the region now have access to over twenty genetically diverse, MLN-tolerant/resistant maize hybrids released in eastern and southern Africa.

The facility is the largest dedicated MLN screening facility in Africa and has evaluated over 230,000 accessions (over 330,000 rows of maize) from CIMMYT and partners, including over 15 national research programs, national and multinational seed companies. The facility covers 20 hectares, of which 17 hectares are used for field screening of germplasm. Dedicated laboratories and screen houses cover the remaining 3 hectares.

“MLN phenotyping service is conducted under stringent quarantine standards and the high-quality data is shared with all the CGIAR and public and private partners. The MLN screening service has helped breeding programs across the continent, aided in undertaking epidemiological research activities, and supported capacity building of students from diverse institutions, and regional stakeholders regarding MLN diagnosis and best management practices,” said CIMMYT’s Maize Pathologist in Africa, L.M. Suresh.

“The output of MLN resistant lines and hybrids has been remarkable,” said Director of Phytosanitary and Biosecurity at the Kenya Plant Health Inspectorate Service (KEPHIS), Isaac Macharia. “And the facility has strictly adhered to quarantine regulations.”

In Uganda, the MLN facility was crucial in the “release of the first-generation MLN tolerant hybrids and dissemination of MLN knowledge products that minimized the economic impact of MLN,” said the Director of Research of the National Crops Resources Research Institute, Godfrey Asea.

Peter Mbogo, maize breeder with Seed Co Group, said, “This is the only quarantine facility in the world where you can screen against MLN under artificial inoculation. It has been an excellent return on investment.”

Resilience Building through agroecological intensification in Zimbabwe (RAIZ)

Written by mcallejas on . Posted in Uncategorized.

Zimbabwe’s agricultural sector is predominantly subsistence-oriented, with maize as the main staple crop and limited use of external inputs. To promote sustainable and climate-smart agriculture, Zimbabwe has developed a 10-year framework (2018-2028) that emphasizes the adoption of climate-smart agriculture (CSA). However, the adoption of CSA practices remains limited in the country. Agroecological practices (AE) and the systemic perspective embedded in agroecological approaches hold great potential to address climate change and enhance agricultural sustainable intensification in Zimbabwe. RAIZ was conceived as the research component of the “Team Europe Initiative” (TEI) on “Climate-Smart Agriculture for Resilience Building”, formulated by the European Union (EU) delegation in Zimbabwe together with its member states.

Led by the French Agricultural Research Centre for International Development (CIRAD), in partnership with CIMMYT and the University of Zimbabwe, with funding from the European Union, RAIZ operates along a gradient of declining rainfall from Murewa in Natural Region II to Mutoko in Natural Region IV. Both districts are in the Mashonaland East province. Under RAIZ, CIMMYT leads Work Package 3 which involves ‘developing the capacity of extension and advisory services on agroecological approaches’ is actively involved in research and development activities, including the creation of training materials and the establishment of on-farm trials. In efforts to address challenges associated with low soil fertility on Zimbabwe’s granitic sandy soils. CIMMYT scientists working on RAIZ are testing the contribution of organic fertilizers and conservation agriculture in building up soil organic carbon and bringing back soil life to these mostly dead soils. These efforts aim to support farmers in adopting sustainable and climate-smart agricultural practices, ultimately contributing to the long-term resilience and prosperity of Zimbabwe’s agricultural sector.

Key objectives 

The overall objective is to support government in the development and implementation of scientifically tested agroecological approaches which will enhance agricultural production and resilience to climate change in Zimbabwe.

In addition, the project focuses on protecting the environment and reducing greenhouse gas (GHG) emissions. It will provide scientific evidence and experience for the design of climate-smart agriculture (CSA) at the plot, farm, and landscape levels, contextualized for mixed crop–livestock farms under sub-humid to semi-arid environments.

Response of African sorghum genotypes for drought tolerance under variable environments

Written by mcallejas on . Posted in News, Publications.

New drought-resistant sorghum varieties bring hope for farmers in Africa

Scientists have identified drought-resistant, high-yielding sorghum genotypes that have the potential to revolutionize agriculture in dry regions of Africa. Sorghum, a staple food for millions in sub-Saharan Africa, has long been threatened by devastation from drought.

But now, researchers from the African Centre for Crop Improvement, the Institute of Agricultural Research (IAR), the International Maize and Wheat Improvement Center (CIMMYT), and the University of Life Sciences have discovered genetic resources that thrive under adverse conditions, yielding promising results and providing hope for a future that is more sustainable.

The study looked at 225 sorghum genotypes in various conditions, including non-stressed conditions and pre- and post-anthesis drought stress. The researchers used advanced statistical analysis, such as the additive main effects and multiplicative interaction (AMMI) method, to identify the most resilient and high-yielding genotypes.

The results revealed a vast diversity in the genetic resources of sorghum and provided a pathway for selecting promising genotypes for regions prone to drought. In addition, the study highlighted the significant impact of environmental conditions on grain yield, with genotypes showing variable responses to different growing environments.

A farmer inspecting sorghum on his farm in Tanzania. (Photo: CBCC)

For example, genotypes G144 (Kaura Short Panicle-1) and G157 (Kaura Mai Baki Kona) displayed higher grain yield in drought-stressed environments and were among the top performers. Not only do these genotypes outperform registered cultivars, but they also possess traits valued by farmers, making them ideal candidates for future breeding programs. In addition to drought tolerance, genotypes G119 and G127 displayed remarkable stability and high yield under non-stressed conditions, showing their potential as all-around performers in a variety of environments.

Farmers in dry areas of sub-Saharan Africa that are characterized by pre- and post-anthesis drought stress stand to gain a great deal from these newly identified sorghum strains. Adoption of these high-yielding and drought-resistant genotypes could increase food production and strengthen farmers’ resilience against the effects of climate change.

The findings of these super sorghum genotypes offer farmers facing the challenges of climate change a glimmer of hope. By adopting these new drought-resistant strains, African farmers can improve their food security and strengthen their communities, paving the way for a more resilient and sustainable future.

Sustainable Intensification of Smallholder Farming Systems in Zambia (SIFAZ)

Written by Julian Bañuelos-Uribe on . Posted in Uncategorized.

Sustainable Intensification of Smallholder Farming Systems in Zambia (SIFAZ) is driven by the need to address systemic productivity and sustainability challenges in Zambian smallholder farming systems. This project is implemented in a research-for-development approach where applied research is conducted alongside scaling-up of sustainable and climate-smart crop production and land management practices within selected pilot areas in the three agro-ecological zones (AEZ) of Zambia.

SIFAZ strives to test, promote and enhance the uptake of sustainable intensification practices (SIPs) including mechanization among smallholder farmers while fostering market linkages and creating an enabling environment for sustainable agriculture growth. Such efforts will contribute to the government’s development priorities, which are framed by the Vision 2030 (Republic of Zambia, 2006) of “a prosperous middle-income nation by 2030” including an efficient, competitive, sustainable and export-led agriculture sector that assures food security and increased income.

The SIFAZ project cycles I and II are being implemented by the Food and Agriculture Organization of the United Nations (FAO) in partnership with CIMMYT and the Ministry of Agriculture (MOA) in Zambia, with funding from the European Union (EU) for a period of seven years (2019-2026). Under the SIFAZ project, CIMMYT is leading the implementation of adaptive research and is currently working on establishing on-station and on-farm and field testing in and around three research centers in the southern, eastern and northern provinces of Zambia; the research approach includes co-development of on-farm trials using mother and baby trials; mechanization and socio-economics research.

To achieve this, SIFAZ supports three closely interlinked outputs:

  • Sustainable intensification practices (SIPs) co-developed with farmers and made available for scaling up.
  • Farmers trained, mentored and capacitated to use SIPs, better manage farmer enterprises and engage value chain actors.
  • Enabling institutional and policy environment for scaling and adoption of SIPs by smallholder farmers established.

 

India transforms wheat for the world

Written by mcallejas on . Posted in In the media.

In 2023, India reached a record wheat harvest of over 110 million tons. A partnership between CIMMYT and the Indian Institute of Wheat and Barley Research (IIWBR) now allows farmers to pre-order advanced wheat varieties, transforming the nation’s agriculture.

Read the full story.

The need to consider biological actors as an influence when studying market agencies

Written by Julian Bañuelos-Uribe on . Posted in Publications.

How the living shapes markets: accounting for the action of biological entities in market agencing. Authors: Quentin Chance, Frédéric Goulet and Ronan Le Velly

This article uses research into the organic food market in France to show that biological factors can play an important part in influencing the structure and organization of markets. The authors use this to point out that while many studies of market agencing discuss in detail the role played by social and material agents, biological agents should be an equally important part of such research.

Over the last four decades, there has been considerable research into Actor-Network Theory (ANT), which looks at the effect of various agents on markets. However, in the majority of cases, the agents discussed have been material (for example, shopping trolleys) or social (human habits or economic motives). The research which forms the basis of this article was originally carried out as a study of how French organic-produce collectives tried to influence markets to suit their needs and ideals. On reviewing the data, it appeared to the authors that there were additional agents affecting their marketing, which derived from biological factors. Unlike the material and social agents, farmers were only able to control these biological factors with great difficulty, if at all. For example, the inability to use chemical inputs on crops meant that crop rotation over a multi-year period was essential; however, wholesalers’ traditional structures expected a farmer to supply the same produce in the same quantity year after year. In cases such as this, altered supply chain arrangements needed to be negotiated between the suppliers and the wholesalers.

The authors made four sets of observations showing the market-shaping effect of biological agents.

  • Measures taken by established organic farmers to avoid price competition from new market entrants — the well-established farmers had chosen to start growing crops which required more expertise, time or equipment (such as Belgian endives or onions), rather than less complex standard crops such as potatoes.
  • Biological processes which necessitate altering the traditional market production and supply structures — for example, the need for crop rotation as mentioned above.
  • Natural agents will affect crop yields and introduce variability in quality and quantity, which the market needs to allow for. The authors give examples of pests, viral infections and weather as agents that affect all farming, but in the case of organic farming are particularly troublesome.
  • After harvest, produce will naturally experience ripening/aging, and then degradation in quality. Standard industrial ways of controlling these biological processes utilize methods and agents that are unacceptable or even harmful when dealing with organic produce, for instance, spraying with chemicals.

Following these observations, the authors make a series of propositions and suggest research questions which could result from them, for instance:

  • How does the action of biological entities affect the establishment of market norms/the way prices are set?
  • How do representations of the market take account of biological processes?

In conclusion, the authors demonstrate how the effect of biological agents on markets is already inextricably intertwined with the effects of material and social agents. Future research, to be truly comprehensive, needs to look in equal depth at all other possible influences on the market.

New partnership announced to protect Gorongosa National Park in Mozambique by improving agricultural livelihoods and crop systems

Written by Ricardo Curiel on . Posted in Press releases.

A collaboration scheme launched between the Gorongosa Restoration Project (GRP) and CIMMYT seeks to improve climate resilience, food security and nutrition in Mozambique’s Gorongosa National Park by facilitating the adoption of sustainable practices and giving local farmers access to formal markets and improved value chains.

The partner organizations aim to develop more resilient agrifood systems that contribute to conserve resources and improve the livelihoods of farmers inhabiting the protected area in Mozambique’s Sofala Province.

“Our primary objective is to establish an evidence-based, scalable and replicable model for developing sustainable and resilient agrifood systems in Mozambique that enhance food and nutrition security and climate resilience of local farmers and communities,” said Gregory C. Carr, GRP President.

Gregory C. Carr (left) with Bram Govaerts. (Photo: Ricardo Curiel/CIMMYT)

The parties will explore collaboration opportunities to give local farmers access to drought tolerant and disease resistant varieties and improved seeds by building capacities of local seed systems.

“We are very excited to contribute to protect Gorongosa National Park by restoring soil health, accelerating a transition to resilience and sustainability and improving, as a result, the yields and living standards of local farming communities,” said Bram Govaerts, Director General at CIMMYT.

The new projects will also aim to promote agriculture conservation-based intensification practices that will increase yields sustainably and limit the expansion of the agricultural frontier in the buffer zone neighboring the protected area.

“If you bring two world class organizations together and create critical mass, it is possible to succeed and show that agriculture is not the enemy of biodiversity,” said the U.S. Special Envoy for Global Food Security, Cary Fowler.

Gregory C. Carr (left), Cary Fowler and Bram Govaerts sign a Memorandum of Understanding. (Photo: Ricardo Curiel/CIMMYT)

The 5-year Memorandum of Understanding was signed at the annual Borlaug Dialogue organized by the World Food Prize Foundation, which convenes international thought leaders, development specialists, researchers, farmers, practitioners and authorities from around the world to promote global food systems transformation and food security.

Under this year’s “Harnessing Change” theme, the Foundation presented the prestigious World Food Prize to Heidi KĂŒhn from the United States for her farmer-focused development model that revitalizes farmland, food security, livelihoods and resilience in war-torn regions around the world as a way for restoring peace and prosperity through agriculture.

About GRP

Gorongosa Restoration Project is a poverty alleviation, sustainable development and conservation non-profit organization used by Gorongosa National Park as a development engine for the Sofala region. GRP is a unique organization, with a mission to advance an integrated, multi-partner approach to conservation and people-centered development. While GRP actively protects Gorongosa National Park’s biodiversity and ecosystems, it also strives to unlock its economic potential for the community inhabitants of the Park’s Buffer Zone, former hunting and forestry concessions, Sofala Province and further afield. GRPs dual mandate of biodiversity conservation and human development is undergirded by the principle that the quest for conservation is a human-nature dynamic that must be addressed holistically. This axiom is increasingly supported by conservation science as well as by GRP’s 15 years of experience in the field.

About CIMMYT

CIMMYT is a cutting edge, non-profit, international organization dedicated to solving tomorrow’s problems today. It is entrusted with fostering improved quantity, quality, and dependability of production systems and basic cereals such as maize, wheat, triticale, sorghum, millets, and associated crops through applied agricultural science, particularly in the Global South, through building strong partnerships. This combination enhances the livelihood trajectories and resilience of millions of resource-poor farmers, while working towards a more productive, inclusive, and resilient agrifood system within planetary boundaries.

CIMMYT is a core CGIAR Research Center, a global research partnership for a food-secure future, dedicated to reducing poverty, enhancing food and nutrition security and improving natural resources.

For more information, visit staging.cimmyt.org.

Press contact: Ricardo Curiel, Communications Manager to the Director General, CIMMYT, r.curiel@cgiar.org

IISER Research: Greenhouse Gas Emissions From Crop Residue Burning

Written by mcallejas on . Posted in In the media.

IISER Bhopal, CIMMYT and the University of Michigan have joined forces to harness cutting-edge satellite technology. Their research underscores the urgent need to address this environmental challenge and the critical role of technology in understanding and mitigating the environmental impacts of agricultural practices.

Read the full story.

CIMMYT makes progress on some of the world’s top problems: 2022 Annual Report, “Harvesting Success”

Written by Julian Bañuelos-Uribe on . Posted in News.

CIMMYT targets some of the world’s most pressing problems: ending poverty, ensuring food for the future, mitigating climate change and improving the lives of farmers and consumers (especially women). CIMMYT is a CGIAR Research Center and has long been the world’s leading center for research on maize and wheat. This research capacity is being harnessed to achieve the crucial goals of climate resilience, and food and nutrition security.

Most of the world’s people depend on annual grain crops for their survival. Yet some of the world’s poorest men and women produce cereals. Annual grain farming has exacerbated climate change. The world’s great challenges of achieving climate resilience and nutrition security are being addressed by focusing CIMMYT’s research and development (R&D) on maize, and wheat, as well as on underutilized grain and legume crops.

Highlights from the 2022 Annual Report:

Annual cereal farming tends to release carbon into the atmosphere, while degrading the soil. Improving the soil takes years, and the high annual variation in weather demands long-term experiments. Field trials by CIMMYT over many years show that farmers can return carbon to the soil by using minimum tillage, rotating cereals with legumes, and by applying animal manure and strategic amounts of nitrogen fertilizer. As soil fertility improves, so do farmers’ yields.

Eleven million farmers in India alone produce maize, usually without irrigation, exposing families to climate-related disaster. Twenty new hybrids bred by CIMMYT out-perform commercial maize, even in drought years. One thousand tons of this heat-tolerant maize seed have now been distributed to farmers across South Asia.

Farmer Yangrong Pakhrin shells maize on his verandah in Gharcau, Kanchanpur, Nepal. (Photo: Peter Lowe/CIMMYT)

Some wheat is rich in zinc and iron, which prevent anemia, especially in children. Yet naturally-occurring phytic acid in wheat blocks the body’s absorption of these minerals. A technique developed by CIMMYT lowers the cost of assaying phytic acid, so plant breeders in developing countries can identify promising lines of wheat faster. CIMMYT is also helping to reduce food imports by learning how other crops, like cassava and sorghum, can be blended with wheat to make flours that consumers will accept.

Some wheat hotspots are warm, dry, and subject to plant diseases. CIMMYT collaborates with plant breeders worldwide through the International Wheat Improvement Network (IWIN) to test promising new wheat lines in these tough environments. As more places become warmer and drier with climate change, CIMMYT and allies are developing wheat varieties that will thrive there.

Harvesting more maize in the future will depend on higher yields, not on planting more land. In plant breeding programs in Africa, South Asia and Latin America, CIMMYT and partners are already developing maize varieties and hybrids that will be released in just a few years. A review of these efforts reveals that annual yield increases will be about twice the rate achieved from 1973 to 2012.

Sorghum, millets, pigeon pea, chickpea and groundnuts have been favorite food crops in Africa for centuries. They are already adapted to warm, dry climates. CIMMYT is now working with national research programs to ensure that new crop varieties have the traits that male and female farmers need. Seed systems are being organized to produce more of Africa’s preferred crops.

A group member harvests groundnut in Tanzania. (Photo: Susan Otieno/CIMMYT)

Researchers can only breed new crop varieties if someone saves the old ones from extinction. CIMMYT does that with its world-class collection of wheat and maize seed. In 2022, CIMMYT’s two separate wheat and maize germplasm banks were combined into one. Modern techniques, such as vacuum-sealed seed packets and QR codes, allow rapid response to requests for seed from plant breeders around the world.

CIMMYT is helping Nepali farmers to plant maize in the lowlands, in the spring, when most land lies fallow. In 2022, CIMMYT provided training and investment to 2,260 farmers (35% women), who earned, on average, an additional $367 in one year. The added income allowed these farmers to invest in health care and schooling for their children.

Mexican farmers are saving money, harvesting more and selling their grain more easily. Some 4,000 farmers are now selling on contract to food manufacturing companies. The farmers lower production costs by using CIMMYT innovations in irrigation, fertilizer application and ecological pest control. Yields increase, the soil improves, and farmers find a ready market for their harvest.

The stories we have highlighted in this article are just some of the ones included in the Annual Report. See the full text of all the stories in “Harvesting Success” to learn how CIMMYT scientists are doing some of the most important research, for some of the world’s best causes.

In sub-Saharan Africa, mineral fertilization and agroecology are not incompatible

Written by Julian Bañuelos-Uribe on . Posted in Press releases.

Are agroecological approaches, based for example on the use of legumes and manure, enough by themselves to ensure a long-term increase in annual crop yields in sub-Saharan Africa (SSA), without using more mineral fertilizer?

The answer is no, according to a team of agronomists who have published an in-depth analysis of 150 scientific articles on annual crops (maize, sorghum, millet, rice, cassava, etc.) and tropical legumes, both annual grain legumes (cowpea, groundnut) and legume trees (acacia, sesbania) in tropical environments.

These publications collate 50 years of knowledge on nutrient balances in sub-Saharan Africa, biological nitrogen fixation by tropical legumes, manure use in smallholder farming systems and the environmental impact of mineral fertilizer.

“When we look at comparable climate conditions and physical soil constraints, yields of maize – the main source of calories for people – in sub-Saharan Africa are three to four times lower than elsewhere in the world. This is largely due to the fact that mineral fertilizer use (nitrogen, potassium) is on average four times lower there”, says Gatien Falconnier, a researcher at CIRAD based in Zimbabwe and lead author of the article. “On average, 13 kg of nitrogen are used per hectare and per year in sub-Saharan Africa, for all crops, bearing in mind that the poorest farmers have no access to nitrogen fertilizers and therefore do not use them. It is mainly agri-business and vegetable farmers that have access to fertilizers”, adds François Affholder, an agronomist at CIRAD based in Mozambique and co-author of the article.

Maize and cowpea intercropping in the Maravire field. (Photo: CIMMYT)

“Our objective is not to produce like Europe or North America, but to produce more and more regularly according to the seasons and the years, and thus to increase the economic sustainability of our farming systems. To do so, we must ensure a minimum level of nutrients for crops, which require essential mineral elements for efficient photosynthesis, and therefore growth. Soils are typically lacking in mineral elements in sub-Saharan Africa, and the largely insufficient organic inputs lead to nutrient deficiencies in crops. This is the main limiting factor for crop yields, excluding drought situations”, says Pauline Chivenge of the African Plant Nutrition Institute (APNI). “The work by Christian Pieri showed as early as 1989 that it is possible to restore high levels of fertility to African soils through a balanced approach to organic and mineral nutrient inputs”, says François Affholder.

The article highlights five reasons why more mineral fertilizer is needed in sub-Saharan Africa:

  1. Farming systems are characterized by very low mineral fertilizer use, widespread mixed crop-livestock systems, and significant crop diversity, including legumes. Inputs of mineral elements to crops by farmers are insufficient, resulting in a widespread decline in soil fertility due to soil nutrient mining.
  2. The nitrogen requirements of crops cannot be met solely through biological nitrogen fixation by legumes and manure recycling. Legumes can only fix atmospheric nitrogen if symbiosis with soil bacteria functions correctly, which requires absorption of different mineral elements by the plant. Ken Giller of Wageningen University highlights that the ability of legumes to capture nitrogen from the air through their symbiosis with rhizobium bacteria is a fantastic opportunity for smallholder farmers, “but the amounts on nitrogen fixed are very small unless other nutrients such as phosphorus are supplied through fertilizers”.
  3. Phosphorus and potassium are often the main limiting factors of the functioning of plants and living organisms, including symbiotic bacteria: if there is not enough phosphorus and potassium in soils, then there is no nitrogen fixation. These nutrient elements, phosphorus, potassium and micro-elements, need to be provided by fertilizers, since they cannot be provided by legumes, which draw these elements directly from the soil. In the case of manure, this is simply a transfer from grazing areas to cultivated areas, which gradually reduces fertility in grazing areas.
  4. If used appropriately, mineral fertilizers have little impact on the environment. The greenhouse gas emissions linked to nitrogen fertilizer use can be controlled through a balanced and efficient application. In addition, mineral fertilizers can be produced more efficiently in order to reduce the impact of their production on greenhouse gas emissions, keeping in mind that this impact is low, at around 1% of total anthropogenic emissions.
  5. Further reducing mineral fertilizer use in SSA would hamper productivity gains and would contribute directly to increasing food insecurity and indirectly to agricultural expansion and deforestation. Producing for a population that will double by 2050 is likely to require the use of more agricultural land. An extensive strategy thus harms biodiversity and contributes to increasing greenhouse gas emissions, contrary to an agroecological intensification strategy combined with efficient and moderate mineral fertilizer use.

“If we take account of biophysical production factors, such as climate and soil, and shortages of land and agricultural workers, it will be impossible to reach a satisfactory production level by fertilizing soils only with manure and using legumes”, says Leonard Rusinamhodzi, an agricultural researcher at the Ghana International Institute of Tropical Agriculture.

However, “agroecological principles linked directly to improving soil fertility, such as recycling of mineral and organic elements, crop efficiency and diversity, with for example agroforestry practices and cereal-legume intercropping, remain essential to improve soil health. Soil fertility is based on its organic matter content, provided by plant growth that determines the biomass that is returned to the soil in the form of roots and plant residues. Efficient mineral fertilizer use starts a virtuous circle. These nutrients are crucial for the sustainability of agricultural productivity”, says Gatien Falconnier.

The researchers therefore argue for a nuanced position that recognizes the need to increase mineral fertilizer use in sub-Saharan Africa, in a moderate manner based on efficient practices, in conjunction with the use of agroecological practices and appropriate policy support. This balanced approach is aimed at ensuring long-term food security while preserving ecosystems and preventing soil degradation.

Référence
Falconnier, G. N., Cardinael, R., Corbeels, M., Baudron, F., Chivenge, P., Couëdel, A., Ripoche, A., Affholder, F., Naudin, K., Benaillon, E., Rusinamhodzi, L., Leroux, L., Vanlauwe, B., & Giller, K. E. (2023).

The input reduction principle of agroecology is wrong when it comes to mineral fertilizer use in sub-Saharan Africa. Outlook on Agriculture, 0(0). https://doi.org/10.1177/00307270231199795

*CIRAD, CIMMYT, International Institute of Tropical Agriculture (IITA), Wageningen University and the African Plant Nutrition Institute (APNI)

Contact: presse@cirad.fr

Scientists: 

Gatien Falconnier
gatien.falconnier@cirad.fr

Pauline Chivenge
P.CHIVENGE@apni.net

Leonard Rusinamhodzi
L.Rusinamhodzi@cgiar.org

Exploring alternative solutions: the case for synthetic mulch in a changing world

Written by Julian Bañuelos-Uribe on . Posted in Blogs.

Food security remains elusive for most smallholder farmers reliant on rainfed crop production, given the erratic rainfall patterns induced by climate change in Southern Africa. Among others, conservation agriculture (CA) is a concept often considered to be effective to adapt to these erratic rainfall patterns, enabling farmers to cope better with the prolonged dry spells that are characteristic of the semi-arid regions in Zimbabwe.

Conservation agriculture essentially involves three key pillars, namely, reduced soil disturbance, the use of crop rotations or intercrop associations, and the provision of permanent soil cover. The soil-cover component often requires the use of previous crop residues or other organic materials as a surface mulch. However, local farmers consider this task to be the most laborious aspect of implementing CA, which poses a significant challenge to its widespread uptake.

Collecting insights on influence of synthetic mulch. (Photo: CIMMYT)

Traditionally, farmers are advised to use organic mulch, such as maize residues, for soil cover. However, in most communal areas, there is a growing scarcity of organic mulches as they are predominantly used as livestock feed in mixed crop-livestock farming systems. Ironically, semi-arid regions that benefit from the use of crop residues as soil cover are also regions where the residues are the scarcest due to competing uses as livestock feed or as firewood. These competing interests pose a dilemma, as it is essential to cover the soil while also necessary to feed the animals. In neighboring countries like Malawi, maize residues are also used as fuel for firewood, further increasing the demand. It is clearly important, therefore, to develop alternative solutions to address this pressing issue.

“Since I embarked on my journey in conservation agriculture back in 1998, the matter of residues has been a topic of discussion. It is imperative that we walk the talk and develop practical solutions to meet the needs of farmers who rely on residues to feed their animals. One potential solution we are exploring is the use of synthetic mulches to cover the soil. By employing this method, we can cover the soil, apply fertilizer, and hopefully witness a positive impact. We certainly must develop synthetic materials that can be used sustainably as surface mulches in the semi-arid environments where organics are most scarce yet most needed,” stated Isaiah Nyagumbo, regional cropping systems agronomist.

To test such innovations, some water-conservation experiments were established in Buhera and Mutoko, Zimbabwe, during the last two seasons, and the results have been encouraging.

“I am grateful to work with the CIMMYT team on these water conservation trials, and I hope they continue. Before the trials, we were using organic mulch, but after using the synthetic approach and comparing it with organic mulches and none at all, we are seeing so many positive results. But there are challenges we can’t escape, including affordability. But I have seen higher yield returns this year as I harvested close to 15 by 50kgs of maize,” said Nyawasha, a farmer from Mutoko, Zimbabwe, ward 16.

Further detailed studies to understand these systems have also been established in the current dry season at the CIMMYT campus in Harare, to test the effectiveness of these synthetic mulches under conditions of severe moisture stress. The different treatments include clear synthetic mulch, black synthetic mulch, organic mulch and no mulch. So far, for the maize crop now at flowering stage, the growth and yield are strikingly better in plots under the synthetic mulches compared with the organic and no mulch plots. This clearly shows the importance of finding viable alternatives. The crop with synthetic mulches also developed much faster, all the way from crop emergence.

Exploring the tied-ridging system

In these trials, mulching treatments are being tested in conventionally tilled plots, CA basins (pfumvudza basins) and under the tied-ridging system. Tied ridging has been developed in Zimbabwe for use by smallholder farmers since the 1980s and is well known for its effectiveness in reducing sheet erosion and water run-off. This system employs ridges 15–20 cm high, with crossties in the furrows at 1–2 m intervals that trap rainwater and prevent runoff and soil erosion. However, in a typical rainfed system, poor germination challenges can arise when planting on top of these ridges due to excessive drying of moisture from the raised ridges. Furthermore, during prolonged dry spells, the exposed ridges tend to cause crops to wilt more than flat-planted conventional crops. To address these issues, scientists at CIMMYT in Zimbabwe are also exploring innovative ways to improve the tied-ridging system through ways that minimize water loss through direct soil evaporation.

“This has been one of the shortcomings of the tied-ridging system, and we need ways to overcome this excessive moisture evaporation. Once the water has gone into the soil, it should only leave through plant uptake and not be wasted through direct soil evaporation,” said Nyagumbo.

Integrating synthetic mulch into the tied-ridge system. (Photo: CIMMYT)

One approach being considered is incorporating mulch into the system to reduce evaporation and ensure that captured water is retained. The results are evident in the vibrant greenery of the plants with mulch compared with those without. Observing the number of plants with tassels and silk, it is clear that the plots with clear synthetic material have faster growth and reach maturity sooner compared with the plots with black synthetic mulch.

“My outlook on the use of synthetic mulch on ridges is that they are much more effective, as it makes the soil very loose for good aeration to the plant and encourages high growth rate. I noticed that plants germinated in three days and the little water provided will directly benefit the plant without escaping. I am encouraged to continue doing this tied ridge approach using synthetic material,” said Nyekete, a farmer in Buhera, Zimbabwe, ward 7.

While exploring various options, it has also been important to prioritize and focus on one aspect at a time. The initial focus has been on maize residue, as it is a valuable resource for both soil cover and livestock feed. However, the scarcity of maize residue poses a significant challenge for many farmers, especially in regions like Buhera, Mberengwa and Shurugwi, where animals consume all available resources. Placing maize residues in open fields is not a very viable solution, as freely roaming livestock will just consume it. Fencing or creating structures to protect the residues from livestock also requires substantial effort and resources, thereby making this mulching a daunting task for farmers.

Food for thought

While the challenges faced in providing mulch for conservation agriculture are multifaceted, there is a growing need to develop innovative solutions that address the scarcity of organic mulch and explore alternative methods such as synthetic coverings. By continuously adapting and refining our practices, we can ensure the sustainability of agriculture in this region and improve the livelihoods of farmers.

Fodder Technology Chops Backbreaking Labor in Half for Bangladeshi Women

Written by mcallejas on . Posted in In the media.

Women play a critical role in the future of food security. Female farmers face a significant disadvantage before they ever plow a field or sow a seed. Farming is a challenging profession, and it is even more challenging for women when they perform these functions whilst facing numerous constraints.

Nur-A-Mahajabin Khan, communications officer, showcases how fodder chopper technology is improving the lives of women farmers in rural Bangladesh.

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