funder_partner: Foundation for Food & Agricultural Research (FFAR)

CIMMYT experimental station in Toluca, Mexico. Located in a valley at 2,630 meters above sea level with a cool and humid climate, it is the ideal location for selecting wheat materials resistant to foliar diseases, such as wheat rust. Conventional plant breeding involves selection among hundreds of thousands of plants from crosses over many generations, and requires extensive and costly field, screenhouse and lab facilities. (Photo: Alfonso Cortés/CIMMYT)

Plant breeding innovations

Written by Mike Listman on February 10, 2022. Posted in Explainers.

What is plant breeding?

Emerging in the last 120 years, science-based plant breeding begins by creating novel diversity from which useful new varieties can be identified or formed. The most common approach is making targeted crosses between parents with complementary, desirable traits. This is followed by selection among the resulting plants to obtain improved types that combine desired traits and performance. A less common approach is to expose plant tissues to chemicals or radiation that stimulate random mutations of the type that occur in nature, creating diversity and driving natural selection and evolution.

Determined by farmers and consumer markets, the target traits for plant breeding can include improved grain and fruit yield, resistance to major diseases and pests, better nutritional quality, ease of processing, and tolerance to environmental stresses such as drought, heat, acid soils, flooded fields and infertile soils. Most traits are genetically complex — that is, they are controlled by many genes and gene interactions — so breeders must intercross and select among hundreds of thousands of plants over generations to develop and choose the best.

Plant breeding over the last 100 years has fostered food and nutritional security for expanding populations, adapted crops to changing climates, and helped to alleviate poverty. Together with better farming practices, improved crop varieties can help to reduce environmental degradation and to mitigate climate change from agriculture.

Is plant breeding a modern technique?

Plant breeding began around 10,000 years ago, when humans undertook the domestication of ancestral food crop species. Over the ensuing millennia, farmers selected and re-sowed seed from the best grains, fruits or plants they harvested, genetically modifying the species for human use.

Modern, science-based plant breeding is a focused, systematic and swifter version of that process. It has been applied to all crops, among them maize, wheat, rice, potatoes, beans, cassava and horticulture crops, as well as to fruit trees, sugarcane, oil palm, cotton, farm animals and other species.

With modern breeding, specialists began collecting and preserving crop diversity, including farmer-selected heirloom varieties, improved varieties and the crops’ undomesticated relatives. Today hundreds of thousands of unique samples of diverse crop types, in the form of seeds and cuttings, are meticulously preserved as living catalogs in dozens of publicly-administered “banks.”

The International Maize and Wheat Improvement Center (CIMMYT) manages a germplasm bank containing more than 180,000 unique maize- and wheat-related seed samples, and the Svalbard Global Seed Vault on the Norwegian island of Spitsbergen preserves back-up copies of nearly a million collections from CIMMYT and other banks.

Through genetic analyses or growing seed samples, scientists comb such collections to find useful traits. Data and seed samples from publicly-funded initiatives of this type are shared among breeders and other researchers worldwide. The complete DNA sequences of several food crops, including rice, maize, and wheat, are now available and greatly assist scientists to identify novel, useful diversity.

Much crop breeding is international. From its own breeding programs, CIMMYT sends half a million seed packages each year to some 800 partners, including public research institutions and private companies in 100 countries, for breeding, genetic analyses and other research.

A field worker removes the male flower of a wheat spike, as part of controlled pollination in breeding. (Photo: Alfonso Cortés/CIMMYT)

A century of breeding innovations

Early in the 20th century, plant breeders began to apply the discoveries of Gregor Mendel, a 19th-century mathematician and biologist, regarding genetic variation and heredity. They also began to take advantage of heterosis, commonly known as hybrid vigor, whereby progeny of crosses between genetically different lines will turn out stronger or more productive than their parents.

Modern statistical methods to analyze experimental data have helped breeders to understand differences in the performance of breeding offspring; particularly, how to distinguish genetic variation, which is heritable, from environmental influences on how parental traits are expressed in successive generations of plants.

Since the 1990s, geneticists and breeders have used molecular (DNA-based) markers. These are specific regions of the plant’s genome that are linked to a gene influencing a desired trait. Markers can also be used to obtain a DNA “fingerprint” of a variety, to develop detailed genetic maps and to sequence crop plant genomes. Many applications of molecular markers are used in plant breeding to select progenies of breeding crosses featuring the greatest number of desired traits from their parents.

Plant breeders normally prefer to work with “elite” populations that have already undergone breeding and thus feature high concentrations of useful genes and fewer undesirable ones, but scientists also introduce non-elite diversity into breeding populations to boost their resilience and address threats such as new fungi or viruses that attack crops.

Transgenics are products of one genetic engineering technology, in which a gene from one species is inserted in another. A great advantage of the technology for crop breeding is that it introduces the desired gene alone, in contrast to conventional breeding crosses, where many undesired genes accompany the target gene and can reduce yield or other valuable traits. Transgenics have been used since the 1990s to implant traits such as pest resistance, herbicide tolerance, or improved nutritional value. Transgenic crop varieties are grown on more than 190 million hectares worldwide and have increased harvests, raised farmers’ income and reduced the use of pesticides. Complex regulatory requirements to manage their potential health or environmental risks, as well as consumer concerns about such risks and the fair sharing of benefits, make transgenic crop varieties difficult and expensive to deploy.

Genome editing or gene editing techniques allow precise modification of specific DNA sequences, making it possible to enhance, diminish or turn off the expression of genes and to convert them to more favorable versions. Gene editing is used primarily to produce non-transgenic plants like those that arise through natural mutations. The approach can be used to improve plant traits that are controlled by single or small numbers of genes, such as resistance to diseases and better grain quality or nutrition. Whether and how to regulate gene edited crops is still being defined in many countries.

The mobile seed shop of Victoria Seeds Company provides access to improved maize varieties for farmers in remote villages of Uganda. (Photo: Kipenz Films for CIMMYT)

Selected impacts of maize and wheat breeding

In the early 1990s, a CIMMYT methodology led to improved maize varieties that tolerate moderate drought conditions around flowering time in tropical, rainfed environments, besides featuring other valuable agronomic and resilience traits. By 2015, almost half the maize-producing area in 18 countries of sub-Saharan Africa — a region where the crop provides almost a third of human calories but where 65% of maize lands face at least occasional drought — was sown to varieties from this breeding research, in partnership with the International Institute of Tropical Agriculture (IITA). The estimated yearly benefits are as high as $1 billion.

Intensive breeding for resistance to Maize Lethal Necrosis (MLN), a viral disease that appeared in eastern Africa in 2011 and quickly spread to attack maize crops across the continent, allowed the release by 2017 of 18 MLN-resistant maize hybrids.

Improved wheat varieties developed using breeding lines from CIMMYT or the International Centre for Agricultural Research in the Dry Areas (ICARDA) cover more than 100 million hectares, nearly two-thirds of the area sown to improved wheat worldwide, with benefits in added grain that range from $2.8 to 3.8 billion each year.

Breeding for resistance to devastating crop diseases and pests has saved billions of dollars in crop losses and reduced the use of costly and potentially harmful pesticides. A 2004 study showed that investments since the early 1970s in breeding for resistance in wheat to the fungal disease leaf rust had provided benefits in added grain worth 5.36 billion 1990 US dollars. Global research to control wheat stem rust disease saves wheat farmers the equivalent of at least $1.12 billion each year.

Crosses of wheat with related crops (rye) or even wild grasses — the latter known as wide crosses — have greatly improved the hardiness and productivity of wheat. For example, an estimated one-fifth of the elite wheat breeding lines in CIMMYT international yield trials features genes from Aegilops tauschii, commonly known as “goat grass,” that boost their resilience and provide other valuable traits to protect yield.

Biofortification — breeding to develop nutritionally enriched crops — has resulted in more than 60 maize and wheat varieties whose grain offers improved protein quality or enhanced levels of micro-nutrients such as zinc and provitamin A. Biofortified maize and wheat varieties have benefited smallholder farm families and consumers in more than 20 countries across sub-Saharan Africa, Asia, and Latin America. Consumption of provitamin-A-enhanced maize or sweet potato has been shown to reduce chronic vitamin A deficiencies in children in eastern and southern Africa. In India, farmers have grown a high-yielding sorghum variety with enhanced grain levels of iron and zinc since 2018 and use of iron-biofortified pearl millet has improved nutrition among vulnerable communities.

Innovations in measuring plant responses include remote sensing systems, such as multispectral and thermal cameras flown over breeding fields. In this image of the CIMMYT experimental station in Obregón, Mexico, water-stressed plots are shown in green and red. (Photo: CIMMYT and the Instituto de Agricultura Sostenible)

The future

Crop breeders have been laying the groundwork to pursue genomic selection. This approach takes advantage of low-cost, genome-wide molecular markers to analyze large populations and allow scientists to predict the value of particular breeding lines and crosses to speed gains, especially for improving genetically complex traits.

Speed breeding uses artificially-extended daylength, controlled temperatures, genomic selection, data science, artificial intelligence tools and advanced technology for recording plant information — also called phenotyping — to make breeding faster and more efficient. A CIMMYT speed breeding facility for wheat features a screenhouse with specialized lighting, controlled temperatures and other special fixings that will allow four crop cycles — or generations — to be grown per year, in place of only two cycles with normal field trials. Speed breeding facilities will accelerate the development of productive and robust varieties by crop research programs worldwide.

Data analysis and management. Growing and evaluating hundreds of thousands of plants in diverse trials across multiple sites each season generates enormous volumes of data that breeders must examine, integrate, and co-analyze to inform decisions, especially about which lines to cross and which populations to discard or move forward. New informatics tools such as the Enterprise Breeding System will help scientists to manage, analyze and apply big data from genomics, field and lab studies.

Following the leaders. Driven by competition and the quest for profits, private companies that market seed and other farm products are generally on the cutting edge of breeding innovations. The CGIAR’s Excellence in Breeding (EiB) initiative is helping crop breeding programs that serve farmers in low- and middle-income countries to adopt appropriate best practices from private companies, including molecular marker-based approaches, strategic mechanization, digitization and use of big data to drive decision making. Modern plant breeding begins by ensuring that the new varieties produced are in line with what farmers and consumers want and need.

Cover photo: CIMMYT experimental station in Toluca, Mexico. Located in a valley at 2,630 meters above sea level with a cool and humid climate, it is the ideal location for selecting wheat materials resistant to foliar diseases, such as wheat rust. Conventional plant breeding involves selection among hundreds of thousands of plants from crosses over many generations, and requires extensive and costly field, screenhouse and lab facilities. (Photo: Alfonso Cortés/CIMMYT)

Two women winnowing maize in Rambasti, Kanchanpur, Nepal, back in 2016. Photo: P. Lowe/CIMMYT

New direction in research for advancing gender-responsive maize breeding

Written by Bea Ciordia on February 9, 2022. Posted in Features.

New improved maize varieties may fall short in meeting the needs of women and the poorest of farmers – a concern that remains a focus of the International Maize and Wheat Improvement Center (CIMMYT) and the wider CGIAR.

Lower than expected adoption rates for some new maize varieties suggest that innovative strategies in breeding and seed delivery are likely needed. There is broad recognition of the need to get new germplasm from the CGIAR and its partners into the fields of more farmers in less time.

CIMMYT research on markets and social inclusion focuses on understanding two related dynamics: the unique preferences, needs and circumstances faced by women and the poorest farmers, and the implications these carry for how breeding programs and seed companies design and market new varieties.

Taking stock of knowledge and gaps in gender and maize breeding

A new paper by CIMMYT researchers, “Gender inclusivity through maize breeding in Africa: A review of the issues and options for future engagement”, takes stock of lessons learnt on gender and maize breeding and assesses knowledge gaps that need to be filled to effectively support gender-responsive and gender-intentional breeding and seed systems work.

Decades of research on maize preferences have sought to understand if and how men’s and women’s preferences differ. However, existing data provides unclear guidance to maize breeders on gender-relevant traits to prioritize in product profile design. The evidence suggests a lack of meaningful differences in what men and women are looking for in maize—yield, drought tolerance and early maturity—are high priorities almost across the board.

One reason for the similarity in preferences among women and men may relate to how we evaluate them, the authors argue. Preference studies that focus on evaluation of varieties’ agronomic and productivity-related traits may overlook critical components of farmers’ variety assessment and seed choice, including their household and farming context. Ultimately, they say, we need to explore new approaches to evaluating farmer demand for seed, considering new questions instead of continuing to look for gender-based differences in preferences.

A first step in that direction is to figure out how demand for maize seed differs among farmers according to their needs, priorities and resource limitations. Gender is definitely a part of that equation, but there’s much more to think about, like how maize fits into household food security and livelihoods, decision-making dynamics around maize production, and seed accessibility. New tools will be needed for understanding those and how decision-making around seed happens in real-world contexts.

Understanding how farmers make decisions on seed choice

The authors offer several practical suggestions for maize breeders and other researchers in this space:

First, explore tools that allow farmers to evaluate varieties in their household context. Large-scale farmer-managed on-farm trials have gained attention in the CGIAR as tools for more accurate assessment of farmer preferences. These approaches have several added advantages. They enable evaluation of variety performance under realistic management conditions—including under management practices used disproportionately by women, such as intercropping, which is typically excluded from larger researcher-managed trials. These approaches also enable farmer evaluation of maize varieties not only in terms of in-field performance and yield at harvest stage, but in terms of grain quality after harvest. This is particularly important for social inclusion, given women’s disproportionate attention to traits related to processing and consumption.
Second, move beyond gender-based preferences in evaluating seed demand. Gendered preferences matter, but they may not be the sole factor that determines a farmer’s choice of seed. We need to understand market segments for seed in relation to farmers’ aspirations, risk perceptions and tolerance, livelihood priorities, and household context. This also means exploring the intrahousehold gender dynamics of maize farming and seed choice to understand women’s roles in decision-making in maize production, processing, and consumption.
Finally, consider questions related to maize seed systems more broadly. Are maize seed systems capable of delivering gender-responsive and gender-intentional varieties to women and men? What are the barriers to wider uptake of new varieties aside from variety suitability? Innovative marketing and delivery mechanisms may be critical to realizing gains from more gender-intentional breeding.

With the transition to the One CGIAR, sharing tools and lessons learned across crops will be increasingly important. Researchers in the CGIAR community have developed new tools for gender-responsive and gender-intentional breeding. This includes through the Gender and Breeding Initiative, which has published the G+ tools to support gendered market segmentation and gender-intentional product profile development.

While learning from one another’s experiences will prove essential during the transition, recognizing that the gender dynamics of maize production may be very different from sweet potato production will also be key. Here, the new Market Intelligence & Product Profiles initiative and SeEdQUAL initiative on seed systems will both create new spaces for exploring these issues across crops.

CGIAR Gender & Breeding Initiative link: http://www.rtb.cgiar.org/gender-breeding-initiative/

Breeding for better gender equity at CGIAR Excellence in Breeding: https://excellenceinbreeding.org/blog/breeding-better-gender-equity

A farmer harvests wheat in one of CIMMYT's research plots in Ethiopia. (Photo: P. Lowe/CIMMYT)

International scientists awarded grants supporting the HeDWIC-FFAR project to boost climate resilience in wheat

Written by Alison Doody on February 2, 2022. Posted in News.

Five international wheat research teams have been awarded grants for their proposals to boost climate resilience in wheat through discovery and development of new breeding technologies, screening tools and novel traits.

Wheat is one of the world’s most important staple crops, accounting for about 20% of all human calories and protein and is increasingly threatened by the impacts of climate change. Experts around the world are working on ways to strengthen the crop in the face of increasing heat and drought conditions.

The proposals were submitted in response to a call by the Heat and Drought Wheat Improvement Consortium (HeDWIC), led by the International Maize and Wheat Improvement Center (CIMMYT) and global partners, made in 2021.

The grants were made possible by co-funding from the Foundation for Food & Agriculture Research (FFAR) and in-kind contributions from awardees as part of a project which brings together the latest research from scientists across the globe to deliver climate resilient wheat to farmers as quickly as possible.

Cutting-edge wheat research

Owen Atkin, from the Centre for Entrepreneurial Agri-Technology at the Australian National University, leads the awarded project “Discovering thermally stable wheat through exploration of leaf respiration in combination with photosystem II capacity and heat tolerance.”

“The ratio of dark respiration to light and CO2 saturated photosynthesis is a clear indicator of the respiratory efficiency of a plant,” Atkin said. “We will measure and couple this indicator of respiratory efficiency to the leaf hyperspectral signature of field grown wheat exposed to heat and drought. The outcome could be a powerful tool which is capable of screening for wheat lines that are more productive when challenged with drought and heatwave.”

Hannah M. Schneider, of Wageningen University & Research, leads the awarded project examining the use of a novel root trait called Multiseriate Cortical Sclerenchyma to increase drought-tolerance in wheat.

“Drought is a primary limitation to global crop production worldwide. The presence of small outer cortical cells with thick, lignified cell walls (MCS: Multiseriate Cortical Sclerenchyma) is a novel root trait that has utility in drought environments,” Schneider said. “The overall objective of this project is to evaluate and develop this trait as a tool to improve drought resistance in wheat and in other crops.”

An improved wheat variety grows in the field in Islamabad, Pakistan. (Photo: A. Yaqub/CIMMYT)

John Foulkes, of the University of Nottingham, leads an awarded project titled “Identifying spike hormone traits and molecular markers for improved heat and drought tolerance in wheat.”

“The project aims to boost climate-resilience of grain set in wheat by identifying hormone signals to the spike that buffer grain set against extreme weather, with a focus on cytokinin, ABA and ethylene responses,” Foulkes said. “This will provide novel phenotyping screens and germplasm to breeders, and lay the ground-work for genetic analysis and marker development.”

Erik Murchie, from the University of Nottingham, leads an awarded project to explore new ways of determining genetic variation in heat-induced growth inhibition in wheat.

“High temperature events as part of climate change increasingly limit crop growth and yield by disrupting metabolic and developmental processes. This project will develop rapid methods for screening growth and physiological processes during heat waves, generating new genetic resources for wheat,” Murchie said.

Eric Ober of the National Institute of Agricultural Botany in the UK, leads the awarded project “Targeted selection for thermotolerant isoforms of starch synthase.”

“Wheat remains a predominant source of calories and is fundamental to regional food security around the world. It is urgent that breeders are equipped to produce new varieties with increased tolerance to heat and drought, two stresses that commonly occur together, limiting grain production. The formation and filling of grain depends on the synthesis of starch, but a key enzyme in the pathway, starch synthase, is particularly sensitive to temperatures over 25°C. However, there exist forms of this enzyme that exhibit greater thermotolerance than that found in most current wheat varieties,” Ober said. “This project aims to develop a simple assay to screen diverse germplasm for sources of more heat-resistant forms of starch synthase that could be bred into new wheat varieties in the future.”

Breakthroughs from these projects are expected to benefit other crops, not just wheat. Other benefits of the projects include closer interaction between scientists and breeders and capacity building of younger scientists.

How does CIMMYT’s improved maize get to the farmer?

New CIMMYT maize hybrids available from Eastern Africa Breeding Program

Written by Rodrigo Ordóñez on January 27, 2022. Posted in News.

The International Maize and Wheat Improvement Center (CIMMYT) is offering a new set of elite, improved maize hybrids to partners for commercialization in eastern Africa and similar agro-ecological zones. National agricultural research systems (NARS) and seed companies are invited to apply for licenses to register and commercialize these new hybrids, in order to bring the benefits of the improved seed to farming communities.

The deadline to submit applications to be considered during the first round of allocations is February 11, 2022. Applications received after that deadline will be considered during the following round of product allocations.

Information about the newly available CIMMYT maize hybrids from the Latin America breeding program, application instructions and other relevant material is available in the CIMMYT Maize Product Catalog and in the links provided below.

Product Profile	Newly available CIMMYT hybrids	*Basic traits*	*Nice-to-have / Emerging traits*
Eastern Africa Product Profile 1A (EA-PP1A)	CIM20EAPP1-01-38	Intermediate-maturing, white, high yielding, drought tolerant, NUE, and resistant to GLS, TLB, Ear rots, and MSV	MLN, Striga, FAW
	CIM20EAPP1-01-1
	CIM20EAPP1-01-16

You can download the full text and trial data summary for the CIMMYT Eastern Africa Maize Regional On-Station (Stage 4) and On-Farm (Stage 5) Trials: Results of the 2020 to 2021 Seasons and Product Announcement.

Applications must be accompanied by a proposed commercialization plan for each product being requested. Applications may be submitted online via the CIMMYT Maize Licensing Portal and will be reviewed in accordance with CIMMYT’s Principles and Procedures for Acquisition and use of CIMMYT maize hybrids and OPVs for commercialization. Specific questions or issues faced with regard to the application process may be addressed to GMP-CIMMYT@cgiar.org with attention to Nicholas Davis, Program Manager, Global Maize Program, CIMMYT.

APPLY FOR A LICENSE

Wheat fields at CIMMYT's experimental stations near Ciudad Obregón, Sonora state, Mexico. (Photo: M. Ellis/CIMMYT)

Scientists bridge theory and practice to boost climate resilience in wheat

Written by Alison Doody on October 11, 2021. Posted in Features.

With the past decade identified as the warmest on record and global temperatures predicted to rise by as much as 2 degrees Celsius over preindustrial levels by 2050, the world’s staple food crops are increasingly under threat.

A new review published this month in the Journal of Experimental Botany describes how researchers from the International Maize and Wheat Improvement Center (CIMMYT) and collaborators are boosting climate resilience in wheat using powerful remote sensing tools, genomics and big data analysis. Scientists are combining multiple approaches to explore untapped diversity among wheat genetic resources and help select better parents and progeny in breeding.

The review — authored by a team of 25 scientists from CIMMYT, Henan Agricultural University, the University of Adelaide and the Wheat Initiative — also outlines how this research can be harnessed on a global level to further accelerate climate resilience in staple crops.

“An advantage of understanding abiotic stress at the level of plant physiology is that many of the same tools and methods can be applied across a range of crops that face similar problems,” said first author and CIMMYT wheat physiologist Matthew Reynolds.

Abiotic stresses such as temperature extremes and drought can have devastating impacts on plant growth and yields, posing a massive risk to food security.

Harnessing research across a global wheat improvement network for climate resilience: research gaps, interactive goals, and outcomes.

Addressing research gaps

The authors identified nine key research gaps in efforts to boost climate resilience in wheat, including limited genetic diversity for climate resilience, a need for smarter strategies for stacking traits and addressing the bottleneck between basic plant research and its application in breeding.

Based on a combination of the latest research advances and tried-and-tested breeding methods, the scientists are developing strategies to address these gaps. These include:

Using big data analysis to better understand stress profiles in target environments and design wheat lines with appropriate heat and drought adaptive traits.
Exploring wheat genetic resources for discovery of novel traits and genes and their use in breeding.
Accelerating genetic gains through selection techniques that combine phenomics with genomics.
Crowd-sourcing new ideas and technologies from academia and testing them in real-life breeding situations.

These strategies will be thoroughly tested at the Heat and Drought Wheat Improvement Network (HeDWIC) Hub under realistic breeding conditions and then disseminated to other wheat breeding programs around the world facing similar challenges.

One factor that strongly influences the success and acceleration of climate resilience technologies, according to Reynolds, is the gap between theoretical discovery research and crop improvement in the field.

“Many great ideas on how to improve climate-resilience of crops pile up in the literature, but often remain ‘on the shelf’ because the research space between theory and practice falls between the radar of academia on the one hand, and that of plant breeders on the other,” Reynolds explained.

Translational research — efforts to convert basic research knowledge about plants into practical applications in crop improvement — represents a necessary link between the world of fundamental discovery and farmers’ fields and aims to bridge this gap.

Main research steps involved in translating promising technologies into genetic gains (graphical abstract, adapted from Reynolds and Langridge, 2016). Reprinted under licence CC BY-NC-ND.

The impacts of this research, conducted under HeDWIC — a project led by CIMMYT in partnership with experts around the world — will be validated on a global scale through the International Wheat Improvement Network (IWIN), with the potential to reach at least half of the world’s wheat-growing area.

The results will benefit breeders and researchers but, most importantly, farmers and consumers around the world who rely on wheat for their livelihoods and their diets. Wheat accounts for about 20% of all human calories and protein, making it a pillar of food security. For about 1.5 billion resource-poor people, wheat is their main daily staple food.

With the world population projected to rise to almost ten billion by 2050, demand for food is predicted to increase with it. This is especially so for wheat, being a versatile crop both in terms of where it can grow and its many culinary and industrial uses. However, current wheat yield gains will not meet 2050 demand unless serious action is taken. Translational research and strategic breeding are crucial elements in ensuring that research is translated into higher and stable yields to meet these challenges.

Read the full study:
Harnessing translational research in wheat for climate resilience

Cover photo: Wheat fields at CIMMYT’s experimental stations near Ciudad Obregón, Sonora state, Mexico. (Photo: M. Ellis/CIMMYT)

Gyanendra Pratap Singh (center), Director of ICAR-IIWBR, presents at the 60th All India Wheat and Barley Research Workers’ Meet. (Photo: Courtesy of ICAR-IIWBR)

CIMMYT scientists join 60^th All India Wheat and Barley Research Workers’ Meet

Written by Madeline Dahm on September 10, 2021. Posted in News.

The International Maize and Wheat Improvement Center’s (CIMMYT) legacy of work with the Indian Centre for Agricultural Research (ICAR) has once again produced more successful collaborations this year. This solid partnership resulted in the release of new varieties poised to bring new, superior yielding, disease-resistant, high-quality wheat varieties suitable for different production environments to Indian farms.

The National Variety Release Committee announced the release of nine new varieties at the 60^th All India Wheat and Barley Research Workers’ Virtual Meet on August 23–24, 2021, hosted by the Indian Institute of Wheat and Barley Research (IIWBR) of ICAR. Of the nine new varieties identified, five were selected by national partners from CIMMYT international trials and nurseries.

At the event, ICAR-IIWBR director Gyanendra Pratap (GP) Singh highlighted the impressive growth trajectory of India’s wheat production, estimated at 109.52 million tons of wheat harvested in 2021, a figure which was 86.53 million tons in 2015 and less than 60 million tons in 1991. Singh highlighted that this success is dependent upon the deployment of superior wheat varieties, bridging yield and information gaps, strengthened seed value chain, supportive government policies and, of course, farmer support to adopt new varieties and technologies.

The CIMMYT-derived varieties announced at the meeting include DBW296, DBW327, DBW332, HUW296 and JKW261. A few days earlier, variety PBW869 was released by the Punjab Agricultural University for growing in Punjab State under conservation agriculture practices.

“An innovative and powerful feature of ICAR-CIMMYT collaboration has been the introduction of long-term (10-month) rotational involvement of Indian young scientists in CIMMYTs breeding program at Mexico as well as in wheat blast screening in Bolivia,” said Arun Joshi, CIMMYT Regional Representative for Asia and Managing Director, Borlaug Institute for South Asia (BISA). “In this way, the breeding program of CIMMYT is an excellent example of joint breeding program with national institutions.”

At the 60th All India Wheat and Barley Research Workers’ Meet, participants highlighted new varieties, production growth and strengthened collaboration. (Photo: CIMMYT)

Beyond expectations

In addition to these important new wheat varieties, some CIMMYT-derived wheat varieties that were released in recent years have now been deemed suitable for regions beyond their initial region of cultivation, showing wide adaptation and yield stability.

Wheat variety DBW222, released in 2020 for the northwestern plain zone, has now been deemed suitable for cultivation in the northeastern plain zone. Similarly, DBW187, which was initially released for the northeastern plain zone, and then for northwestern plain zone as well for early sowing, is now also extended for sowing in the central zone, together representing 25 million hectares of the 31 million hectares of wheat grown in India.

“Farmers prefer these types of varieties that give them flexibility during sowing time, and have high, stable yields, and disease resistance,” GP Singh said at the meeting.

A major achievement discussed at this year’s event was that three of the new varieties — DBW187, DBW303 and DBW222 — achieved record-high demand in Breeders Seed Indent, with first, second and seventh ranks, respectively. This is a reflection and indirect measure of popularity and demand for a variety. IIWBR’s innovative strategy to implement pre-release seed multiplication and create demand for seeds from new varieties has led to a faster turnover of improved varieties.

According to Ravi Singh, Distinguished Scientist and Head of Global Wheat Improvement at CIMMYT, the collaborators are “further expanding our partnership through the support from the Accelerating Genetic Gains in Maize and Wheat (AGG) and zinc-mainstreaming projects, to expand testing of larger sets of elite lines in targeted populations of environments of the four South Asian countries where various IIBWR-affiliated institutions shall expand testing in the 2021–22 crop season.” CIMMYT looks forward to continuing ongoing and new collaborations with the ICAR-IIWBR programs to deliver even faster genetic gain for yield and grain zinc levels in new varieties, he explained.

Speaking during the meeting Alison Bentley, Director of CIMMYT’s Global Wheat Program, highlighted the collaborative efforts underway as part of the AGG project to accelerate breeding progress. “Innovations and discoveries in breeding approaches are being rapidly made — with further investment needed — to quickly and equitably accumulate and deploy them to farmers,” she said.

Wheat leaves showing symptoms of heat stress. (Photo: CIMMYT) For more information, see CIMMYT's Wheat Doctor: http://wheatdoctor.cimmyt.org/index.php?option=com_content&task=view&id=84&Itemid=43&lang=en. Photo credit: CIMMYT.

Seed giants must collaborate or be dwarfed by threat of climate change

Written by Rodrigo Ordóñez on August 16, 2021. Posted in Blogs.

The COVID-19 pandemic has exposed vast inequalities when it comes to food security. But there is an even larger and more concerning crisis waiting for us: global food shortages caused by climate change.

According to the latest report from the Intergovernmental Panel on Climate Change, total global warming is likely to rise around 1.5 degrees Celsius within the next two decades.

Nobody knows when or how hard it will hit, but we inch closer each year with new temperature records, the spread of pests, and emerging crop diseases. We are already seeing the beginning of this future crisis. Climate-induced food price hikes have caused political turmoil in the Middle East, while climate-related disasters have been linked with mass human migration in South Asia.

Every seed company and crop research center worldwide is preoccupied with the race to breed hardier crops to keep pace with the demands of a growing population as circumstances become increasingly challenging. But the truth is, this is a relay race, and yet the crop research field is running 100-meter sprints in different places at different times.

For every scientific advance, other areas of crop research go under-resourced and are technology poor, with asymmetries in research investment creating islands of knowledge that are disparate and disconnected. These research asymmetries hold back crop improvement as a whole, contributing to climate-induced crop failure and the political turmoil that ensues when staple foods become scarce.

While it is common for academic crop scientists to share ideas and collaborate with industry, it is far less typical for major seed companies to cooperate with each other.

If the public and private sectors are to have any chance of outrunning climate change, industry must shift toward investing in mutually beneficial research and development to pool resources and build on every gain, in the interests of the whole.

In an unprecedented first step that reveals just how much pressure the sector feels about the daunting task ahead, some of the crop industry’s main players and competitors — including Syngenta, BASF, Corteva and KWS — recently shared their insights into the gaps in existing crop science.

The shortcomings identified that hold back the crop industry from addressing the looming food crisis have three features in common. They are all under-represented in scientific literature, are likely to boost productivity across a wide range of crops and environments, and crucially, the research is fundamental enough to be “pre-competitive,” or valuable without jeopardizing individual business outcomes.

For example, although scientists have made progress towards improving the potential of crucial processes in crop development, like photosynthesis, other gaps in knowledge must be filled to ensure that this translates into improved yield, especially under unstable environments.

Such research is critical to ensuring reliable harvests across a range of crops, and can be conducted without infringing the intellectual property or proprietary technology of any single company.

However, accessing research funding can be surprisingly difficult. Public research budgets are shrinking, their funds are at risk of being re-appropriated, and collaboration is not the industry standard.

New funding models, such as public-private partnerships, can collectively address knowledge gaps to avoid potential catastrophes for society at large.

This approach has already proven fruitful. The public-private consortium “Crops of the Future Collaborative” brings competitors together to jointly fund research into the characteristics crops need to adapt to a changing future.

Industry matched the Collaborative’s initial $10 million investment by the Foundation for Food & Agriculture Research to work on corn that survives in drought conditions and leafy greens that are resistant to pests.

Conducting this research jointly drastically improves crop efficiency and the technological toolbox available to breeders and other crop scientists, passing the baton in the race towards a food secure future.

Increasing the global food supply through research and development is the most achievable and sure approach to avoid a global food crisis, and comes with historically high returns on investment. Furthermore, scientists can tap into a global infrastructure of researchers across public and private sectors, international organizations, and the millions of farmers worldwide who have willingly collaborated over the last half century to provide enough food for all.

Failure to collaborate will ultimately result in unsustainable food systems, which not only renders seed companies obsolete but threatens a prerequisite of civilization: food security.

The private sector has the knowledge and resources to redefine the race. Rather than competing against one another, the crop industry must join forces to compete instead with climate change. And it is a contest we can only win if all players work together.

This op-ed was originally published on the Des Moines Register.

Matthew Reynolds is a distinguished scientist with the International Maize and Wheat Improvement Center. Jeffrey L. Rosichan is a director with Foundation for Food & Agriculture Research. Leon Broers is a board member with KWS SAAT SE & Co. KGaA.

Florence Ochieng harvests green maize on her 105-acre family farm near Kitale, Kenya. (Photo: P. Lowe/CIMMYT)

When it comes to maize variety choices, can farmers have it all?

Written by Emma Orchardson on August 13, 2021. Posted in News.

Smallholder farmers are often torn between maize seed varieties that have multiple desirable traits. Since they cannot always have it all — there are limits on what traits breeders can integrate in any given variety — they face the dilemma of which seed to pick at the expense of an equally desirable option.

Trait preference trade-offs among maize farmers in western Kenya, published in March 2021, provides evidence of this prioritization and seeks to help breeders, seed companies and other stakeholders set priorities that account for farmers’ needs and their willingness to make preference trade-offs. The researchers evaluated responses from 1,288 male and female farmers in the mid-altitude maize growing areas of western Kenya.

The study argues that farmer-centered seed systems (including seed companies) should be guided by farmers’ priorities and reflect a greater understanding of the tradeoffs these farmers make between traits and varieties. They have two key options, according to Paswel Marenya, the study’s lead researcher and adoption and impact assessment economist at the International Maize and Wheat Improvement Center (CIMMYT). The first involves prioritizing the critical must-have traits in any one variety. The second option entails having multiple varieties that meet diverse farmers’ needs and then segmenting the seed markets.

While Marenya argues that prioritization is important for balancing commercial realities and farmers’ diverse interests, he is quick to add that “market segmentation has limits imposed by the commercial viability of each segment.”

“At every turn, from breeding to farmer varietal preferences to seed company considerations, there have to be trade-offs, as one cannot keep segmenting the market forever,” Marenya said. “At some point, you must stop and choose what traits to prioritize in your breeding or commercially viable market segments, based on the most pressing challenges already identified.”

CIMMYT researchers conduct interviews in Kenya to determine farmer preferences for maize traits. (Photo: CIMMYT)

Differences in tradeoffs among men and women

From a gender lens, the paper reveals an obvious difference in tradeoffs made by men and women. Whereas the two groups desire some similar traits in their varieties of choice, women seem to be willing to make slightly larger yield sacrifices in favor of tolerance to drought and Striga and good storability. Women also valued good storability over 90-day maturity, while men appeared to place a higher value on the closed tip, a sign of resistance to moisture infiltration which causes grain rotting.

“These results imply that unless the risks of storage or pre-harvest losses are reduced or eliminated, the value of high yielding varieties can be diminished if they are susceptible to production stresses or the grain characteristics make them susceptible to storage pests,” the study states.

The study indicates that farmers may adopt stress tolerant and high yielding varieties with somewhat low storability only if advanced grain storage technologies are available.

Until then, the suggestion to policy makers responsible for maize breeding is to use “multi-criteria evaluations” of new varieties to ensure that traits for stress tolerance and storability are given optimal weighting in variety release decisions.

Additionally, information about farmer preferences should be fed back to breeding programs in national and international institutes responsible for maize genetic improvement.

A view from above

Written by Alison Doody on May 25, 2021. Posted in Features.

Scientists at the International Maize and Wheat Improvement Center (CIMMYT) have been harnessing the power of drones and other remote sensing tools to accelerate crop improvement, monitor harmful crop pests and diseases, and automate the detection of land boundaries for farmers.

A crucial step in crop improvement is phenotyping, which traditionally involves breeders walking through plots and visually assessing each plant for desired traits. However, ground-based measurements can be time-consuming and labor-intensive.

This is where remote sensing comes in. By analyzing imagery taken using tools like drones, scientists can quickly and accurately assess small crop plots from large trials, making crop improvement more scalable and cost-effective. These plant traits assessed at plot trials can also be scaled out to farmers’ fields using satellite imagery data and integrated into decision support systems for scientists, farmers and decision-makers.

Here are some of the latest developments from our team of remote sensing experts.

An aerial view of the Global Wheat Program experimental station in Ciudad Obregón, Sonora, Mexico (Photo: Francisco Pinto/CIMMYT)

Measuring plant height with high-powered drones

A recent study, published in Frontiers in Plant Science validated the use of drones to estimate the plant height of wheat crops at different growth stages.

The research team, which included scientists from CIMMYT, the Federal University of Viçosa and KWS Momont Recherche, measured and compared wheat crops at four growth stages using ground-based measurements and drone-based estimates.

The team found that plant height estimates from drones were similar in accuracy to measurements made from the ground. They also found that by using drones with real-time kinematic (RTK) systems onboard, users could eliminate the need for ground control points, increasing the drones’ mapping capability.

Recent work on maize has shown that drone-based plant height assessment is also accurate enough to be used in maize improvement and results are expected to be published next year.

A map shows drone-based plant height estimates from a maize line trial in Muzarabani, Zimbabwe. (Graphic: CIMMYT)

Advancing assessment of pests and diseases

CIMMYT scientists and their research partners have advanced the assessment of Tar Spot Complex — a major maize disease found in Central and South America — and Maize Streak Virus (MSV) disease, found in sub-Saharan Africa, using drone-based imaging approach. By analyzing drone imagery, scientists can make more objective disease severity assessments and accelerate the development of improved, disease-resistant maize varieties. Digital imaging has also shown great potential for evaluating damage to maize cobs by fall armyworm.

Scientists have had similar success with other common foliar wheat diseases, Septoria and Spot Blotch with remote sensing experiments undertaken at experimental stations across Mexico. The results of these experiments will be published later this year. Meanwhile, in collaboration with the Federal University of Technology, based in Parana, Brazil, CIMMYT scientists have been testing deep learning algorithms — computer algorithms that adjust to, or “learn” from new data and perform better over time — to automate the assessment of leaf disease severity. While still in the experimental stages, the technology is showing promising results so far.

CIMMYT researcher Gerald Blasch and EIAR research partners Tamrat Negash, Girma Mamo and Tadesse Anberbir (right to left) conduct field work in Ethiopia. (Photo: Tadesse Anberbir)

Improving forecasts for crop disease early warning systems

CIMMYT scientists, in collaboration with Université catholique de Louvain (UCLouvain), Cambridge University and the Ethiopian Institute of Agricultural Research (EIAR), are currently exploring remote sensing solutions to improve forecast models used in early warning systems for wheat rusts. Wheat rusts are fungal diseases that can destroy healthy wheat plants in just a few weeks, causing devastating losses to farmers.

Early detection is crucial to combatting disease epidemics and CIMMYT researchers and partners have been working to develop a world-leading wheat rust forecasting service for a national early warning system in Ethiopia. The forecasting service predicts the potential occurrence of the airborne disease and the environmental suitability for the disease, however the susceptibility of the host plant to the disease is currently not provided.

CIMMYT remote sensing experts are now testing the use of drones and high-resolution satellite imagery to detect wheat rusts and monitor the progression of the disease in both controlled field trial experiments and in farmers’ fields. The researchers have collaborated with the expert remote sensing lab at UCLouvain, Belgium, to explore the capability of using European Space Agency satellite data for mapping crop type distributions in Ethiopia. The results will be also published later this year.

CIMMYT and EIAR scientists collect field data in Asella, Ethiopia, using an unmanned aerial vehicle (UAV) data acquisition. (Photo: Matt Heaton)

Delivering expert irrigation and sowing advice to farmers phones

Through an initiative funded by the UK Space Agency, CIMMYT scientists and partners have integrated crop models with satellite and in-situ field data to deliver valuable irrigation scheduling information and optimum sowing dates direct to farmers in northern Mexico through a smartphone app called COMPASS — already available to iOS and Android systems. The app also allows farmers to record their own crop management activities and check their fields with weekly NDVI images.

The project has now ended, with the team delivering a webinar to farmers last October to demonstrate the app and its features. Another webinar is planned for October 2021, aiming to engage wheat and maize farmers based in the Yaqui Valley in Mexico.

CIMMYT researcher Francelino Rodrigues collects field data in Malawi using a UAV. (Photo: Francelino Rodrigues/CIMMYT)

Detecting field boundaries using high-resolution satellite imagery

In Bangladesh, CIMMYT scientists have collaborated with the University of Buffalo, USA, to explore how high-resolution satellite imagery can be used to automatically create field boundaries.

Many low and middle-income countries around the world don’t have an official land administration or cadastre system. This makes it difficult for farmers to obtain affordable credit to buy farm supplies because they have no land titles to use as collateral. Another issue is that without knowing the exact size of their fields, farmers may not be applying to the right amount of fertilizer to their land.

Using state of the art machine learning algorithms, researchers from CIMMYT and the University of Buffalo were able to detect the boundaries of agricultural fields based on high-resolution satellite images. The study, published last year, was conducted in the delta region of Bangladesh where the average field size is only about 0.1 hectare.

A CIMMYT scientist conducts an aerial phenotyping exercise in the Global Wheat Program experimental station in Ciudad Obregón, Sonora, Mexico. (Photo: Francisco Pinto/CIMMYT)

Developing climate-resilient wheat

CIMMYT’s wheat physiology team has been evaluating, validating and implementing remote sensing platforms for high-throughput phenotyping of physiological traits ranging from canopy temperature to chlorophyll content (a plant’s greenness) for over a decade. Put simply, high-throughput phenotyping involves phenotyping a large number of genotypes or plots quickly and accurately.

Recently, the team has engaged in the Heat and Drought Wheat Improvement Consortium (HeDWIC) to implement new high-throughput phenotyping approaches that can assist in the identification and evaluation of new adaptive traits in wheat for heat and drought.

The team has also been collaborating with the Accelerating Genetic Gains in Maize and Wheat (AGG) project, providing remote sensing data to improve genomic selection models.

Cover photo: An unmanned aerial vehicle (UAV drone) in flight over CIMMYT’s experimental research station in Ciudad Obregon, Mexico. (Photo: Alfredo Saenz/CIMMYT)

Pauline Muindi, gender research associate with CIMMYT, at the mock agrodealer shop where she acted as a clerk. (Photo: CIMMYT)

Buying into new seed

Written by Rodrigo Ordóñez on May 24, 2021. Posted in Features.

Mary Nzau enters a mock agrodealer shop set up on a field on the outskirts of Tala town in Machakos County, Kenya. On display are nine 2kg bags of hybrid maize seed. She picks one. By the look of it, her mind is made up. After a quick scan of the shelf, she has in her hand the variety that she has been purchasing for years.

Regina Mbaika Mutua is less lucky. The variety she always buys is not on display in the mock shop. As part of the experiment, the research team has removed from the shelf the variety she indicated she usually buys. The team’s goal is to observe what factors influence her seed purchase decision in the absence of the variety she was expecting to purchase.

“Although I did not find the variety I was looking for, I picked an alternative as I have seen it perform well on a neighboring farm,” Mutua says, adding that she will plant it this season alongside recycled (farm-saved) seed on her one-acre farm.

Michael Mutua passes up the popular variety he has been planting for the previous two years. He picks one that has been advertised extensively on local radio. “I have heard about it severally on radio. I would like to experiment with this new seed and see how it performs on my farm. Should I like the results, I will give it a chance in ensuing seasons,” he says.

Pieter Rutsaert explains the study setup at a mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)

The big adoption conundrum

The goal of the out-of-stock study is to improve an understanding of how farmers make their maize seed choices, says Pieter Rutsaert, Markets and Value Chain Specialist at the International Maize and Wheat Improvement Center (CIMMYT).

“We do this by inviting farmers to a mock agrodealer store that we set up in their villages and give them a small budget to purchase a bag of seed. However, not all farmers walk into the same store: some will find their preferred variety, others won’t. Some will have access to additional trait information or see some varieties with price promotions while others don’t.”

Rutsaert acknowledges that breeding programs and their partner seed companies have done a great job at giving farmers access to maize hybrids with priority traits such as drought tolerance and high yield. CIMMYT then works closely with local seed companies to get varieties into the hands of farmers. “We want to extend that support by providing insights to companies and public breeding programs on how to get new varieties more quickly into the hands of farmers,” he says.

Pauline Muindi (left), gender research associate with CIMMYT, acts as a mock agrodealer clerk and attends a farmer. (Photo: CIMMYT)

The hybrid maize seed sector in Kenya is highly competitive. Amid intensifying competition, new varieties face a daunting task breaking into the market, independent of their quality. While farmers now have more options to pick from, a major challenge has been how to get them to adopt new varieties.

“Moving farmers from something they know to something they don’t is not easy. They tend to stick with what they know and have been growing for years,” Rutsaert says.

Pauline Muindi, gender research associate with CIMMYT, acted as the stand-in clerk at the mock store. She noticed that farmers tend to spend very little time in the shop when their preferred variety is available. However, this all changes in the out-of-stock situation, pushing farmers to step out of their comfort zone and explore new options.

The first step to overcoming this challenge is to entice maize farmers to try a new seed variety, even just once, Rutsaert observes. If it is a good variety, farmers will see that and then the market will work in its favor: farmers will come back to that variety in subsequent years and tell others about it.

“The good news is that many of the varieties we are currently seeing on the market have performed well — that’s why they’re popular. But there are newer varieties that are even better, especially in terms of attributes like drought tolerance. We would like to understand how farmers can be convinced to try out these newer varieties. Is it about the need for more awareness on varietal traits? Can we use price promotions? Or are there other factors?” he says.

A researcher interviews Mary Nzau (right), a farmer from Tala town in Machakos County, after her mock purchase. (Photo: Joshua Masinde/CIMMYT)

Does seed price matter?

“With today’s climate uncertainty, it is better to stick to a variety that is adapted to such climate rather than banking on a variety one is oblivious of. The risk is not worth it,” Nzau says. She adds that she would rather buy a higher-priced seed packet she knows and trusts than a lower-priced one that she has not used in the past. Radio promotions of new or other varieties have limited sway over her decision to make the switch.

Faith Voni, another farmer, agrees. “It is better to purchase a higher-priced variety whose quality I can vouch for than risk purchasing a lower-priced one that I know little about. I do not wish to take such a risk.” Voni says she would also be more inclined to experiment with another variety that she had seen perform well on a neighbor’s farm.

Michael Mutua holds a different view. “If there is an option of an equally good but new variety that is lower-priced than the variety I prefer, my wallet decides,” he says.

Vivian Hoffmann, an economist at the International Food Policy Research Institute (IFPRI) and collaborator on the study, says price can be key for convincing consumers to try a new product. “Our previous research on maize flour choice found that a provisional 10 percent discount boosted sales tremendously,” Hoffmann says. “Of course, that only gets your foot in the door; after that, a new variety will need to win farmers over based on its merits.”

Hoffmann is interested in the extent to which drawing farmers’ attention to key varietal attributes influences their seed choice. “This information is generally already available on seed packets, but we live in a world of information overload. Promoting certain attributes through in-store signage is an approach that is widely used to help consumers make more healthier food choices. Doing the same for new seed varieties makes a lot of sense.”

Michael Mutua (left) responds to preliminary questions from one of the research team members before proceeding to make his seed selection at the mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)

The value of drought tolerance

Situated on Kenya’s eastern region, Machakos is characterized by persistent water stress. Climate change induced erratic rainfall has pushed traits that can tolerate the unfavorable weather conditions in the favorite’s corner. While other traits such as high yield and disease resistance are equally important, the seed, when planted, must first withstand the effects of droughts or water stress in some seasons and germinate. This is the most crucial step in the long journey to either a decent, bare minimum or no yield. A lot of farmers still plant recycled seed alongside hybrid varieties. But these are no match to water stress conditions, which decimate fields planted with farmer-saved seed.

“If a variety is not climate resilient, I will likely not harvest anything at all,” says Nzau. She has planted a drought-tolerant variety for ten years now. Prior to that, she had planted about three other varieties as well as recycled seed. “The only advantage with recycled seed is that given the right amount of rainfall, they mature fast — typically within two months. This provides my family with an opportunity to eat boiled or roast maize,” she notes.

However, varieties need to do more than just survive harsh weather conditions. Breeders face a daunting task of incorporating as many traits as possible to cater to the overarching and the specific interests of multiple farmers. As Murenga Mwimali, a maize breeder at the Kenya Agricultural and Livestock Research Organization (KALRO) and collaborator in this research says, innovations in breeding technologies are making breeding more efficient.

“It is better to have a diversity of product profiles as different market niches are captured within a particular agroecological zones. This is such that farmers may not just benefit from the minimum traits like drought tolerance, but also more specific traits they are looking for,” Mwimali says.

Smallholder farmers continue to play a central role in the seed development process. Capturing what happens at the point of purchase, for instance, at the agrodealer, and understanding how they purchase seed offers valuable insights on the traits that are deemed essential in the breeding process. This work contributes to CIMMYT’s focus on fast-tracking varietal turnover by turning the levers towards a demand-driven seed system.

Cover photo: Pauline Muindi, gender research associate with CIMMYT, at the mock agrodealer shop where she acted as a clerk. (Photo: CIMMYT)

Farmers at a demonstration farm field day organized by East African Seed Company. (Photo: Courtesy)

Fighting the stress

Written by Rodrigo Ordóñez on March 23, 2021. Posted in Features.

East African Seed Company has a rich history of nearly 50 years, serving farmers with improved climate-resilient seed varieties. Established in 1972, the company produces and sells improved seed, through a wide distribution network in at least 15 countries in sub-Saharan Africa. It also markets agrochemicals and other farm inputs, and has ambitions of expanding to the rest of Africa, trading as Agriscope Africa Limited.

Smallholder farmers in sub-Saharan Africa continue to face multiple biotic and abiotic stresses as they try to improve their farms’ productivity and their livelihoods. Maize seed that guarantees high yield is a key trait, coupled with other key attributes such as drought tolerance, disease and pest resistance, early seedling vigor as well as suitability for food and animal feed.

With the varieties serving both small- and large-scale commercial farmers, challenges such as the fall armyworm, diminishing soil fertility and erratic rains have persisted in recent years and remain as key farming obstacles. “Such challenges diminish crop production and the grain quality thereby, lessening farmers’ profitability,” says Rogers Mugambi, Chief Operating Officer of East African Seed Company.

Scientists at the International Maize and Wheat Improvement Center (CIMMYT), in collaboration with partners in the national agriculture research systems and the commercial seed sector, continue to develop seed varieties that can guarantee decent yield even in times of climatic, disease and pest stress.

General view of the East African Seed warehouse. (Photo: Jerome Bossuet/CIMMYT)

Top-notch research trickles down to farmers

Over the years, East African Seed has inked partnerships with CIMMYT, national research institutes and other agencies in the countries where it operates. Such partnerships have been the driving force to its success and the impacts within the farming communities in sub-Saharan Africa.

“Our collaboration with CIMMYT began in 2008 with germplasm acquisition. The cooperation has expanded to include testing networks for new hybrids, early-generation seed production and marketing. The overall beneficiary is the smallholder farmer who can access quality seeds and produce more with climate-smart products,” Mugambi says.

Apart from the multi-stress-tolerant varieties developed and released over time by the national agricultural research programs, CIMMYT recently announced a breakthrough: fall armyworm-tolerant elite maize hybrids for eastern and southern Africa. This success followed three years of rigorous research and experiments conducted in Kenya and signified a key milestone in the fight against fall armyworm.

As part of the partnership in the Drought Tolerant Maize for Africa (DTMA) and Stress Tolerant Maize for Africa (STMA) projects, East African Seed Company (Agriscope Africa Limited) established demonstration farms and conducted field days in Kenya, reaching thousands of farmers as a result. It was also able to produce early generation seed, which supported production of 2,000 metric tons of certified seed. This partnership now continues in the Accelerating Genetic Gains in Maize and Wheat (AGG) project.

The company has contracted large- and small-scale growers across the country to meet its seed production targets.

“Most of our small-scale growers are clustered in groups of up to 30 farmers with less than five acres of farmland. The large growers have advanced irrigation facilities such as the pivot system and seed processing plants. The seed from the fields is pre-cleaned and dried in the out-grower facilities before delivery to our factory for further cleaning and processing,” Mugambi explains.

A handful of improved maize seed from the drought-tolerant variety TAN 250, developed and registered for sale in Tanzania through CIMMYT's Drought Tolerant Maize for Africa (DTMA) project. (Photo: Anne Wangalachi/CIMMYT) — A handful of improved maize seed from the drought-tolerant variety TAN 250, developed and registered for sale in Tanzania through CIMMYT’s Drought Tolerant Maize for Africa (DTMA) project. (Photo: Anne Wangalachi/CIMMYT)

Out with the drought

Currently, of the 1,300 metric tons of drought-tolerant hybrid seeds it produces yearly, 500 metric tons constitute those derived from the partnership in the STMA project. Two notable hybrids, HODARI (MH501) and TOSHEKA (MH401), were derived during the DTMA and STMA projects. Released in 2014 and accepted for regional certification through the Common Market for Eastern and Southern Africa (COMESA)’s regional catalogue, the MH501 is a mid-altitude adapted and medium maturing three-way cross hybrid. The yield advantage of 15% over the local commercial checks triggered widespread adoption by the farmers, according to Mugambi. In Kenya, it was used as a commercial check during national performance trials, from 2017 to 2019.

The MH401, an early maturing hybrid with moderate drought tolerance, has been adopted in lowland and mid-altitude dry ecologies of Kenya and Tanzania. It has a 20% yield advantage over the local commercial checks.

As part of its varietal replacement, East African Seed Company looks to steadily retire older varieties such as KH600-15A and WE1101 and promote new ones including TAJIRI (EASH1220), TAJI (MH502) and FARAJA (MH503).

To promote new varieties and successfully reach smallholders, the company conducts field days, farm-level varietal demonstrations, road shows and radio programs. It also disseminates information on the benefits of new varieties while also dispensing promotional materials such as branded t-shirts and caps.

“Additionally, we organize annual field days at our research farm in Thika, where key and influential farmers and other stakeholders are invited from across Kenya and neighboring countries to learn about our new agricultural technologies,” Mugambi says.

Alinda Sarah shows a maize cob due for harvest on the farm she owns with her husband in Masindi, mid-western Uganda. (Photo: Joshua Masinde/CIMMYT)

Researchers identify optimal strategy to maximize genomic estimated breeding values

Written by Marcia MacNeil on March 3, 2021. Posted in News.

The ultimate challenge for crop breeders is to increase genetic gain of a crop: literally, to increase the crop’s yield on farmers’ fields. Wheat and maize breeders from the International Maize and Wheat Improvement Center (CIMMYT) and partner institutions are working to achieve this in record time, developing new varieties tailored for farmers’ needs that are also pest- and disease-resistant, climate-resilient, and nutritious.

This work is part of the Accelerating Genetic Gain in Maize and Wheat for Improved Livelihoods (AGG) project. Among other methods, breeders are using state-of-the-art novel tools such as genomic selection to achieve this ambitious goal.

In genomic selection, breeders use information about a plant’s genetic makeup along with data on its visible and measurable traits, known as phenotypic data, to “train” a model to predict how a cross will turn out — information known as “genomic estimated breeding values (GEBV)” — without having to plant seeds, wait for them to grow, and physically measure their traits. In this way, they save time and costs by reducing the number of selection cycles.

However, research is still ongoing about the best way to use genomic selection that results in the most accurate predictions and ultimately reduces selection cycle time. A recent publication by CIMMYT scientist Sikiru Atanda and colleagues has identified an optimal genomic selection strategy that maximizes the efficiency of this novel technology. Although this research studied CIMMYT’s maize breeding programs, AGG scientists working on wheat genetic gain and zinc nutritional content see cross-crop impacts.

Shortening a lengthy process

In the typical breeding stages, breeders evaluate parental lines to create new crosses, and advance these lines through preliminary and elite yield trials. In the process, thousands of lines are sown, grown and analyzed, requiring considerable resources. In the traditional CIMMYT maize breeding scheme, for example, breeders conduct five stages of testing to identify parental lines for the next breeding cycle and develop high yielding hybrids that meet farmers’ needs.

In the current scheme using genomic selection, breeders phenotype 50% of a bi-parental population to predict the GEBVs of the remaining un-tested 50%. Though this reduces the cost of phenotyping, Atanda and his co-authors suggest it is not optimal because the breeder has to wait three to four months for the plant to grow before collecting the phenotypic data needed to calibrate the predictive model for the un-tested 50%.

Atanda and his colleagues’ findings specify how to calibrate a model based on existing historical phenotypic and genotypic data. They also offer a method for creating “experimental” sets to generate phenotypic information when the models don’t work due to low genetic connectedness between the new population and historical data.

This presents a way forward for breeders to accelerate the early yield testing stage based on genomic information, reduce the breeding cycle time and budget, and ultimately increase genetic gain.

Regional maize breeding coordinator for Africa Yoseph Beyene explained the leap forward this approach represents for CIMMYT’s maize breeding in Africa.

“For the last 5 years, CIMMYT’s African maize breeding program has applied genomic selection using the ‘test-half-and-predict-half’ strategy,” he said. “This has already reduced operational costs by 32% compared to the traditional phenotypic selection.”

“The prediction approach shown in this paper — using historical data alone to predict untested lines that go directly to stage-two trials — could reduce the breeding cycle by a year and save the cost of testcross formation and multi-location evaluation of stage-one testing. This research contributes to our efforts in the AGG project to mainstream genomic selection in all the product profiles.”

Effective for maize and wheat

Atanda, who now works on the use of novel breeding methods to enhance grain zinc content in CIMMYT’s wheat breeding program, believes these findings apply to wheat breeding as well.

“The implications of the research in maize are the same in wheat: accelerating early testing stage and reducing the breeding budget, which ultimately results in increasing genetic gain,” he said.

CIMMYT Global Wheat Program director Alison Bentley is optimistic about the crossover potential. “It is fantastic to welcome Atanda to the global wheat program, bringing skills in the use of quantitative genetic approaches,” she said. “The use of new breeding methods such as genomic selection is part of a portfolio of approaches we are using to accelerate breeding.”

CIMMYT’s wheat breeding relies heavily on a time-tested and validated method using managed environments to test lines for a range of growing environments — from drought to full irrigation, heat tolerance and more — in CIMMYT’s wheat experimental station in Ciudad Obregón, in Mexico’s state of Sonora.

According to CIMMYT senior scientist and wheat breeder Velu Govindan, using the approaches tested by Sikiru can make this even more efficient. As a specialist in biofortification — using traditional breeding techniques to develop crops with high levels of micronutrients — Govindan is taking the lead mainstreaming high zinc into all CIMMYT improved wheat varieties.

“This process could help us identify best lines to share with partners one year earlier — and it can be done for zinc content as easily as for grain yield.”

If this study seems like an excellent fit for the AGG project’s joint focus on accelerating genetic gain for both maize and wheat, that is no accident.

“The goal of the AGG project was the focus of my research,” Atanda said. “My study has shown that this goal is doable and achievable.”

Read the study:
Maximizing efficiency of genomic selection in CIMMYT’s tropical maize breeding program

Wheat infected with the blast fungus in Meherpur, Bangladesh, in 2019. (Photo: PLOS Biology)

First complete cytological characterization of the 2NvS translocation

Written by Marcia MacNeil on February 23, 2021. Posted in News.

As scientists study and learn more about the complicated genetic makeup of the wheat genome, one chromosomal segment has stood out, particularly in efforts to breed high-yielding wheat varieties resistant to devastating and quickly spreading wheat diseases.

Known as the 2N^vS translocation, this segment on the wheat genome has been associated with grain yield, tolerance to wheat stems bending over or lodging, and multiple-disease resistance.

Now, thanks to a new multi-institution study led by wheat scientist Liangliang Gao of Kansas State University, we have a clearer picture of the yield advantage and disease resistance conferred by this chromosomal segment for wheat farmers — and more opportunities to capitalize on these benefits for future breeding efforts.

The Aegilops ventricosa 2N^vS segment in bread wheat: cytology, genomics and breeding, published in Theoretical and Applied Genetics, summarizes the collaborative effort by scientists from several scientific institutions — including International Maize and Wheat Improvement Center (CIMMYT) head of global wheat improvement Ravi Singh and wheat scientist Philomin Juliana — to conduct the first complete cytological characterization of the 2N^vS translocation.

A rich background

The 2N^vS translocation segment has been very valuable in disease-resistance wheat breeding since the early 1990s. Originally introduced into wheat cultivar VPM1 by the French cytogeneticist Gerard Doussinault in 1983 by crossing with a wild wheat relative called Aegilops ventricosa, the segment has been conferring resistance to diseases like eye spot (Pch1 gene), leaf rust (Lr37 gene), stem rust (Sr38 gene), stripe rust (Yr17 gene), cereal cyst (Cre5 gene), root knot (Rkn3 gene) and wheat blast.

The high-yielding blast-resistant CIMMYT-derived varieties BARI Gom 33 and WMRI#3 (equivalent to Borlaug100),released in Bangladesh to combat a devastating outbreak of wheat blast in the region, carry the 2N^vS translocation segment for blast resistance.

Earlier research by Juliana and others found that the proportion of lines with the 2N^vS translocation had increased by 113.8% over seven years in CIMMYT’s international bread wheat screening nurseries: from 44% in 2012 to 94.1% in 2019. It had also increased by 524.3% in the semi-arid wheat screening nurseries: from 15% in 2012 to 93.7% in 2019. This study validates these findings, further demonstrating an increasing frequency of the 2N^vS translocation in spring and winter wheat breeding programs over the past two decades.

New discoveries

The authors of this study completed a novel assembly and functional annotation of the genes in the 2N^vS translocation using the winter bread wheat cultivar Jagger. They validated it using the spring wheat cultivar CDC Stanley and estimated the actual size of the segment to be approximately 33 mega base pairs.

Their findings substantiate that the 2N^vS region is rich in disease resistance genes, with more than 10% of the 535 high-confidence genes annotated in this region belonging to the nucleotide-binding leucine-rich repeat (NLR) gene families known to be associated with disease resistance. This was a higher number of NLRs compared to the wheat segment of the Chinese Spring reference genome that was replaced by this segment, adding further evidence to its multiple-disease resistant nature.

In addition to being an invaluable region for disease resistance, the study makes a strong case that the 2N^vS region also confers a yield advantage. The authors performed yield association analyses using yield data on lines from the Kansas State University wheat breeding program, the USDA Regional Performance Nursery —comprising lines from central US winter wheat breeding programs — and the CIMMYT spring bread wheat breeding program, and found a strong association between the presence of the segment and higher yield.

Global benefits

The yield and disease resistance associations of the 2N^vS genetic segment have been helping farmers for years, as seen in the high proportion of the segment present in the improved wheat germplasm distributed globally through CIMMYT’s nurseries.

“The high frequency of the valuable 2N^vS translocation in CIMMYT’s internationally distributed germplasm demonstrates well how CIMMYT has served as a key disseminator of lines with this translocation globally that would have likely contributed to a large impact on global wheat production,” said study co-author Juliana.

Through CIMMYT’s distribution efforts, it is likely that national breeding programs have also effectively used this translocation, in addition to releasing many 2N^vS-carrying varieties selected directly from CIMMYT distributed nurseries.

With this study, we now know more about why the segment is so ubiquitous and have more tools at our disposal to use it more deliberately to raise yield and combat disease for wheat farmers into the future.

The new interactive map allows visitors to visually explore the milestones that allowed a global network of researchers to fight threats to wheat production.

The global network safeguarding the world’s wheat

Written by Rodrigo Ordóñez on February 23, 2021. Posted in News.

In 2005, preeminent wheat breeder and Nobel Laureate Norman E. Borlaug sounded the alarm to bring the world’s attention to the outbreak of a new variant of stem rust, Ug99, that threatened to wipe out 80% of the world’s wheat.

The result was the Borlaug Global Rust Initiative (BGRI), a global community that pioneered innovative ways for scientists and smallholder farmers around the globe to collaborate on meeting challenges brought about by wheat disease and climate change.

As a founding member of BGRI, the International Maize and Wheat Improvement Center (CIMMYT) and, later, the CGIAR Research Program on Wheat, played a crucial role in the core work of the initiative. They led breeding and large-scale international testing to develop disease resistant wheat varieties, coordinated closely with longstanding national partners to facilitate the release and spread of the varieties to farmers, and contributed to critical disease monitoring and tracking initiatives.

The BGRI has documented these efforts and related resources in a newly released interactive story map: Inside the global network safeguarding the world’s wheat from disease and climate change. The map highlights the BGRI’s efforts from 2005 to 2020 to introduce climate-resilient, disease-resistant wheat to resource-constrained wheat growers around the world, especially in sub-Saharan Africa and South Asia.

When a disease threatens to destroy the world’s most important food crop, who do you call?

The map highlights work undertaken by scientists on the front lines of the Durable Rust Resistance in Wheat (DRRW) and Delivering Genetic Gain in Wheat (DGGW) projects from 2005 to 2020. These achievements formed the foundation for the work that continues today under the auspices of the CIMMYT-led Accelerating Genetic Gains In Maize and Wheat for Improved Livelihoods (AGG) project.

BGRI scientists from more than 22 national and international agricultural research centers infused resilience into wheat and largely staved off large-scale rust epidemics, working with farmers in East Africa, South Asia and other important bread baskets of the world. The BGRI community improved breeding pipelines, created the world’s most sophisticated pathogen surveillance network, increased capacity in germplasm testing nurseries while conserving and sharing genetic resources, and training new generations of young scientists.

Through videos, photos, interviews, journal articles, blogs, news stories and other resources, the map allows visitors to explore the multifaceted work from hunger fighters in Australia, Canada, China, Ethiopia, India, Kenya, Mexico, Nepal, Russia, the United Kingdom, the United States and other countries.

Written and produced by BGRI cinematographer Chris Knight and associate director for communications Linda McCandless, the map is linked to multimedia and resources from contributors around the world.

Browse the interactive story map:
Inside the Global Network Safeguarding the World’s Wheat from Disease and Climate Change

The DRRW and DGGW projects received funding from the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth and Development Office, national research institutes, and Cornell University.

Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) brings together partners in the global science community and in national agricultural research and extension systems to accelerate the development of higher-yielding varieties of maize and wheat — two of the world’s most important staple crops. Funded by the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth & Development Office (FCDO), the U.S. Agency for International Development (USAID) and the Foundation for Food and Agriculture Research (FFAR), AGG fuses innovative methods that improve breeding efficiency and precision to produce and deliver high-yielding varieties that are climate-resilient, pest- and disease-resistant, highly nutritious, and targeted to farmers’ specific needs.

Research reported in this story was supported by the Foundation for Food and Agriculture Research under award number Grant ID COTF0000000001. The content of this publication is solely the responsibility of the authors and does not necessarily represent the official views of the Foundation for Food and Agriculture Research.

Alice Nasiyimu stands in front of a drought-tolerant maize plot at her family farm in Bungoma County, in western Kenya. (Photo: Joshua Masinde/CIMMYT)

Q&A: A decade of improved and climate-smart maize through collaborative research and innovation

Written by Shiela Chikulo on February 23, 2021. Posted in Features.

The food security and livelihoods of smallholder farming families in sub-Saharan Africa depend on maize production. The region accounts for up to two-thirds of global maize production, but is facing challenges related to extreme weather events, climate-induced stresses, pests and diseases, and deteriorating soil quality. These require swift interventions and innovations to safeguard maize yields and quality.

In this Q&A, we reflect on the results and impact of the long-term collaborative work on drought-tolerant maize innovations spearheaded by two CGIAR Research Centers: the International Maize and Wheat Improvement Center (CIMMYT) and International Institute of Tropical Agriculture (IITA). This innovative work has changed guises over the years, from the early work of the Drought Tolerant Maize for Africa (DTMA) and Drought Tolerant Maize for Africa Seed Scaling (DTMASS) projects through later iterations such as Stress Tolerant Maize for Africa (STMA) and the newest project, Accelerating Genetic Gains in Maize and Wheat (AGG).

In this Q&A, three leaders of this collaborative research reflect on the challenges their work has faced, the innovations and impact it has generated for smallholder farmers, and possible directions for future research. They are: B.M Prasanna, director of CIMMYT’s Global Maize Program and of the CGIAR Research Program on Maize (MAIZE); Abebe Menkir, a maize breeder and maize improvement lead at IITA; and Cosmos Magorokosho, project lead for AGG-Maize at CIMMYT.

Briefly describe the challenges confronting small-scale farmers prior to the introduction of drought-tolerant maize and how CIMMYT and IITA responded to these challenges?

B.M.P.: Maize is grown on over 38 million hectares in sub-Saharan Africa, accounting for 40% of cereal production in the region and providing at least 30% of the population’s total calorie intake. The crop is predominantly grown under rainfed conditions by resource-constrained smallholder farmers who often face erratic rainfall, poor soil fertility, increasing incidence of climatic extremes — especially drought and heat — and the threat of devastating diseases and insect pests.

Around 40% of maize-growing areas in sub-Saharan Africa face occasional drought stress with a yield loss of 10–25%. An additional 25% of the maize crop suffers frequent drought, with yield losses of up to 50%. Climate change is further exacerbating the situation, with devastating effects on the food security and livelihoods of the millions of smallholder farmers and their families who depend on maize in sub-Saharan Africa. Therefore, the improved maize varieties with drought tolerance, disease resistance and other farmer-preferred traits developed and deployed by CIMMYT and IITA over the last ten years in partnership with an array of national partners and seed companies across sub-Saharan Africa are critical in effectively tackling this major challenge.

A.M.: Consumption of maize as food varies considerably across sub-Saharan Africa, exceeding 100 kg per capita per year in many countries in southern Africa. In years when rainfall is adequate, virtually all maize consumed for food is grown in sub-Saharan Africa, with a minimal dependence on imported grain. Maize production, however, is highly variable from year to year due to the occurrence of drought and the dependence of national maize yields on seasonal rainfall. One consequence has been widespread famine occurring every five to ten years in sub-Saharan Africa, accompanied by large volumes of imported maize grain as food aid or direct imports.

This places a significant strain on resources of the World Food Programme and on national foreign exchange. It also disincentivizes local food production and may not prevent or address cyclical famine. It also leaves countries ill-equipped to address famine conditions in the period between the onset of the crisis and the arrival of food aid. Investment in local production, which would strengthen the resilience and self-sufficiency in food production of smallholder farming families, is a far better option to mitigate food shortages than relying on food aid and grain imports.

C.M.: Smallholder farmers in sub-Saharan Africa face innumerable natural and socioeconomic constraints. CIMMYT, in partnership with IITA and national agricultural research system partners, responded by developing and catalyzing the commercialization of new maize varieties that produce reasonable maize yields under unpredictable rainfall-dependent growing season.

Over the life of the partnership, more than 300 new climate-adaptive maize varieties were developed and released in more than 20 countries across sub-Saharan Africa where maize is a major staple food crop. Certified seed of over 100 stress-tolerant improved maize varieties have been produced by seed company partners, reaching more than 110,000 tons in 2019. The seeds of these drought-tolerant maize varieties have benefited more than 8 million households and were estimated to be grown on more than 5 million hectares in eastern, southern and west Africa in 2020.

A farmer in Mozambique stands for a photograph next to her drought-tolerant maize harvest. (Photo: CIMMYT)

In what ways did the drought-tolerant maize innovation transform small-scale farmers’ ability to respond to climate-induced risks? Are there any additional impacts on small scale farmers in addition to climate adaptation?

B.M.P.: The elite drought-tolerant maize varieties can not only provide increased yield in drought-stressed crop seasons, they also offer much needed yield stability. This means better performance than non-drought-tolerant varieties in both good years and bad years to a smallholder farmer.

Drought-tolerant maize varieties developed by CIMMYT and IITA demonstrate at least 25-30% grain yield advantage over non-drought-tolerant maize varieties in sub-Saharan Africa under drought stress at flowering. This translates into at least a 1 ton per hectare enhanced grain yield on average, as well as reduced downside risk in terms of lost income, food insecurity and other risks associated with crop yield variability. In addition to climate adaptation, smallholder farmers benefit from these varieties due to improved resistance to major diseases like maize lethal necrosis and parasitic weeds like Striga. We have also developed drought-tolerant maize varieties with enhanced protein quality — such as Quality Protein Maize or QPM — and provitamin A, which improve nutritional outcomes.

We must also note that drought risk in sub-Saharan Africa has multiple and far-reaching consequences. It reduces incentives for smallholder farmers to intensify maize-based systems and for commercial seed companies to invest and evolve due to a limited seed market.

Drought-tolerant maize is, therefore, a game changer as it reduces the downside risk for both farmers and seed companies and increases demand for improved maize seed, thus strengthening the commercial seed market in sub-Saharan Africa. Extensive public-private partnerships around drought-tolerant maize varieties supported the nascent seed sector in sub-Saharan Africa and has enabled maize-based seed companies to significantly grow over the last decade. Seed companies in turn are investing in marketing drought-tolerant maize varieties and taking the products to scale.

A.M.: The DTMA and STMA projects were jointly implemented by CIMMYT and IITA in partnership with diverse national and private sector partners in major maize producing countries in eastern, southern and western Africa to develop and deploy multiple stress-tolerant and productive maize varieties to help farmers adapt to recurrent droughts and other stresses including climate change.

These projects catalyzed the release and commercialization of numerous stress-resilient new maize varieties in target countries across Africa. Increasing the resilience of farming systems means that smallholder farmers need guaranteed access to good quality stress resilient maize seeds. To this end, the two projects worked with public and private sector partners to produce large quantities of certified seeds with a continual supply of breeder seeds from CIMMYT and IITA. The availability of considerable amount of certified seeds of resilient maize varieties has enabled partners to reach farmers producing maize under stressful conditions, thus contributing to the mitigation of food shortages that affect poor people the most in both rural and urban areas.

C.M.: The drought-tolerant maize innovation stabilized maize production under drought stress conditions in sub-Saharan Africa countries. Recent study results showed that households that grew drought-tolerant maize varieties had at least half a ton more maize harvest than the households that did not grow the drought-tolerant maize varieties, thus curbing food insecurity while simultaneously increasing farmers’ economic benefits. Besides the benefit from drought-tolerant innovation, the new maize varieties developed through the partnership also stabilized farmers’ yields under major diseases, Striga infestation, and poor soil fertility prevalent in sub-Saharan Africa.

How is the project addressing emerging challenges in breeding for drought-tolerant maize and what opportunities are available to address these challenges in the future?

Margaret holds an improved ear of drought-tolerant maize. Margaret’s grandmother participated in an on-farm trial in Murewa district, 75 kilometers northeast of Zimbabwe’s capital Harare. (Photo: Jill Cairns/CIMMYT)

B.M.P.: A strong pipeline of elite, multiple-stress-tolerant maize varieties — combining other relevant adaptive and farmer-preferred traits — has been built in sub-Saharan Africa through a strong germplasm base, partnerships with national research partners and small- and medium-sized seed companies, an extensive phenotyping and multi-location testing network, and engagement with farming communities through regional on-farm trials for the identification of relevant farmer-preferred products.

CGIAR maize breeding in sub-Saharan Africa continues to evolve in order to more effectively and efficiently create value for the farmers we serve. We are now intensively working on several areas: (a) increasing genetic gains (both on-station and on-farm) through maize breeding in the stress-prone environments of sub-Saharan Africa by optimizing our breeding pipelines and effectively integrating novel tools, technologies and strategies (e.g., doubled haploids, genomics-assisted breeding, high-throughput and precise phenotyping, improved breeding data management system, etc.); (b) targeted replacement of old or obsolete maize varieties in sub-Saharan Africa with climate-adaptive and new varieties; (c) developing next-generation climate-adaptive maize varieties with traits such as native genetic resistance to fall armyworm, and introgressed nutritional quality traits (e.g., provitamin A, high Zinc) to make a positive impact on the nutritional well-being of consumers; and (d) further strengthening the breeding capacity of national partners and small and medium-sized seed companies in sub-Saharan Africa for a sustainable way forward.

A.M.: The DTMA and STMA projects established effective product pipelines integrating cutting-edge phenotyping and molecular tools to develop stress-resilient maize varieties that are also resistant or tolerant to MLN disease and fall armyworm. These new varieties are awaiting release and commercialization. Increased investment in strengthening public and private sector partnerships is needed to speed up the uptake and commercialization of new multiple stress-resilient maize varieties that can replace the old ones in farmers’ fields and help achieve higher yield gains.

Farmers’ access to new multiple-stress-tolerant maize varieties will have a significant impact on productivity at the farm level. This will largely be due to new varieties’ improved response to fertilizer and favorable growing environments as well as their resilience to stressful production conditions. Studies show that the adoption of drought-tolerant maize varieties increased maize productivity, reduced exposure to farming risk among adopters and led to a decline in poverty among adopters. The availability of enough grain from highly productive and stress-resilient maize varieties can be the cheapest source of food and release land to expand the cultivation of other crops to facilitate increased access to diversified and healthy diets.

C.M.: The project is tackling emerging challenges posed by new diseases and pests by building upon the successful genetic base of drought-tolerant maize. This is being done by breeding new varieties that add tolerance to the emerging disease and pest challenges onto the existing drought-tolerant maize backgrounds. Successes have already been registered in breeding new varieties that have high levels of resistance to MLN disease and the fall armyworm pest.

Opportunities are also available to address new challenges including: pre-emptively breeding for threats to maize production challenges that exist in other regions of the world before these threats reach sub-Saharan Africa; enhancing the capacity of national partners to build strong breeding programs that can address new threats once they emerge in sub-Saharan Africa; and sharing knowledge and novel high-value breeding materials across different geographies to immediately address new threats once they emerge.

Cover photo: Alice Nasiyimu stands in front of a drought-tolerant maize plot at her family farm in Bungoma County, in western Kenya. (Photo: Joshua Masinde/CIMMYT)