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Tag: maize breeding

Deployment of new tools and technologies into the CGIAR-NARS breeding program increases the rate of genetic gain per dollar invested

Written by dmedina on . Posted in Publications.

Food security in the prevailing uncertain climatic and economic conditions can only be guaranteed by deliberate actions toward maximizing production, especially in stress-prone environments. The main priority of the CGIAR and NARS breeding programs is to enhance genetic gain in crops through the assessment of seed varieties with drought-resilient, nutritional, and yield traits. This is achieved by leveraging data-driven approaches and embracing contemporary tools and methodologies.

Innovative approaches such as molecular tools, doubled haploid technology, and refined breeding schemes have greatly contributed to the strides made in CIMMYT’s endeavor to elevate genetic gain within breeding pipelines. These advancements not only drive improved productivity but also promise cost-effective strategies for navigating the challenges posed by climate variability.

Molecular Tools

In maize breeding, traditionally, at each stage of the pipeline, entries are grown in multi-location trials. Phenotyping in multiple environments helps to select the best entries not only based on their genetic values but also on environmental factors and their interaction with diverse environments. However, this is also a labor-intensive and time-consuming step in the breeding pipeline. Molecular breeding offers a transformative solution by expanding breeding programs while minimizing phenotyping requirements. It is a well-known fact that trait phenotype results from both genetic and non-genetic factors, with genetic factors being contributed by the expression of genes at the DNA level.

Identifying genomic regions close to causative genes for traits of interest, such as high yield, disease resistance, or quality, can help to incorporate desirable genes/alleles into selected elite genotypes. DNA-based markers aid in efficiently tracking the inheritance of genetic traits, thereby facilitating the selection of desired traits in breeding programs. Marker-assisted forward breeding accelerates the selection of plants with desired traits by identifying the genetic markers associated with those traits. With such harnessed genotypic information, breeders can pre-select genetic material before embarking on the resource-intensive phenotyping stages. This strategic utilization of molecular markers, particularly in identifying susceptibility to key diseases like maize streak virus (MSV) and maize lethal necrosis (MLN), enables the judicious allocation of resources for phenotyping.

 

Figure 1. Summary of marker-assisted forward breeding across six breeding pipelines for MLN- and MSV-resistance haplotypes over the past six years.

Since 2018, CIMMYT has been implementing marker-assisted forward breeding for MSV and MLN. Since then, more than 100,000 pure breeding lines have been tested by examining their favorable haplotypes with a small set of 10 genetic markers and discarding the lines carrying unfavorable haplotypes for MSV and MLN resistance. In the last six years, nearly 30,000 lines have been rejected before undergoing field testing. In southern Africa, for instance, a rapid response to seed movement using molecular and serological techniques prevented the spread of MLN and facilitated the incorporation of resistance traits into new plant varieties.

Most hybrids in the final stages of breeding pipelines are passed through forward breeding. While Fall Armyworm, Gray Leaf Spot, common rust, and Turcicum Leaf Blight also cause substantial yield reductions in sub-Saharan Africa, research carried out under the AGG project indicates that the genetic makeup of these traits is oligogenic, governed by both moderate and small effect quantitative trait loci (QTLs), but lacking a single major-effect QTL and not amenable to forward breeding. This means that their resistance is influenced by complex multiple genetic factors, rather than being primarily controlled by a few major genetic regions. Alternatively, these biotic stress traits can be improved effectively through genomic selection.

Genomic selection is used to improve complex traits that are controlled by many small-effect QTLs. This approach does not require prior genetic information about the trait of interest and uses genome-wide marker information to estimate all marker effects and select individuals with high genomic-estimated breeding values (GEBVs). This means it uses data from various genetic markers to predict which individuals are likely to have desirable alleles for MSV and MLN. Genomic selection is being applied for grain yield under drought stress, and efforts are underway to extend its application to address more complex challenges related to plant diseases and pests. Foliar diseases are moderately complex traits.

Proof of concept on applying genomic selection for foliar diseases like gray leaf spot and northern corn leaf blight showed high prediction accuracies, supporting the implementation of genomic selection together with forward breeding for other traits at the early stage of the breeding pipeline. Implementing genomic selection for GY under optimum and drought management proved that maize breeders could obtain the same gain as with conventional breeding, where all entries are phenotyped in the field, but at approximately 35-40% less cost. Many candidate hybrids now entering the advanced stages of the breeding pipeline were developed using genomic selection. Several of our earlier studies (Beyene et al., 2015, 2016, 2019, 2021; Chaikam et al., 2019; Crossa et al., 2017; Prasanna et al., 2022; Vivek et al., 2017) showed that breeding pipelines achieved high genetic gain by adopting new molecular tools, thus confirming the benefit of adopting molecular breeding tools.

Currently, in CIMMYT’s eastern and southern breeding pipelines, all product profiles are using genomic selection at stage I, where the training population is evaluated in multiple locations with a sparse design, estimating the GEBVs for the unphenotyped lines, and using GEBVs and phenotypic BLUPs of test crosses in the selection for stage II. This process allows the handling of a large number of lines at stage I with a fixed budget without losing selection accuracy. Since 2017, we have used the “test half and predict half” strategy (Figure 2), where all the lines were genotyped with mid-density markers, and the selected ~50% of the total stage I lines were testcrossed and evaluated in multiple locations to be used as a training population to estimate the GEBVs for the other 50% of the unphenotyped lines for the traits of interest. High prediction correlations were observed in three selected product profiles for GY under optimum, managed drought, and low soil N conditions (Figure 3).

Genomic selection is also implemented to reduce the breeding cycle. However, our final products are three-way cross hybrids, where genomic selection is applied only to select the best line rather than selecting the best hybrid combinations. Historical data were used to test the possibility of reducing the breeding cycle. However, our results showed that the use of historical data to predict 100% of lines from the current year yielded low to moderate prediction correlations both under optimum and drought conditions for GY, anthesis date, and plant height (Figure 4). Incorporating 10 to 30% of the testing population into the training population leads to high prediction correlations. This concludes that by using historical data, the training population, which needs to be test-crossed and evaluated in multiple locations every year, can be reduced from 50% to 10-30%, which helps breeders allocate the saved resources to evaluate more lines without losing prediction accuracy.

Doubled Haploid Technology

Doubled haploid technology speeds up the creation of inbred lines by producing entirely uniform lines. Pedigree line development is a traditional method in plant breeding aimed at gradually improving and stabilizing the genetic makeup of the new variety over time. It involves multiple generations of controlled crosses between parent plants with known characteristics. Each subsequent generation is carefully selected based on specific traits of interest, such as yield, disease resistance, or quality. Pedigree line development is expensive, particularly when nurseries are in remote locations.

Unlike traditional methods where some genetic variation remains, doubled haploid lines are completely homogeneous. This means that there is increased heritability of desirable traits and improved accuracy of selection. Doubled haploid technology, which is more compatible with the use of molecular markers, simplifies breeding processes and shortens the time needed to develop inbred lines (Chaikam et al., 2019).

The first doubled haploid facility in Africa was established in 2013 and is extensively used by the CGIAR, NARES, and the private sector. Over the past five years, 1,349 populations have been induced and more than 223,144 doubled haploid lines delivered to breeding programs from CGIAR, NARES, and the private sector in sub-Saharan Africa. Shifting from traditional pedigree-based breeding to doubled haploid technology has shown a high impact on key breeding metrics (gain per cycle and gain per year) not only in CIMMYT but also in national partners’ breeding programs, thus increasing genetic gain within the available budget.

Figure 2. Number of lines evaluated with phenotypic selection (PS) and genomic selection (GS) at stage I in EAPP1 product profile from 2017 to 2023. (PS – phenotypic selection, GS – genomic selection)
Figure 3. Prediction correlations for grain yield (GY) under optimum (OPT), drought (MDt) and low soil N (low N) management conditions in EAPP1, EAPP2 and SAPP1 at stage I in 2023

 

Figure 4. Prediction accuracies for grain yield (GY), anthesis date (AD) and plant height (PH) estimated from independent validation schemes using a training population (TRN) consisting of 2017- and 2018-years breeding data and 10%, 30%, 50%, 70% and 90% of 2019 data converted from the testing population (TST) to the training population under optimum and managed drought conditions

 

References

Beyene, Y., Gowda, M., Olsen, M., Robbins, K. R., Pérez-Rodríguez, P., Alvarado, G., Dreher, K., Gao, S. Y., Mugo, S., and Prasanna, B. M. (2019). Empirical comparison of tropical maize hybrids selected through genomic and phenotypic selections. Frontiers in plant science 10, 1502.

Beyene, Y., Gowda, M., Pérez-Rodríguez, P., Olsen, M., Robbins, K. R., Burgueño, J., Prasanna, B. M., and Crossa, J. (2021). Application of genomic selection at the early stage of breeding pipeline in tropical maize. Frontiers in Plant Science 12, 685488.

Beyene, Y., Gowda, M., Suresh, L. M., Mugo, S., Olsen, M., Oikeh, S. O., Juma, C., Tarekegne, A., and Prasanna, B. M. (2017). Genetic analysis of tropical maize inbred lines for resistance to maize lethal necrosis disease. Euphytica 213.

Beyene, Y., Semagn, K., Crossa, J., Mugo, S., Atlin, G. N., Tarekegne, A., et al. (2016). Improving maize grain yield under drought stress and non-stress environments in sub-saharan africa using marker-assisted recurrent selection. Crop Science 56, 344–353. doi: 10.2135/cropsci2015.02.0135

Beyene, Y., Semagn, K., Mugo, S., Tarekegne, A., Babu, R., Meisel, B., Sehabiague, P., Makumbi, D., Magorokosho, C., and Oikeh, S. (2015). Genetic gains in grain yield through genomic selection in eight bi‐parental maize populations under drought stress. Crop Science 55, 154-163.

Chaikam, V., Molenaar, W., Melchinger, A. E., and Prasanna, B. M. (2019). Doubled haploid technology for line development in maize: technical advances and prospects. Theor. Appl. Genet. 132, 3227–3243. doi: 10.1007/s00122-019-03433-x

Crossa, J., Pérez-Rodríguez, P., Cuevas, J., Montesinos-López, O., Jarquín, D., de los Campos, G., et al. (2017). Genomic selection in plant breeding: Methods, models, and perspectives. Trend Plant Sci. 22, 961–975. doi: 10.1016/j.tplants.2017.08.011

Prasanna BM, Burgueño J, Beyene Y, Makumbi D, Asea G, Woyengo V, Tarekegne A, Magorokosho C, Wegary D, Ndhlela T, Zaman-Allah M, Matova PM, Mwansa K, Mashingaidze K, Fato P, Teklewold A, Vivek BS, Zaidi PH, Vinayan MT, Patne N, Rakshit S, Kumar R, Jat SL, Singh SB, Kuchanur PH, Lohithaswa HC, Singh NK, Koirala KB, Ahmed S, San Vicente F, Dhliwayo T, Cairns JE. 2022. Genetic trends in CIMMYT’s tropical maize breeding pipelines. Scientific Reports 12, 20110. https://doi.org/10.1038/s41598-022-24536-4

Vivek, B. S., Krishna, G. K., Vengadessan, V., Babu, R., Zaidi, P. H., Kha, L. Q., et al. (2017). Use of genomic estimated breeding values results in rapid genetic gains for drought tolerance in maize. Plant Genome 10, 1–8. doi: 10.3835/plantgenome2016.07.0070

Unlocking genetic innovations through collaborative pathways

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

Regional partners examine the CIMMYT maize lines displayed during field day. (Photo: CIMMYT)

The International Maize Improvement Consortium for Africa (IMIC-Africa) held its Southern Africa field day on 25 March 2024 at Harare, Zimbabwe. IMIC-Africa, launched by CIMMYT in 2018, is a public-private partnership designed to strengthen maize breeding programs of partner institutions in Africa. As part of this initiative, CIMMYT organizes annual field days which bring together representatives from seed companies and national agricultural research system (NARS) partners across Zimbabwe and Kenya.

At the heart of the IMIC-Africa field day lies a vibrant showcase of genetically diverse materials developed from various maize breeding pipelines of CIMMYT in Southern Africa. Such events serve as a catalyst to drive innovations in maize breeding programs, deliver solutions to stakeholders, and enable seed companies and NARS partners to make informed selections tailored to local contexts.

“It is an important forum to have organized discussions with partners, and redesign—where possible—our breeding approaches to deliver targeted products to stakeholders,” said Director of CIMMYT’s Global Maize Program, One CGIAR Global Maize Breeding Lead, and One CGIAR Plant Health Initiative Lead, B.M. Prasanna. “The main stakeholders here are our partners, including seed companies and public sector national programs, through whom we reach out to farming communities.”

The significance of these field days cannot be overstated. It allows the partners to have a critical look at the breeding materials on display and undertake selections of maize lines relevant to their breeding programs. In addition, the IMIC-Africa field days enable CIMMYT team to have structured dialogues with diverse stakeholders and to review and refine breeding (line and product development) strategies and approaches.

“It is key to bridge the gap between the national programs and private sector players. This platform allows us to stay ahead in terms of research, and innovative breakthroughs in the seed sector,” added Kabamba Mwansa, principal agriculture research officer, ZARI, Zambia and Southern Africa Breeding, and seed systems network coordinator.

Highlights from the Harare field day

With an impressive array of 737 CIMMYT maize lines on display, partners at the Harare field day gained insights about the performance of different materials. The materials span early-, intermediate-, and late- maturity groups to nutritious maize breeding pipelines. This comprehensive showcase enabled seed companies and NARS partners to make informed selections, tailored to their local contexts. The material on display ranged from early generation (one or two years of testing data) to advanced generation (more than three years of testing) coming from the Southern Africa breeding pipelines targeting multiple market segments.

Regional partners examine the CIMMYT maize lines displayed during field day. (Photo: CIMMYT)

One of the strategic priorities of CIMMYT’s maize breeding program in Africa is improving the nutritional quality of maize. This is exemplified by the development of provitamin A-enriched maize (PVA). On display were 169 lines originating from the PVA-enriched maize breeding pipeline. The efforts underscore CIMMYT’s commitment to address regional nutritional needs through targeted breeding initiatives.

Felix Jumbe, a partner from Peacock Seeds in Malawi reflected on the importance of the IMIC-Africa partnership. “We have been part of IMIC-Africa since its inception, and we continue to appreciate the different climate-resilient lines emerging from CIMMYT maize breeding programs in Africa. Last year, we sold out of our seed as people continue to appreciate the need for resilient maize varieties. The drought-tolerant (DT) maize lines from the consortium have been a huge selling point as most farmers are happy with it,” he said.

The field day not only showcased cutting-edge breeding innovations but also offered a historical perspective by tracing the trajectory of the most popular lines taken up under IMIC-Africa from 2019 to 2023. This served as a crucial reference point for partners, enabling them to assess the performance of newly displayed lines against established benchmarks. Furthermore, partners considered the presence of trait donors as invaluable in improving resistance to key biotic stresses or tolerance to certain abiotic stresses prevalent in Africa.

CIMMYT, NARS, and seed company partners participate in the IMIC-Africa field day in Harare, Zimbabwe. (Photo: CIMMYT)

CIMMYT partnership continues to add value

In the face of escalating environmental pressures, including climate change and pest infestations such as the fall armyworm (FAW), CIMMYT breeders have been working tirelessly to develop resilient varieties capable of withstanding these challenges. Partners such as SeedCo have embraced these robust varieties. For breeder Tariro Kusada, it is her second year of attending the IMIC- Africa field day. “We continue to see value in getting breeding materials through IMIC. The vigor from the lines on display is outstanding as compared to last year. We hope the vigor translates to yield.”

Danny Mfula from Synergy Zambia reinforced the value of the partnership. “It is always good to tap into CIMMYT’s germplasm to supplement what we have. We are glad that more FAW-tolerant hybrids are coming on board. We want to leverage on these developments as farmers have gone through a lot of challenges to control FAW,” he said.

As the harvest stage approaches, partners can select their material by assessing the performance of the lines from flowering to grain filling stages. Each plot’s harvest provides invaluable insights, guiding partners in their selections. Partners are also given the opportunity to view the improved maize lines from CIMMYT through a virtual gallery of ears from each plot, ensuring informed decision-making. By fostering dialogue, facilitating partnerships, and highlighting genetic innovations, the field days catalyze progress towards a more sustainable and resilient future for African agriculture.

Heat tolerant maize: a solution for climate change-induced 360◦ water deficits

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

Seed company partners observe the performance of heat-tolerant hybrids in the dry heat of southern Karnataka, India. (Photo: CIMMYT)

Millions of smallholders in the Global South depend on maize, largely cultivated under rainfed conditions, for their own food security and livelihoods. Climate change mediated weather extremes, such as heat waves and frequent droughts, pose a major challenge to agricultural production, especially for rainfed crops like maize in the tropics.

“With both effects coming together under heat stress conditions, plants are surrounded, with no relief from the soil or the air,” said Pervez H. Zaidi, maize physiologist with CIMMYT’s Global Maize Program in Asia. “Climate change induced drought and heat stress results in a double-sided water deficit: supply-side drought due to depleted moisture in soils, and demand-side drought with decreased moisture in the surface air. “

Extreme weather events

Weather extremes have emerged as the major factor contributing to low productivity of the rainfed system in lowland tropics. South Asia is already experiencing soaring high temperatures (≥40◦C), at least 5◦C above the threshold limit for tropical maize and increased frequency of drought stress.

A woman agricultural officer discusses the performance of heat tolerant hybrids at farmers’ field in Raichur districts of Karnataka, India. (Photo: CIMMYT)

“In today’s warmer and drier climate, unless farmers have copious amounts of water (which might not be a sustainable choice for smallholders in the tropics) to not only meet the increased transpiration needs of the plants but also for increased evaporation to maintain necessary levels of humidity in the air, the climate change mediated weather extremes, such as heat and drought pose a major challenge to agricultural production, especially for rainfed crops like maize in lowland tropics,” said Zaidi.

To deal with emerging trends of unpredictable weather patterns with an increased number of warmer and drier days, new maize cultivars must combine high yield potential with tolerance to heat stress.

Maize designed to thrive in extreme weather conditions

CIMMYT’s Global Maize Program in South Asia, in partnership with public sector maize research institutes and private sector seed companies in the region, is implementing an intensive initiative for developing and deploying heat tolerant maize that combines high yield potential with resilience to heat and drought.

By integrating novel breeding and precision phenotyping tools and methods, new maize germplasm with enhanced levels of heat stress tolerance is being developed for lowland tropics. Over a decade of concerted efforts have resulted in over 50 elite heat stress tolerant, CIMMYT-derived maize hybrids licensed to public and private sector partners for varietal release, improved seed deployment, and scale-up.

Popular normal hybrids (left) & CAH153, a heat tolerant hybrid (right) under heat stress. (Photo: CIMMYT)

As of 2023, a total of 22 such high-yielding climate-adaptive maize (CAM) hybrids have been released by partners throughout South Asia. Through public-private partnerships, eight hybrids are being already deployed and scaled-up to over 100,000 hectares in Bangladesh, Bhutan, India, Nepal, and Pakistan. Also, the heat tolerant lines developed by CIMMYT in Asia were used by maize programs in sub-Saharan Africa for developing heat tolerant maize hybrids by crossing these as trait donors with their elite maize lines.

Studies on the new CAM hybrids show that while their yield is like existing normal maize hybrids under favorable conditions, the CAM hybrids outperform normal hybrids significantly under unfavorable weather conditions.

“The unique selling point of the new CAM hybrids is that they guarantee a minimum yield of at least 1.0 tons per hectare to smallholder farmers under unfavorable weather when most of the existing normal hybrids end-up with very poor yield,” said Subhas Raj Upadhyay, from the Lumbini Seed Company Ltd. in Nepal.

Given the superior performance of CAM seeds in stress conditions, Nepali farmers have expressed willingness to pay a premium price: an average of 71% more with government subsidy, or at least 19% extra without a subsidy for CAM seed. Similarly, the farmers in hot-dry areas of the Karnataka state of India are ready to pay 37% premium price for CAM seed compared to normal hybrid seed. These reports strongly validate the demand of CAM seed and therefore a targeted initiative is needed to accelerate deployment and scaling these seeds in climate-vulnerable marginal agroecologies in tropics.

Six new CIMMYT maize hybrids available from South Asia Breeding Program

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

CIMMYT is happy to announce six new, improved tropical maize hybrids that are now available for uptake by public and private sector partners, especially those interested in marketing or disseminating hybrid maize seed across the tropical lowlands of South Asia and similar agroecologies in other regions. NARES and seed companies are hereby invited to apply for licenses to pursue national release, scale-up seed production, and deliver these maize hybrids to farming communities.

How does CIMMYT’s improved maize get to the farmer?
Product Profile Newly available CIMMYT hybrids Basic traits
South Asia Heat + Drought Tolerance (SAHDT) CAH219 Medium maturing, yellow, high yielding, drought and heat tolerant, to FER and TLB
CAH220
South Asia Waterlogging + Drought Tolerance (SAWLDT) CAH214 Medium maturing, yellow, high yielding, drought + waterlogging tolerant, and resistant to FER, TLB and FSR
CAH218
South Asia Drought Tolerance (SADT) CAH216 Medium maturing, yellow, high yielding, drought tolerant, and resistant to TLB and FER
CAH217

 

Performance data Download the CIMMYT-Asia Maize Regional On-Station (Stage 4) and On-Farm (Stage 5) Trials: Results of the 2022-2023 Seasons and Product Announcement from Dataverse.
How to apply Visit CIMMYT’s maize product allocation page for details
Application deadline The deadline to submit applications to be considered during the first round of allocations is 18 June 2024. Applications received after that deadline will be considered during subsequent rounds of product allocations.

 

The newly available CIMMYT maize hybrids were identified through rigorous, years-long trialing and a stage-gate advancement process which culminated in the 2023 South Asia Regional On-Farm Trials. The products were found to meet the stringent performance and farmer acceptance criteria for CIMMYT’s breeding pipelines that are designed to generate products tailored in particular for smallholder farmers in stress-prone agroecologies of South Asia.

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.

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Product Design Teams (PDTs): A client-oriented approach to defining market segments and target product profiles

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

Participants from the Kenya PDT meeting held in Nairobi. (Photo: CIMMYT)

Product design teams (PDTs) are a CGIAR Accelerated Breeding Initiative innovation created to address the aforementioned challenges under the CGIAR-NARES partnership through coordinating SPMS and related TPPs. Each seed product market segment, which in the case of CGIAR is defined at sub-regional level, represents a unique set of requirements. Attached to the segment is a TPP which describes the ideal product to meet the requirements. Taken together, the framework provides a starting point for discussions by breeding teams on investment opportunities.

Discussions on market segments and TPPs need to develop over time as new insights are gained. Some requirements might be overlooked, and others may be emerging due to client requirements and changes in the context. There is a need for a greater understanding of the evolving requirements of the seed companies, farmers, processors, and consumers in the market segments that CGIAR serves. It must be recognized that not all requirements of farmers or consumers are amenable to breeding or efficient to incorporate in breeding pipelines – for example, some post-harvest losses or weed management can be best addressed by appropriate storage mechanisms and improved agronomic practices, respectively.

Product design teams (PDTs) were created to address the aforementioned challenges under the CGIAR-NARES partnership by and coordinating SPMS and related TPPs. A PDT is a group of crop breeding and seed systems stakeholders for a particular crop, who work together to design or redefine TPPs. PDTs have been envisioned to be cross-functional teams that meet annually with the following aims:

  • Review the market segments at subregional and national levels, addressing critical questions, such as:
    • Do the subregional segments capture country-level requirements?
    • What is the opportunity for impact from breeding investments across market segments?
    • Are there important market segments that have not been captured?
    • What are the potential future segments that the team needs to consider?
  • Review and update TPPs for each segment, addressing questions such as:
    • Are any important traits missing?
    • Are country-specific trait values factored?
    • Are country-specific market-dominant varieties included in the market segment?
  • Discuss the needs for market intelligence for the PDT:
    • Unknowns regarding client requirements.
    • Gaps regarding product design parameters.

Director of the Global Maize program at CIMMYT, B.M. Prasanna, said, “PDT meetings serve as an important platform to understand the perspectives of diverse and relevant stakeholders. These discussions enable us to reach a common understanding of the current market requirements and redefine TPPs to reflect needs across value streams through co-creation and shared responsibility.”

The impact of PDTs

Pieter Rutsaert, seed systems specialist at CIMMYT and the CGIAR Market Intelligence Initiative, participated in several PDTs on maize and other crops, such as groundnut. “PDTs are a useful format to understand the unknowns in terms of farmer, processor, and consumer requirements and generate questions that guide future work in market intelligence,” said Rutsaert.

Product Design Team (PDT) meetings bring together breeding and seed systems stakeholders to improve understanding of country and regional needs for a specific crop. (Photo: CIMMYT)

“PDTs will help in routine review of the product requirement for a specific country and will help to remove breeder bias and ensure that all stakeholders’ views are heard and considered”, said Aparna Das, technical program manager for the Global Maize program at CIMMYT.

The main requirements for constituting PDTs for a specific country are:

  • A multidisciplinary team with 7 to 15 members, ensuring diversity of experience and providing reasonable time for decision-making.
  • Must consist of a range of stakeholders, such as: breeders from NARES (often the PDT convener/lead) and CGIAR; representatives of farmers’ groups, seed companies, and food processors; gender specialists; and market intelligence specialists.
  • 30% of members should be female.
  • Should include a member from another crop breeding network, to bring a different perspective.

Bish Das, NARS coordinator, Dragan Milic, breeding specialist, and Lennin Musundire, breeding optimization specialist, from the CGIAR Accelerated Breeding Initiative team said, “Ultimately, the client-led approach to priority setting that CIMMYT’s Global Maize program is implementing in southern and eastern Africa ensures strong alignment with partners’ priorities and client requirements and better targeting of CGIAR regional maize breeding efforts.”

Case study: maize seed systems

CIMMYT’s Global Maize program has refined variety development to meet market needs across the value chain including farmers, processors, and consumers, thus enhancing variety adoption, which is the end goal of breeding pipelines. This has been implemented through the regional CGIAR-NARES-SMEs collaborative breeding networks and having ‘a bottom-up’ approach towards developing market segments and TPPs. This refers to building an understanding of end-users’ needs through inclusive in-country and regional stakeholder PDT meetings. PDTs also ensure that there are CGIAR-NARES-SME defined roles: a national mandate for NARES partners focusing on niche markets, the consolidated national mandate for CGIAR/NARES/SMEs, and a regional mandate for CGIAR Research Centers like CIMMYT.

In 2023, maize PDT teams were established and held meetings for five countries in eastern and southern Africa: Zambia, Ethiopia, Kenya, Zimbabwe, and Uganda. These meetings brought together stakeholders from different fields who play an important role in product development and seed systems (national partners and seed companies), varietal release (representatives from regulatory agencies) and end-product users (for example, millers).

The advantages of TDPs are emphasized by Godfrey Asea, director of Research and Daniel Bomet Kwemoi, maize breeder at the National Agricultural Research Organization (NARO) in Uganda. They highlighted that the NARO maize program has now begun a systematic journey toward modernizing its breeding program. The PDT team validated the country’s market segments and aligned five product profiles with two major target production environments (TPEs), with the mid-altitude regions taking 85% of the maize seed market and the highlands accounting for 15%. “These TPPs will be reviewed annually by the PDT since market segments tend to be dynamic. The breeding program has reclassified and aligned breeding the germplasm to TPPs, which will guide effective resource allocation based on the market shares,” said Asea.

Feedback on PDT meetings so far suggests positive experiences from stakeholders. Wendy Madzura, head of agronomy at SeedCo in Zimbabwe, said, “The unique PDT meeting held at CIMMYT in Zimbabwe provided a conducive environment for public and private stakeholders to have meaningful and honest discussions on the current market segments and TPPs.” Plans for continuous improvement are embedded in the PDT model. “As a follow-up to the PDT meeting, there is a need for further involvement of various stakeholders at the village, ward, and district levels to enable deeper insights and reach because the client needs are constantly changing,” said Madzura.

Building on fifty years of collaboration, a visit by Chinese politicians to CIMMYT in Mexico breeds new opportunities for tackling global agricultural challenges

Written by Sarah McLaughlin on . Posted in News.

Tang Renjian, former governor of Gansu province, China, and current Minister of Agriculture and Rural Affairs and CIMMYT Director General, Bram Govaerts. (Photo: CIMMYT)

The Minister of Agriculture and Rural Affairs for China, Tang Renjian, visited CIMMYT headquarters on Thursday, 11 January, along with dignitaries from the Ministry of Agriculture and Rural Affairs (MARA) and the Embassy of China. Tang, the former governor of Gansu province in China, attended the site with the aim of building on collaborative scientific work between his country and CIMMYT through the Joint Laboratory for Maize and Wheat Improvement in China.

CIMMYT was delighted to host Tang to showcase the benefits of the CIMMYT-China relationship for wheat and maize, and to identify opportunities for sustained collaboration. The highly regarded minister was able to hear about work including genetic analysis service for agriculture and methods to close the gap between farmers and research, as well as to observe CIMMYT’s facilities and field experiments. The meeting laid the foundations for potential future CIMMYT-China projects in areas such as germplasm exchange, molecular breeding, climate-resilient technology, and training.

Bram Govaerts, director general of CIMMYT, said, “Showcasing our science to Tang is an exciting chance for CIMMYT and China to grow what is already a fruitful partnership, impacting millions of people globally.”

Exemplifying impactful global partnerships

Since 1974, the CIMMYT-China relationship has improved the lives of millions of people via numerous evidence-based scientific projects, with support from the Chinese Academy for Agricultural Sciences (CAAS). Through five decades of partnership, the collaboration has resulted in up to 10.7 million additional tons of wheat for China’s national output with a value of US $3.4 million.

CIMMYT’s contribution to China’s wheat and maize is significant. In terms of wheat, 26% of wheat grown in China has been derived from CIMMYT germplasm since the year 2000, with Chinese scientists adding more than 1,000 accessions to the CIMMYT gene bank. CIMMYT maize varieties have been planted on more than 1 million hectares in China, with the partnership responsible for the release of 13 commercial varieties.

Renjian and Chinese dignitaries tour CIMMYT’s museum. (Photo: CIMMYT)

In 2023, the Joint Wheat Molecular Breeding International Lab (Joint Lab) launched as a collaborative project between China, Pakistan, and CIMMYT, with the aim of developing new high yield wheat varieties and enhancing capacity for crop breeding and production.

More recently, scientists have played an important role in the free exchange of germplasm between China and countries in Africa, which will help to mitigate against any gene pool loss caused by climate-induced extreme weather events and enable the development of more resilient crop varieties.

Tang said, “Witnessing first-hand the work of CIMMYT’s scientists in Mexico is inspiring. We look forward to exploring further how we can build on the excellent relationship between China and CIMMYT to address global agricultural challenges.”

Govaerts said, “We hope that this partnership continues in order to address the need for nutritious crops and to develop innovative solutions for smallholder farmers.”

Market segmentation and Target Product Profiles (TPPs): developing and delivering impactful products for farming communities

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

Experimental maize field. (Photo: CIMMYT)

With the ever-changing climate conditions, including the unpredictable El Niño, and dynamic changes in government policies, understanding farmers’ preferences and market segmentation has become crucial for implementing impactful breeding programs. Market segmentation is a strategic process which divides a market into distinct group of consumers with similar needs, preferences, and behaviors. This allows organizations to tailor their products and services to specific customer segments, thus ensuring maximum value and impact.

In today’s fast-paced and evolving agricultural landscape, market segmentation plays a vital role in helping organizations navigate the complexities of a dynamic market. CIMMYT’s maize breeding program has a successful track record in developing and delivering improved varieties that are climate-resilient, high-yielding and suited to the rainfed tropical conditions in Africa. To further strengthen the impact, it is important to have a clear understanding of the evolving needs of farmers in different agroecological regions and the emerging market scenario so that breeding processes can be tailored based on market needs and client requirements.

Questions arise on how to refine the breeding programs relative to country-specific market segments, what efforts are underway to target these markets, and how do these markets transition. Recognizing the importance of market segmentation in refining breeding programs at the country and regional levels, CIMMYT hosted two workshops on maize market intelligence in Kenya and Zimbabwe, under the CGIAR Market Intelligence Initiative for eastern and southern Africa.

“Market intelligence in breeding programs is critical to understand the evolving needs of key stakeholders, including farmers, consumers, and the seed industry. It helps continuously improve the breeding pipelines to develop and deliver impactful products in targeted market segments. The workshops brought together relevant experts from the national programs and seed companies for focused discussions to develop a harmonized breeding strategy. This would help to address the needs of smallholder maize farmers in eastern and southern Africa,” said Director of CIMMYT’s Global Maize program and One CGIAR Global Maize Breeding Lead, B.M. Prasanna.

B.M. Prasanna delivers a presentation. (Photo: CIMMYT)

The workshops constituted a strategic continuation of the Product Design Team (PDT) meetings under CGIAR Market Intelligence, with a focus on the refinement of gender-intentional target product profile design. Guided by the expertise of CIMMYT’s Global Maize program, Market Intelligence, and ABI-Maize Transform teams, the sessions saw active participation from key stakeholders including lead breeders, seed systems experts, and market specialists from the National Agricultural Research and Extension Systems (NARES), alongside collaborative engagement with seed company partners. The workshops underscored the commitment to incorporate diverse perspectives, aligning with the evolving maize market landscape in eastern and southern Africa.

“The workshop provided critical insights on opportunities to improve market penetration of improved maize varieties. There is a need to strike a balance between the needs of the farmers, seed industry, and consumers in variety development; actively involve farmers and consumers in variety selection and understanding their preferences; and focus on emerging needs of the market such as yellow maize for feed and food,” said James Karanja, maize breeding lead at the Kenya Agriculture & Livestock Research Organization, Kenya.

Insights from both workshops underscored the importance of providing breeders with pertinent information and comprehensive training. The discussions illustrated the necessity for breeders to define their objectives with a 360-degree outlook, aligning breeding programs with market segments and interfacing with CIMMYT’s regional vision.

Workshop participants. (Photo: CIMMYT)

“The market intelligence workshop is an excellent initiative for the breeding programs. It shows how traits can be identified and prioritized, based on farmers’ requirements. The maize value chain is broad, and the synergy between the developer of the product (breeder), the producer (farmer), and the consumer needs to be effective. Hence, streamlining of the market segments and eventually the target product profiles is key in ensuring that the breeders develop improved products/varieties with relevant traits that address the needs of farmers, consumers, and the seed industry,” said Lubasi Sinyinda, breeder from the Zambia Agricultural Research Institute, Zambia.

Another participant, Lucia Ndlala, a maize breeder at the Agricultural Research Council, South Africa, echoed similar enthusiasm. “The workshop was exceptionally informative, providing valuable insights into target product profiles and market segments. This knowledge will undoubtedly prove instrumental in shaping future breeding strategies,” she said.

When applied through a breeding lens, market segmentation is a vital tool in refining breeding programs at both country and regional levels, enabling breeders to better understand and address the diverse needs of the farmers, and ensuring that the improved varieties are tailored to market segments.

Examining how insects spread toxic fungi

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

Maize grain heavily damaged by the larger grain borer and maize weevil. (Photo: Jessica González/CIMMYT)

According to the World Health Organization (WHO), 10% of the global population suffers from food poisoning each year. Aflatoxins, the main contributor to food poisoning around the world, contaminate cereals and nuts and humans, especially vulnerable groups like the young, elderly, or immune-compromised, and animals are susceptible to their toxic and potentially carcinogenic effects.

Fungi contamination occurs all along the production cycle, during and after harvest, so the mitigation of the mycotoxins challenge requires the use of an integrated approach, including the selection of farmer-preferred tolerant varieties, implementing good agricultural practices such as crop rotation or nitrogen management, reducing crop stress, managing pests and diseases, biological control of mycotoxigenic strains, and good post-harvest practices.

Monitoring of mycotoxins in food crops is important to identify places and sources of infestations as well as implementing effective agricultural practices and other corrective measures that can prevent outbreaks.

A bug problem

Insects can directly or indirectly contribute to the spread of fungi and the subsequent production of mycotoxins. Many insects associated with maize plants before and after harvest act as a vector by carrying fungal spores from one location to another.

International collaboration is key to managing the risks associated with the spread of invasive pests and preventing crop damage caused by the newly introduced pests. CIMMYT, through CGIAR’s Plant Health initiative, partners with the Center for Grain and Animal Health Research of the US Department of Agriculture (USDA) and Kansas State University are investigating the microbes associated with the maize weevil and the larger grain borer.

The experiment consisted of trapping insects in three different habitats, a prairie near CIMMYT facilities in El Batán, Texcoco, Mexico, a maize field, and a maize store at CIMMYT’s experimental station at El Batán, using Lindgren funnel traps and pheromones lures.

Hanging of the Lindgren funnel traps in a prairie near El Bátan, Texcoco, Mexico. (Photo: Jessica González/CIMMYT)

Preliminary results of this study were presented by Hannah Quellhorst from the Department of Entomology at Kansas State University during an online seminar hosted by CIMMYT.

The collected insect samples were cultured in agar to identify the microbial community associated with them. Two invasive pests, the larger grain bore and the maize weevil, a potent carcinogenic mycotoxin was identified and associated with the larger grain borer and the maize weevil.

The larger grain borer is an invasive pest, which can cause extensive damage and even bore through packaging materials, including plastics. It is native to Mexico and Central America but was introduced in Africa and has spread to tropical and subtropical regions around the world. Together with the maize weevil, post-harvest losses of up to 60% have been recorded in Mexico from these pests.

“With climate change and global warming, there are risks of these pests shifting their habitats to areas where they are not currently present like sub-Saharan Africa and North Africa,” said Quelhorst. “However, the monitoring of the movement of these pests at an international level is lacking and the microbial communities moving with these post-harvest insects are not well investigated.”

Combatting maize lethal necrosis in Zimbabwe

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

Maize is a staple crop in Zimbabwe, playing a vital role in the country’s agricultural landscape as food for its own people and an export good. However, behind every successful maize harvest lies the quality of seed and resistance to diseases and stresses.

Amidst the multitude of diseases that threaten maize crops, one adversary is maize lethal necrosis (MLN). Though not native to Zimbabwe, it is crucial to remain prepared for its potential impact on food security.

What is maize lethal necrosis?

MLN is a viral disease, caused by a combination of two virus diseases. The disease emerged in Kenya in 2011 and quickly spread to other countries in eastern Africa. The introduction of MLN to Africa was likely affected by the movement of infected seed and insect vectors. MLN has had a severe impact on regional maize production, leading to yield losses of up to 90%.

Recognizing the need to equip seasoned practitioners with the knowledge and skills to effectively diagnose and manage MLN, CIMMYT organized a comprehensive training on MLN diagnosis and management, targeting 25 representatives from Zimbabwe’s Plant Quarantine Services.

From students to experienced technicians, pathologists and plant health inspectors, this was an opportunity to refresh their knowledge base or an introduction to the important work of MLN mitigation. “This training for both advanced level practitioners and students is crucial not only for building competence on MLN but also to refresh minds to keep abreast and be prepared with approaches to tackle the disease once it is identified in the country,” said Nhamo Mudada, head of Plant Quarantine Services.

Maize plants showing maize lethal necrosis (MLN). (Photo: CIMMYT)

Expectations were diverse, ranging from sharpening understanding of key signs and symptoms to learning from country case examples currently ridden with the disease. With CIMMYT’s guidance, practitioners learned how to identify MLN infected plants, make accurate diagnoses, and implement management strategies to minimize losses.

“For over 10 years, these trainings have been important to raise awareness, keep local based practitioners up to speed, help them diagnose MLN, and make sure that they practice proper steps to tackle this disease,” said L.M Suresh, CIMMYT maize pathologist and head of the MLN screening facility in Kenya.

Identifying the specific MLN causing viral disease affecting a maize plant is the first step in combating MLN. Determining whether it is a biotic or abiotic disease is critical in establishing its cause and subsequent diagnosis. By implementing proper diagnostic techniques and understanding the fundamentals of good diagnosis, practitioners can bring representative samples to the lab and accurately identify MLN.

Tackling MLN in Zimbabwe

Initiated in 2015 at Mazowe as a joint initiative between the Government of Zimbabwe and CIMMYT, a modern quarantine facility was built to safely import maize breeding materials from eastern Africa to southern Africa and enable local institutions to proactively breed for resistance against MLN.

The MLN quarantine facility at the Plant Quarantine Institute is run by the Department of Research and Specialist Services (DRSS) and is mandated to screen maize varieties imported under strict quarantine conditions to ensure that they are MLN-free.

Training participants pose outside of the MLN screening facilities. (Photo: CIMMYT)

To date, CIMMYT and partners have released 22 MLN resistant and tolerant hybrids in eastern Africa. CIMMYT’s research and efforts to combat MLN have focused on a multidimensional approach, including breeding for resistant varieties, promoting integrated pest management strategies, strengthening seed systems, and enhancing the capacity of farmers and stakeholders.

“Support extended through valuable partnerships between CIMMYT, and the collaborations have played a pivotal role from surveillance to diagnostics and building capacity,” said Mudada.

Feedback and insights

Chief Plant Health Inspector for Export and Imports Biosecurity, Monica Mabika, expressed gratitude for the training. “It is always an honor when we have expert pathologists come through and provide a valuable refresher experience, strengthening our understanding on issues around biosecurity and learning what other countries are doing to articulate MLN,” she said.

Students learn how to screen maize plants for MLN. (Photo: CIMMYT)

Among the students was Audrey Dohwera from the University of Zimbabwe, who acknowledged the importance of the training. “I have been attached for 2 months under the pathology department, and I was eager to learn about MLN, how to detect signs and symptoms on maize, how to address it and be able to share with fellow farmers in my rural community,” she said.

With the knowledge gained from this training, practitioners are well equipped to face the challenges that MLN may present, ultimately safeguarding the country’s maize production status.

How CGIAR maize breeding is improving the world’s major staple crop for tropical regions

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

Maize production is surging due to its diversified end uses. While it is already the first staple cereal globally, it is expected to emerge as the world’s predominant crop for cultivation and trade in the coming decade. Globally, it serves primarily as animal feed, but it is also a vital food crop, particularly in sub-Saharan Africa, Latin America, and in some areas in Asia. 

Climate change is, however, altering the conditions for maize cultivation, especially in the rainfed, stress-prone tropics. Abiotic stresses like heat, drought, and floods, as well as biotic threats such as diseases and insect pests are becoming more frequent. These have a disproportionate impact on the resource-constrained smallholders who depend on maize for their food, income, and livelihoods. 

In a race against time, crop breeders are working to enhance maize’s resilience to the changing climates. Among others, CIMMYT and the International Institute of Tropical Agriculture (IITA), working within CGIAR’s Accelerated Breeding Initiative, are utilizing breeding innovations to develop climate-resilient and nutritionally enriched maize varieties needed by the most vulnerable farmers and consumers.  

Better processes

Improving maize yields in the rainfed, stress-prone tropics is challenging. Nevertheless, CGIAR’s efforts have significant impacts, as breeding programs embraced continuous improvement and enhanced efficiency over the years.  

To increase genetic gains, CIMMYT maize breeding program implemented a systematic continuous improvement plan. Sixty percent of CIMMYT’s maize lines in Eastern and Southern Africa (ESA) are now developed through technologies that speed up breeding cycle and improve selection intensity and accuracy; these include doubled haploid technology, high-throughput phenotyping, molecular marker-assisted forward breeding, and genomic selection. The breeding cycle time has been reduced from five or six years to only four years in most of the maize product profiles. Product advancement decisions now incorporate selection indexes, and specialized software aid in the selection of parental lines for new breeding starts. 

CIMMYT and IITA maize teams are working together to investigate several key traits in maize for discovery, validation, and deployment of molecular markers. CGIAR maize team developed a framework for implementing a stage-gate advancement process for marker-trait pipeline, which enables informed decision-making and data-driven advancements at multiple stages, from marker-trait discovery proposal to marker discovery, validation, and deployment. Consolidating research efforts and implementing this process is expected to increase efficiency and collaboration in maize breeding programs.

An example of maize biotic stress exacerbated by climate change: fall armyworm (FAW) larvae, highly destructive pests, emerge out from an egg mass placed on a maize leaf. (Photo: A. Cortés/CIMMYT)

At the end of the breeding process, breeders must ensure the quality assurance and quality control (QA/QC) of the parental lines of the new varieties. Seed quality, which includes genetic purity, genetic identity, and verification of parentage – is critical in maize breeding and commercial seed production.  

CIMMYT has worked to enhance the capacity of NARES and seed company partners in Eastern and South Africa (ESA), Asia, and Latin America, in utilizing molecular markers for QA/QC in breeding and commercial seed production. This has resulted in more reliable and accurate outcomes. In addition, webinars and user-friendly software have boosted results for NARES maize breeders, regulatory agencies, and seed companies. These combined efforts mean a dependable, cost-effective, and efficient QA/QC system for the maize seed value chain in the Global South. 

Better tools 

With traditional means, obtaining a genetically homozygous or true-to-type maize line requires six to eight generations of inbreeding, and thus, more than ten years for developing a new hybrid. The technique of doubled haploid (DH), which enables derivation of 100% genetically homozygous lines in just two generations, is now integral to modern maize breeding. CIMMYT has pioneered the development of tropical maize DH technology, by developing and disseminating tropicalized haploid inducers, establishing centralized DH facilities in Mexico, Kenya and India, and providing DH development service to partners.  

Regional on-farm trials (ROFTs) is a crucial step in maximizing the impact of breeding investments. ROFTs help scientists understand performance of the pipeline hybrids under diverse farmers’ management conditions, besides environment, soil variability, etc. 

In ESA, ROFT networks for maize are expanded significantly over the last few years, from 20-30 sites per product profile to up to 300 sites, encompassing a wide range of smallholder farming practices. The experimental design was simplified to use less germplasm entries to be tested per farm, making it easier for the farmers to participate in the network, while improving data quality. Collaboration with NARES, seed companies, NGOs, and development partners was significantly stepped up to capture the social diversity within the target market segments. Gender inclusion was prioritized.

Training workshop organized by CIMMYT at the Maize Doubled Haploid Facility in Kunigal, India. (Photo: CIMMYT)

Strengthening the capacity of NARES and SMEs to systematically access and utilize improved maize germplasm is critical for increasing genetic gains in the stress-prone tropics. But partner institutions are at different stages of evolution, which means capacity strengthening must be tailored to institutional strengths and constraints.  

Accelerated Breeding has been strengthening regional CGIAR-NARES-SME collaborative maize breeding networks via activities such as exchanging elite tropical germplasm (inbred lines, trait donors, and breeding populations) through field days, and widely disseminating CIMMYT maize lines (CMLs) requested by institutions globally.  

Partners participate in CGIAR maize stage-advancement meetings – they are given access to multi-location trial data and participate in the selection process of promising hybrids to be advanced from the different breeding stages. CGIAR maize teams also assessed the capacity of different NARES institutions, and formulated continuous improvement plans in consultation with respective NARES teams for further support.  

Better varieties

Systematic integration of new breeding techniques and innovations in CGIAR maize breeding pipelines are leading to better varieties, at a much faster pace, and at lower cost. Given the impacts of climate change, this is indeed the need of the hour.  

Maize breeders need to respond rapidly to emerging and highly destructive insect-pests and diseases. For instance, the invasion of fall armyworm (FAW) in Africa (since 2016) and Asia (since 2018) has ravaged maize crops across more than 60 countries. CGIAR maize team in Africa responded to this challenge and made progress in identifying diverse sources of native genetic resistance to FAW, resulting in elite hybrids and open-pollinated varieties (OPVs) adapted to African conditions. 

Since 2017, CIMMY has strengthened the maize insectary capacity of KALRO-Katumani by optimizing the FAW mass rearing protocol and screening of maize germplasm under FAW artificial infestation at Kiboko Station, Kenya. The station now has sixteen 1,000m net houses. The intensive work since 2018 led to identification of FAW-tolerant inbred lines by CIMMYT and their distribution to over 90 public and private institutions in 34 countries. 

NARES partners across 13 countries in Africa have undertaken national performance trials of three FAW-tolerant hybrids developed by CIMMYT. Kenya, Zambia, Malawi, South Sudan and Ghana released the three hybrids in 2022-23, while several more countries are expected to release these hybrids in the coming months.

Drought and heat tolerant maize ears are harvested through a CIMMYT project. (Photo: J.Siamachira/CIMMYT)

Climate change is also exacerbating maize diseases. Affecting at least 17 countries in the Americas, the Tar Spot Complex (TSC) disease affects maize in the cool and humid regions. It causes premature leaf death, weakens plants, and reduces yields by up to 50%. CIMMYT maize team in Mexico has mapped genomic regions conferring TSC resistance, and is using these markers in breeding programs.  

The Global South is also particularly vulnerable to drought and high temperature stresses. In the past five years, 20 drought- and heat-tolerant maize hybrids have been released in Asia, including Bangladesh, Bhutan, India, Nepal, and Pakistan. Socio-economic studies in India and Nepal showed that farmers who adopted these hybrids realized higher grain yields, and increased income compared to the non-adopters. 

In 2022, certified seed production of CGIAR multiple stress-tolerant maize varieties reached 181,119 metric tons in sub-Saharan Africa (from 72,337 tons in 2016). This is estimated to cover ~7.4 million hectares, benefiting over 46 million people in 13 countries. 

With maize facing unprecedented threats from climate change-induced stresses in the rainfed stress-prone tropics, CGIAR maize breeding programs working closely with NARES and private sector have demonstrated remarkable success in breeding as well as deploying climate resilient maize.  These efforts rely on better processes and modern breeding tools, leading to drastically reduced breeding cycle time, cost saving, and improved efficiency.  

The resulting improved varieties–resilient to major environmental stresses, diseases and insect-pests–are increasingly adopted by smallholders across sub-Saharan Africa, South Asia, and Latin America, showing that tomorrow is already here. The work continues to ensure that maize remains a constant source of food security and prosperity for generations to come in the tropical regions.

Three new CIMMYT maize hybrids available from Southern Africa Breeding Program

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

CIMMYT is happy to announce three new, improved tropical maize hybrids that are now available for uptake by public and private sector partners, especially those interested in marketing or disseminating hybrid maize seed across southern Africa and similar agroecologies in other regions. NARES and seed companies are hereby invited to apply for licenses to pursue national release, scale-up seed production and deliver these maize hybrids to farming communities.

Newly available CIMMYT hybrids Key traits
CIM22SAPP1-15 Intermediate-maturing, white, high yielding, drought tolerant, NUE, and resistant to GLS, TLB, Ear rots, and MSV
CIM22SAPP1-12 Late maturing, white, high yielding, drought tolerant, low-nitrogen tolerant, and resistant to MSV, TLB, and Ear rots
CIM22SAPP2-10 Extra-early to early-maturing, white, high-yielding, drought tolerant, NUE, resistant to GLS, MSV, TLB

 

Performance data Download the CIMMYT Southern Africa Maize Regional On-Station (Stage 4) and On-Farm (Stage 5) Trials: Results of the 2022 and 2023 Seasons and Product Announcement from Dataverse.
How to apply Visit CIMMYT’s maize product allocation page for details
Application deadline The deadline to submit applications to be considered during the first round of allocations is January 26, 2024. Applications received after that deadline will be considered during subsequent rounds of product allocations.

 

The newly available CIMMYT maize hybrids were identified through rigorous, years-long trialing and a stage-gate advancement process which culminated in the southern Africa Stage 5 On Farm Trials. The products were found to meet the stringent performance and farmer acceptance criteria for CIMMYT’s breeding pipelines that are designed to generate products tailored for smallholder farmers in stress-prone agroecologies of southern Africa.

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 regarding the application process may be addressed to GMP-CIMMYT@cgiar.org with attention to Pamela Sithole, project coordinator, Global Maize Program, CIMMYT office in Zimbabwe.

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

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

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

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

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

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

Maize DH facility

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

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

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

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

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

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

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

MLN screening facility

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

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

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

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

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

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

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

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

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

Five new CIMMYT maize hybrids available from the Latin America breeding program

Written by mcallejas on . Posted in News.

CIMMYT is happy to announce five new, improved tropical and subtropical maize hybrids that are now available for uptake by public and private sector partners, especially those interested in marketing or disseminating hybrid maize seed across Latin America and similar agro-ecologies in other regions. NARES and seed companies are hereby invited to apply for licenses to pursue national release, scale-up seed production, and deliver these maize hybrids to farming communities.

How does CIMMYT’s improved maize get to the farmer?
Newly available CIMMYT hybrids Key traits Target Agro-ecology
CIM21LAPP1A-12 Intermediate maturing, white, high yielding, and resistant to TSC, MLB, and Ear rots Lowland tropics
CIM21LAPP1C-10 Intermediate maturing, yellow, high yielding, and resistant to TSC, MLB and Ear rots
CIM21LAPP2A-4 Intermediate-maturing, white, high-yielding, FSR, GLS, and Ear rots. Mid-altitudes/

Spring-Summer season
CIM21LAPP2A-8
CIM20LAPP2B-12 Intermediate-maturing, yellow, high-yielding, resistant to GLS, and Ear rots.

 

The newly available CIMMYT maize hybrids were identified through rigorous, years-long trialing and a stage-gate advancement process which culminated in the 03-22LTHTWM4M, 04-22LTHTYM4M, 01-22MASTCHSTW and 02-22MASTCHSTY Stage 5 Trials. The products were found to meet the stringent performance and farmer acceptance criteria for CIMMYT’s breeding pipelines that are designed to generate products tailored in particular for smallholder farmers in stress-prone agroecologies of Latin America.

Performance data Download the CIMMYT LATAM Maize Regional (Stage 4) and On-Farm (Stage 5) Trials: Results of the 2020 -2021 and 2022 Seasons and Product Announcement from Dataverse.
How to apply Visit CIMMYT’s maize product allocation page for details
Application deadline The deadline to submit applications to be considered during the first round of allocations is December 1st, 2023. Applications received after that deadline will be considered during subsequent rounds of product allocations.

 

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 Debora Escandón, Project Administrator, Global Maize Program, CIMMYT.

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Building capacities for advanced modern breeding programs in Africa

Written by Susan Otieno on . Posted in News.

In December 2022, more than 40 scientists from African National Agricultural Research Institutes (NARI) and Small and Medium Enterprise (SME) seed companies received training on the design and implementation of modern maize breeding programs.

The training, explains Yoseph Beyene, project leader in the Accelerating Genetic Gains (AGG) – Maize project, was designed to improve maize breeders’ knowledge of the most advanced technologies and methodologies in order to increase genetic gains in their respective breeding programs. It was supported by AGG-Maize and the CGIAR Accelerated Breeding Initiative (ABI) and formed part of ongoing efforts to modernize NARI breeding programs under AGG-Maize.

Yoseph Beyene, Accelerating Genetic Gains-Maize Project leader, makes introductory remarks at the start of the Senior Breeders Training in Nairobi, Kenya. (Photo: Susan Otieno/CIMMYT)

Over the course of five days in Nairobi, Kenya, participants from 13 countries where AGG-Maize is implemented worked to develop their skills in the use of new technologies and approaches to improving genetic gains and breeding efficiencies. Topics covered included the prioritization of market segmentation and product profile development, application of quantitative genetics principles in maize breeding, seed production research, improved designs for regional on-farm trials, and much more.

“The training was an eye opener supported by detailed explanations on applications of diverse research methodologies in maize breeding,” said Isiah Aleri, a research assistant for the International Maize and Wheat Improvement Center’s (CIMMYT) Maize Program in Kenya. “I met teams who had different views on some breeding techniques, but later received guided explanations from trainers on why certain standards and requirements are set for effective decision making.”

Veronica Ogugo, a research associate in the same CIMMYT program, agreed saying: “It was very educative and in-depth in all the areas that were covered by the different specialists. The best part was that each of the components complimented one another.” She added that the training also offered a good opportunity for interaction with other experts.

B.M. Prasanna, CIMMYT Global Maize Program director, speaks at the Senior Breeders Training in Nairobi, Kenya. (Photo: Susan Otieno/CIMMYT)

What and whom to breed for

In his opening remarks at the training, B.M. Prasanna, Global Maize Program director at CIMMYT, noted the need for efficient use of limited resources, and encouraged scientists to work smartly, for instance, by leveraging available germplasm across phenotyping networks from other regions to diversify germplasm base for increased genetic gains. He emphasized the importance of clearly determining market segments and developing product profiles that have clear objectives, as well as the key traits to be considered, such as tolerance to drought, heat, and pests and diseases like fall armyworm.

Prasanna highlighted zinc as an example of an important feature to focus on, pointing out the micronutrient’s vital role in mental well-being and its immune boosting properties, especially in children. “Different geographies have different ways of using maize,” he explained. “In general, maize provides 15-56% of total calorie intake in the rain-fed tropics, hence its importance for improving not only smallholder farmer incomes but also food and nutrition security.”

He also outlined how important partnerships with national programs and seed companies are for achieving the fullest impact of CIMMYT’s work. “The strong regional collaborative maize breeding and seed systems is fundamental for impact,” he said. “It is also the reason for arguably the largest public sector maize germplasm testing network in the Global South, in rain-fed stress-prone tropical environments.”

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

Six New CIMMYT maize hybrids available from eastern Africa Breeding Program

Written by Leslie Domínguez on . Posted in News.

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

CIMMYT is happy to announce six new, improved tropical maize hybrids that are now available for uptake by public and private sector partners, especially those interested in marketing or disseminating hybrid maize seed across eastern Africa and similar agro-ecologies in other regions. NARES and seed companies are hereby invited to apply for licenses to pursue national release, scale-up seed production, and deliver these maize hybrids to farming communities.

 

Newly available CIMMYT hybrids Key traits
CIM21EAPP1-01-23 Intermediate maturing, white, high yielding, drought tolerant, NUE, and resistant to GLS, TLB, Ear rots, and MSV
CIM21EAPP1-01-22
CIM21EAPP1-02-13 Early maturing, white, high yielding, drought tolerant, NUE, and resistant to GLS, TLB, Ear rots, and MLN
CIM21EAPP1-02-11
CIM21EAPP2-01 Late maturing, white, high yielding, drought tolerant, NUE, and resistant to GLS, TLB, Ear rots, and Striga
CIM21EAPP2-05

 

Performance data Download the CIMMYT Eastern Africa Maize Regional On-Station (Stage 4) and On-Farm (Stage 5) Trials: Results of the 2021 to 2022 Seasons and Product Announcement from Dataverse.
How to apply Visit CIMMYT’s maize product allocation page for details
Application deadline The deadline to submit applications to be considered during the first round of allocations is 21 May 2023. Applications received after that deadline will be considered during subsequent rounds of product allocations.

 

The newly available CIMMYT maize hybrids were identified through rigorous, years-long trialing and a stage-gate advancement process which culminated in the 2022 Eastern Africa On-Farm (Stage 5) Trials. The products were found to meet the stringent performance and farmer acceptance criteria for CIMMYT’s breeding pipelines that are designed to generate products tailored in particular for smallholder farmers in stress-prone agroecologies of eastern Africa .

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