Written by Bea Ciordia on . Posted in Uncategorized.
MARPLE (Mobile And Real-time PLant disEase) diagnostics is a new innovative approach for fungal crop pathogen diagnostics developed by Diane Saundersâs team at the John Innes Centre.
MARPLE is the first operational system in the world using nanopore sequencing for rapid diagnostics and surveillance of complex fungal pathogens in situ. Generating results in 48 hours of field sampling, this new digital diagnostic strategy is leading revolutionary changes in plant disease diagnostics. Rapid strain level diagnostics are essential to quickly find new emergent strains and guide appropriate control measures.
Through this project, CIMMYT will:
Deploy and scale MARPLE to priority geographies and diseases as part of the Current and Emerging Threats to Crops Innovation Lab led by Penn State University / PlantVillage and funded by USAID’s Feed the Future.
Build national partner capacity for advanced disease diagnostics. We will focus geographically on Ethiopia, Kenya and Nepal for deployment of wheat stripe and stem rust diagnostics, with possible expansion to Bangladesh and Zambia (wheat blast).
Integrate this new in-country diagnostic capacity with recently developed disease forecasting models and early warning systems. Already functional for wheat stripe rust, the project plans to expand MARPLE to incorporate wheat stem rust and wheat blast.
Written by Bea Ciordia on . Posted in Uncategorized.
The Bangladesh Integrated Pest Management Activity (IPMA) project aims to strengthen the capacity of agricultural stakeholders in Bangladesh by controlling and preventing the spread of current and emerging threats to ensure more efficient, profitable, and environmentally safe agricultural production and productivity.
Objectives
Increase the availability and affordability of integrated pest management measures for the prevention and spread of current and emerging threats
Strengthen the capacity of Bangladesh agricultural stakeholders, such as academia, financial institutions, government, judiciary, media, civil society, the private sector, and value chain actors, to implement integrated pest management measures
Enhance the adoption of integrated pest management by smallholder farmers to increase agricultural production and productivity, while reducing environmental hazards caused by indiscriminate use of pesticides
Spot blotch, a major biotic stress challenging bread wheat production is caused by the fungus Bipolaris sorokiniana. In a new study, scientists from the International Maize and Wheat Improvement Center (CIMMYT) evaluate genomic and index-based selection to select for spot blotch resistance quickly and accurately in wheat lines. The former approach facilitates selecting for spot blotch resistance, and the latter for spot blotch resistance, heading and plant height.
Genomic selection
The authors leveraged genotyping data and extensive spot blotch phenotyping data from Mexico and collaborating partners in Bangladesh and India to evaluate genomic selection, which is a promising genomic breeding strategy for spot blotch resistance. Using genomic selection for selecting lines that have not been phenotyped can reduce the breeding cycle time and cost, increase the selection intensity, and subsequently increase the rate of genetic gain.
Two scenarios were tested for predicting spot blotch: fixed effects model (less than 100 molecular markers associated with spot blotch) and genomic prediction (over 7,000 markers across the wheat genome). The clear winner was genomic prediction which was on average 177.6% more accurate than the fixed effects model, as spot blotch resistance in advanced CIMMYT wheat breeding lines is controlled by many genes of small effects.
âThis finding applies to other spot blotch resistant loci too, as very few of them have shown big effects, and the advantage of genomic prediction over the fixed effects model is tremendousâ, confirmed Xinyao He, Wheat Pathologist and Geneticist at CIMMYT.
The authors have also evaluated genomic prediction in different populations, including breeding lines and sister lines that share one or two parents.
Spot blotch susceptible wheat lines (left) and resistant lines. (Photo: Xinyao He and Pawan Singh/CIMMYT)
Index selection
One of the key problems faced by wheat breeders in selecting for spot blotch resistance is identifying lines that are genetically resistant to spot blotch versus those that escape and exhibit less disease by being late and tall. âThe latter, unfortunately, is often the case in South Asiaâ, explained Pawan Singh, Head of Wheat Pathology at CIMMYT.
A potential solution to this problem is the use of selection indices that can make it easier for breeders to select individuals based on their ranking or predicted net genetic merit for multiple traits. Hence, this study reports the first successful evaluation of the linear phenotypic selection index and Eigen selection index method to simultaneously select for spot blotch resistance using the phenotype and genomic-estimated breeding values, heading and height.
This study demonstrates the prospects of integrating genomic selection and index-based selection with field based phenotypic selection for resistance in spot blotch in breeding programs.
Spot blotch, caused by the fungus Biopolaris sorokiniana poses a serious threat to bread wheat production in warm and humid wheat-growing regions globally, affecting more than 25 million hectares and resulting in huge yield losses.
Chemical control approaches, including seed treatment and fungicides, have provided acceptable spot blotch control. However, their use is unaffordable to resource-poor farmers and poses a hazard to health and the environment. In addition, âabiotic stresses like heat and drought that are widely prevalent in South Asia compound the problem, making varietal genetic resistance the last resort of farmers to combat this disease,â according to Pawan Singh, Head of Wheat Pathology at the International Maize and Wheat Improvement Center (CIMMYT). Therefore, one of CIMMYTâs wheat research focus areas is developing wheat varieties that carry genetic resistance to the disease.
Signs of spot blotch on wheat. (Photo: Philomin Juliana/CIMMYT)
The studyâs results are positive and confirmed that:
Many advanced CIMMYT breeding lines have moderate to high resistance to spot blotch.
Resistance to the disease is conferred quantitatively by several minor genomic regions that act together in an additive manner to confer resistance.
There is an association of the 2NS translocation from the wild species Aegilops ventricosa with spot blotch resistance.
There is also an association of the spot blotch favorable alleles at the 2NS translocation, and two markers on the telomeric end of chromosome 3BS with grain yield evaluated in multiple environments, implying that selection for favorable alleles at these markers could help obtain higher grain yield and spot blotch resistance.
âConsidering the persistent threat of spot blotch to resource-poor farmers in South Asia, further research and breeding efforts to improve genetic resistance to the disease, identify novel sources of resistance by screening different germplasm, and selecting for genomic regions with minor effects using selection tools like genomic selection is essential,â explained Philomin Juliana, Molecular Breeder and Quantitative Geneticist at CIMMYT.
Cover photo: Researchers evaluate wheat for spot blotch at CIMMYTâs experimental station in Agua FrĂa, Jiutepec, Morelos state, Mexico. (Photo: Xinyao He and Pawan Singh/CIMMYT)
Workshop participants stand for a group photo. (Photo: Danny Ward/John Innes Centre)
On April 26â29, 2022, researchers from Nepal participated in a workshop on the use of MARPLE Diagnostics, the most advanced genetic testing methodology for strain-level diagnostics of the deadly wheat yellow rust fungus. Scientists from the International Maize and Wheat Improvement Center (CIMMYT) and the John Innes Centre trained 21 researchers from the Nepal Agricultural Research Council (NARC) and one from iDE. The workshop took place at NARC’s National Plant Pathology Research Centre in Khumaltar, outside the capital Kathmandu.
âThe need for new diagnostic technologies like MARPLE and the critical timing of the workshop was highlighted by the severe yellow rust outbreak observed this season in the western areas of Nepal,â commented Dave Hodson, Senior Scientist at CIMMYT and project co-lead. âHaving national capacity to detect the increasing threats from yellow rust using MARPLE will be an important tool to help combat wheat rusts in Nepalâ.
The yellow rust fungus can cause grain yield losses of 30â80 % to wheat, Nepalâs third most important food crop.
Current diagnostic methods for wheat rust used in Nepal are slow, typically taking months between collecting the sample and final strain identification. They are also costly and reliant on sending samples overseas to highly specialized labs for analysis.
MARPLE (Mobile and Real-time PLant disEase) Diagnostics is the first method to place strain-level genetic diagnostics capability directly into the hands of Nepali researchers, generating data in-country in near-real time, for immediate integration into early warning systems and disease management decisions.
âThis is a fantastic opportunity to bring the latest innovations in plant disease diagnostics for the wheat rust pathogens to where they are needed most, in the hands of researchers in the field working tirelessly to combat these devastating diseases,â commented Diane Saunders, Group Leader at the John Innes Centre and project co-lead.
Diane Saunders (left), Group Leader at the John Innes Centre and project co-lead, observes workshop participants during the use of MARPLE. (Photo: Danny Ward/John Innes Centre)
Suraj Baidya senior scientist and chief of the National Plant Pathology Research Centre at NARC noted the worrying recent geographical expansion of yellow rust in Nepal. âDue to global warming, yellow rust has now moved into the plain and river basin area likely due to evolution of heat tolerant pathotypes. MARPLE Diagnostics now gives us the rapid diagnostics needed to help identify and manage these changes in the rust pathogen population diversity,â he said.
The highly innovative MARPLE Diagnostics approach uses the hand-held MinION nanopore sequencer, built by Oxford Nanopore, to generate genetic data to type strains of the yellow rust fungus directly from field samples.
Beyond MARPLE Diagnostics, Saunders noted that âthe workshop has also opened up exciting new possibilities for researchers in Nepal, by providing local genome-sequencing capacity that is currently absent.â
MARPLE (Mobile and Real-time PLant disEase) Diagnostics is a revolutionary mobile lab kit. It uses nanopore sequence technology to rapidly diagnose and monitor wheat rust in farmersâ fields. (Photo: Danny Ward/John Innes Centre)
Whatâs next for MARPLE Diagnostics in Nepal?
Following the successful workshop, Nepali researchers will be supported by CIMMYT and the John Innes Centre to undertake MARPLE Diagnostics on field samples collected by NARC. âThe current plan includes monitoring of yellow rust on the summer wheat crop planted at high hill areas and then early sampling in the 2022/23 wheat season,â Hodson noted.
âWe were struck by the enthusiasm and dedication of our colleagues to embrace the potential offered by MARPLE Diagnostics. Looking forward, we are excited to continue working with our Nepali colleagues towards our united goal of embedding this methodology in their national surveillance program for wheat rusts,â Saunders remarked.
MARPLE Diagnostics is supported by the Feed the Future Innovation Lab for Current and Emerging Threats to Crops, funded by the United States Agency for International Development (USAID), the UK Biotechnology and Biological Sciences Research Council (BBSRC) Innovator of the Year Award, the CGIAR Big Data Platform Inspire Challenge, the Bill & Melinda Gates Foundation and the United Kingdomâs Foreign, Commonwealth and Development Office.
For a decade, scientists at the International Maize and Wheat Improvement Center (CIMMYT) have been at the forefront of a multidisciplinary and multi-institutional effort to contain and effectively manage maize lethal necrosis (MLN) disease in Africa.
The manual is relevant to stakeholders in countries where MLN is already present, and also aims to offer technical tips to ââhigh-riskâ countries globally for proactive implementation of practices that can possibly prevent the incursion and spread of the disease,â writes B.M. Prasanna, director of CIMMYTâs Global Maize Program and MAIZE, in the foreword.
âWhile intensive multi-disciplinary and multi-institutional efforts over the past decade have helped in containing the spread and impact of MLN in sub-Saharan Africa, we cannot afford to be complacent. We need to continue our efforts to safeguard crops like maize from devastating diseases and insect-pests, and to protect the food security and livelihoods of millions of smallholders,â says Prasanna, who is presently leading the OneCGIAR Plant Health Initiative Design Team.
A new Bloomberg op-ed urges nations to steer more money to organizations like CIMMYT that are advancing crucial research on how to grow more resilient wheat and maize crops in regions that are becoming steadily less arable.
Together with the United States Agency for International Development (USAID) and Feed the Future, the International Maize and Wheat Improvement Center (CIMMYT) and the CGIAR Research Program on Maize (MAIZE) are pleased to announce the release of âFall Armyworm in Asia: A Guide for Integrated Pest Management.â
The publication builds on intensive, science-based responses to fall armyworm in Africa and Asia.
âI have encountered few pests as alarming as the fall armyworm,â wrote USAID Chief Scientist Rob Bertram in the guideâs Foreword. âThis publication … offers to a broad range of public and private stakeholders â including national plant protection, research and extension professionals â evidence-based approaches to sustainably manage fall armyworm,â Bertram adds.
âPartners from a wide array of national and international institutions have contributed to the mammoth task of formulating various chapters in the guide,â said B.M. Prasanna, director of CIMMYTâs Global Maize Program and of MAIZE. âWhile the publication is focused on Asia, it provides an updated understanding of various components of fall armyworm integrated pest management that could also benefit stakeholders in Africa.â
In January 2018, CIMMYT and USAID published a similar guide on integrated pest management of fall armyworm in Africa, which reached a large number of stakeholders globally and is widely cited. Prasanna spearheaded the development and publication of both guides.
âMy goal is to produce and sell 200 metric tons of hybrid maize by 2025,â says Subash Raj Upadhyaya, chairperson of Lumbini Seed Company, based in Nepalâs Rupandehi district.
Upadhyaya is one of the few seed value chain actors in the country progressing in the hybrid seed sector, which is at a budding stage in Nepal. He envisions a significant opportunity in the domestic production of hybrid maize seed varieties that not only offer a higher yield than open-pollinated varieties but will also reduce expensive imports. Leaping from one hectare to 25 hectares in hybrid maize seed production within three years, Upadhyaya is determined to expand the local seed market for hybrids.
Nepal has long been a net importer of hybrid seeds â mainly rice, maize and high-value vegetables â worth millions of dollars a year to meet the farmersâ demand, which is continuously rising. Although hybrid varieties have been released in the country, organized local seed production and marketing were not in place to deliver quality seeds to farmers. The hybrid variety development process is relatively slow due to lack of strong public-private relationships, absence of enabling policies and license requirements for the private sector to produce and sell them, lack of suitable germplasm and inadequate skilled human resources for hybrid product development and seed production. This has resulted in poor adoption of hybrid seeds, especially maize, where only 10-15% out of 950,000 hectares of Nepalâs maize-growing area is estimated to be covered with hybrid seeds, leaving the balance for seeds of open pollinated varieties.
This is where experts from the International Maize and Wheat Improvement Center (CIMMYT) have stepped in to unlock the untapped potential of domestic maize production and increase on-farm productivity, which is currently around 2.8 metric tons per hectare. Aligning with the goals of the National Seed Vision (NSV 2013-2025), the USAID-funded Nepal Seed and Fertilizer (NSAF) project, implemented by CIMMYT, fosters private sector involvement in the evaluation, production and marketing of quality hybrid seeds to meet the growing domestic demand for grain production, which is currently being met via imports. In 2020, Nepal spent nearly $130 million to import maize grain for the poultry industry.
A graphic shows the Nepal Seed and Fertilizer (NSAF) project’s innovations and intervention in hybrid seed. (Graphic: CIMMYT)
Teach a man to fish
Strengthening and scaling hybrid seed production of different crop varieties from domestic sources can be a game-changer for the long-term sustainability of Nepalâs seed industry.
Through the NSAF project, CIMMYT is working with eight partner seed companies and three farmers cooperatives to produce seeds of maize, rice and tomato. CIMMYT has played a vital role in making suitable germplasms and market-ready products of hybrids sourced from CGIAR centers available to the Nepal Agricultural Research Council (NARC) and partner seed companies for testing, validation and registration in the country. But this alone is not enough.
The project also carried out the partnersâ capacity building on research and development, parental line maintenance, on-station and on-farm demonstrations, quality seed production and seed quality control to equip them with the required skills for a viable and competitive hybrid seed business. The companies and farmer cooperatives received hands-on training on hybrid seed production and marketing coupled with close supervision and guidance by the projectâs field staff assigned to mentor and support individual seed companies. CIMMYTâs NSAF project also provides financial support to selected hybrid seed business startups to enhance their technical and entrepreneurial skills. This is a new feature, as prior to the project starting nearly all of the seed companies were mainly involved in aggregating open-pollinated variety seeds from farmers and selling them with no practical experience in the hybrid seed business.
In 2018, CIMMYT, through the NSAF and Heat Stress Tolerant Maize for Asia (HTMA) projects, and in close collaboration with NARCâs National Maize Research Program, engaged its partner seed company to initiate the first hybrid maize seed production during the winter season. Farmersâ feedback on the performance of the Rampur Hybrid-10 maize variety showed it could compete with existing commercial hybrids on yield and other commercial traits. As a result, this response boosted the confidence of seed companies and cooperatives to produce and market the hybrid seeds.
âI am very much motivated to be a hybrid maize seed producer for Lumbini Seed Company,â said a woman hybrid seed grower, whose income was 86% higher than the sale of maize grain from the previous season. âThis is my second year of engagement, and last year I got an income of NPR 75,000 (approx. USD$652) from a quarter of a hectare. Besides the guaranteed market I have under the contractual agreement with the company, the profit is far higher than what I used to get from grain production.â
To build the competitiveness of the local seed sector, CIMMYT has been mentoring partner seed companies on business plan development, brand building, marketing and promotion, and facilitating better access to finance. As part of the intervention, the companies are now selling hybrid seeds through agro-dealers in attractive and suitable product packages of varied sizes designed to help boost seed sales, better shelf life and compete with imported brands. They have also started using attractive seed packages for selected open-pollinated rice varieties in a bid to increase market demand. Prior to the projectâs intervention, companies used to sell their seeds in traditional unbranded jute bags which are less suitable to maintain seed quality.
AbduRahman Beshir, NSAF seed systems lead, gives an explanation on CIMMYTâs hybrid maize seed interventions during a field visit in Nepal. (Photo: CIMMYT)
Unite and conquer
Encouraging public-private partnerships for seed production is crucial for creating and maintaining a viable seed system. However, the existing guidelines and policies for variety registration are not private sector friendly, resulting in increased informal seed imports and difficulty to efficiently run a business. This draws attention to conducive policies and regulations patronage in research and varietal development, product registration, exclusive licensing, and seed production and marketing by the private sector.
CIMMYT supports the Seed Entrepreneurs Association of Nepal (SEAN), an umbrella body with more than 2,500 members, to promote the private sectorâs engagement in the seed industry and foster enabling policies essential to further unlock Nepalâs potential in local hybrid seed production and distribution. Together, CIMMYT and SEAN have facilitated various forums, including policy dialogues and elicitations on fast track provision of R&D license and variety registration by the local private seed companies. These are vital steps to realize the targets set by NSV for hybrid seed development and distribution.
To further enhance linkages among seed sector stakeholders and policy makers, CIMMYT, in coordination with NARCâs National Maize Research Program, organized a high-level joint monitoring field visit to observe hybrid maize seed production performance in April 2021. As part of the visit, Yogendra Kumar Karki, Secretary of the Ministry of Agriculture and Livestock Development, accompanied by representatives from the National Seed Board, National Planning Commission, Ministry of Finance, NARC, Seed Quality Control Center and SEAN, interacted with seed grower farmers and seed companies on their experiences.
The trip helped build a positive perception of the private sectorâs capability and commitment to contribute to Nepalâs journey on self-reliance on hybrid seeds. âThe recent advances in hybrid seed production by the private sector in collaboration with NARC and NSAF is astounding,â said Karki, as he acknowledged CIMMYTâs contribution to the seed sector development in Nepal. âConsidering the gaps and challenges identified during this visit, the Ministry will revisit the regulations that will help accelerate local hybrid seed production and achieve NSVâs target.â
In continued efforts, CIMMYT is also partnering with the governmentâs Prime Minister Agricultural Modernization Project (PMAMP) maize super zone in the Dang district of Nepal to commercialize domestic maize hybrid seed by partner seed companies. This will enable companies to invest in hybrid maize seed production with contract growers by leveraging the support provided by the PMAMP on irrigation, mechanization and maize drying facilities.
âOur interventions in seed systems integration and coordination are showing very promising results in helping Nepal to become self-reliant on hybrid maize seeds in the foreseeable future,â said AbduRahman Beshir, seed systems lead for the NSAF project. âThe initiative by the local seed companies to further engage and expand their hybrid seed business is an indication of a sustainable and viable project intervention. The project will continue working with both public and private partners to consolidate the gains and further build the competitiveness of the local seed companies in the hybrid maize seed ecosystem.â
Nepalâs seed industry is entering a new chapter that envisages a strong domestic seed sector in hybrid seed, particularly in maize, to capture a significant market share in the near future.
AbduRahman Beshir, CIMMYT seed systems lead, explains the stages of hybrid seed production to postgraduate students at a field trip in Rupandehi, Nepal. (Photo: Bandana Pradhan/CIMMYT)
Recently, a group of 40 postgraduate students from Nepalâs Agriculture and Forestry University (AFU) were able to learn first-hand about hybrid maize seed production in a field site managed by a partner seed company of the International Maize and Wheat Improvement Center (CIMMYT). Bringing in a whole new and rare experience altogether, the students got a glimpse of the progress and challenges of the seed industry as of today.
The field trip followed the development of a revised curriculum for AFUâs Seed Science and Technology program, initiated in November 2019, which stresses the importance of creating linkages between university students and private seed companies. Through the USAID-supported Nepal Seed and Fertilizer (NSAF) project, CIMMYT is working towards enhancing partnerships between agricultural universities and the seed industry, and revisiting the curriculum has been the first stepping stone.
In collaboration with AFU and Lumbini Seed Company, CIMMYT organized an off-campus participatory learning experience to enrich students’ understanding of hybrid seed production initiatives by the private sector and the opportunities that lie in the various business models of Nepalese seed companies. The initiative is part of a concerted effort by CIMMYT and its partners to alleviate the critical limitations of skilled manpower in the industry.
Subash Raj Upadhyaya, managing director of Lumbini Seed Company, shares his experience in hybrid seed production during the field visit. (Photo: Bandana Pradhan/CIMMYT)
A deep dive into hybrid seed
The program began with an on-site briefing on the recent developments of hybrid seed production by the private sector.
âNowadays, farmers are increasingly demanding hybrid seeds over open-pollinated varieties due to their higher yields,â explained Subash Raj Upadhyaya, Managing Director of Lumbini Seed Company. This seed demand is almost entirely met via imports.
Since 2018, the company has been successful in producing and marketing hybrid maize seed such as Rampur Hybrid-10, a variety originally sourced from CIMMYT and released in Nepal by the National Maize Research Program with technical and financial support from the NSAF project. Going from one hectare to 25 hectares of hybrid maize seed production in the course of three years, Lumbini Seed Company has demonstrated the capability of local private seed companies building up the countryâs capacity in this area.
âThe collaboration between public and private seed stakeholders is helping Nepal to realize hybrid seed self-reliance in the foreseeable future,â explained AbduRahman Beshir, seed systems lead for the NSAF project at CIMMYT. âWhat is needed is competitive products augmented by quality seed production and effective marketing strategies.â
Beshir described the important stages of seed production and the components of robust seed systems, while Hari Kumar Shrestha, a seed systems officer at CIMMYT, detailed the requirements for quality seed production and certification of hybrid seeds as per government guidelines in Nepal. Participating students were then able to practice detasseling and roughing off-type plants from a single row in a hybrid maize production field, under the guidance and supervision of the team from CIMMYT and the seed company.
This was followed by an interactive discussion with representatives from Lumbini about their activities, developments and limitations, and a tour of the companyâs seed processing, laboratory and storage for the group to observe the techniques used to produce, maintain and market quality seeds.
Postgraduate students observe the tassels of maize plants in Rupandehi, Nepal. (Photo: Bandana Pradhan/CIMMYT)
A nourishing experience
Applying the theoretical learnings of plant breeding and agronomy courses in a practical setting was an eye-opener for the postgraduates.
Student Sadhana Poudyal shared how the event had boosted her confidence in performing critical activities such as identifying the key features of pollen and seed parents. Now majoring in Seed Science and Technology, Poudyal previously worked with the Nepal Agriculture Research Council (NARC) and was granted a scholarship by CIMMYT, through the NSAF project, to begin a postgraduate program in 2019. âI was fascinated to learn about the remarkable progress made in hybrid seed production and I feel motivated to work in this sector in the future,â she said. Poudyal plans to use these learnings during her research into baby corn at NARC after completing her studies.
âI have always been keen on learning plant genetics and breeding as I foresee a good scope in this area,â said Lokendra Singh, another student at AFU. âThis trip was definitely insightful, and I thoroughly enjoyed receiving a practical lesson on the advantages and limitations of the various types of hybrids including single and three-way cross hybrids. Todayâs experience has doubled my enthusiasm to work as a plant breeder after my graduation.â
It is critical to engage students on the recent advances in seed science so that they are encouraged to pursue a career in agricultural research in Nepal. âOne of the major challenges is recruiting a workforce with critical skills and knowledge in the local seed industry since many students go abroad after they graduate,â said Upadhyaya. âWe look forward to partnering with agricultural universities for many similar on-site learnings.â
Educational experiences in the field, such as this, provide a better picture of the recent advancements and limitations in the seed sector which are usually not reflected in the textbooks. Creating a larger pool of skillful human resources, particularly in hybrid product development, improved seed production technologies and quality seed production, will not only help strengthen the local seed industry but also reduce the countryâs dependency on imports in the coming years.
Wheat stalks grow in a field in India. (Photo: Saad Akhtar)
For scientists, determining how best to increase wheat yields to meet food demand is a persistent challenge, particularly as the trend toward sustainably intensifying production on agricultural lands grows.
The United Nations projects that the current global population of 7.6 billion will increase to more than 9.8 billion by 2050, making higher grain yield potential vital, particularly as climate instability increases due to global warming. International efforts are also focused on meeting the Zero Hunger target detailed in the UN Sustainable Development Goals before they expire in 2030.
Now, a new landmark research survey on the grain yield potential and climate-resilience of bread wheat (Triticum aestivum L.) has brought scientists a few strides closer to meeting their ambitions.
Grain yield has traditionally been an elusive trait in genomic wheat breeding because of its quantitative genetic control, which means that it is controlled by many genomic regions with small effects.
Challenges also include a lack of good understanding about the genetic basis of grain yield, inconsistent grain yield quantitative trait loci identified in different environments, low heritability of grain yield across environments and environment interactions of grain yield.
To dissect the genetic architecture of wheat grain yield for the purposes of the research, which appeared in Scientific Reports, researchers implemented a large-scale genome-wide association study based on 100 datasets and 105,000 grain yield observations from 55,568 wheat breeding lines developed by the International Maize and Wheat Improvement Center (CIMMYT).
They evaluated the lines between 2003 and 2019 in different sites, years, planting systems, irrigation systems and abiotic stresses at CIMMYTâs primary yield testing site, the Norman E. Borlaug Experimental Research Station, Ciudad Obregon, Mexico, and in an additional eight countries â including Afghanistan, India and Myanmar â through partnerships with national programs.
The researchers also generated the grain-yield associated marker profiles and analyzed the grain-yield favorable allele frequencies for a large panel of 73,142 wheat lines, resulting in 44.5 million data points. The marker profiles indicated that the CIMMYT global wheat germplasm is rich in grain yield favorable alleles and is a trove for breeders to choose parents and design strategic crosses based on complementary grain yield alleles at desired loci.
âBy dissecting the genetic basis of the elusive grain-yield trait, the resources presented in our study provide great opportunities to accelerate genomic breeding for high-yielding and climate-resilient wheat varieties, which is a major objective of the Accelerating Genetic Gain in Maize and Wheat project,â said CIMMYT wheat breeder Philomin Juliana.
âThis study is unique and the largest-of-its-kind focusing on elucidating the genetic architecture of wheat grain yield,â she explained, âa highly complex and economically important trait that will have great implications on future diagnostic marker development, gene discovery, marker-assisted selection and genomic-breeding in wheat.â
Currently, crop breeding methods and agronomic management put annual productivity increases at 1.2% a year, but to ensure food security for future generations, productivity should be at 2.4% a year.
So, the extensive datasets and results presented in this study are expected to provide a framework for breeders to design effective strategies for mitigating the effects of climate change, while ensuring food-sustainability and security.
Protected from the harsh midday sun with a hat, Pramila Mondal pushes behind the roaring engine of a two-wheel tractor. She cultivates a small plot of land with her husband in the small village of Bara Kanaibila, in the Rajbari district of Bangladesh, near the capital Dhaka.
Using this machine, she also provides planting services to farmers who need to sow wheat, maize, mungbean, mustard and jute, earning her between $600 and $960 in each planting season.
Mondal and her husband first heard about this technology five years ago, when they attended an event to promote agricultural mechanization, organized by the International Maize and Wheat Improvement Center (CIMMYT). After seeing a demonstration, they were convinced that the power-tiller-operated seeder could form the basis for a business.
Ultimately, Mondal bought the machine. She got training on how to operate and maintain it, as part of the Cereal Systems Initiative for South Asia â Mechanization Irrigation and Mechanization Extension Activity (CSISA-MI and CSISA-MEA) project, supported by USAID through Feed the Future.
Letâs get it started
Pramila Mondal activates the self-starting mechanism on her power-tiller-operated seeder. (Photo: Shahabuddin Shihab/CIMMYT)
Mondal became the only woman in her area who could operate a seeder of this type, making her locally famous. After seeing the results of her business, others followed suit.
Eight more women in her area expressed interest in operating power-tiller-operated seeders and also went on to become service providers.
They all faced a similar problem: power tillers are hard to start. Pulling the starting rope or turning the hand crank requires a lot of strength.
The CSISA-MEA project team worked with a local engineering company to introduce a self-starting mechanism for power tiller engines. Since then, starting diesel engines is no longer a problem for women like Mondal.
Glee for the tillerwoman
Almost all of the 11 million hectares of rice planted every year in Bangladesh are transplanted by hand. It is becoming increasingly difficult to find people willing to do this type of backbreaking work. New machines are being introduced that transplant rice mechanically, but they require rice seedling to be raised in seedling mats.
As this new service is required, Mondal jumped at the opportunity. With support from CIMMYT through the CSISA-MEA project, she is now raising seedlings for this new type of rice transplanters.
CIMMYT facilitated training for machinery service providers on mat type seedling production, in partnership with private companies. Mondal and other women who were also trained produced enough seedlings to plant 3.2 hectares of land with a rice transplanter they hired from a local owner.
Mondal and her husband now have big dreams. They intend to buy a rice transplanter and a combine harvester.
âWith our effort we can make these changes, but a little support can make big difference, which the CSISA-MEA project did,â she said.
A seed vendor near Islamabad, Pakistan. For improved crop varieties to reach the farmers who need them, they usually must first reach local vendors, who form an essential link in the chain between researchers, seed producers and farmers. (Photo: M. DeFreese/CIMMYT)
Wheat is not just an essential part of the Pakistani diet, but also absolutely critical to the countryâs economy and to the farmers who cultivate it. The government of Pakistanâs goal to achieve self-sufficiency in wheat production just became more attainable with the release of five new wheat varieties. These new seeds could help the countryâs 8.8 million hectares of wheat-farmed area become more productive, climate-resilient and disease-resistant â a welcome development in a region where new climate change scenarios threaten sustained wheat production.
With multiple years of on-station and on-farm testing, the Wheat Research Institute (WRI) in Faisalabad, the Arid Zone Research Institute (AZRI) in Bhakhar, and the Barani Agricultural Research Institute in Chakwal released five varieties: Subhani 2021, MH-2021, Dilkash-2021, Bhakkar-20 and MA-2020.
The varieties, drawn from germplasm from the International Maize and Wheat Improvement Center (CIMMYT), were developed for different production environments in the Punjab province of Pakistan.
Dilkash-2021 was developed by WRI from a cross with a locally developed wheat line and a CIMMYT wheat line. MH-2021 and MA-2020 were selected from the CIMMYT wheat breeding germplasm through international trials and nurseries.
Subhani-21 and MA-2020 were selected from special trials assembled by CIMMYT for expanded testing, early access and genomic selection under the USAID-funded Feed the Future Innovation Lab for Applied Wheat Genomics at Kansas State University, in partnership with Cornell University and four South Asian countries (Bangladesh, India, Nepal and Pakistan).
Over the course of multiple years and locations, the new varieties exhibited a yield potential that is 5 to 20% higher than current popular varieties such as Faisalabad 2008, in addition to good grain quality and attainable yields of over 7 tons per hectare. They also showed an impressive resistance to leaf and yellow rusts, compatibility with wheat-rice and wheat-cotton farming systems, and resilience to stresses.
âIt is exciting to see new varieties coming out of these collaborative projects between the Pakistani breeding programs, CIMMYT and the university teams,â said Jesse Poland, associate professor at Kansas State University and director of the Wheat Genomics Innovation Lab.
Wheat breeder and WRI director Javed Ahmad (center, wearing a white cap) explains the performance of a new variety and its positive traits to visitors. (Photo: Muhammad Shahbaz Rafiq)
Closing the yield gap between research fields and smallholder fields
Despite all of these encouraging traits, releasing a new variety is just half of the battle. The other half is getting these new, quality seeds to markets quickly so that wheat growers can realize the benefits. A fast-track seed multiplication program for each of these varieties has been designed and implemented.
âPakistan has started to multiply early-generation seeds of rust-resistant varieties. These will be available to seed companies for multiplication and provision to farmers in the shortest possible time,â agreed wheat breeder and WRI Director Javed Ahmad and the National Wheat Coordinator Atiq Rattu.
Wheat breeder and WRI director Javed Ahmad (left) discusses performance of the new varieties with a colleague. (Photo: Muhammad Shahbaz Rafiq)
However, the current seed replacement rate is still low, mainly because new, quality seeds are rarely available at the right time, location, quantity, and price for smallholders. Strengthening and diversifying seed production of newly released varieties can be done by decentralizing seed marketing and distribution systems and engaging both public and private sector actors. Additionally, marketing and training efforts need to be improved for women, who are mostly responsible for household-level seed production and seed care.
In 2020, Pakistan harvested 25.7 million tons of wheat, up from 23.3 million tons a decade ago in 2010, which roughly matches its annual consumption of the crop. Pakistan is coming close to its goal of self-sufficiency, as outlined in the Pakistan Vision 2025, Food Security Policy 2018 and Vision for Agriculture 2030. Research shows that the public sector cannot extensively disseminate seeds alone; new policies must create an attractive environment to private sector partners, so that entrepreneurs are also attracted to the seed business. With continued efforts and a bold distribution and training effort, new releases like these will contribute to narrowing the yield gap between research stations and farmersâ fields.
A maize ear harvested from a “milpa,” the maize-based intercrop that is a critical source of food and nutritional security for smallholder farming communities in remote areas such as the Western Highlands of Guatemala. (Photo: Cristian Reyna)
The traditional milpa intercrop â in which maize is grown together with beans, squash, or other vegetable crops â can furnish a vital supply of food and nutrients for marginalized, resource-poor communities in the Americas, according to a study published today in Nature Scientific Reports.
One hectare of a milpa comprising maize, common beans, and potatoes can provide the annual carbohydrate needs of more than 13 adults, enough protein for nearly 10 adults, and adequate supplies of many vitamins and minerals, according to the study. The research was based on data from nearly 1,000 households across 59 villages of the Western Highlands of Guatemala and is the first to relate milpa intercropping diversity with nutritional capacity, using multiple plots and crop combinations.
âThe milpa was the backbone of pre-Columbian agriculture in North America, Mexico, and Central America,â said Santiago LĂłpez-Ridaura, specialist in agricultural systems and climate change adaptation at the International Maize and Wheat Improvement Center (CIMMYT) and lead author of the article.
âMilpa production anchored around locally-adapted maize is still an essential food and nutritional lifeline for isolated, often indigenous communities throughout Mexico and Central America, and can be tailored to improve their food and nutritional security, along with that of small-scale farmers in similar settings,â he added.
Maize for feed or food and nutrition?
In modern times, some 1 billion tons of maize are harvested yearly from about 200 million hectares worldwide. Much of this output results from intensive monocropping of hybrids that yield an average 10 tons per hectare, in places like the U.S.
This massive world harvest goes chiefly for animal feed, corn starch, corn syrup, ethanol, and myriad industrial products, but in sub-Saharan Africa, Latin America, and parts of Asia, maize remains a critical food staple, often grown by smallholder farmers with yields averaging around 1.5 tons per hectare.
The Western Highlands of Guatemala is among the worldâs poorest regions â a mountainous area ill-served by markets and where communities battered by food insecurity and malnutrition sow crops at altitudes of up to 3,200 meters, according to Cristian A. Reyna-RamĂrez, a co-author of the study from the Universidad AutĂłnoma Metropolitana-Xochimilco, Mexico.
âFully two-thirds of farmers in this region grow milpas based on maize but varying the intercrops with potatoes, faba bean, and even fruit trees,â Reyna-RamĂrez said. âOur study showed that combinations such as maize-common bean-faba bean, maize-potatoes, and maize-common bean-potatoes provided the most carbohydrates, proteins, zinc, iron, calcium, potassium, folate, thiamin, riboflavin, vitamin B6, niacin and vitamin C.â
The classic âmilpaâ intercrop comprises maize, beans, and squash. The bean plant climbs the maize stalk to reach sunlight and its roots add nitrogen to the soil; the squash leaves shade the soil, conserving moisture and inhibiting weed growth. Milpa systems are often grown on steep hillsides at a wide range of altitudes. (Photo: Cristian Reyna)
Better diets and routes out of poverty?
With typical landholdings of less than a quarter hectare and households averaging six members, Guatemalaâs Western Highlands inhabitants cannot depend on the milpa alone to satisfy their needs, LĂłpez-Ridaura cautioned.
âAs with many smallholder farm communities, lack of land and general marginalization traps them in a vicious circle of poverty and malnutrition, forcing them to experiment with risky cash crops or for working-age members to undertake dangerous and heartbreaking migrations to find work and send back remittances,â he explains.
According to LĂłpez-Ridaura, this study points the way for tailoring milpa systems to help communities that still rely on that intercrop or others that could benefit from its use.
Looking forward
Natalia Palacios Rojas, CIMMYT maize quality and nutrition expert and a co-author of this article, notes that calculations of this and other milpa studies consider raw nutrients and that research is needed on the nutritional contributions of cooked food and non-milpa foods such as poultry, livestock, home-garden produce, and purchased food.
âFurther work should also address the effects of storing milpa produce on its nutrient stability and how the seasonal availability of milpa crops impacts diets and nutrition,â Palacios said.
The authors are grateful for funding from the United States Agency for International Development (USAID) as part of Feed the Future, the U.S. Governmentâs global hunger and food security initiative, under the Buena Milpa project, as well as the support of the CGIAR Research Program on Maize.
A farmer in Nepal operates a water pump for drip irrigation. (Photo: Sharad Maharjan/IWMI)
Taken together, digital monitoring and readily available data on the status of groundwater resources provide a critical foundation for sustainable irrigation development. While much is known about surface water resources and hydrological and meteorological linkages between the Terai, Mid-Hills and Himalaya regions of the country, Nepal currently lacks a comprehensive system for groundwater resource monitoring.
To respond to this crucial information gap, the International Maize and Wheat Improvement Center (CIMMYT) and International Water Management Institute (IWMI) are partnering with the Government of Nepalâs Groundwater Resources Development Board to conduct a pilot which will develop and test a potential groundwater monitoring system with the goal of identifying an approach which can be gradually scaled out after project completion.
To this end, the project team organized an Inception and Consultation Workshop, which took place virtually on October 14, 2020. This was the first in a series under the Cereal Systems Initiative for South Asia (CSISA) Nepal COVID-19 and Resilience project, funded by the United States Agency for International Development (USAID) Nepal, which supports farmers and rural economies in their response to COVID-19 and addresses, among others, various issues and ways forward for sustainable irrigation development.
The session aimed to introduce the digital groundwater monitoring pilot to local stakeholders, identify monitoring objectives and information needs, facilitate multi-stakeholder and inter-ministerial dialogue, and generate feedback and endorsement of the project plan. Participants were from a wide range of backgrounds and disciplines, and included members of local and national authorities, research centers and universities.
Participants meet virtually at the multi-stakeholder dialogue for Nepalâs Digital Groundwater Monitoring pilot (Photo: Tim Krupnik/CIMMYT)
Madhukar Rajbhandari, director general of the Government of Nepalâs Department of Water Resources and Irrigation, opened the event and during his address highlighted the importance of groundwater irrigation for Nepalâs farming systems and livelihoods. He also captured the challenges which the country faces when developing groundwater irrigation, from polluted water resources through urbanization to lack of market access and the high maintenance costs of irrigation infrastructure. Rajbhandari noted that âagricultural and irrigation projects lack coordinationâ and expressed his hope that âthrough this pilot, the way is paved for a collaborative approach to develop practical groundwater solutions for farmers.â
The session introduced participants to the project and its background, leading breakout sessions for two groups: the first containing local, state and national government representatives; the second comprising farmers, researchers and members of industry. Each group was asked to identify the groundwater monitoring objectives and information needs that they would have as different types of users, and to provide feedback and recommendations to improve the project work plan.
The feedback showed that while government representatives are largely interested in developing a better understanding of the groundwater development potential, researchers and farmers are more concerned with possible discharge and water quality. Monitoring frequency was also identified as useful for daily to monthly timescales.
The group discussion revealed participantsâ keen interest in consolidating and monitoring groundwater information, which highlights the importance of stakeholder engagement when developing pilots such as these, to ensure that when scaling is achieved, it caters to specific needs. Participants also expressed a strong interest in bringing the results of the project within the ambit of national policy, which would achieve the streamlining of data collection protocols for standardized, publicly accessible, data collection mechanisms.
âIt is very encouraging to see such active participation and engagement from all the participants throughout the workshop,â noted Timothy Krupnik, project leader and a senior scientist at CIMMYT. âWe look forward to maintaining this momentum, to support Nepalâs efforts in strengthening its capacity for sustainable irrigation.â
