Climate change will lower global wheat production with the most negative impacts occurring in Africa and South Asia, reveals a new study released by the International Maize and Wheat Improvement Center (CIMMYT).
Read the full story here.
Faced with climate change and having to keep pace in the race to feed the worldâs growing population, farmers of staple crops like wheat are under pressure to constantly increase yield per hectare.
Increasing yield gains is especially important in Afghanistan, where per capita consumption of wheat is nearly three times more than the global average and wheat accounts for up to 60% of daily caloric intake of the average Afghan citizen.
The International Maize and Wheat Improvement Center (CIMMYT) develops and distributes improved seed targeted toward diverse wheat growing regions in the developing world, including Afghanistan, a net importer of wheat. A study by CIMMYT scientists, published in Crop Science, measured yield gain and improvement in a variety of traits of CIMMYT developed varieties compared against local wheat, over a 14-year period. The results showed the CIMMYT varieties confer yield gains, contributing to an increase in Afghanistanâs wheat productivity.
In terms of yield, the CIMMYT varieties showed an increase of 123 kilograms per hectare (kg/ha) over the time interval studied, compared to 107 kg/ha for local varieties.
âThis study shows continual increases in yield from CIMMYT varieties across Afghanistan,â said lead author Rajiv Sharma. âThis shows the potential of genetically improved germplasm to increase yields, strengthen resistance to diseases and improve other important traits.â
Researchers also examined specific traits, like days to heading and overall plant height. Days to heading refers to the number of days from planting to when the plant is ready to be harvested and overall plant height is the highest measurement a plant reaches. This is important because if a wheat plant grows too high, it will lodge (fall over) under its own weight, rendering it non-harvestable.
Across the CIMMYT varieties there was a 1.8 day per year reduction in days to heading. This is a positive sign for Afghan wheat production as research has shown that crop durations will be reduced because of climate-associated stresses. Shorter crop duration also reduces the cost of crop production, since shorter crop duration reduces the requirements for water, labor, fertilizer, and other resources.
In terms of plant height, the CIMMTY varieties showed a gain of 0.77 cm per year. Although a negative correlation between plant height and grain yield has been reported in other studies, this is not the case in Afghanistan. Increased plant height is often an indicator of higher biomass (the amount of aboveground volume including leaves and stems which might fall to the ground) which drives higher yield, provided the plant does not lodge. Higher biomass is also required in many developing countries, including Afghanistan, to produce straw that is used dry fodder feed for livestock. This appears to result from selections to increase overall production, mitigate negative impacts and fulfil the changing preference of farmers.
âThis kind of evaluation is important in determining the efficacy of CIMMYTâs efforts to provide  improved wheat varieties tailored to diverse production environments around the world,â said Alison Bentley, co-author of the study and director of CIMMYTâs Global Wheat Program. âIt also makes a strong case for continued investment in plant breeding and for the collaboration between Afghanistan and CIMMYT.â
Read the study: Plant breeding increases spring wheat yield potential in Afghanistan
Cover photo: Farmers working in a field in the Shibar Valley in Bamian province, Afghanistan. (Adam Ferguson/The New York Times)
Wheat is a strategically important crop for Afghanistan because as a major source of nutrition â accounting for up to 60% of a familyâs daily caloric intake â it is linked directly to national food security. However, despite occupying over 2.5 million hectares of arable land across the country, Afghanistan does not currently produce enough wheat to meet the needs of a growing population. On average, annual production is estimated at around 5 million metric tons â 2 million metric tons less than needed â and as a result Afghanistan makes up this significant shortfall by importing wheat flour from neighboring countries where wheat productivity is significantly higher.
There is tremendous potential to increase national wheat productivity by introducing improved agronomic practices and making use of suitable farming technologies. However, given Afghanistanâs vast agro-ecological diversity, it is essential that best practices are recommended based on local conditions, as these vary greatly across the country.
Take seeding, for instance. Sowing wheat seed at the optimum time has been shown to help maximize yields and significant research has been undertaken to determine the optimal sowing dates for winter and spring wheat in different areas. These times are governed not only by environmental requirements and growing cycles, but also by the need to avoid certain diseases and insect pests, which may be more prevalent at specific times of year.
But these can vary widely even within a season. For example, research shows that the best time to sow irrigated winter wheat in Afghanistanâs hot and arid western provinces is from the second week of October up until the end of the month. However, the optimum window falls one month later in the more mountainous and forested provinces of the East, and even later for rain-fed wheat.
The same distinctions apply to seeding and fertilizer application rates, which can vary subtly between similar regions. Consider that the optimum seed rate for irrigated wheat sown using the broadcast method is the same in both the Northern and Central zones, 25-30 kilograms per jerib (approx. half an acre). One might expect the optimum rates for row cultivation to match, but in fact they differ by two kilograms. This might not seem like much, but given how significantly seed density and spacing influence crop yield and quality, these figures are vital knowledge for farmers looking to maximize their yield potential.
To help disseminate these research-based recommendations to farmers and local agricultural extension staff, researchers at the International Maize and Wheat Improvement Center (CIMMYT) have partnered with Afghanistanâs Ministry of Agriculture, Irrigation and Livestock, Michigan State Universityâs Global Center for Food Systems Innovation and the USAID to compile four new booklets featuring zone-specific advice for irrigated and rain-fed systems in each of Afghanistanâs main agro-ecological zones.
Covering between four and ten provinces each, these guides include localized recommendations for the best sowing dates, nutrient management, weed management, and best practices in irrigation, arming wheat farmers with the key information they need to effectively increase production in their area and support the countryâs wider food security needs.
More information is available in the booklets below:
Zone-Specific Recommendations for: Northern Region
Zone-Specific Recommendations for: Central Region
Zone-Specific Recommendations for: Eastern Region
Zone-Specific Recommendations for: Western Region
Cover photo: The optimal time for wheat sowing in Afghanistan varies by region according to the country’s vast agro-ecological diversity. CIMMYT recommends a localized approach. (Photo: Rajiv Sharma/CIMMYT)
âIn Afghanistan, wheat is synonymous with food,â says Rajiv K. Sharma, formerly a senior scientist at the International Maize and Wheat Improvement Center (CIMMYT). Standing at about 250kg per year, the countryâs per capita consumption of the crop is among the highest in the world. However, Afghanistan does not have a robust wheat research and development system. The majority of wheat varieties have been introduced from outside the country and the national wheat seed replacement rate is one of the lowest in the world at around 5%.
In a bid to strengthen research and development and boost crop productivity in the country, CIMMYT scientists have collaborated with Michigan State University and USAID to design a new, illustrated manual for wheat researchers, intended to aid them during experiments and facilitate smooth and timely data collection. As applied wheat research requires the monitoring and measurement of both qualitative and quantitative traits by different researchers across multiple locations, consistency of approach is crucial.
As well as providing descriptions of characteristics like glaucousness (the presence or absence of leaf waxes) and advice on measuring leaf area, the manual provides several different scales for determining the extent to which a wheat plant is affected by frost damage, cereal rusts or foliar diseases like Septoria and powdery mildew. Covering everything from leaf angle to chlorophyll content, this resource ensures that scientists throughout Afghanistan are supported to follow the same observation and measurement protocols while recording trial data, ensuring a standardized approach, thus bolstering the countryâs wheat research sector and ensuring the data is also aligned to international projects.
The manual has since been distributed to National Agricultural Research System (NARS) researchers and other stakeholders across the country, accompanied by a number of CIMMYT-led trainings on how best to use the resource.
Download the manual here: Wheat Field Trial Data Collection Manual
Cover photo: Researchers check for stand reduction in wheat seedlings in Afghanistan. (Credit: CIMMYT)
Agriculture is central to South Asian economies, lives and livelihoods. However, the challenges of an increasing population and brisk economic growth are straining the agriculture sector as it struggles to meet the present and future demand for food, nutritional security, and economic development. Not only this, the three Cs â COVID, climate change and conflict â are fueling the growing fragility in food systems across the world.
To address these issues and find potential solutions, the Borlaug Institute for South Asia (BISA) organized a high-level meeting with top agriculture ministry officials from its neighboring countries â Sri Lanka, Nepal, Bangladesh, Bhutan, India and Pakistan â to collaborate and learn from each other.
BISAâs outreach to Indiaâs neighbors in South Asia has already produced results. Data from the BISA farm in Ludhiana, India, on resistance to yellow rust that affects wheat crop has been used in Nepal, Afghanistan, and Pakistan. Genomic prediction evaluation for grain yield and other traits worked on at BISA through the help of the Global Wheat Program of the International Maize and Wheat Improvement Center (CIMMYT) has been extended to Pakistan, Bangladesh, and Nepal since 2020. Regular training is organized for students, scientists and farmers in India on breeding and climate resistant technologies, and BISA scientists organize courses in Nepal on climate-smart technologies.
Read more in Amar Ujala (published in Hindi): Can agriculture bring South Asian countries together?
Cover photo: Tara Miah (50) is a farmer from Rajguru in Rahamanbari union, Barisal, Bangladesh. He used seeder fertilizer drills to plant wheat on his fields. Previously, this was done manually. SFD has resulted in a better harvest for Miah. (Credit: Ranak Martin)
Rust pathogens are the most ubiquitous fungal pathogens that continue to pose a serious threat to wheat production. The preferred strategy to combat these diseases is through breeding wheat varieties with genetic resistance.
Landraces are a treasure trove of trait diversity, offer an excellent choice for the incorporation of new traits into breeding germplasm, and serve as a reservoir of genetic variations that can be used to mitigate current and future food challenges. Improving selection efficiency can be achieved through broadening the genetic base through using germplasm pool with trait diversity derived from landraces.
In a recent study, researchers from the International Maize and Wheat Improvement Center (CIMMYT) used Afghan landrace KU3067 to unravel the genetic basis of resistance against Mexican races of leaf rust and stripe rust. The findings of this study not only showcase new genomic regions for rust resistance, but also are the first report of Lr67/Yr46 in landraces. This adult plant resistance (APR) gene confirms multi-pathogenic resistance to three rust diseases and to powdery mildew.
Using genotype sequencing and phenotyping, the authors also report an all-stage resistance gene for stripe rust on chromosome 7BL, temporarily designated as YrKU. The genetic dissection identified a total of six quantitative trait locus (QTL) conferring APR to leaf rust, and a further four QTL for stripe rust resistance.
Although use of landraces in wheat breeding has been practiced for a long time, it has been on a limited scale. This study represents a significant impact in breeding for biotic stresses, particularly in pest and disease resistance.
Read the full study here: Identification and Characterization of Resistance Loci to Wheat Leaf Rust and Stripe Rust in Afghan Landrace âKU3067â
Cover photo: Yellow rust screening takes place at a CIMMYT experimental station in Mexico. (Credit: Sridhar Bhavani/CIMMYT)
For thousands of years, farmers in Afghanistan, Turkey and other countries in the region, have been breeding wheat, working closely with the environment to develop traditional wheat varieties known as landraces. Untouched by scientific breeding, landraces were uniquely adapted to their environment and highly nutritious.
As agriculture became more modernised and intensified, it threatened to push these traditional landraces into extinction, resulting in the loss of valuable genetic diversity. Institutions around the world decided to act, forming germplasm collections known as genebanks to safely house these landraces.
In 2009, a team of wheat scientists from the International Maize and Wheat Improvement Center (CIMMYT), the International Center for Agricultural Research in the Dry Areas (ICARDA), the UN Food and Agriculture Organization (FAO), and national partners set off on a five-year expedition across Central Asia to collect as many landraces as they could find. The project, led by FAO Cereal Breeder and former CIMMYT Principal Scientist Alexey Morgunov, was made possible by the International Treaty on Plant Genetic Resources for Food and Agriculture Benefit-Sharing Fund.
The project had two main missions. The first is to preserve landrace cultivation in three countries, Afghanistan, Turkey and other countries in the region by selecting, purifying, and multiplying the landraces and giving them back to farmers. The second is to scientifically evaluate, characterize and use these landrace varieties in ongoing breeding programmes, exchange the information between the countries, and to deposit the seeds in genebanks to safely preserve them for future generations.
The latest results from the project were published in July in the journal Crops. The study, authored by a team of experts from CIMMYT, ICARDA, FAO, and research institutes in Afghanistan, Turkey and other countries in the region, compared the diversity, performance, and adaptation of the collected wheat landraces with modern varieties grown in the regions using a series of field experiments and cutting-edge genomic tools.
âLandraces are very useful from a breeding perspective because they have been cultivated by farmers over thousands of years and are well adapted to climate change, have strong resistance to abiotic stresses and have very good nutritional quality,â said Rajiv Sharma, a CIMMYT senior scientist and co-author of the paper.
âWe were interested in seeing how well landraces adapt to certain environments, how they perform agronomically, and whether they are more diverse than modern varieties grown in these regions â as well as give their improved versions back to farmers before they are lost.â
The experiments, which were carried out in 2018 and 2019 in Turkey, and 2019 in Afghanistan, and other countries in the region revealed several physical characteristics in landraces which are no longer present in modern varieties. For example, the team found striking differences in spike and grain colors with landraces more likely to have red spikes and white grains, and modern varieties tending to have white spikes and red grains. This may have adaptive values for high altitudes and dry conditions.
A surprising finding from the study, however, was that landraces were not more genetically diverse than modern landraces.
âMany people thought that when we went from cultivating landraces to modern varieties, we lost a lot of diversity but genetically speaking, thatâs not true. When you look at the genomic profile, modern varieties are just as diverse as landraces, maybe even a little bit more so,â said Sharma.
When the team compared landraces and modern varieties on crop performance, the results were mixed with modern wheat varieties outyielding landraces in half of the environments tested. However, they found that the highest yielding landraces were just as good as the best modern varieties â a reassuring finding for farmers concerned about the productivity of their crops.
A new breeding paradigm Â
The results of the study have important implications for landrace conservation efforts in farmersâ fields and in future breeding strategies. While crossing wheat landraces with modern varieties to develop improved modern varieties is not new, the authors proposed a novel alternative breeding strategy to encourage the continued cultivation of landraces: improving landraces by crossing them with other landraces.
âIn order to maintain landraces, we have to make them competitive and satisfy farmersâ needs and requirements. One option is that we breed landraces,â said Sharma.
âFor example, you might have a landrace that is very-high yielding but susceptible to disease. By crossing this variety with another landrace with disease-resistant traits you can develop a new landrace better suited to the farmer and the environment. This approach maintains all the features of landraces â we are simply accelerating the evolution process for farmers to replace the very fast disappearance of these traditional varieties.â
This approach has already been used by crop scientists at the University of California, Davis who has successfully developed and registered âheirloom-like varietiesâ of dry beans. The varieties trace about 98% of their ancestry to landraces but are resistant to the common mosaic virus.
Heirloom food products are becoming increasingly popular with health-conscious consumers who are willing to pay a higher price for the products, garnering even more interest in conserving traditional landraces.
One of the overarching aims of the project was to give wheat landraces back to farmers and let nature take its course. Throughout the mission, the team multiplied and returned landrace seed to over 1500 farmers in communities across Afghanistan, Turkey and other countries in the region. The team also supplied over 500 farmers with improved landrace seed between 2018 and 2019.
Despite the political turmoil facing these countries, particularly Afghanistan, farmers are still growing wheat and the projectâs contribution to food security will continue.
These landraces will take their place once more in the farming landscape, ensuring on-farm wheat diversity and food security for future generations.
This research was conducted with the financial assistance of the European Union within the framework of the Benefit-Sharing Fund project âW2B-PR-41-TURKEYâ of the FAOâs International Treaty on Plant Genetic Resources for Food and Agriculture.
The UN High Commissioner Michelle Bachelet recently said of Afghanistan, “In the wake of years of conflict, and since the takeover by the Taliban in August last year, the country has been plunged into a deep economic, social, humanitarian and human rights crisis” (UN News 2022a). International humanitarian agencies and NGOs have persisted in supporting the population, half of whom are suffering food insecurity, and some of whom are facing unprecedented and catastrophic levels of hunger (UN News 2022b). The conflict in Ukraine is exacerbating the crises in poor import-dependent countries and humanitarian programmes, and Afghanistan will be among the most affected (Bentley and Donovan 2022).
The rural sector underlies Afghanistanâs economic potential, with agriculture as the foundation of the economy. Wheat, both irrigated and rainfed, is the principal agricultural crop, and bread is the major component of the Afghan diet. For decades the country has relied for food security on neighbors such as Kazakhstan and Pakistan and import dependence appears to be a permanent feature of the agricultural economy (Sharma and Nang 2018).
In a recent paper published in Plants, People, Planet, CIMMYT scientists and partners from SOAS University of London, Afghanistan Research and Evaluation Unit, FAO-Afghanistan, The HALO Trust, Afghanaid and the Agricultural Research Institute of Afghanistan call for renewed investment in Afghanistanâs wheat and agricultural sector.
Improved CIMMYT wheat germplasm has supported agricultural development
CIMMYTâs activities in Afghanistan have focused primarily on supporting the national agricultural research system through the provision of elite, widely adapted germplasm with strong disease resistance. Recent estimates of genetic gains over 14 years (2002-2003 to 2015-2016) of testing of CIMMYTâs Elite Spring Wheat Yield Trial material across 11 locations in Afghanistan documents significant grain yield progress of 115 kg/year. Average yields across 11 testing locations ranged from 3.58 to 5.97 t/ha (Sharma et al., 2021). This indicates that yield potential can be increased through introduction and testing of internationally improved germplasm.
But such investment in research has come to a halt. Local public- and private-sector wheat breeding activities have been largely absent in Afghanistan for over a decade. Hence, wheat productivity remains low due to the limited availability of improved varieties, inadequate quality seed production and distribution. Although in the short term, humanitarian interventions are likely to be the major determinant of food security, we propose that strategic rebuilding of the wheat system will lay the foundation for restoring Afghanistanâs agricultural production, food supplies, nutrition and health. Here we signal opportunities for future improvement.
Opportunities to build climate resilience and enhance seed systems
The need for climate-resilient varieties that meet farmersâ varied requirements and consumer preferences is paramount. Afghan farmers need varieties with improved traits such as heat and drought resilience, incorporating functional variation from existing landrace collections. In addition, agronomic interventions such as conservation agriculture will offer substantial benefits in buffering environmental stresses.
The technological pathways for seed (re-)distribution are a critical part of the innovation pathway from plant breeding to production and productivity. Given the particularities of markets in Afghanistan, both the public sector and the private sector often fail to reach farming geographies that are remote, diverse, and unserved by physical and institutional infrastructure. For many years, basic public services and agricultural interventions have been provided by the NGO sector, and this form of delivery continues. Hence, local âinformalâ systems for seed and inputs are important to smallholder farmers.
Investment to support both irrigated and rain-fed wheat production
Rehabilitation of ancient irrigation practices and infrastructure could once again serve local farming in a way that supports stable production, restores Afghan heritage, and rebuilds social cohesion. However, there are no easy solutions to the challenges of increasing irrigation to boost agriculture. Although yields are lower, there is potential to optimize breeding specifically for rain-fed production. We expect rain-fed agriculture to continue given the limitations of water and infrastructure access.
Wheat improvement must be embedded in the wider agricultural environment. There is a renewed need for a deep understanding of social, political, and cultural systems and how they vary between villages, and from districts, provinces, and regions to people groups. We need to re-envision the roles of men and women in agriculture, and investment in skills and capacity building to provide a stable foundation for the eradication of poverty and food insecurity.
A new wheat program for Afghanistan
We highlight the urgent need for:
These foundations will support the wider regeneration of Afghanistanâs agricultural sector and enhance food security, nutrition and health of some of the worldâs most vulnerable populations.
Full paper
Poole, N., Sharma, R., Nemat, O.A., Trenchard, R., Scanlon, A., Davy, C., Ataei, N., Donovan, J. and Bentley, A.R. (in production). Sowing the wheat seeds of Afghanistan’s future. Plants, People, Planet DOI: https://doi.org/10.1002/ppp3.10277
References
Bentley, A. and Donovan, J. (2022). What price wheat? Crisis in Ukraine underscores the need for long-term solutions for global food security. Retrieved 16 June 2022, from https://staging.cimmyt.org/blogs/what-price-wheat/.
Sharma, R.K. and Nang, M. (2018). Afghanistan wheat seed scenario: Status and imperatives. International Journal of Agricultural Policy and Research 6(5): 71-75 DOI: https://doi.org/10.15739/IJAPR.18.008
UN News (2022a). Afghanistan facing âthe darkest momentsâ in a generation. Retrieved 16 June 2022, from https://news.un.org/en/story/2022/06/1120492.
UN News (2022b). Afghanistan: Nearly 20 million going hungry. Retrieved 16 June 2022, from https://news.un.org/en/story/2022/05/1117812.