Halima Begum wanted to increase her income by providing mechanization services to other farmers in Bangladesh’s Chuadanga district, but she was limited by the level of physical effort required. Starting the engine of her tractor was difficult and embarrassing — cranking it required a lot of strength and she had to rely on others to do it for her. She was also afraid she would get injured, like other local service providers.
Women in rural areas of Bangladesh are often hesitant to work in the fields. Social norms, limited mobility, physical exertion, lack of time and other constraints can cause aspiring female entrepreneurs to step back, despite the prospect of higher income. The few women like Halima who do step out of their comfort zone and follow their dreams often have to overcome the physical effort required to operate these machines.
Starting the tractor is a daunting task on its own and the possibility of having to do it multiple times a day adds to the reluctance of ownership.
To make manual cranking a thing of the past for Bangladeshi women entrepreneurs, and to encourage others, the International Maize and Wheat Improvement Center (CIMMYT), through the Cereal Systems Initiative for South Asia-Mechanization and Irrigation (CSISA-MI), is supporting small businesses who manufacture and sell affordable mechanical self-starter attachments for two-wheel tractors.
The self-starter is a simple spring-loaded device mounted over the old crank handle socket, which allows users to start the engine with the flick of a lever.
For women like Begum, manually starting a tractor was a difficult task that is now gone forever.
“I used to struggle quite a lot before, but now I can easily start the machine, thanks to this highly convenient self-starter,” Begum said.
The self-starter reduces the risk of accidents and coaxes hesitant youth and women to become entrepreneurs in the agricultural mechanization service industry.
CIMMYT is supporting businesses like Janata Engineering, which imports self-starter devices and markets them among local service providers in the district of Sorojgonj, Chuadanga district. The project team worked with the owner, Md. Ole Ullah, to organize field demonstrations for local service providers, showing how to use and maintain the self-starter device.
The Cereal Systems Initiative for South Asia-Mechanization and Irrigation (CSISA-MI) is led by the International Maize and Wheat Improvement Center (CIMMYT) and funded by the United States Agency for International Development (USAID). The project focuses on upstream market interventions in Bangladesh, ensuring technologies are reliably available in local markets and supported by an extensive value chain.
The report describes work with national and global partners using state of the art technology to measure traits and performance for faster development of high-yielding, heat- and drought- varieties; rapidly diagnosing diseases in farmers’ fields; supporting gender equality in agricultural innovations, and much more.
With its national partners, WHEAT released 48 new CGIAR-derived wheat varieties to farmers in 2018, and developed 11 innovations related to farm management practices or social sciences.
Western Europe is in the midst of an intense heat wave that started at the end of June. The southern French commune of Villevieille recorded a temperature of 45.1 °C, breaking the country’s all-time record. The heat also set new temperature records in Germany and the Czech Republic. Other countries like Italy, Spain and Portugal are also gripped with temperatures much higher than normal.
Scientists have attributed the soaring temperatures to the combination of a storm over the Atlantic Ocean and high pressure over central Europe, which is importing hot air from the Sahara. Though heat waves are not uncommon in Europe, this one was unusually early. Experts say climate change is making heat waves more common (Global warming of 1.5 °C IPCC Special Report).
Apart from human health, the heat wave is already causing significant damage in agriculture. Major wheat growers experienced temperatures of 40 °C and higher. This is of great concern, as the heat wave occurred during the crop’s critical growth stages. Wheat is a cool season crop with an optimal daytime growing temperature of 15 °C during the critical reproductive stage. Wheat plants exposed to high temperatures around the period of flowering lose fertility due to pollen dehydration, resulting in less grain formed. It is calculated that for every degree above the optimum 15 °C, wheat experiences a yield reduction of three to four percent.
If a heat wave like such as this one had occurred one month earlier, at the end of May, when Northern European wheat is in full bloom, it could have caused up to 50 percent yield loses, a devastating blow to the European agriculture and food sectors costing billions of Euros.
The response of scientists
Breeding heat tolerant wheat varieties remains one of the most strategic approaches to cope with the risk of unseasonal heat waves. The International Center for Agricultural research in Dry Areas (ICARDA) started in 2012 to use field stations that experience continuous heat-stress to select new wheat cultivars better primed to tolerate this stress.
Similarly, two heat-stress experimental farms were developed in West Africa to test durum wheat germplasm. In collaboration with Prof Rodomiro Ortiz of the Swedish University of Agricultural Sciences (SLU) Department of Plant Breeding, the stations of Kaédi in Mauritania and Fanaye in Senegal were upgraded in partnership with the Centre National de Recherche Agronomique et de Développement Agricole (CNRADA) and the Institut Sénégalais de Recherche Agricole (ISRA).
To convert this success into cultivars that could be grown, heat tolerance must be combined with the ability to cope with drought stress. An experiment was devised at the Marchouch station in Morocco, where plastic tunnels were placed on the wheat plants at the time of flowering to raise temperatures to above 40 °C and simultaneously prevent any rainfall from reaching the plants.
When all other tested varieties lost more than 50 percent yield to the two combined stresses, the ICARDA-INRA (Institut Nationale de la Recherche Agronomique in Morocco) cultivar Faraj lost only 25 percent, a major positive result considering the severity of the stresses tested. Along the same principles, more than 60 wheat varieties of ICARDA origin have been released by national breeding programs in Central and West Asia and North Africa regions and sub- Saharan Africa regions in the last five years alone, thanks to the ability of the germplasm to adapt to some of the most severe wheat stresses occurring around the world.
Can Europe take advantage of success stories?
In the USA and Canada, farmers grow mostly wheat varieties developed and commercialized by public wheat breeding programs. These cultivars have been very popular and public sector wheat-breeding activities are vital to the industry.
In Australia, wheat breeding is conducted by the private sector. However, public researchers are spending the same amount of money on pre-breeding as they did 10 years ago on breeding and variety development together. To take advantage of some of the success stories of ICARDA and CIMMYT, the Australian wheat breeding programs established 10 years ago the CIMMYT-Australia-ICARDA Germplasm Evaluation project (CAIGE). Each year, Australian breeders visit the trials of ICARDA in Morocco and CIMMYT in Mexico. They select the top high yielding wheat genotypes that combine drought and heat tolerance, with other useful traits. These are then imported and tested across Australian sites to confirm the best one for commercialization or use in hybridization programs.
In Europe, the situation is more like Australia, and public researchers do not work directly on the commercialization and development of varieties, which is left to the private companies. Instead, public research focuses on pre-breeding to develop new breeding techniques and on high-risk, longer-term targets, thereby supporting the private sector and farmers with high-tech innovations.
CGIAR centers such as ICARDA and CIMMYT have worked in close collaboration with European universities and advanced research institutions for a long time to develop and adapt the most novel technologies for pre-breeding. It might also be advantageous for European private sector companies to start taking advantage of CGIAR stress-tolerant wheat varieties and develop a system similar to CAIGE used by Australian breeders. By taking advantage of similar environments in Morocco and Mediterranean environments in Europe, European breeders can select promising germplasm of tomorrow and provide the continent’s agricultural sector with a practical defense against future heat waves.
In the highlands of Ethiopia and the oases of the Sahara this crop has been cultivated for thousands of years. Today, smallholder farmers still grow it on marginal lands to assure production for their own consumption. However, durum wheat is no longer just a staple crop for food security but has become a major cash crop. In fact, the pasta, burghul and couscous industry currently purchase durum grain at prices 10 to 20% higher than that of bread wheat. Africa as a whole imports over €4 billion per year of durum grain to provide the raw material for its food industry. Hence, African farmers could obtain a substantial share of this large market by turning their production to this crop.
“A participatory approach, that uses the farmers themselves to guide the breeding decisions helps hugely in achieving success. A simple example was for an advanced line that I really liked: the yield was very high, the grains very big, and it had very good disease resistance. Still, when I showed it to farmers they did not like it. The main reason was that it was too short, and they could not get enough straw to feed their livestock. This is but an example on how incorporating farmers’ opinions save me from investing a lot of efforts in releasing and promoting a variety that would have never made it to cultivation”.
Challenges and promises
New breeding technologies offer great promise for expanding the area of durum wheat production in SSA. However, this remains primarily dependent on the market ability to purchase these grains at a higher price to stimulate farmer adoption. Because of its industrial nature, durum wheat has often been disregarded by SSA policy makers in favor of bread wheat as a more direct “food security” approach. Considering that the most cultivated durum varieties are more than 30 years old, there is a significant genetic yield gap that could be filled through the release and commercialization of more modern varieties.
A significant effort has been made to expand the production of improved durum wheat cultivars to supply raw materials to the food industries. The pasta producers used to rely on massive importation of durum wheat grains, which was not a sustainable long-term business strategy due to high and volatile costs. Further, the purchase of foreign grains competed with other national priorities for the use of governmental hard currency stocks.
Meeting the industrial standards
Recent investments in the pasta industry are proving extremely promising in Ethiopia thanks to new food habits of the growing urban populations, which are looking for fast and tasty foods, while still cheap and nutritious. The Ethiopian Millers Association has eagerly explored the possibility to procure the needed raw material directly from local farmers to reduce production costs and increase competitiveness against foreign pasta imports. Unfortunately, the local production did not guarantee sufficient rheological grain quality to satisfy the industrial needs. In fact, grain of tetraploid landraces does not meet industrial standards in terms of color or protein quality.
Hence, specific incentives needed to be provided to farmers to obtain industrial-grade harvests. The scope of the Ethiopian-Italian cooperation project for the Agricultural Value Chain in Oromia (AVCPO) was to re-direct some of the already existing bread wheat production system of the Bale zone toward the more lucrative farming of durum wheat for the industry.
The process acted on the key elements required by the pasta industry to stabilize and self-sustain the value chain: (a) competitive price, (b) high rheological quality for conversion into pasta, (c) easy and timely delivery, (d) consistent stock of grains and predictable increases over years.
Based on a rigorous large-scale study spanning five decades
of wheat breeding progress under cropping systems with low, medium and high
fertilizer and chemical plant protection usage, the authors conclude that
modern wheat breeding practices aimed at high-input farming systems have
promoted genetic gains and yield stability across a wide range of environments
and management conditions.
In other words, wheat breeding benefits not only large-scale
and high-input farmers but also resource-poor, smallholder farmers who do not
use large amounts of fertilizer, fungicide, and other inputs.
This finding underscores the efficiency of a centralized
breeding effort to improve livelihoods across the globe – the philosophy behind
the breeding programs of the International Maize and Wheat Improvement Center
(CIMMYT) over the past 50 years.
It also contradicts a commonly held belief that breeding for
intensive systems is detrimental to performance under more marginal growing
environments, and refutes an argument by Green Revolution critics that breeding
should be targeted to resource-poor farmers.
“Given that wheat is the most widely grown crop in the
world, sown annually on around 220 million ha and providing approximately 20%
of human calories and protein, the social and economic implications are large,“
Among other implications,
The study found that modern breeding has reduced
groups of genes (haplotypes) with negative or neutral effects – a finding which
will help breeders combine positive haplotypes in the future, including for
The study demonstrates the benefits of breeding
for overall yield potential, which — given that wheat is grown over a wider
range of environments, altitudes and latitudes than any other crop, with widely
ranging agronomic inputs – has significant cost-saving implications.
Braun and Reynolds acknowledge that the longstanding beliefs
challenged by this study have a range of influences, from concern about rural
livelihoods, to the role of corporate agribusiness and the capacity of Earth’s
natural resources to sustain 10 billion people.
While they welcome the conclusions as a validation of their
work, they warn against seeing the study as “a rubber stamp for all things
‘high-input’” and encourage openness to new ideas as the need arises.
“If the climate worsens, as it seems destined to, we must
certainly be open to new ways of doing business in crop improvement, while
having the common sense to embrace proven technologies, ” they conclude.
Kenya research station offers a unique wheat science platform with global impact
By Joshua Masinde
Stem rust, which occurs
mainly in warm and humid conditions, is a serious biotic threat to wheat that
can destroy healthy plants just a few weeks before harvest, resulting in huge
yield losses to farmers. Along with leaf rust and stripe rust, it is the among
the world’s most threatening wheat fungal diseases, dreaded by farmers for
Two decades ago, a virulent race
of stem rust — identified as Ug99 — was identified in Uganda. The race went
on to cause major epidemics in Kenya in 2002 and 2004. It continues to evolve
and emerge into new races. Ug99 and its variants have since spread across East African
highlands to South Africa, and to Yemen and Iran, threatening regional food
To tackle this stem rust
pathogen, the International Maize and Wheat Improvement Center (CIMMYT) and Cornell
University established the International Stem Rust Phenotyping Platform in
Njoro, Nakuru County, Kenya, in collaboration with the Kenya Agricultural and
Livestock Research Organization (KALRO) through the Durable Rust Resistance in
Wheat (DRRW) project in 2008.
Over the past decade, wheat breeders and pathologists have worked collaboratively at the facility to stay ahead of this fast-evolving wheat stem rust fungus. This partnership has resulted in the release of over 150 wheat lines around the world, with resistance to Ug99 and its variants. The development of these high-yielding varieties suitable to various agro-ecologies has been possible with support from the Bill & Melinda Gates Foundation and the UK Department for International Development (DFID) initially through the DRRW project, and presently as part of the Delivering Genetic Gain in Wheat (DGGW) project, managed by Cornell University.
Phenotyping – the use of field-testing technology to identify desired plant traits – is a core component in the facility. The facility uses the CIMMYT Mexico-Kenya shuttle breeding system to quickly evaluate and select wheat lines for stem rust resistance. It also evaluates wheat germplasm from different countries, and “mapping populations” — crosses of diverse parents — to identify and characterize new sources of rust resistance.
The CIMMYT Mexico-Kenya
shuttle breeding system allows breeders to plant at two locations to rapidly
advance new plant generations and expose the wheat to different stresses
(abiotic and biotic). Testing in Obregon yields wheat lines adaptable to
different agro-ecological zones, and with resistance to local races of leaf
rust and stem rust pathogen, while additional testing in Kenya enhances stem
rust resistance to Ug99 and its variants. This enables the Njoro facility to screen
and select about 1,500-2,000 segregating wheat populations over the course of
“Through the CIMMYT Mexico-Kenya shuttle breeding, continuous testing of wheat germplasm, speed breeding and use of modern marker technologies for genomic selection, we innovate continuously to develop improved wheat lines with a package of desired traits in a much shorter period of time,” explained Mandeep Randhawa, CIMMYT wheat breeder and wheat rust pathologist.
Scientists at the facility
evaluate about 10,000 lines from yield trials for stem rust resistance over two
seasons. The best performing lines undergo second year of yield tests under
five different environments in Obregon, Mexico: full irrigation, drought, flat bed, raised bed
and heat stress. Breeders then select and compile high-yielding lines and
distribute them as international nurseries to national partners with the help of
CIMMYT’s germplasm bank.
The Njoro screening facility
has a capacity of testing 50,000 wheat lines in a year. As many as 20 countries
send their germplasm to the facility for stem rust evaluation. About 600,000
wheat lines have been evaluated at Njoro over the last 10 years.
The critical challenge for
breeders is to combine all desirable traits into single lines in a shorter period:
say five, instead of 10 years. Such elaborate breeding efforts require
sustained support and international cooperation to develop high-yielding stress
resilient lines suited to various agro-ecologies.
Training and capacity building for researchers
and national programs
The Njoro facility plays a major capacity-building role for partner scientists, and MSc and PhD students. CIMMYT trains and equips early career scientists to better prepare them to deal with possible new epidemics, with an annual training targeting 20-25 early-career scientists from across the world. Last year’s training took place on October 1-9, 2018, as part of the Bill & Melinda Gates Foundation- and DFID-funded DGGW project (under the “talent pipeline” objective) managed through Cornell University.
In the last decade, CIMMYT
has trained over 200 scientists from national research programs.
“In addition to imparting
knowledge on new techniques in wheat breeding and genetics,” said Mandeep, “we
normally use such opportunities to train the scientists on evaluating germplasm
for stem rust resistance and standardizing stem rust note taking.”
“With such a partnership, it is
easier and more cost-effective to train our local wheat researchers as opposed
to sending them to all the way to Mexico. We have had a good number of young
scientists trained at this facility as a result of this valuable partnership
with CIMMYT,” said Ruth Wanyera, principal research scientist at KALRO.
programs better prepares them to put improved lines to appropriate use in the
field – a core mandate of CIMMYT accomplished through the Njoro facility.
New varieties deliver essential micronutrients to those who lack diverse diets
This article was originally posted on June 3, 2019 by Mike LISTMAN on cimmyt.org
TEXCOCO, Mexico (CIMMYT) — More nutritious crop varieties developed and spread through a unique global science partnership are offering enhanced nutrition for hundreds of millions of people whose diets depend heavily on staple crops such as maize and wheat, according to a new study in the science journal Cereal Foods World.
From work begun in the late 1990s and supported by numerous national research organizations and scaling partners, more than 60 maize and wheat varieties whose grain features enhanced levels of zinc or provitamin A have been released to farmers and consumers in 19 countries of Africa, Asia, and Latin America over the last 7 years. All were developed using conventional cross-breeding.
“The varieties are spreading among smallholder farmers and households in areas where diets often lack these essential micronutrients, because people cannot afford diverse foods and depend heavily on dishes made from staple crops,” said Natalia Palacios, maize nutrition quality specialist at the International Maize and Wheat Improvement Center (CIMMYT) and co-author of the study.
More than 2 billion people worldwide suffer from “hidden hunger,” wherein they fail to obtain enough of such micronutrients from the foods they eat and suffer serious ailments including poor vision, vomiting, and diarrhea, especially in children, according to Wolfgang Pfeiffer, co-author of the study and head of research, development, delivery, and commercialization of biofortified crops at the CGIAR program known as “HarvestPlus.”
“Biofortification — the development of micronutrient-dense staple crops using traditional breeding and modern biotechnology — is a promising approach to improve nutrition, as part of an integrated, food systems strategy,” said Pfeiffer, noting that HarvestPlus, CIMMYT, and the International Institute of Tropical Agriculture (IITA) are catalyzing the creation and global spread of biofortified maize and wheat.
“Eating provitamin A maize has been shown to be as effective as taking Vitamin A supplements,” he explained, “and a 2018 study in India found that using zinc-biofortified wheat to prepare traditional foods can significantly improve children’s health.”
Six biofortified wheat varieties released in India and Pakistan feature grain with 6–12 parts per million more zinc than is found traditional wheat, as well as drought tolerance and resistance to locally important wheat diseases, said Velu Govindan, a breeder who leads CIMMYT’s work on biofortified wheat and co-authored the study.
“Through dozens of public–private partnerships and farmer participatory trials, we’re testing and promoting high-zinc wheat varieties in Afghanistan, Ethiopia, Nepal, Rwanda, and Zimbabwe,” Govindan said. “CIMMYT is also seeking funding to make high-zinc grain a core trait in all its breeding lines.”
Pfeiffer said that partners in this effort are promoting the full integration of biofortified maize and wheat varieties into research, policy, and food value chains. “Communications and raising awareness about biofortified crops are key to our work.”
For more information or interviews, contact:
International Maize and Wheat Improvement Center (CIMMYT)
How can space technology help improve maize and wheat production? CIMMYT joined a group of international data users in a recent project to find out.
In 2017, a call for proposals from Copernicus Climate Change Service Sectoral Information Systems led the International Maize and Wheat Improvement Center (CIMMYT to collaborate with Wageningen University, the European Space Agency (ESA), and other research and meteorological organizations to develop practical applications in agricultural and food security for satellite-sourced weather data.
The project, which recently ended, opened the door to a wide variety of potential uses for this highly detailed data.
ESA collects extremely granular data on weather, churned out at an hourly rate. CIMMYT researchers, including Foresight Specialist Gideon Kruseman, reviewed this data stream, which generates 22 variables of daily and sub-daily weather data at a 30-kilometerlevel of accuracy, and evaluated how it could help generate agriculture-specific weather and climate data sets.
“For most people, the reaction would be, ‘What do we do with this?’ Kruseman said. “For us, this is a gold mine.”
For example, wind speed — an important variable collected by ESA satellites — is key for analyzing plant evaporation rates, and thus their drought tolerance. In addition, to date, information is available on ideal ago-climatic zones for various crop varieties, but there is no data on the actual weather conditions during a particular growing season for most sites.
By incorporating the information from the data sets into field trial data, CIMMYT researchers can specifically analyze maize and wheat cropping systems on a larger scale and create crop models with higher precision, meaning that much more accurate information can be generated from the trials of different crop varieties.
The currently available historic daily and sub-daily data, dating back to 1979, will allow CIMMYT and its partners to conduct “genotype by environment (GxE)” interaction analysis in much higher detail. For example, it will allow researchers to detect side effects related to droughts and heat waves and the tolerance of maize and wheat lines to those stresses. This will help breeders create specific crop varieties for farmers in environments where the impact of climate change is predicted to be more apparent in the near future.
“The data from this project has great potential fix this gap in information so that farmers can eventually receive more targeted assistance,” said Kruseman.
These ideas are just the beginning of the agricultural research and food security potential of the ESA data. For example, Kruseman would like to link the data to household surveys to review the relationship between the weather farmers experience and the farming decisions they make.
By the end of 2019, the data will live on an open access, user-friendly database. Eventually, space agency-sourced weather data from as far back as 1951 to as recent as five days ago will be available to researchers and weather enthusiasts alike.
Already CIMMYT scientists are using this data to understand the potential of a promising wheat line, for seasonal forecasting, to analyze gene-bank accessions and for a statistical analysis of maize trials, with many more high-impact applications expected in the future.
Crop scientists refute the flawed findings of a study questioning climate resilience in modern wheat breeding.
This article by Marcia MacNeil was originally posted on May 28, 2019 on cimmyt.org.
In early 2019, an article published by European climate researchers in the Proceedings of the National Academy of Science (PNAS) journal questioned the climate resilience of modern wheat varieties. The article suggested that modern wheat varieties showed reduced climate resilience as a direct result of modern breeding methods and practices, a claim that researchers at the International Maize and Wheat Improvement Center (CIMMYT) vehemently rebuke
In a rebuttal letter published in the June issue of PNAS a group of scientists, including CIMMYT’s Susanne Dreisigacker and Sarah Hearne, strongly contradict the finding that breeding has reduced climate resilience in European wheat, citing significant flaws in the authors’ methodology, data analyses and interpretation.
“This article discredits European plant breeders and wheat breeders in general, who have been working over many decades to produce a wide range of regionally adapted, stable varieties which perform well under a broad range of climate change conditions,” said CIMMYT wheat molecular geneticist Susanne Dreisigacker.
Among other flaws, they found a number of omissions and inconsistencies.
The article shows a lack of understanding of commonly used terms and principles of breeding theory, criticizing newer wheat varieties for demonstrating a decrease in “climatic response diversity.” Less diversity in wheat response — that is, more stable yields despite the influence of climate change — is a benefit, not a threat, to farmers.
The article authors contradict the common knowledge among farmers and plant breeders that new elite wheat varieties are generally more productive than older varieties; new cultivars are only approved if they show added value in direct comparison to existing varieties.
The article’s claim of long-term losses of climate resilience in “European wheat” is unsubstantiated. The authors extensively used data from three small countries — the Czech Republic, Denmark and Slovakia — which contribute less than five percent of Europe’s wheat supply. Three of the five most important wheat producers in Europe — Russia, Ukraine and the United Kingdom — were not accounted for in the analysis.
The authors failed to report the actual wheat yields in their study, neglected to publish the underlying data with the manuscript and have up to now declined requests to make the data available.
Europe is one of the world’s major wheat producers and threats to its wheat production due to climate change would have serious consequences for world’s food security. Luckily, say the scientists who published the rebuttal letter, this fear is unfounded.
“Wheat producers and bread consumers around the world will be relieved to learn that breeders have not ignored climate change after all,” said letter lead-author Rod Snowdon, from the Department of Plant Breeding at Justus Liebig University of Giessen, Germany.
The full rebuttal letter by 19 international plant breeders, agronomists and scientists, is available on the PNAS site and reprinted in its entirety below.
Reduced response diversity does not negatively impact wheat climate resilience
Kahiluoto et al. (1) assert that climate resilience in European wheat has declined due to current breeding practices. To support this alarming claim, the authors report yield variance data indicating increasingly homogeneous responses to climatic fluctuations in modern wheat cultivars. They evaluated “response diversity,” a measure of responses to environmental change among different species jointly contributing to ecosystem functions (2). We question the suitability of this measure to describe agronomic fitness in single-cultivar wheat cropping systems. Conclusions are made about “long-term trends,” which in fact span data from barely a decade, corresponding to the duration of a single wheat breeding cycle. The authors furthermore acknowledge increasing climate variability during the study period, confounding their analysis of climate response in the same time span.
The underlying data are not published with the manuscript. Thus, the assertion that there is “no inherent trade-off between yield potential and diversity in weather responses” (1) cannot be verified. Inexplicably, the analysis and conclusions ignore absolute yields, which increase over time through breeding (3–6). Furthermore, incompatible data from completely different ecogeographical forms and species of wheat are apparently considered together, and the dataset is strongly biased toward a few small countries with minimal wheat production and narrow agroclimatic gradients.
The study assumes that increased response diversity among different cultivars is associated with yield stability. In contrast, the common, agronomic definition of yield stability refers to the ability of a single cultivar to stably perform well in diverse environments, without excessive responses to fluctuating conditions. Response diversity measures that ignore absolute yield do not support statements about food security or financial returns to farmers.
Cultivar yield potential, stability, and adaptation are enhanced by multienvironment selection over long breeding time frames, encompassing climate fluctuations and a multitude of other relevant environmental variables. Translation to on-farm productivity is promoted by national registration trials and extensive, postregistration regional variety trials in diverse environments. The unsurprising conclusion that planting multiple cultivars enhances overall production stability mirrors longstanding farming recommendations and practice (7). The availability of robust performance data from a broad range of high-performing cultivars enables European farmers to manage their production and income risks.
Kahiluoto et al. (1) speculate about “genetic erosion” of modern cultivars due to a “lack of incentives for breeders to introduce divergent material.” To substantiate these claims, the authors cite inadequate genetic data from non-European durum wheat (8), while explicitly dismissing clearly opposing findings about genetic diversity in European bread wheat (9). Short-term reductions in response diversity in five countries were misleadingly reported as a “long-term decline” in climate resilience in “most European countries,” although six out of seven countries with sufficient data showed no long-term decline. The article from Kahiluoto et al. and the misrepresentation of its results distorts decades of rigorous, successful breeding for yield potential and stability in European wheat and misleads farmers with pronouncements that are not supported by relevant data.
1 H. Kahiluoto et al., Decline in climate resilience of European wheat. Proc. Natl. Acad. Sci. USA 116, 123–128 (2019).
2 T. Elmqvist et al., Response diversity, ecosystem change, and resilience. Front. Ecol. Environ. 1, 488–494 (2003).
3 S. De Schepper, M. De Loose, E. Van Bockstaele, P. Debergh, Ploidy analysis of azalea flower colour sports. Meded. Rijksuniv. Gent. Fak. Landbouwkd. Toegep. Biol. Wet. 66, 447–449 (2001).
4 I. Mackay et al., Reanalyses of the historical series of UK variety trials to quantify the contributions of genetic and environmental factors to trends and variability in yield over time. Theor. Appl. Genet. 122, 225–238 (2011).
5 F. Laidig et al., Breeding progress, environmental variation and correlation of winter wheat yield and quality traits in German official variety trials and on-farm during 1983-2014. Theor. Appl. Genet. 130, 223–245 (2017).
6 T. Würschum, W. L. Leiser, S. M. Langer, M. R. Tucker, C. F. H. Longin, Phenotypic and genetic analysis of spike and kernel characteristics in wheat reveals long-term genetic trends of grain yield components. Theor. Appl. Genet. 131, 2071–2084 (2018).
7 P. Annicchiarico, “Genotype x environment interactions: Challenges and opportunities for plant breeding and cultivar recommendations.” (Food and Agriculture 201 Organisation of the United Nations, Rome, Italy, 2002), FAO Plant Production and Protection Paper 174.
8 F. Henkrar et al., Genetic diversity reduction in improved durum wheat cultivars of Morocco as revealed by microsatellite markers. Sci. Agric. 73, 134–141 (2016).
9 M. van de Wouw, T. van Hintum, C. Kik, R. van Treuren, B. Visser, Genetic diversity trends in twentieth century crop cultivars: A meta analysis. Theor. Appl. Genet. 120, 1241–1252 (2010).
Efforts to preserve wheat biodiversity help crops, farmers and consumers
For more than 8000 years in an area that now includes Turkey and Afghanistan
hundreds of local varieties — or landraces— evolved to be uniquely adapted to
their environment and ideally suited for local production and consumption. Over the
years, for economic reasons, many farmers have adopted higher-yielding modern
varieties, with only small subsistence farmers in remote areas still growing
ancient landraces. In Turkey, for
example, a 2009 study showed
the share of local landraces was under 1 percent of the total wheat production
Finding, identifying and conserving these local varieties not only safeguards the great biodiversity of wheat in the world, but also helps state of the art efforts to develop resistance to pests and disease, tolerance to environmental stresses and more nutritious wheat.
To complete the cycle, they plan to distribute the seeds of
these improved landraces to farming communities in the target provinces and offer
training on sustainably cultivating their unique landraces to maintain biodiversity
in their fields.
“These landraces are very important to small farmers in
remote mountainous regions,” said Morgunov.
“And they are rich source of genetic traits to fight future threats to wheat
“We are honored to help farmers keep these varieties alive
in their fields.”
Diversity is beneficial for not only wheat health, but human
health as well. A conference this fall in Istanbul
will bring wheat researchers and the health community together to share
progress and discuss strategies for improving the health benefits of wheat
using diverse genetic resources.