Crop wild relatives that have survived changing climates for millions of years may provide the solution to adapting wheat, humanity’s most widely grown crop, to climate change. Two new studies led by the International Maize and Wheat Improvement Center (CIMMYT) reveal how tapping into this ancient genetic diversity can revolutionize wheat breeding and safeguard global food security.
As the weather becomes more erratic and extreme, wheat — providing 20% of all calories and protein globally and serving as the primary staple food for 1.5 billion people in the Global South — faces unprecedented threats. These include heat waves, delayed rains, flooding, and new pests and diseases.
“We’re at a critical juncture,” says Dr. Matthew Reynolds, co-author of both studies. “Our current breeding strategies have served us well, but they must now address more complex challenges posed by climate change.”
The research points to a vast, largely untapped reservoir of nearly 800,000 wheat seed samples stored in 155 genebanks worldwide. These include wild relatives and ancient, farmer-developed varieties that have withstood diverse environmental stresses over millennia. Although only a fraction of this genetic diversity has been utilized in modern crop breeding, it has already delivered significant benefits.
Proven impacts of wild wheat genes
One of the studies, a review published today in Global Change Biology (GCB)*, documents the immense impact of wild relatives’ traits, including on environmental sustainability. It finds that the cultivation of disease-resistant wheat varieties has avoided the use of an estimated 1 billion liters of fungicide just since 2000.
“Without transferring disease-resistant genes from wild relatives to wheat, fungicide use would have easily doubled, harming both human and environmental health,” says Dr. Susanne Dreisigacker, Molecular Breeder at CIMMYT and co-author of the review.
Sharing of new wheat breeding lines through the CIMMYT-led International Wheat Improvement Network, comprising hundreds of partners and testing sites around the world, increases productivity worth USD 11 billion of extra grain every year. The extra productivity has saved millions of hectares of forests and other natural ecosystems from cultivation.
The review highlights other key breakthroughs using wheat wild relatives, including:
- Some experimental wheat lines incorporating wild traits show up to 20% more growth under heat and drought conditions compared to current varieties.
- Genes from a wheat wild relative have generated the first crop ever bred to interact with soil microbes, reducing the production of nitrous oxide, a potent greenhouse gas, and enabling the plants to use nitrogen more efficiently.
- New, high-yielding cultivars in Afghanistan, Egypt and Pakistan were developed using wild genes and have been released as they are more robust to the warming climate.
“Breeding the first beneficial interaction with the soil microbiome — in this case biological nitrification inhibition, or BNI-wheat — is a landmark achievement by CIMMYT and JIRCAS, opening up a whole new spectrum of opportunities to boost cropping systems’ resilience and reduce environmental footprints,” says Victor Kommerell, co-author of the GCB review, and Director of CropSustaiN, a new research initiative to determine the global climate mitigation and food security potential of BNI wheat.
The second study in Nature Climate Change* showcases the urgent need to scale-up exploration and use of genetic diversity for improved climate resilience. Among the traits needed are deeper, more extensive root systems for better water and nutrient access; photosynthesis that performs well across a wider temperature range; better heat tolerance in reproductive processes; and improved survival during delayed rains or temporary flooding.
“Tapping into the complex climate-resilient traits so urgently needed today requires both access to greater genetic diversity and a paradigm shift in breeding approaches,” explains co-author of the GCB review, Dr. Julie King of Nottingham University.
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