Lack of GM in wheat puts global crop at risk

Genetic modification of wheat for disease resistance could help stabilise global food production if the will can be found to make it happen, two crop geneticists have suggested.

Writing in the journal Science, Brande Wulff, from the John Innes Centre in Norwich, UK, and Kanwarpal Dhugga from Mexico’s International Maize and Wheat Improvement Centre, say the recent devastating impact of a disease called wheat blast in Asia is just one example of a crisis GM might have helped curtail.

Already entrenched in South America, wheat blast emerged in Bangladesh in 2016 and now threatens all of South and Southeast Asia, the world’s largest wheat belt.

Cloning multiple blast-resistant genes found in wild wheat varieties and inserting them into the genome of commercial cultivars could substantially delay the evolution of defence-beating pathogens, the authors believe. However, they don’t see that happening any time soon.

“Wheat, a worldwide staple food, has become an orphan among genetically modified crops,” they write.

The “genetic treasure trove” for disease resistance, as they term it, in wild wheat remains a largely under-utilised resource for breeding.

Wulff and Dhugga say wheat is a low-priority for GM research despite the success of other GM crops such as corn, cotton and soy beans, as well as promising trials with rice. 

And yet across the globe wheat is grown on more land area than any other cereal crop and provides about 20% of the daily calories and protein per capita worldwide.

Pressure from anti-GM consumer groups is one of the reasons why the cereal remains unmodified, but there are others.

“Wheat is grown mostly on marginal land in the United States and generates only about 20% of farm income compared with maize,” the authors note, “making it questionable whether industry can recover the costs associated with research investment.”

However, they believe it is worth making the effort, because countries in Africa and Asia, where food security is a perpetual concern, might be receptive to GM wheat, provided its use helps to stabilise production.

They concede that it will not be an easy task, as a range of factors conspire to limit the scope of traditional gene-cloning technologies, but note that new technologies are likely to fuel an exponential growth of cloned, disease-resistance genes.