Wheat myth debunked by a major new study

U Queensland Press release

The myth that modern wheat varieties are more heavily reliant on pesticides and fertilisers is debunked by new research published in Nature Plants today.

Lead author on the paper, Dr. Kai Voss-Fels, a research fellow at The University of Queensland, said modern wheat cropping varieties actually out-perform older varieties in both optimum and harsh growing conditions.

"There is a view that intensive selection and breeding which has produced the high-yielding wheat cultivars used in modern cropping systems has also made modern wheat less resilient and more dependent on chemicals to thrive," said Dr. Voss-Fels...




More information: Breeding improves wheat productivity under contrasting agrochemical input levels, Nature Plants (2019). DOI: 10.1038/s41477-019-0445-5 , https://www.nature.com/articles/s41477-019-0445-5

Summary Nature Plants

The world cropping area for wheat exceeds that of any other crop, and high grain yields in intensive wheat cropping systems are essential for global food security. Breeding has raised yields dramatically in high-input production systems; however, selection under optimal growth conditions is widely believed to diminish the adaptive capacity of cultivars to less optimal cropping environments. Here, we demonstrate, in a large-scale study spanning five decades of wheat breeding progress in western Europe, where grain yields are among the highest worldwide, that breeding for high performance in fact enhances cultivar performance not only under optimal production conditions but also in production systems with reduced agrochemical inputs. New cultivars incrementally accumulated genetic variants conferring favourable effects on key yield parameters, disease resistance, nutrient use efficiency, photosynthetic efficiency and grain quality. Combining beneficial, genome-wide haplotypes could help breeders to more efficiently exploit available genetic variation, optimizing future yield potential in more sustainable production systems.


Key Quote

Exploiting genetic potential to improve sustainable productivity

A haplotype-based simulation approach, using haplotype blocks weighted according to their estimated trait variances, facilitated forecasts of genetic potential within our cultivar panel in the context of future sustainable production. Estimated effects of stacking the most beneficial haplotypes for yield under optimum conditions suggested that replacing only 50 detrimental loci in the 20 highest-performing, most recent cultivars could improve grain yield potential by 2.6%, whereas accumulation of the most beneficial haplotypes at all 3,768 genome-wide LD blocks could increase yield potential by up to 23% compared with the best-current elite cultivars. Consideration of haplotype block effects can also facilitate design of complex crosses among complementary genotypes, to enrich breeding progenies with beneficial haplotypes. Induced targeted recombination has potential to facilitate this process in the future. Combining accelerated breeding cycles with haplotype-based genomic selection methods could further accelerate the generation and recognition of superior recombinants to maximize exploitation of the available genetic potential.