Exploiting increased intraspecific diversity to improve crop response to the abiotic and biotic stressors of climate change

NON-TECHNICAL SUMMARY: Agricultural systems are predicted to be threatened by increasing temperatures, extreme weather events and pest outbreaks associated with climate change. Fundamental research is therefore needed to develop sustainable tactics for adapting to increasing weather- and insect-related crop stress. This project explores the potential of increased crop genotypic, or within-species, diversity to manage plant stress and ensure future crop productivity. We aim to increase within-species diversity by planting mixtures of crop varieties. Ecological evidence from natural and agricultural systems, including our preliminary data, strongly suggests that genotypically diverse cultivar mixtures hold great potential to diminish the influence of climate change by improving plant productivity, insect pest management, and ecosystem resilience. In both the greenhouse and the field, this work will compare the response of variety mixtures of wheat exposed to the stress of drought and plant-feeding insects, in this case aphids, to that of plantings of one variety (monocultures). In addition, we will compare the response of herbivorous and predatory insects to mixtures and monocultures faced with these stressors. We believe that our research will reveal that crop genotypic diversity can provide stress-management and production benefits to grain producers, including protecting and stabilizing yield when crops are confronted with simultaneous stressors. This project will also enhance our understanding of the role interactions between varieties can play in managing plant stress and will help identify mechanisms by which genotypic diversity exerts its influence. Our approach will improve the stress resistance of agroecosystems faced with a changing climate, reducing future reliance on water and pesticide inputs and increasing agricultural sustainability.