Study: Plant secondary metabolite-dependent plant-soil feedbacks can improve crop yield in the field
1 August 2023
In this work led by Valentin Gfeller, we studied the agronomic relevance of secondary metabolite mediated plant soil feedbacks. Plants secrete secondary metabolites from their roots to soil to alter the biotic and abiotic properties and this affects the performance of the next generation of plants. From greenhouse experiments we knew that maize-exuded benzoxazinoids impact the performance of wheat and here, we tested if these feedbacks occur in ‘real life’, i.e. in crop rotation in the field. We assessed three winter wheat varieties growing in field plots whose soils had been conditioned by either wild-type or benzoxazinoid-deficient maize plants. Following maize cultivation, we detected benzoxazinoid-dependent chemical and microbial changes in the soil, increase wheat biomass and also decreased insect herbivore abundance in benzoxazinoid-conditioned soils. Importantly, yield was increased by over 4% without a reduction in grain quality in benzoxazinoid-conditioned soils. Taken together, here we show that soil conditioning with plant secondary metabolites can increase yield via plant-soil feedbacks under agronomically realistic conditions. Hence, if these feedbacks function across different soils and environments, optimizing root exudation chemistry could be a powerful strategy to enhance crop yields without additional inputs. mehr
