New stress index identifies hormones as a key physiological trait for resilience to heat and drought

WJ Davies, A Thiry and X Li

Lancaster University, LA1 4YQ, UK

Global warming and the increased food demand by a growing world population, mean that we must speed up the selection of crop genotypes resistant to and productive under abiotic stress. Cereal breeding selection for adapted genotypes to stress environments relies principally on yield testing. However, crop production under stress is a compromise of resilience and the production capacity of the genotypes and information on these variables would be useful to breeders. The basis of tolerance to a stress environment is not clear and oscillates between the concept of yield stability and high production under both environments. In this work, a new method for evaluation of genotypes in terms of resilience to face the stress and production capacity is suggested. Our stress indices have been applied to identify a relationship between hormones (ABA and Ethylene) and drought stress resilience of a wheat crop at a key phenological stage. The results suggest that hormones could be used as a new physiological trait to identify genotypes with high resilience in term of spike fertility and other key developmental variables.