Differential sensitivity to temperature and evaporative demand in wheat relatives

Abstract

Abstract There are potential sources of alleles and genes currently present in wheat-related species that have the potential to be introduced into wheat breeding programs targeting current and future hot and dry climates. However, to date neither the intra- nor the interspecific diversity of the responses of leaf growth and transpiration to temperature and evaporative demand have been investigated in across a significant range of wheat-related species. By analysing 12 groups of wheat-related species and subspecies, we were able to examine the multi-dimensional structure of the genetic diversity for traits linked to plant vegetative structures and their development, and to leaf expansion and transpiration, together with their responses to ‘non-stressing’ ranges of temperature and evaporative demand. In addition to providing new insights on how genome type, ploidy level, phylogeny, and breeding pressure act together to structure this genetic diversity, our study also provides new mathematical formalisms and associated parameters for trait responses across a wide range of genetic diversity in wheat-related species. This will potentially allow crop models to predict the impact of this diversity on yield, and thus to indicate potential sources of varietal improvement for modern wheat germplasms through interspecific crosses.