Genetic dissection of stay-green and other traits related to dry land spring wheat performance

Abstract

Spring wheat production in the upper Great Plains is at risk due to increased occurrence of low moisture and high temperatures during grain-fill. Wheat yield is impacted by several often counteracting traits, including seed number per head, seed weight and number of productive tillers. A variety of morphological and phenological plant characteristics impact performance in conditions of low moisture and high temperatures during grain-fill. In this study, we dissect traits associated with grain yield using a recombinant inbred line (RIL) mapping population derived from parents with contrasting phenotypes for several yield and drought related traits. Importantly, differences in quantitative trait loci (QTL) for yield and yield components were observed in the RIL between rain-fed and irrigated environments. We report important QTLs associated with yield and drought stress in spring wheat, with the long term goal of identifying traits useful to molecular breeding programs for the creation of lines better adapted to our changing environments. We also confirmed six grain-fill QTLs in association mapping (AM) panel which were identified by using this RIL population.