Genetic dissection of drought and heat-responsive agronomic traits in wheat
作 者：Long Li, Xinguo Mao, Jingyi Wang, Xiaoping Chang, Matthew Reynolds, Ruilian Jing
刊物名称：Plant, Cell & Environment
出版年份：06 May 2019
文章摘要：High yield and wide adaptation are principal targets of wheat breeding, but are hindered by limited knowledge on genetic basis of agronomic traits and abiotic stress tolerances. In this study, 277 wheat accessions were phenotyped across 30 environments with non-stress, drought-stressed, heat-stressed and drought-heat-stressed treatments, and were subjected to genome-wide association study using 395,681 SNPs. We detected 295 associated loci including consistent loci for agronomic traits across different treatments and eurytopic loci for multiple abiotic stress tolerances. A total of 22 loci overlapped with QTL identified by biparental QTL mapping. Six loci were simultaneously associated with agronomic traits and abiotic stress tolerance, four of which fell within selective sweep regions. Selection in Chinese wheat has increased the frequency of superior marker alleles controlling yield-related traits in the four loci during past decades, which conversely diminished favorable genetic variation controlling abiotic stress tolerance in the same loci; two promising candidate paralogous genes colocalized with such loci, thereby providing potential targets for studying the molecular mechanism of stress tolerance-productivity trade-off. These results uncovering promising alleles controlling agronomic traits and/or multiple abiotic stress tolerances, providing insights into heritable covariation between yield and abiotic stress tolerance, will accelerate future efforts for wheat improvement.