QTL for plant structure type and their influence on seed-related traits in wheat

Abstract

Plant structure type (PT) is an important complex and quantitative trait to regulating yield potential and stress tolerance in wheat (Triticum aestivum L.). In this study, a recombinant inbred line (RIL) population genotyped by wheat 50 K SNP chip was employed to detect quantitative trait loci (QTL) controlling plant structure type and seed-related eight traits in seven environments. A total of 13 QTL were detected in multiple environments. By comparing previous studies, QKw-5D-2-2 (kernel width) and QSnl-6B (spike neck length), on chromosomes 5D and 6B, respectively, were regarded as two new multi-environmental stable QTLs explaining 5.01–11.51% and 9.79–15.01% of the phenotypic variation, correspondingly. In addition, we predicted two genes associated with grain width in the interval QKw-5D-2-2, and seven multi-environmentally stable QTLs on chromosome 4D were found to be distributed in clusters; significant correlations were found between plant height (PH) and, PT, spike neck length (SNL), basal two internode length (BL), kernel width (KW) and thousand kernel weights (TKW) by genetic and correlation analyses. In summary, our results will provide help to understand the genetic relationship between plant structure type and yield potential. And the newly identified QTLs and QTL clusters lay the genetic foundation for fine localization of plant structure type related traits and molecular marker-assisted breeding in wheat genetic improvement.