Validation of QTL for Grain Yield-Related Traits on Wheat Chromosome 3A Using Recombinant Inbred Chromosome Lines

Previously, quantitative trait loci (QTLs) for grain yield (GYLD) and yield-related traits were identified by using a population of recombinant inbred chromosome lines (RICLs) developed from the wheat (Triticum aestivum L.) cultivar Cheyenne (CNN) and its substitution line CNN(WI3A), in which the 3A chromosome of cultivar Wichita (WI) was substituted for CNN chromosome 3A. Our objectives were to identify and validate the QTL previously identified in CNN(RICLs3A), using the mirror population WI(RICLs3A). A population of 90 WI(RICLs3A) was used to evaluate GYLD, 1000-kernel weight (TKW), kernels per spike (KPS), kernels per square meter (KPSM), spikes per square meter (SPSM), grain volume weight (GVW), plant height (PHT), and anthesis date (AD). Data were collected from replicated trials grown in six Nebraska environments from 2008 to 2009. Twelve QTL for GYLD, TKW, KPS, SPSM, GVW, AD, and PHT were detected. The phenotypic variance explained by these QTL ranged from 12% for SPSM to 53% for GVWT. Most of the QTLs were co-localized in one or two regions of chromosome 3A. The major grain yield QTL (QGyld.neb.3A.1) detected in the combined analysis explained 19% of the phenotypic variance and the substitution of CNN alleles for WI alleles decreased grain yield. Using a different genetic background, this study confirmed most of the GYLD and yield-related QTL reported in previous RICLs3A mapping studies on chromosome 3A of winter wheat evaluated in Nebraska.