Quantitative trait loci for grain yield in pearl millet under variable postflowering moisture conditions

Pearl millet marker-assisted selection (MAS) programs targeting adaption to variable postflowering moisture environments would benefit from quantitative trait loci (QTLs) that improve grain yield across the full range of postflowering moisture conditions, rather that just in drought-stressed environments. This research was undertaken to identify such QTLS from extensive (12-environment) phenotyping data set that included both stressed and unstressed postflowering environments. Genetic materials were test crosses of 79 F-2-derived F-4 progenies from mapping population based on widely adapted maintainer line (ICMB 841) x a postflowering drought-tolerant maintainer (863B). Three QTLs (on linkage group [LG] 2, LG 3, and LG 4) were identified as primary candidates for the MAS for improved grain yield across environments, and with QTLs for the harvest index across environments, and with QTLs for both grain number and individual mass under severe terminal stress. Neither had a significant QTL x environment interaction, indicating that their predicted effects should occur across a broad range of available moisture environments. We have estimated the benefits in grain yeild and accompanying changes in yield components and partioning indices that would be expected as a result of incorporating these QTLs into other genetic backgrounds by MAS.