Detection of quantitative trait loci (qtl) associated with yield and yield component traits in sorghum [Sorghum bicolor (L.) Moench] sown early and late planting dates

Abstract

Genetic improvement for grain yield is one of the challenges in plant breeding programs. QTL analysis is often used to dissect complex trait like grain yield for a better genetic manipulation. The purpose of this study was to map QTLs associated with yield and yield component traits of sorghum grown under early and late planting dates. A total of 528 recombinant inbred lines (RILs) and their two parents were sown early and late planting times in an augmented rectangular lattice block design with two replications to generate field phenotypic data. A total of 379 markers consisting of DArT, SSR and morphological markers were used to genotype the RILs and the parents. Results revealed the presence of overall twelve QTL across traits and planting dates. More QTLs were detected for grain yield as compared to each of the other traits and most QTL associated with grain yield were consistent across planting dates while QTL associated with yield component traits were not. Stable QTLs detected in this study might provide valuable information in breeding sorghum for enhanced grain yield in diverse growing environment.