Genome-wide molecular mapping and QTL analysis, validated across locations and years for charcoal rot disease incidence traits in Sorghum bicolor (L.) Moench

To assess the stability of QTLs across environments and years and to identify the stable QTL influencing the disease incidence, 93 RILs derived from charcoal rot resistant (E 36-1) and susceptible (SPV 86) parents of sorghum (Sorghum bicolor L.) were used to phenotype over locations and years to find genetic architecture of charcoal rot disease through QTL mapping. A total of 141 polymorphic marker (48/275 SSRs, 28/410 RAPD, 65/533 gSSRs) loci were mapped onto 10 linkage groups, with an average interlocus distance of 19 cM, and total genetic map length of 2905 cM. Composite interval mapping (CIM) with peak threshold of 2.0 was considered for QTL detection. A total of nine stable quantitative trait loci (QTL) for morphological trait along with three QTLs for biochemical trait influencing charcoal rot disease incidence were detected.