QTL identification and meta-analysis for kernel composition traits across three generations in popcorn

Abstract

Dissecting the genetic controls of kernel composition traits would provide important information for improving popcorn’s quality. In this research, a recombinant inbred lines (RILs) population with 258 RILs was evaluated to detect quantitative trait loci (QTLs) for 4 kernel composition traits (CT, starch concentration; CP, protein concentration; CF, oil concentration; LS, lysine concentration) under three environments. As a result, 23 QTLs associated with the 4 kernel component traits were identified. Four QTLs at bins 3.04, 3.04, 4.01 and 5.03–5.04 were consistently detected in the similar chromosome locations. Three QTLs at bins 1.07–1.08, 3.04 and 6.07 were commonly detected in the same or nearby bins across three generations (RIL, F2:3 and BC2F2) derived from the same cross. A meta-analysis was conducted to integrate QTLs detected across three generations. Fifteen meta-QTLs were detected except on chromosomes 8 and 10. Three chromosome locations (bins 3.04, 4.01 and 5.03–5.04) with higher contribution to kernel composition traits showed no relation with the QTLs identified for popping characteristics. Three chromosomal regions could be further used to improve of maize kernel quality and to enhance popcorn quality.