Genetic Mapping of Grain Shape Associated QTL Utilizing Recombinant Inbred Sister Lines in High Yielding Rice (Oryza sativa L.)
Yiwei Kang·Miao Zhang·Yue Zhang·Weixun Wu·Pao Xue·Xiaodeng Zhan·Liyong Cao·Shihua Cheng*·and Yingxin Zhang*
agronomy
10.3390/agronomy11040705
Abstract
Abstract: Grain shape is a key factor for yield and quality in rice. To investigate the genetic basis of
grain shape in the high-yielding hybrid rice variety Nei2You No.6, a set of recombinant inbred sister
lines (RISLs) were used to map quantitative trait loci (QTLs) determining grain length (GL), grain
width (GW), and length-width ratio (LWR) in four environments. A total of 91 medium/minor-effect
QTL were detected using a high-density genetic map consisting of 3203 Bin markers composed of
single nucleotide polymorphisms, among which 64 QTL formed 15 clusters. Twelve of 15 clusters
co-localized with QTL previously reported for grain shape/weight. Three new QTL were detected:
qGL-7a, qGL-8, and qGL-11a. A QTL cluster, qLWR-12c/qGW-12, was detected across all four environments with phenotypic variation explained (PVE) ranging from 3.67% to 11.93%, which was
subsequently validated in paired lines of F17 progeny and tightly linked marker assay in F10 generation. Subsequently, 17 candidate genes for qLWR-12c/qGW-12 were detected in the 431 Kb interval
utilizing bulk segregant analysis (BSA). Among these, OsR498G1222170400, OsR498G1222171900,
OsR498G1222185100, OsR498G1222173400, and OsR498G1222170500 were the best candidates, which
lays the foundation for further cloning and will facilitate high-yield breeding in rice.