穗长是影响水稻(Oryza sativa)产量的重要因子之一, 研究水稻穗长QTL间的上位性效应对于发掘水稻产量潜力具有重要意义。该研究以16个单片段代换系(single segment substitution lines, SSSLs)和15个双片段聚合系(double segment pyramiding lines, DSPLs)为材料研究了水稻穗长QTL的加性及上位性效应。以P<0.01为阈值, 共检测到6个穗长QTL和9对基因互作座位。其中2个(Pl-2和Pl-10)是尚未报道的穗长QTL。穗长QTL互作后, 一些互作对的上位性效应与单个QTL的作用方式及效应大小各不相同, 预示着基因聚合后会产生不同的互作效应。该研究结果对于通过分子聚合育种手段改良穗长具有重要意义。

Panicle length is one of the important factors influencing rice yield. In rice breeding, study of quantitative trait loci (QTL) of panicle length and their epistasis effects in rice is important. In this study, we used 16 secondary single segment substitution lines and 15 double segment pyramiding lines with a Huajingxian 74 background as mapping populations to study QTL for panicle length and their gene interactions. We detected 6 QTLs for panicle length, of which 2 (Pl-2 and Pl-10) were previously unreported. Furthermore, after interactions, some loci pairs had different effect strength and opposite direction of each locus, which indicated that the gene pyramiding may result in various interaction patterns. These results are important for improving rice panicle length with molecular marker-assisted breeding.