Kernel weight is one of the most important components of grain yield and is controlled by quantitative trait loci (QTLs) derived from natural variations in maize. However, the molecular roles of QTLs in the regulation of kernel weight have not been fully elucidated. In this study, by using homozygous chromosome single segment substitu-
tion lines Z22(SSSL-Z22) as base material, two F
populations derived from a cross between elite maize inbred
line Zheng58 and SSSL-Z22, were employed to map QTLs of kernel weight traits in two years at the same location. Out of four traits, 3 QTLs were detected in one of the two environments whereas 2 detected in both environments. Two major QTLs, qhkw5-3 for hundred-kernel weight and qkw5-3 for kernel width, were consistently detected in similar chromosome segment in different years. qhkw5-3 was mapped to Bin 5.06 flanked by the SSR markers SYM033 and SYM108 with a genetic interval of 8.8 cM, which made kernel size smaller. qkw5-3 was identified between SYM024 and SYM129 with a genetic interval of 13.9 cM. These results will help to promote the fine map- ping and cloning of the target gene and further develop linked markers to be used in marker-assisted breeding
