A differentially methylated region of the ZmCCT10 promoter affects flowering time in hybrid maize.

Flowering time (FT) is a key maize domestication trait, variation in which allows maize to grow in a wide range of latitudes. Although previous studies have investigated the genetic control of FT-related traits per se, few studies of FT hybrid performance have been published. We characterized the genomic architecture associated with hybrid performance for FT in a hybrid panel by testcrossing Chang 7-2 with 328 Ye478 × Qi319 recombinant inbred lines (RILs). We identified 11 quantitative trait loci (QTL) for hybrid performance in FT-related traits, including a major QTL qFH10 that controls hybrid performance and heterosis in a summer maize-growing region. However, this locus acts in regulating FT traits per se only in a spring maize-growing region. We validated ZmCCT10 as a candidate gene for qFH10 and found that differences between hybrids and their parental lines in DNA methylation in the differentially methylated region (DMR, -700 to -1520) of the ZmCCT10 promoter affected gene expression pattern and thereby FT in the summer maize-growing region. [ABSTRACT FROM AUTHOR]