Mapping of Two Major QTLs Controlling Flowering Time in Using a High-Density Genetic Map.

Research on the flowering habit of rapeseed is important for the selection of varieties adapted to specific ecological environments. Here, quantitative trait loci (QTL) for the days-to-flowering trait were identified using a doubled haploid population of 178 lines derived from a cross between the winter type SGDH284 and the semi-winter type 158A. A linkage map encompassing 3268.01 cM was constructed using 2777 bin markers obtained from next-generation sequencing. The preliminary mapping results revealed 56 QTLs for the days to flowering in the six replicates in the three environments. Twelve consensus QTLs were identified by a QTL meta-analysis, two of which ( and ) were designated as major QTLs. Based on the micro-collinearity of the target regions between and , four genes possibly related to flowering time were identified in the interval, and only one gene possibly related to flowering time was identified in the interval. A tightly linked insertion-deletion marker for the locus was developed. These findings will aid the breeding of early maturing varieties.