Quantitative trait loci analyses for resistance to Sclerotinia sclerotiorum and flowering time in Brassica napus

Sclerotinia stem rot of rapeseed (Brassica napus) has strong negative impacts on seed yield and quality. To elucidate the link between Sclerotinia disease resistance and flowering time in rapeseed, quantitative trait loci (QTL) analyses for resistance against Sclerotinia sclerotiorum and flowering time were carried out in a doubled haploid population derived from a cross between European winter and Chinese semi-winter rapeseed. Six and five QTL for resistance in the field (FR) and under controlled condition (SR) were identified, while 17 QTL were found for flowering time (FT) over 2 years. Among these, four FR QTL, two SR QTL, and three FT QTL clustered within an 8.1-cM region on linkage group C02, which was found to be homeologous with a region on A02 carrying one SR QTL and two FT QTL. The association between Sclerotinia resistance and FT was discussed.