Mapping QTL controlling agronomic traits in a doubled haploid population of winter oilseed rape ( Brassica napus L.).

Identification of superior alleles for agronomic traits in genetic resources of oilseed rape ( Brassica napus L.) would be useful for improving the performance of locally adapted cultivars in Iran. The objective of the present work was to analyse the genetic variation and inheritance of important agronomic traits in a doubled haploid population derived from a cross between two German oilseed rape cultivars, Sansibar and Oase. Field experiments were performed in 2016-2017 with 200 doubled haploid lines and the parental genotypes applying an alpha-lattice design with two replicates. Phenological traits were recorded during the cultivation period and at maturity, seed yield, yield components and seed quality traits were determined. Significant genetic variation was found in most of the traits and heritabilities ranged from medium (48.5%) for days to end of flowering to high (92.6%) for oil content. A molecular marker linkage map was used to map 36 QTL for different traits on 17 linkage groups. Between three and four QTL were identified for each seed yield, seed weight, oil and protein content. Some of the plant material and positive QTL alleles identified for agronomic traits may be useful for improving those characters in locally adapted cultivars in Iran.