title: Colocalization of a partially dominant gene for yellow seed colour with a major QTL influencing acid detergent fibre (ADF) content in different crosses of oilseed rape (Brassica napus).
abstract: Quantitative trait loci (QTLs) contributing to yellow seed colour and acid detergent fibre (ADF) were localized and compared in 3 mapping populations developed from 2 crosses (designated 'YE1' and 'YE2') between 2 distinct sources of true-breeding yellow-seeded oilseed rape (Brassica napus) and 2 different black-seeded genotypes. A clear correlation was observed between seed colour and ADF content in both crosses. In all 3 populations, a major QTL, with a large effect on both seed colour and ADF in multiple environments, was detected at the same position on chromosome N18. In YE1, a second minor QTL, with a small effect on seed colour but not on ADF content, was localized on chromosome N1. In YE2, no QTL was observed on N1; however, 2 minor seed-colour loci were localized to N15 and N5. A second major QTL for ADF was localized in YE1 on N13; in YE2, no other QTLs for ADF were detected. Combined QTL and segregation data for seed colour and ADF content in the different populations suggest that a partially dominant B. napus gene for seed colour on N18 contributes to a reduction in fibre content in different yellow-seeded B. napus genotypes. The other QTLs that were identified appear to represent different genes in the 2 yellow-seeded rapeseed sources, which, in each case, affect only fibre content or seed colour, respectively. Potential candidate genes and implications for marker-assisted breeding of oilseed rape with reduced seed dietary fibre content are discussed.
authors.affiliation: Department of Plant Breeding, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, Heinrich-Buff-Ring 26-32, D-35392 Giessen, Germany.
authors.forename: Ana Gloria
authors.initials: AG
authors.lastname: Badani
authors.forename: Rod J
authors.initials: RJ
authors.lastname: Snowdon
authors.forename: Benjamin
authors.initials: B
authors.lastname: Wittkop
authors.forename: Florin D
authors.initials: FD
authors.lastname: Lipsa
authors.forename: Roland
authors.initials: R
authors.lastname: Baetzel
authors.forename: Renate
authors.initials: R
authors.lastname: Horn
authors.forename: Antonio
authors.initials: A
authors.lastname: De Haro
authors.forename: Rafael
authors.initials: R
authors.lastname: Font
authors.forename: Wilfred
authors.initials: W
authors.lastname: Lühs
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Friedt
mesh_terms: D029688:Brassica napus / Q000737:chemistry / Q000235:genetics*; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D004043:Dietary Fiber / Q000032:analysis; D005799:Genes, Dominant; D018598:Minisatellite Repeats; D010858:Pigmentation / Q000235:genetics*; D010940:Plant Proteins / Q000032:analysis* / Q000235:genetics*; D040641:Quantitative Trait Loci; D012639:Seeds / Q000235:genetics
chemical_list: D004043:Dietary Fiber; D010940:Plant Proteins