title: Characterization of the quantitative trait locus OilA1 for oil content in Brassica napus.
abstract: Increasing seed oil content has become one of the most important breeding criteria in rapeseed (Brassica napus). However, oil content is a complex quantitative trait. QTL mapping in a double haploid population (SG population) emerging from a cross between a German (Sollux) and Chinese (Gaoyou) cultivars revealed one QTL for oil content on linkage group A1 (OilA1), which was mapped to a 17 cM genetic interval. To further validate and characterize the OilA1, we constructed a high-resolution map using B. rapa sequence resources and developed a set of near-isogenic lines (NILs) by employing a DH line SG-DH267 as donor and Chinese parent Gaoyou as recurrent background. The results showed highly conserved synteny order between B. rapa and B. napus within the linkage group A1 and revealed a possible centromere region between two markers ZAASA1-38 and NTP3 (2.5 cM). OilA1 was firstly validated by 250 BC5F2 plants and was confirmed in a 10.6 cM interval between the markers ZAASA1-47 and ZAASA1-77. Further substitution mapping was conducted by using two generations of QTL-NILs, 283 lines from eight BC5F3:4 families and 428 plants from six BC5F4 sub-NILs and thus narrowed the OilA1 interval to 6.9 cM and 4.3 cM (1.4 Mb), respectively. Field investigations with two replications using homozygous BC5F3:4 sister sub-NILs indicated that NILs, which carry a Sollux chromosome segment across the target region showed significant higher oil content (1.26 %, p < 0.001) than their sister NILs containing Gaoyou chromosome. The OilA1 locus is of particular interest for breeding purpose in China because 80 % of Chinese cultivars do not carry this desirable allele.
authors.affiliation: Institute of Crop and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
authors.forename: Yubo
authors.initials: Y
authors.lastname: Chen
authors.forename: Lu
authors.initials: L
authors.lastname: Qi
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Zhang
authors.forename: Jixiang
authors.initials: J
authors.lastname: Huang
authors.forename: Jibian
authors.initials: J
authors.lastname: Wang
authors.forename: Hongcheng
authors.initials: H
authors.lastname: Chen
authors.forename: Xiyuan
authors.initials: X
authors.lastname: Ni
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Dong
authors.forename: Haiming
authors.initials: H
authors.lastname: Xu
authors.forename: Jianyi
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000483:Alleles; D029688:Brassica napus / Q000235:genetics*; D003433:Crosses, Genetic; D017343:Genes, Plant / Q000235:genetics*; D005819:Genetic Markers; D005838:Genotype; D007178:Inbreeding; D020161:Physical Chromosome Mapping; D010938:Plant Oils / Q000378:metabolism*; D040641:Quantitative Trait Loci / Q000235:genetics*; D015203:Reproducibility of Results
chemical_list: D005819:Genetic Markers; D010938:Plant Oils