大豆脂肪含量QTL基因定位及分析OA

Oil content is a crucial quality trait in soybeans,controlled by multiple genes.To locate loci associated with soybean oil content and identify candidate genes,this study used an F2 population consisting of 335 individuals derived from the cross between Qixiaoli 1 and Suinong 76.Genotypic information was obtained using the Zhongdouxin-1 200K SNP array and SSR molecular markers.The oil content of soybean seeds was determined using a Bruker(Germany)MPA near-infrared spectrometer.Genotyping was performed on both the F2 and F3 populations,and quantitative trait locus(QTL)mapping was conducted using the Inclusive Composite Interval Mapping(ICIM)method in IciMapping4.2 software.Candidate genes were screened by integrating data from SoyBase,Phytozome v13.1,and RNA-seq.The results showed that a 454.45 kb mapped interval was identified on chromosome 15 using the F2 population.Using the F3 population for marker densification,this interval was narrowed down to 164 kb,containing 22 genes.One QTL,designated q Oil-15-2,was detected within this 164 kb interval,explaining 6.74％of the phenotypic variation.Analysis of gene expression levels across different tissues(from Phytozome)and transcriptome data led to the identification of four candidate genes:Glyma.15g025800,Glyma.15g026300,Glyma.15g026400 and Glyma.15g026500.These findings provide materials and technical support for map-based cloning of soybean oil-related genes and molecular marker-assisted breeding,and hold significant importance for the directed cultivation of high-oil soybean varieties.