Exploration on QTL and SNP Molecular Markers for Oleic Acid Content in Brassica napus Based on Genome-wide Association Analysis
In this study,300 Brassica napus germplasms collected from both domestic and internation-al sources were planted in two environments.By integrating phenotypic and genotypic data of oleic acid content,genome-wide association analysis was conducted using EMMAX software.The results indicated that the distribution of oleic acid content in the associated populations presented a continuous bimodal pattern and was controlled by two major gene loci.GW AS analysis identified a dominant QTL locus regulating oleic acid content,situated between the 53853975 and 57808820 bases of chromosome C03,with a contribution rate of 62.51%.It was correlated with the SNP marker and peak values of chrC03_53853975(A/G)and chrC03_57808820(C/T),and the SNP molecular marker chrC03_56392730(G/T)was closely linked.The corresponding base mutation resulted in polymorphism.When the peak SNP allele was TT,the phenotypic effect value of this trait was 57.93%.This study disclosed for the first time the dominant QTL locus of the C03 chromosome and its SNP molecular marker for the oleic acid content trait of glycole-type rapeseed,with a high contribution rate,provi-ding a crucial theoretical basis for the efficient improvement of this trait and marker-assisted selection.