甘蓝型油菜分枝角度QTL定位及候选基因分析

分枝角度是油菜重要株型性状.为筛选和发现适度紧凑的分枝角度调控基因,以提高产量利于机械化收获,以分枝角度差异显著的油菜品种Holly和APL01为亲本构建的重组自交系(RIL)群体为材料,在2个环境中对分枝角度进行QTL定位及候选基因分析.结果表明,RIL群体分枝角度表现出连续变异且呈正态分布.利用前期构建的高密度SN...

QTL mapping and candidate gene analysis of branch angle in Brassica napus L.

Branch angle is important in plant-type traits of rapeseed. For better understand molecular regulation of moderately compact branch angle for high yield and mechanized harvesting, a recombinant inbred line(RIL)population was constructed from Holly and APL01 with significantly different branch angles. Their phenotype of branch angle was investigated in 2 environments. Results showed that branch angles of the RIL population showed continuous variation and normal distribution. QTL mapping analysis was performed using high-density SNP genetic linkage map constructed in previous study. As a result, 8 branch angle QTLs were mapped on chromosomes A9, C3,C4 and C7 respectively. The phenotypic variation explained by a single QTL ranged from 4.05% to 9.60%. Compared with previous studies, 2 new QTLs cqBA.C4-2 and cqBA.C4-3 were stably expressed in the 2 environments,and explained 5.13%-6.80% and 4.60%-7.21% of the phenotypic variation respectively. According to resequencing results of Holly and APL01, a total of 7226 SNPs and 829 InDels were found within cqBA.C4-2 confidence interval(10.32-14.3 Mb), of which 7226 SNPs contained 220 non-synonymous mutations and 5 stop-gain mutations, 15 out of 829 InDels caused frameshift mutations. These mutation sites corresponded to 55 genes. A total of 416 SNPs and 65 InDels were found within cqBA.C4-3 confidence interval(44.39-44.46 Mb), of which 416 SNPs contained50 non-synonymous mutations, 1 out of 65 InDels caused frameshift mutations. And these mutation sites corresponded to a total of 15 genes. According to Arabidopsis homologous genes function annotation, 4 candidate genes related to branching angles were found as BnaC04 g13100 D, BnaC04 g15900 D, BnaC04 g16280 D, and BnaC04 g44330 D. The above results were expected to provide valuable information for revealing regulation of rapeseed branching and cultivating compact rapeseed varieties through molecular design methods.