基于WGS构建葡萄高密度遗传图谱及抗炭疽病QTL定位

Construction of Grapevine Genetic Map Based on WGS and Positioning QTL for Resistance to Ripe Rot

葡萄炭疽病是一种危害葡萄成熟果实的真菌病害,严重影响葡萄的产量和品质。美洲种葡萄具有适应南方湿热气候且高抗炭疽病的特点,因此构建美洲葡萄高密度分子遗传图谱,定位其抗炭疽病QTL,利用其中的抗病基因指导葡萄抗病育种具有重要意义。本研究以美洲葡萄‘C30-5-1’165株自交后代为作图群体,基于全基因组测序(WGS)开发SNP标记,构建遗传图谱,并对葡萄抗炭疽病QTL进行分析。构建的葡萄分子遗传图谱总遗传距离为3138.74 cM,相邻标记间平均遗传距离为0.98 cM,分布均匀。根据群体炭疽病抗性表型数据,在11号连锁群上检测到1个炭疽病抗性相关QTL,命名为Cgr2,可解释表型变异5.0%,是一个微效QTL。与葡萄参考基因组比对分析发现,该QTL区域包含2个候选抗性基因,分别编码UDP糖基转移酶和类黄酮3’-单加氧酶,它们可能对葡萄炭疽病抗性起重要作用。

Grape ripe rot is a kind of fungal disease which harms ripening fruit and seriously affects grape yield and quality.American grape has characteristics of adapting to humid and hot climate in south area and high resistance to ripe rot.Therefore,it is of great significance to construct a high-density molecular genetic map of American grape,locate its QTL for resistance to ripe rot,and use the disease resistance gene to guide grape disease resistance breeding.In this study,165 self-inbred offsprings of American grape‘C30-5-1’were used as the mapping population,based on whole genome resequencing(WGS),the genetic map was constructed,and the ripe rot resistance QTL of grapes was analyzed.The total genetic distance of the constructed grape molecular genetic map was 3138.74 cM,and the average genetic distance between adjacent markers was 0.98 cM,which was evenly distributed and good quality.Based on the offspring ripe rot resistance phenotypic data,a ripe rot resistance-related QTL was detected on the 11th linkage group,named Cgr2,which micropotent QTL explained 5.0% phenotypic variation.After comparison analysis with the grape reference genome,the QTL region contained two candidate resistance genes which encoded UDP glycosidyltransferase and flavonoid 3'-monooxygenase,respectively.They might provide an important role for resistance to ripe rot in grapevine.