西瓜回交世代酸味株系基因型分析

Genotype analysis of watermelon with sour flesh in BC_7F_1 population

有机酸的组分与含量是影响西瓜果实品质的重要因素,对果实的营养品质和代谢起重要作用。本试验以野生种西瓜‘PI 271769’为供体亲本,栽培种西瓜‘203Z’为轮回亲本进行高代回交,在BC7F1世代发现了果实变酸的材料。通过SSR分子标记和图示基因型软件GGT对酸味株系进行基因型分析,发现有2~4个含有供体亲本的外源片段,推测外源片段上存在与有机酸合成途径相关的关键基因。研究结果为有机酸合成途径关键基因的精细定位和克隆提供了良好的试验材料,同时也丰富了西瓜的种质资源类型,有助于选育酸甜风味的西瓜新品种。

Composition and content level of organic acids are key factors to the fruit quality of watermelon, and play an important part in nutrition quality and metabolism. In this study, the BC_7F_1 population was constructed using‘PI 271769＇（known to have different characters compared to the recurrent parent）as donor parent, and the elite watermelon cultivar‘203Z＇as recurrent parent, and we found that some watermelon of BC_2F_1 population have sour flesh. The genotype of watermelon with sour flesh was analyzed by simple sequence repeat（SSR）markers and Graphical Geno Types（GGT）, there were 2-4 exogenous segments derived from the donor parent, which were predicted to associated with key genes of organic acids synthetic.These results provide good experiment materials for fine mapping and map-based cloning of key genes associated with organic acids synthetic, and enrich germplasm resources of watermelon, which contribute to breeding new variety of watermelon with sour and sweet taste.