导入南瓜DNA选育抗枯萎病西瓜新种质的研究

Study on the Selection of New Watermelon Germplasm for Resistance to Fusarium Wilt Disease by Introducing Pumpkin DNA

采用子房注射法将南瓜总 DNA导入西瓜 ,企望使西瓜和南瓜实现分子水平上的远缘杂交 ,从而获得整合有控制抗病的南瓜 DNA片段而不改变受体西瓜农艺性状的西瓜新种质。用该方法在西瓜自交授粉后 2 4h从子房顶端将 1 5 μl南瓜 DNA注入胚囊中 ,经病圃田间筛选和 6代自交纯化已获得 5份稳定西瓜新材料。经苗期人工接种和病圃田间自然抗病鉴定 ,其抗病性明显提高。所获抗病材料的品质与受体无明显差异。其中 2份材料的果皮色泽和花纹是不同于供受体的新变异类型。试验表明 ,子房注射法将外源 DNA导入西瓜是一种简便实用的分子育种方法 。

The DNA extracted from the pumpkin leaves was introduced into the embryos of watermelon line through embryo injection after self pollination. The aim of this study was that watermelon and pumpkin should be hybridized in molecular level, and the new watermelon germplasm should be obtained having the pumpkin DNA fragments with resistance to fusarium wilt and not altering the agronomic character of receptor watermelon. In this article the 15 μl extracted liquid of pumpkin DNA was injected into receptor watermelon's embryos after self pollination 24 h. Five new watermelon germplasm of resistance to Fusarium oxysporum sp. niveum had been selected by six generation selfing in the wilt disease field. Two of the five watermelon germplasm have new special rind color and strip, which is different from the receptor watermelon′s and the pumpkin′s. The fruits quality of five watermelon varieties obtained by exogenous DNA introducing have no differentiation from the receptor watermelon line's. This study shows that the embryo injection of introducing exogenous DNA was a convenient and practical method, especially on solving the problem of watermelon genetic germplasm being narrow and limited.