转TiERF1-RC7双价基因小麦的鉴定及其全蚀病抗性

Molecular Detection and Take-all Response Assays of TiERF1-RC7 Transgenic Wheat

为探讨TiERF1和RC7基因对小麦抗全蚀病的防御反应,本研究对转TiERF1-RC7双价基因小麦进行了分子检测以及全蚀病抗性的室内和田间鉴定。结果表明,转入的TiERF1和RC7基因在转基因小麦中可以遗传和转录;与受体扬麦18相比,5个转TiERF1-RC7小麦株系在整个生育期抗病性显著提高,苗期的全蚀病严重度在10%以下,成熟期的白穗率在13%以下,而扬麦18的严重度为62.98%,白穗率为26.09%。电子显微镜观察结果表明抗病转基因小麦根表的全蚀病原菌菌丝数量及生长势明显低于感病材料。上述结果说明,转入的TiERF1和RC7基因抑制了全蚀病原菌的侵染及在转基因小麦中繁殖,进而提高了转基因小麦对全蚀病的抗性。

The aim of this study was to understand the role of TiERF1 and RC7 genes in wheat defense response to take-all. Both genes were simultaneously transformed into wheat cultivar Yangmai 18. The resistance to talk-all in five transgenic lines were analyzed by PCR and RT-PCR methods, and evaluated by artificial inoculation in greenhouse and field tests. Scanning electron microscope technique was used to observe the morphology and number of the pathogen mycelia on the root surfaces of resistant transgenic and susceptible receptor wheat plants. The PCR assay showed that both TiERF1 and RC7 genes were integrated into the transgenic lines and inherited to the T3 generation. The RT-PCR assay confirmed expressions of both genes in the transgenic lines. The results showed that five transgenic lines exhibited stable and efficient resistance to take-all with disease severity lower than 10% at seedling stage in greenhouse and rate of white spike lower than 13% at maturity in field. In the contrast of Yangmai 18, the severity was 62.98%, rate of white spike was 26.09%. Electron microscope observation revealed that the number and growth ten- dency of hyphae on roots of the resistant transgenic wheat were significantly lower and weaker than those of the wild type. The expressions of TiERF1 and RC7 inhibit the growth of pathogen hyphae in the transgenic wheat plants, leading to improved resis- tance to take-all.