小麦Mlo反义基因的转化及转基因植株的白粉病抗性分析

Transformation of Antisense Wheat Mlo (Ta-Mlo) Gene and Wheat Powdery Mildew Resistance Analysis of Transgenic Plants

采用基因枪法将小麦反义Mlo基因导入扬麦158和济麦20的幼胚愈伤组织中,在含除草剂的分化培养基上经两轮筛选,获得抗性再生植株。PCR检测、PCR-Southern杂交、基因组DNA斑点杂交和除草剂BASTA抗性分析结果证实已获得转基因扬麦158和济麦20阳性植株,荧光定量表达分析亦证明Mlo基因发生沉默。对T0和T1代转基因植株的白粉病抗性鉴定表明,有6个转基因株系高抗白粉病。对T1代转基因小麦接种白粉菌后孢子发育的显微观察结果显示,Mlo反义基因的导入明显加快了乳突的形成和维持时间,有效抑制了吸器的发育,因而使转Mlo反义基因材料表现抗病性。

The antisense wheat Mlo gene, Ta-Mlo, was transformed into wheat （Tritivum aestivum L.） varieties Yangmai 158 and Jimai 20 via biolistic transformation using immature embryo calli as explants. After two rounds ofbialaphos selection and regen- eration, herbicide-resistant plants were obtained, which were subsequently confirmed by PCR, PCR-Southem hybridization, ge- nomic dot hybridization, and BASTA resistance analysis. The results showed that the Ta-Mlo antisense transgenic Yangmai 158 and Jimai 20 plants were obtained. The real time fluorescence quantitative PCR analysis proved that the transcript of Ta-Mlo was knocked down in these transgenic plants. The disease resistance test showed that the six transgenic lines appeared highly resis- tance to powdery mildew pathogen Blumeria graminis f. sp. tritici （Bgt）. The transgenic lines showed distinct acceleration of the production and stabilization of papillae, and effective suppression to further development of haustoria of Bgt. Therefore, the transgenic lines showed high resistance to Bgt.