GUS基因插入导致的小麦条锈菌突变体遗传稳定性和毒性变异研究

 对3个通过基因枪转化GUS基因获得的小麦条锈菌毒性突变体,进行GUS基因的表达活性检测、插入片段DNA的PCR电泳检测和Southern杂交验证;同时用17个国内鉴别寄主和37个黄淮麦区小麦主栽品种对这3个突变菌株进行了毒性谱的测定。结果表明突变菌株的外源GUS基因可稳定遗传;插入的外源基因片段引起了菌株毒性谱的改变。外源基因的插入位点与条锈菌的毒性基因相关。研究还表明插入突变体具有相对的遗传稳定性。研究结果可为克隆小麦条锈菌毒性基因和探明毒性基因的作用机理奠定理论基础。

Hereditary stability and pathogenicity of wheat stripe rust mutants with GUS gene insertion

In the previous study, 3 virulence mutants of wheat stripe rust pathogen, Puccinia striiformis, with GUS insertion were obtained. In this study, expression of GUS gene was analyzed by histochemical staining with X-Gluc, and confirmed by specific PCR and Southern blot. The results indicated that the alien gene GUS was integrated and could inherit stably in the stripe rust genome. The pathogenicity of the 3 mutants on 17 wheat stripe rust differentials and 37 extension cultivars was different from that of the wild isolate. The inserted alien fragment resulted in the pathogenic variation of the mutants. The insertion sites of foreign gene were relevant to the virulent gene of Puccinia striiformis. This study provides a basis for the cloning of the avirulent genes.