新疆棉花黄萎病菌的培养特性及致病力分化

Culture characteristics and pathogenicity differentiation of Verticillium dahliae of cotton in Xinjiang

新疆是我国最主要的棉花生产基地,产量占全国的85%左右。由大丽轮枝菌引起的黄萎病严重阻碍了新疆棉花产业的可持续发展。因此,本研究针对新疆棉区采集分离的140个菌株进行研究,结果发现不同地域菌株的生长速度和产孢量差异显著,新疆棉区以菌核型、落叶型菌株为主;与此同时,建立了一种苗期棉花黄萎病抗性快速鉴定新方法——育苗块定量接种法,并在中植棉2号和新陆早36号上测定了部分菌株的致病力,结果发现新疆棉区以强致病力、中等致病力类型的菌株占主导。此外,落叶型菌株的生长速度、产孢量及致病力均极显著高于非落叶型菌株。结果表明,新疆棉田大丽轮枝菌的组成与分化具有很强的地域性,这对品种的合理布局、抗病性筛选等具有重要意义。

Xinjiang is the most important cotton production base in China,the output accounted for 85%of the country.Verticillium wilt is caused by Verticillium dahliae,which seriously hindered the development of cotton industry in Xinjiang.Therefore,140 isolates collected and separated from cotton region of Xinjiang were stu-died,the results showed that the growth rate and spore production of isolates in different regions were significantly different,and the isolates were predominanted by the sclerotium type and defoliating type.Meanwhile,a new method for rapid identification of cotton seedling resistance to Verticillium wilt was established-seedling block quantitative inoculation method,and the pathogenicity of some isolates was detected on Zhongzhimian 2 and Xinluzao 36,respectively.The results showed that the isolates from cotton region of Xinjiang were dominated by strong and moderate pathogenicity type.In addition,the growth rate,spore production and pathogenicity of the defoliating type isolates were significantly higher than that of the nondefoliating type.All the results showed that the composition and differentiation of V.dahliae in cotton fields of Xinjiang had strong regional characteristics,this is of great significance to the rational distribution of cotton varieties and screening for the disease-resistant varieties.