新疆几株黄萎轮枝菌株的形态学鉴定与生物学特征特性比较研究

The Comparison of the Morphological and Biological Characteristics of Several Verticillium Strains in Xinjiang

采集新疆南北棉区的棉花症状表现为黄斑型和落叶型的以及从茄与苍耳上分离得到的黄萎轮枝菌共6个菌株,进行了形态学及生物学特征特性的比较研究。结果表明,6菌株都无形态学上的显著差异,其生物学特征特性也基本雷同。6个菌株同在棉、红花、向日葵、茼麻、苍耳和辣椒上作交互接种,均表现为不侵染辣椒,但对其他的6种供试植物均持不同程度的致病力现象。以茄菌与苍耳菌对供试的6种植物的致病力都强,而寄生在棉花上的4个菌株除对其原寄主的致病力为中、强度外,对红花、向日葵、苍耳及苘麻的致病力也强,但对茄的致病力则弱,或无致病能力。本试验6个菌株均应被鉴定为大丽花轮枝菌(Verticillium dahliaeKleb.),但从其全部的表现形式看仍有较明显的生理分化现象。从棉花上的4个菌株表现的形式可以看出,南北疆棉黄萎病的黄斑型与落叶型分离物均同属于中、强度侵染的致病菌,在许多情况下,黄斑型菌株的致病力还往往强于落叶型菌株的致病力,从当前南北疆棉区的棉花黄萎病中表现有落叶型反应的病株,很难断定为系属强致病力变异菌株的症状反应。

From different northern and southern regions of Xinjiang,we collected 6 representative strains in cotton, eggplant,and cocklebur samples with yellow spotted typical and defoliating typical vertieillium. The morphological and biological characteristics of these verticillium strains were studied and classified. The results show that there are no obvious morphological distinctions among these strains and the biological characteristics are also similar to each other. The artificial inoculation on cotton, eggplant,safflower, sunflower,piemarker,cocklebur and chili pepper were conducted respectively with these strains. The resuits showed that all the 6 representative strains could not infect chili pepper, but had different pathogenicity to other 6 vegetable plants. The strains from the eggplant and Siberian cocklebur had significant pathogenicity to other 6 vegetable plants; while the four strains from the cotton appeared to have major pathogenicity to its own plants as well as to piemarker, safflower, sunflower, cocklebue and chili pepper, but had only minor （or no） infective capability to eggplant. Based on these results, the 6 collected strains could be identified as Verticillium dahliae kleb, and they displayed distinct physiological differential appearance. According to field actual experimental results, the 4 strains from the cotton, either spotted typical strain or defoliating typical one, could be categorized as major infection-causing type. But in certain circumstance, the spotted typical strain had larger infection-causing capability than the defoliating typical strain.Therefore, the cotton verticillium with the defoliating typical strain in Xinjiang may not be classified as the type with major infection-causing capability.