【摘要】 1983年对江苏棉花黄萎病原菌 Verticillivm dahliae Kleb.95个分离菌株培养条件测定结果,28℃是适宜生长的临界温度,PH7下菌落生长较旺,PDA上菌丝体生长好于CAA上,但菌核形成后者较佳。1985—1987年,在5个棉花品种上致病力测定结果,根据病情指数可分成强、中、弱三个致病型,全省或一个地区乃至同一块病田采集的菌株,亦有致病力的差异。Ⅱ型菌系为多数,占供测菌株数的62.8％,强致病力菌系中有落叶型菌株的存在。更多还原

【Abstract】 The colonies of Verticillium dahliae Kleb, causing verticillium wilt of cotton in Jiangsu Province were found to grow best at 22-28℃ and pH7 in experiments with 95 isolates in 1983.The mycelia grew better on PDA medium than on CAA, but the situation was just opposite for sclerotial formation.Based on tests of the collected pathogen isolates on 5 cotton varieties in 1983-1987, the isolates were divided into 3 types in terms of disease index (D.Id. ) and symptom reaction.Type I, had strong pathogenicity, causing symptoms from blighted leaf spots to defoliation; type II, intermediate pathogenicity, from watermelon- rind- like streaks to blighted leaf spots; type III, weak pathogenicity, mostly causing yellow leaf spots. Difference in pathogenicity could be found among isolates collected from the same district or even the same field. Most of the isolates investigated were grouped in type II, making up 62.80% of the total.更多还原