【摘要】 以香蕉枯萎病菌 ( Fusarium oxysporum f. sp. cubense) 1号小种和 4号小种及其粗毒素分别接种香牙蕉和粉蕉的组培苗及离体假茎后 ,用组织切片法观察香蕉假茎细胞的病理反应 ,以探明香蕉枯萎病菌不同小种及其粗毒素的致病作用。结果表明 ,枯萎病菌不同小种人工接种仅能感染相应的香蕉种类 ,但不同香蕉种类的离体假茎细胞用不同小种接种及其粗毒素处理 ,均产生褐变等病理反应 ,且病变程度不存在小种间的差异。表明枯萎病菌不同小种对香蕉不同种类的致病力差异可能与存在其它致病因子或专化性识别的因子有关。同时证实了病菌不同小种的毒素对蕉类不存在着选择毒性更多还原

【Abstract】 Banana vascular wilt is a severe disease caused by Fusarium oxysporum f. sp. cubense in south China. This study describes the pathogenic reaction of the banana cells upon the inoculation of spore suspension and crude toxins of F. oxysporum f. sp. cubense. The detached pesudostems and pesudostem cells of banana plantlets were treated with pathogen spores or crude toxin solutions, and the pathogenic reactions were observed by using tissue sectioning. The results showed that the different races of the F. oxysporum f. sp. cubense had their specific host range when the plantlets were inoculated with the fungal spores. However, all the banana cultivars showed the same reactions, such as browning reaction, upon the inoculation of crude toxins produced by different fungal races. This result suggested that the virulence differentiation of F. oxysporum f. sp. cubense was determinated by some unknown factors rather than the toxin specificity. It is also proved that the toxins produced by F. oxysporum f. sp. cubense are non selective for banana.更多还原