西昌地区石榴叶霉病的病原鉴定

A new pomegranate disease—identification of the pathogen causing the pomegranate leaf mold disease

本文报道了四川西昌市发生的石榴叶霉病的症状及病原鉴定结果。叶霉病发生在石榴生长后期,一般危害石榴老叶,表现为黑褐色病斑,造成石榴提早落叶。病原分离采用组织分离法,通过分生孢子悬浮液接种,用柯赫氏法则对其致病性进行验证。显微镜下观察菌丝形态及产孢结构,测量孢子大小,根据形态特征鉴定为极细枝孢(Cladosporium tenuissimum Cooke)。

Leaf mold is a new disease that usually infects old leaves at later stages of development, then forms necrotic spots and leads shedding of the immature fruits. In this study, infected leaves of Punica granatum in the growing region of Xiaomiao village in Xichang were coUected. The pathogens were isolated and tested immediately according to the standard Koch＇s postulation methods. Then the isolates were micro-examined, measured, described and mapped out. The results revealed that it was Cladosporium tenuissimum Cooke that caused leaf mold in the P. granatum leaves.