作　　者： ; ; ; ;

机构地区： 华中农业大学食品科学技术学院

出　　处： 《长江蔬菜》 2011年第16期68-72,共5页

摘　　要： 分别用组织分离法、直接挑取法和组织浸液划线法对贮藏期患病莲藕的病原菌进行分离,分离得到9种真菌,经回接发现9种真菌均致病。再通过形态学鉴定,初步确定9种真菌中有3种分别属于青霉属(Penicillium)、交链孢霉属(Alternaria)和芽枝孢霉属(Cladosporium),其他6种属于镰刀菌属(Fusarium),其中1株可产生红色素的镰刀菌的致病能力最强。选择产红色素的致病性最强的镰刀菌,通过测定活体外和活体内的聚甲基半乳糖醛酸酶(PGM)和羧甲基纤维素酶(Cx)2种细胞壁降解酶活性的变化研究该病原菌的致病机理,结果显示,在活体外,PMG的活性随着培养时间延长先增加后降低最后到基本不变,而Cx活性则持续缓慢增加,即在前期主要是PMG起作用,后期则主要是Cx起作用;在活体内,接菌的莲藕的PMG和Cx活性显著高于未接菌的藕(P<0.05),说明PGM和Cx这2种细胞壁降解酶在病原菌的致病过程中起到了重要作用,是重要的致病因子。 The pathogens of lotus root diseases during storage were isolated and identified.The results showed that there were 9 fungi.Artificial inoculation test indicated that the 9 fungi had pathogenicity.According to morphological characteristics,three fungi were identified as Penicillium,Alternaria and Cladosporium respectively,the other six were defined as Fusarium,and one strain of the Fusarium producing haematochrome has the strongest pathogenicity.The Fusarium strain producing haematochrome and having the strongest pathogenicity was evaluated the pathogenic mechanism by determination of PGM and Cx activity,the results showed that in vitro,PMG activity was increased initially and then stepped down,and Cx activity increased in the period,which indicated that PMG mainly took effect at the previous period and Cx played an important role at the later stage.In vivo,PMG and Cx activities of lotus root inoculated pathogenic fungus were higher than the control（p〈0.05）.Cell wall degrading enzyme played a significant role in the period of pathogen causing disease,and which was an important pathogenic factor.

关 键 词： 莲藕 腐烂 病原菌 镰刀菌属 聚甲基半乳糖醛酸酶 羧甲基纤维素酶

领　　域： [农业科学] [农业科学] [农业科学]