黄瓜黑星病菌致病机理的研究Ⅲ 细胞壁降解酶和毒素对寄主超微结构的影响及其协同作用  

PATHOGENIC MECHANISM OF SCAB OF CUCUMBER CAUSED BY Cladosporium cucumerinum Ⅲ EFFECTS AND SYNERGISM OF CELL WALL-DEGRADING ENZYMES AND TOXIN PRODUCED BY C.cucumerinum ON ULTRASTRUCTURE OF CUCUMBER

作　　者：李宝聚[1] 周长力[1] 赵奎华[1] 李凤云[1] 黄国坤[2] 

机构地区：[1]辽宁省农业科学院植物保护研究所,沈阳110161 [2]沈阳农业大学电镜室,沈阳110161

出　　处：《植物病理学报》2001年第1期63-69,共7页Acta Phytopathologica Sinica

基　　金：辽宁省科委重点科技攻关资助项目! (942 0 10 32

摘　　要：本文通过透射电镜和扫描电镜观察 ,初步明确了果胶酶、纤维素酶及毒素对黄瓜叶组织超微结构的影响。在致病过程中 ,3种致病因子起着各自独立又相互联系的作用。3种致病因子对寄主超微结构的影响中 ,纤维素酶分解细胞壁能力最强 ,毒素对细胞质膜的作用最大 ,3种致病因子均可造成质壁分离 ,液泡、内质网受损。而叶绿体的被膜、片层结构主要被纤维素酶降解 ,线粒体的被膜主要被果胶酶降解 ,3种致病因子均能使叶绿体、线粒体内部空泡化。在分解叶表皮的过程中 ,所研究的 3种致病因子首先是果胶酶降解果胶层 ,然后是纤维素酶、果胶酶、毒素对栅栏组织的分解 ,最后是纤维素酶、毒素作用于薄壁细胞壁 ,毒素、纤维素酶、果胶酶协同作用于细胞内部组织。The effects of the cellulase, pectinase and toxin produced by Cladosporium cucumeri num on the leaf cell of cucumber were studied by TEM and SEM. The results indicated that the three pathogenic factors played independent and symplastic roles. The cellulase and pectinase played leading roles respectively in decomposition of cell wall and plasma membrane. The three factors could all result in plasmolysis and damage vacuoles and endoplasmic reticulum. Chloroplast envelope and lamellae structure were mainly digested by cellulase, whiles, mitochondrion envelope was chiefly digested by the pectinase. Each of the three factors could cause vacuolation in chloroplast and mitochondria. During the process of breach up the structure of epidermis of leaf, the cellulase acted on reticulate region, then the pectinase dissolved pectic layer. Following this, palisade tissue was damaged by the cellulase, pectinase and toxin.Finally, parenchyma was destroyed by cellulase and toxin,successively.

关 键 词：黄瓜 黑星病菌 超微结构 致病机理 细胞壁 果胶酶 纤维素酶 毒素 协同作用 

分 类 号：S436.421.1[农业科学—农业昆虫与害虫防治] S432.42[农业科学—植物保护]