宿根矮化病菌对甘蔗茎细胞超微结构的影响

Effects of Ratoon Stunting Disease on Ultrastructural in Sugarcane Stem Cells

甘蔗宿根矮化病(Ratoon stunting disease,RSD)病原细菌一般集中在甘蔗基部2～3节间处.利用透射电镜对感染RSD的甘蔗茎组织细胞进行超微结构观察,结果显示细胞内和细胞壁都发生了明显的病理变化.甘蔗茎细胞被RSD病原细菌侵染后,细胞内积累有大量分布不均的电子致密物质,这种物质可能与甘蔗茎细胞抵抗、减少或延迟RSD病原菌入侵的抗性机制相关.这些电子致密物质在感病细胞内均有出现,而正常细胞内没有.维管束导管细胞壁增厚,表面附着一层胶黏物质;有的细胞壁厚薄不均,局部变形断裂,成为细胞壁碎屑和纤维丝.

The bacterium associated with ratoon stunting disease of sugarcane usually gather in the 2-3 internodes of base stem section of sugarcane.The ultrastructures of the stem tissue infected by ratoon stunting disease were observed with electron microscopy.The results suggested that cytopathological alteration apparently occurred inside cells and on the cell wall.A large amount of electron-dense substances accumulated in the infected cells,which was presumed to be associated resisting,reducing or delaying the invasion of this disease.The electron-densed substances were only found in the infected cells.The cell wall was thickened and there was a layer of adhesive materials in the vessels of vascular bundle.Some cell walls were uneven with different thickness,and parts of them were broken into crumbs and fiber silks.