云南烟草丛枝症病害研究Ⅲ细胞的超微病变

 超薄切片观察云南烟草丛枝症病害的病叶组织,并抽提试验材料的总核酸电泳检测,结果表明:病组织中检测到与烟草丛枝症病害相关的低分子量RNA,切片中未观察到病毒粒子,薄壁细胞中发现细胞膜系统的畸变:质膜体(plamalemmasome)和双层膜泡囊(double membranous vesicles).质膜体由细胞质膜或液泡膜伸入空泡形成,直径约1000～2000nm,结构类似于类病毒侵染寄主形成的旁壁体.双层膜泡囊是含纤维状物内含物的泡囊,直径约100～200nm,结构类似于某些病毒侵染寄主形成的细胞质泡囊(cytoplasmic vesicles)和植原体(phytoplasmas),但因其广泛分布于寄主细胞中,不能认为是植原体.文献显示这些病变是类病毒和某些病毒侵染的特征,初步认为云南烟草丛枝症病害可能是病毒病害,发病早期细胞内出现小分子核酸侵染的细胞病变特征,此与莫笑晗等发现病株体内含有大量低分子量RNA可能有密切关系.

Studies on Tobacco Witches’Broom Symptom Diseases in Yunnan Ⅲ Ultrastructure Pathology

Leaves of Tobacco witches'broom symptom diseases in Yunnan from diseased plants (detected the Tobacco witches'broom symptom diseases associated-RNA) and healthy plants were fixed and processed for transmission electron microscopy.No virus-like and phytoplasmas were found in diseased thin sections.Aberration of the plasmamenbrane of campanion cells have been identified:the plamalemmasome and cytoplasmic vesicles,The plamalemmasome (with diameter ranged 1 000~2 000 nm) structure likes viroid-associated plamalemmasome,and cytoplasmic vesicles (with diameter ranged 100~200 nm) were double membranous vesicles concluding fibrous thing. The vesicles were different from phytoplasma in distributing.According to some documents,these aberrations were the characteristics of the viroid or virus infected leaf tissue. We think that perhaps the pathogen of the disease is virus.