不同CMV分离物侵染寄主的超微结构变化

Ultrastructural Alteration of Host Plants Infected with Different Cucumber Mosaic Virus Isolates

应用电镜观察了黄瓜花叶病毒CMV不同分离物侵染寄主的细胞超微结构变化。来自一串红 (Salviasplendens)的不含卫星RNA分离物M 2 2侵染心叶烟 ,病毒粒子散布于细胞质 ,在液泡中形成大片病毒粒子结晶 ,液泡膜边缘产生小泡结构 ,完整的病毒粒子穿过胞间连丝在细胞间运转 ,胞间连丝中央部分有扩张现象。自然感染三生烟的含坏死卫星RNA分离物 8 S1侵染普通烟 ,病毒粒子分散于细胞质 ,在液泡中未观察到结晶体 ,叶绿体产生囊泡结构 ,部分病毒粒子处在叶绿体空泡中。田间寄主上受 8 S1侵染的三生烟细胞质中分布着大量球形病毒粒子 ,叶绿体也产生含有病毒粒子的囊泡结构。表明含有卫星RNA和不含卫星RNA的CMV分离物引起的细胞病变特征存在差别 ,可能是CMV卫星RNA参与病理变化的依据之一。

The ultrastructural alterations caused by the infection of two cucumber mosaic virus isolates were investigated. Spherical virus particles of CMV M 22, an isolate originally from Salvia splendens , scattered throughout the cytoplasm and aggregated into crystals in the vacuoles of tobacco cells. The existence of virus particles inside the chloroplast was not detected for this isolate. But virus particles were found being aggregated through the plasmodesma, that indicated the way of cell to cell movement of this isolate. Virus particles of CMV 8 S1, an isolate with necrosis satellite RNA and originally from naturally infected tobacco, scattered throughout the cytoplasm and in the vacuoles of abnormal chloroplasts. In the tobacco leaf cells natural infected by CMV 8 in the field, numerous spherical particles and abnormal chloroplasts were observed. The results suggest that ultrastructural alterations induced by different CMV isolates are quite variable. This is a direct evidence of satellite RNA involvement in pathogenic process by CMV.