甜菜花叶病毒病研究之二——感病细胞超微结构观察

对不同时期感染甜菜花叶病毒(BtMV)的叶片,进行病理变化系列观察。早期侵染(7天前)的细胞质、细胞器均无变化,随着症状发展,风轮状内含体、束状内含体、细胞核卫星体,细胞质泡囊化旁类似病毒的束状结构,20天达到了高峰,风轮状及束状内含体一直持续两个月还存在。田间样品也观察到了典型的风轮状及束状内含体。细胞核卫星体出现很少。侵染后期,细胞质减少,叶绿体比相应健株提前出现淀粉粒,噬锇颗粒等,基粒片层也提前消解,表现细胞提前衰老的特征。此外细胞内还有许多健株没有的泡状结构。一种为旁壁体,可能与细胞壁加厚有关;一种为多重泡体的叠加,可能是液泡的吞噬作用加强与外源物质(BtMV)侵入有关;另外还有一种可能是过氧化物酶体或线粒体在病毒诱导下泡囊化,其作用不清楚。

ON THE OBSERVATION OF ULTRASTRUCTURE OF BEET LEAF CELLS INFECTED BY BEET MOSAIC VIRUS

The leaf tissue both healthy and infected were sampled from sugar beet plant at intervals of 7,15,20,30 and 60 days after inoculation. Ultrathin sections were prepared from above samples. The results of electron microscopic observation showed that in the early days (before 7 days) ,all cells,either from infected or noninfected plant were healthy. Samples from the time of developing symptoms,pinwheels,bundle inclusions,nucleorous satellite bodies, paracrystallins proteinaceous inclusions appeared in the infected cells. The degree of alteration increased with age up to 20 days after inoculation. These include chloro-plasts,mitochondria,vacuoles and others.The present papers demonstrated the noticeable damages of the cell ultrastructure caused by the virus infection.