黑暗对西瓜幼苗叶片叶绿体超微结构的影响

本文利用透射电镜（TEM），对黑暗常温条件下西瓜幼苗叶片的叶绿体超微结构进行了观察。结果表明：随着黑暗时间的延长，叶绿体的超微结构受损越严重，黑暗2天，叶绿体膨胀，基质片层减少且排列不规则，淀粉粒消失；黑暗4天，片层扭曲甚至解体；黑暗6天，片层结构完全消失，叶绿体变成球形，膜破损严重，叶绿体趋于解体。恢复光照（300μmol·m^-2·s^-1）2天，淀粉粒开始积累，证明叶绿体进行光合作用的功能开始恢复，但基粒较少，且模糊；恢复6天时，基粒垛叠较丰富，且片层清晰；黑暗时间越短，恢复越快。

Effects of darkness on ultrastructure in chloroplast of watermelon seedling leaves

The ultrastructural changes in chloroplast of watermelon seedling leaves under darkness were observed by transmission electron microscopy(TEM).TEM observations indicated that ultrastructural damages in chloroplast became severe when it is kept under darkness.After 2-day treatment with darkness,the chloroplast expanded,the stroma lamellae decreased and arranged unregularly,the starch particles disappeared.After 4-day treatment with darkness,the lamellae were distorted or even disintegrated.After 6-day treatm...