茶树叶绿体的超微结构及其与光合速率的关系

Ultrastructure of tea chloroplast and its relation to photoaynthetic rate.

应用电子显微镜观察了98个茶树品种(品系)叶绿体的超微结构,并对茶树叶绿体超微结构与茶树光合速率的关系进行了初步探讨.结果表明,茶树叶绿体的大小,基粒片层结构,排列等品种间有明显差异;多数茶树叶绿体的基粒片层数为40～60,茶树叶绿体基粒片层数与茶叶光合速率呈显著相关.茶树叶绿体超微结构的研究可为选育高产优质的茶树品种提供参考.

Chloroplast ultrastructure and net photosynthetic rate in 98 tea varieties Camellia sinensis L. Kuntze were studied by electron microscope and ADC-LCA2 infra-red gas analyser respectively. The obtained results showed that shape,size and amount of osmiophilic granules(Os)and stacks of thylakoid membrane(Thm)of the chloroplast greatly varied with the tea varieties studied. Some varieties, such as Maoxie.had shuttle-like chloroplast which possessed bud-like outgrowth at one side in which a great munber of Os were found while the others ,such as Ningzhou No. 5 had big spherical chloroplast in which a lots of Os were found and complex stacks of Thm were centripetally arranged. In some varieties,such as Zhishun, chloroplast had big starch grains by which the stacked Thm were parallely pressed to one side of the chloroplast. Generally .improved tea varieties had more complex stacks of Thm in chloroplast and more Os than local varieties in which big starch grains were usually found. The stacks of Thm in the tea chloroplasts ranged from 13 to 112 lamellae and maximum lamellae was found in tea clone Xicha No. 10 though most of the varieties had 40-60 lamellae of Thm in their chloroplasts. They were found to be below 20 lamellae in 3 varieties and above 90 in 2 varieties. A significantly positive correlation between the lamellae of Thm and net photosynthetic rate was also found in the results and the correlation coefficient is 0. 2394(p<0. 05). It is evident that the complicatedly developed photosynthetic membrane structure is advantigeous to phtosynthesis in tea plant. Therefore, studies on tea chloroplast ultrastructure is a useful way for selecting tea varieties with high yield and quality.