Transmission Electron Microscopic Study of Subcellular tructureof Yellow Tea Cultivar ‘Zhonghuang 2’

Abstract:

The subcellular structures of the second and sixth leaves of yellow tea cultivar "Zhonghuang 2" and normal green tea cultivar "Longjing 43" were studied by transmission electron microscope. It was found there were no significant differences in ultrastructure and distribution of nucleus，cytosol，mitochondrion and golgi apparatus. The largest difference was existed in chloroplast ultrastructure. Compared to Longjing 43，smaller chloroplasts and less grana lamellae were found in Zhonghuang 2. The chloroplast lamellae numbers were increased in the sixth leaves of Zhonghuang 2，but were still less than those in Longjing 43. The chloroplast lamellae numbers were consistent with the chlorophyll contents determined. Furthermore，the second leaves of Zhonghuang 2 turned green and the chloroplast lamellae numbers increased under shading treatment. In summary，it was the first finding that the yellow tea cultivar "Zhonghuang 2" was correlated with the biosynthesis of chloroplast lamellae，which will also be a basis for further understanding its yellowing mechanism in Zhonghuang 2.