不同叶色水稻叶绿体密度及基粒结构的计算机图象分析

水稻叶绿体计算机图象分析表明,随着叶片色级的提高,叶绿体表面积密度、体积密度以及两者的比值都相应增加。深色稻叶基粒堆直径与高度、类囊体垛叠数与类囊体厚度、叶绿素与类胡萝卜素含量、气孔导度与净光合率均大于浅色叶片。深色叶片基粒堆密集,有些基粒类囊体出现沿叶绿体长轴方向排列整齐现象;浅色叶片基粒堆稀疏,其中较大的基粒类囊体与长轴呈倾斜排列。

Computer Image Analysis of Density and Grana Ultrastructure of Rice Chloroplast

The density and ultrastructure of grana in rice chloroplast of differently colored leaves due to different nitrogen supply was studied with electron microscope and high resolution computer image analysis system. Standard Rice Leaf Color Scale was used for the grading of leaf color. The results showed that the volume of chloroplast per unit test volume of leaf (Vv), surface area of chloroplasts per unit test volume of leaf (Sv) and Sv/Vv ratio increased with increasing color grade of the leaf (Fig. 3). The mean diameter and thickness of grana, the number of stacks and thickness of thylakoid of darkcolored leaves as well as the chlorophyll content, carotin.old content, stomatal conductance and net photosynthetic rate (Table 2) were greater than these of light-colored leaves. The net photosynthetic rate was highly correlated to the degree of stacking of thylakoid membrane. Some thylakoids in dark-colored leaves were orderly arranged along the long axis of chloroplast, but some big grana in light-colored leaves were arranged slantly so that they could expand into wider space.