花生叶片衰老过程中光合性能及细胞微结构变化

The Changes of Photosynthetic Properties and Cell Microstructure in Peanut Leaves During Leaf Senescence

在大田条件下 ,选用鲁花 11号和辐 870 7两个高产花生品种 ,研究了花生叶片衰老过程中光合性能及细胞微结构变化。结果表明 ,花生叶片展开至衰老过程中 ,叶绿素含量、净光合速率 (Pn)变化趋势可用函数式Y =A +Bx+Cx2 (Y为上述各指标 ,x为叶片展开后天数 )较好描述。花生叶片衰老期间叶绿体结构发生明显变化 :外形由长椭圆形逐渐趋于圆形 ;叶绿体内淀粉粒由多而大逐渐变少而小 ,而油脂则由小而少变大而多 ;基粒片层由细长沿叶绿体长轴方向排列 ,逐渐变粗短、排列杂乱至模糊不清 ,最后叶绿体被膜破裂 。

The changes of photosynthetic properties and cell microstructure in peanut leaves during leaf senescence were studied with two high yielding peanut cultivars (cv. Luhua 11 and Fu 8707) . The main results showed that during the whole process of leaf growth and senescence, changes of photosynthesis rate (Pn) and contents of chlorophyll in leaves, could be described with a parabolic function, Y=A+Bx+Cx 2, (where Y refers to the values of above parameters and X to the days after leaf unfolding). During peanut leaf senescence,the shape of chloroplast changed gradually from long ellipes to circles. The starch globule in chloroplast altered gradually from more and larger size to fewer and smaller, but the oil globule from fewer and smaller to more and larger.The grana lamellae varied progressively: from thinness and length to thickness and shortness; form ranking along the long axle direcfion of choroplast to arranging disorderly and blurring finally. At last, the membrane envelope of chloroplast broke so the inclusion seeped out to the cell, the chloroplast broke up.