鹅毛竹花后叶片衰老生理特性

以鹅毛竹为材料，以未开花竹为对照，分析了鹅毛竹花后叶片生理变化特性。结果表明：鹅毛竹开花后总体上叶片叶绿素、可溶性蛋白质和糖含量不断下降，并始终低于未开花竹相应指标，而可溶性糖与蛋白质含量比值、MDA含量呈不断增加趋势，并始终高于未开花竹相应指标。随着试验时间的延长，上述各指标的变幅以及与未开花竹的差距增大，表明花后叶片衰老逐渐加快。开花初期开花竹叶片SOD活性明显高于未开花竹，而POD、CAT活性明显低于未开花竹，后期开花竹各保护酶活性的变幅明显大于未开花竹，表明鹅毛竹开花后保护酶系统间的平衡失调。推测活性氧的大量产生以及保护酶系统间平衡失调导致的膜脂过氧化程度增加，膜以及蛋白质等生物大分子结构与功能的破坏及其降解等可能是开花竹花后叶片衰老加快的主要原因之一。

Physiological characteristics of leaf senescence in Shibataea chinensis after anthesis

In order to explore the physiological change of leaf senescence of bamboos after anthesis, Shibataea chinensis was taken as experimental material. The results showed that the contents of chlorophyll, soluble protein and soluble sugar of bamboos after anthesis decreased gradually, which were always lower than those of the control group during the experiment. But the changes in ratio of soluble sugar content to soluble protein, and MDA content increased gradually, which were higher than those of control group throughout the experiment. With the prolongation of testing time, the variation range of indexes and the gap compared to the control indicated that leaf senescence of bamboos accelerated gradually after anthesis. At the early flowering stage, the SOD activity of flowering bamboo was significantly higher than those in the control group, but the POD and CAT activities were significantly lower. At the late stage, the change degrees of protective enzyme activities were significantly higher than those of control group, which showed the imbalance of protective enzyme system. We guess that production of a great quantity of active oxygen and imbalance of protective enzyme system led to the destruction and degradation of the structures and functions of biomembrane and biomacromolecule and the aggravation of the lipid peroxidation, which may be one of the main cause that accelerates the leaf senescence of bamboos after anthesis.