毛竹叶片发育过程中光合生理特性的变化特征

Photosynthetic characteristics in the development process of Phyllostachys edulis

运用植物气体交换测定和叶绿素荧光测定等分析技术,测定分析毛竹Phyllostachys edulis叶片发育过程中的色素质量分数、光响应进程和叶绿素荧光参数的变化特征。结果表明:(1)毛竹叶片从幼叶生长到叶片成熟的各发育阶段,叶绿素质量分数和净光合速率不断增加而趋于稳定,叶片对光能的捕获和利用能力也随之增强。(2)叶片从伸出到成熟,叶片的最大光化学效率(φ_(Po))的变化不明显。(3)毛竹叶片经放叶、展叶至第15天,PSⅡ反应中心数不断增加,其数量约升高54.4%。(4)PSⅡ电子受体蛋白QA被还原的速率和还原需要的能量不断减少,用于推动QA下游电子传递的能量不断增加。因此,毛竹叶片光合功能从幼叶形成至第15天完全展叶,叶片发育趋于完善,表明毛竹叶片具备正常的光合生理功能,可以充分利用毛竹群落生境的光能资源。

Using gas exchange and chlorophyll fluorescence technologies, changes in the net photosynthetic rate, pigment content, and chlorophyll fluorescence parameters of bamboo （Phyllostachys edulis） leaves were tested. Results showed that 1） as young bamboo leaves grew to maturity, in different developmental stages, the chloro-phyll content and net photosynthetic rate increased, as did the light energy capture and utilization ability. 2） From leaf out to maturity, the maximum photochemical efficiency of leaves （φPo ） did not change. 3） Also, for bamboo leaves, from leaf out to 15 d, the PS Ⅱ reaction center number increased about 54.4%. 4） The rate at which the PS Ⅱ receptor side primary quinone electron acceptor （： a） decreased and the energy required for reduction continuously decreased with the energy used to drive the ： A downstream electron transfer increasing. Therefore, bamboo leaf photosynthetic functions from the time the young leaves formed to after 15 d of fully ex-panded leaves tended to be optimal, and leaves of Ph. edulis with normal photosynthetic physiological functions could make full use of the habitat community’ s solar energy resources.