雷竹光合特性的研究

Study on the Photosynthetic Characteristics of Lei Bamboo Leaves

对雷竹叶片光合速率及其主要影响因子的周年变化进行了研究 ,结果表明 :在晴到少云的天气条件下 ,雷竹光合速率日变化呈双峰曲线 .光强、温度、水分等外界环境因子对雷竹光合作用有显著影响 .强光、高温、低湿引起雷竹叶片光合“午睡” .雷竹光合速率年变化也呈双峰曲线型 .环境因子及 Rubisco,Rubisco活化酶 ,蛋白质 ,叶绿素等对光合速率都有显著影响 .雷竹幼叶的光合速率 ,光饱和点及相关影响因子较二龄叶高 ,具有较高的光合生理特性 .雷竹叶片的光饱和点约为 1 688～ 1 834μmol CO2 · m-2 · s-1;光补偿点约为 1 60～ 2 2 2μmol CO2 · m-2 · s-1.

Experiments were conducted to study diurnal changes and seasonal fluctuation of net photosynthetic rate and its major factors of Lei bamboo leaves Net photosynthetic rate of Lei bamboo reaches peaks at 10∶00 and 14∶00 respectively in dry heat conditions And it reaches also peaks on June and October of one year respectively The reason of 'sleeping' at noon is Photosynthetic photon flux (PPF) and temperature (T) increasing and relative humidity(RH) decreasing The diurnal changes and seasonal fluctuation of net photosythetic rate were affected by its major factors,ie PPF,T,intercellular CO 2 concentration(Ci),stomatal conductance(SC),transpiration(TR),and RH,Rubisco and Rubiscoactivase,protein,chlorophyll contents as well The net photosynthetic rate and the light saturating photosynthetic rate (LCP) of one year old leaf was higher than those of two year old leaf The LSP measured in leaves was in a range of 1 688～ 1 834 μmolCO 2· m 2 · s 1 The LCP was 160～222 μmolCO 2·m 2 ·s 1