茌梨叶片光合作用“午睡”现象的研究

STUDY ON "MIDDAY REST" OF PHOTOSYATHESISIN CHI LI LEAVES

茌梨叶片光合速率的日变化存在着“午睡”现象。叶片含糖量和比叶重日变化,CO_2补偿点和光下呼吸速率日变化均不同程度地与“午睡”现象有关。光照和温度影响CO_2补偿点、光下呼吸速率。空气相对湿度左右气孔开度,制约光合速率高低。人工供水可调控空气湿度,形成有利于茌梨叶片光合作用的综合环境因子,而光合速率高,“午睡”现象弱。

The phenomemon of “Midday Rest”in daily variation of photosynthetic rate of Chi Li leaves was studied.The daily variation of leaf sugar contents,SLDWS,CO_2 compen- sation points and respiratory rates in light are related to the phenomenon of “Midday Rest ”,light intensity and temperature affect the respiratory rate and CO_2 compensition point while relative humidity of air masters the opening degree of storrna and the photo synthet- ic rate.Watering can control the relative humidity and form a suitable enviremental condi- tion which enables a higher photo synthetic rate and reduces the “Midday Rest” in leaves.