光呼吸条件下栾树和辣椒光合电子流的分配研究

用Li-6400光合仪同时测定了栾树和辣椒在温度为30℃、CO2浓度为380μmol·mol-1下的气体交换和叶绿素荧光数据。结果表明,栾树在饱和光合有效辐射时光合电子用于碳同化、光呼吸和其他途径的量分别为72.68、45.68和29.40μmol·m-2.s-1;辣椒在光合有效辐射为2000μmol·m-2.s-1时光合电子用于碳同化、光呼吸和其他途径的量分别为142.24、40.24和131.52μmol·m-2.s-1。揭示了在光呼吸条件下用Valentini和Epron等方法高估了辣椒和栾树的光合电子用于光呼吸的量,同时也高估了光呼吸在辣椒和栾树中的保护作用。

Investigation on Allocation of Photosynthetic Electron Fluxes for Goldenrain Tree(Koelreuteria paniculata Laxm.) and Capsicum(Capsicum annuum L.) under Photorespiratory Conditions

In order to evaluate the photosynthetic electron transport and allocation for goldenrain tree（Koelreuteria paniculata） and capsicum（Capsicum annuum）,gas exchange and chlorophyll fluorescence for them at CO2 concentration of 380 μmol·mol-1 and 30 ℃ under photorespiratory condition,using a gas analyzer Li-6400,were measured.The results showed that the photosynthetic electron flows to fix CO2,photorespiration and others associated with electron-consuming processes were 72.68,45.68 and 29.40 μmol·m-2·s-1 for goldenrain tree at saturation irradiance,respectively;the photosynthetic electron flows to fix CO2,photorespiration and others associated with electron-consuming processes were 142.24,40.24 and 131.52 μmol·m-2·s-1 for capsicum at irradiance of 2 000 μmol·m-2·s-1,respectively.The calculated results suggest that the electron flows both in fixation of CO2 and photorespiration are overestimated by method of Valentini and Epron under photorespiratory conditions.At the same time,the role of photorespiration in protecting photosynthetic organism for goldenrain tree and capsicum is overestimated under photorespiratory conditions.