潢川金桂夏季光合特性分析

PHOTOSYNTHETIC CHARACTERISTICS OF OSMANTHUS FRAGRANS′ HUANGCHUAN JINGUI′IN SUMMER PRELIMINARY RESEARCH

采用Li-6400XT便携式光合作用测定仪对潢川金桂成年树光合特性进行研究。结果表明:夏季潢川金桂净光合速率日变化呈明显的双峰型,最高峰出现在9:00,其净光合速率为10.05μmol/(m^2·s),次高峰出现13:00,其净光合速率为8.980μmol/(m^2·s),有明显的光合午休现象。根据光响应曲线可以得出潢川金桂的光饱和点(LSP)为1290μmol/(m^2·s),光补偿点(LCP)为74.21μmol/(m^2·s),表观光量子效率为0.0267,由CO2响应曲线可以得出CO2饱和点(CSP)为530μmol/mol,CO2补偿点为61.24μmol/mol,羧化效率为0.0433。潢川金桂具有较高的CO 2补偿点和光饱和点说明潢川金桂是喜光的阳性植物。

The photosynthetic characteristics of leaves in Osmanthus fragrans‘Huangchuan Jingui’were studied with Li-6400XT portable photosynthesis system.The results show that the diurnal variations of photosynthetic rate showed a curve with two peaks and a apparent phenomenon of midday depression in photosynthesis and the maximum peak of photosynthetic rate(10.05μmol/(m^2·s))appeared at 9:00 AM and inferior peak(8.980μmol/(m^2·s))occurred at 13:00.According to the light response curve,a conclusion can be drawn that the light saturation point(LSP)and the light compensation point(LCP)for the leaves of Osmanthus fragrans‘Huangchuan Jingui’were 1290μmol/(m^2·s)and 74.21μmol/(m^2·s),with apparent quantum yield(AQY)being 0.0267.The CO2 saturation point(CSP)and the CO2 compensation point(CCP)were 530μmol/mol and 61.24μmol/mol,and the carboxylation rate(CE)was 0.0433 based on the carbon dioxide response curve.Higher the CO2 compensation point and the light saturation point illustrate Osmanthus fragrans‘Huangchuan Jingui’with the character of very bright light sun plants.