'金光杏梅'叶片净光合速率与生理生态因子的关系

以‘金光杏梅’成熟叶片为试验材料,采用CI-301型便携式CO2气体分析仪测定了其叶片净光合速率(Pn)日变化,并通过多元逐步回归和通径分析方法探讨了净光合速率与生理生态因子间的关系。结果表明:‘金光杏梅’叶片净光合速率日变化为双峰曲线,在上午10:00和下午15:00分别出现一次高峰,具有典型的"午休"现象,它是由气孔因素和非气孔因素两种因素造成的;叶片气孔导度和蒸腾速率日变化均与净光合速率日变化呈正相关,回归方程分别为yPn=0.947xGs2 0.2874xGs 57.945,(R2=0.8534)和yPn=0.8079xTr0.5421,(R2=0.5716);影响‘金光杏梅’叶片净光合速率的主要生态因子是光合有效辐射和大气CO2浓度,主要生理因子是气孔导度和蒸腾速率。

Relationship between Net Photosynthetic Rate and Its Physo-ecological Factors in 'Jinguang'Plum

The diurnal changes of net photosynthesis rate(Pn) in leaves of 'Jinguang' plum were studied by CI-301 CO2 analyzer,and the relationship between the Pn and its physo-ecological factors were studied by path analysis and stepwise regression equation.The results showed that the curve of diurnal variation of Pn was demonstrated two peaks in clear day,which appeared at 10:00 and 15:00 respectively.There was a clear depression at noon,which caused by stomatal conductance and nostomatal factors.Correlation analysis showed there were positive relationship between Gs and Tr and Pn,and the correlation equations were respectively yPn=0.947xGs2 0.287 4xGs 57.945,(R2=0.853 4)and yPn=0.807 9xTr0.542 1,(R2=0.571 6).It was PAR and Ca that affected the changes of Pn among the ecological factors,and Gs and Tr played very important roles in the changes of Pn among the physiological factors.