【摘要】 采用指数函数模型对16个1年生楸叶泡桐无性系嫁接苗的光响应曲线进行拟合,分析其光合生理特性。结果表明,不同无性系间初始量子效率（α）、最大光合速率(P_max)、暗呼吸速率（R_d）、最大浄光合速率(P_nmax)、光补偿点（I_c）、光饱和点(I_sat)和可利用光幅度（PR）呈显著或者极显著水平的差异（F=6.632⁹.880）,7个光响应曲线方程特征参数的变异系数为17.263 1%³6.551 5%,说明不同无性系间光响应曲线各特征参数差异较大,可以利用的改良潜力较大。依据方差分析结果初选出CSD08、CHN01、CSD06和CHB02等4个光合特性优良的无性系。通过聚类分析将16个参试无性系分为4大类,不同类之间无性系各光响应曲线方程特征参数均呈显著或者极显著水平的差异（F=5.220¹7.708）,其中第I类无性系（CSD08、CHN01、CSD06）为具有α、P_max、P_nmax、I_sat、PR最高或相对较高,R_d、I_c相对较低等特性,可以作为复选出的苗期光合生理特性优良的楸叶泡桐无性系。更多还原

【Abstract】 In order to analyze the photosynthetic physiological characteristics of 16 clones of Paulownia catalpifolia with 1-year-old engrafted seedlings,photosynthetic light-response curves of these clones were fitted through exponential function model.Significant or extremely significant differences were found among different clones（F=6.632⁹.880）in the parameters such as the initial quantum efficiency（α）,maximum net photosynthetic rate(P_max),dark respiration rate（R_d）,maximum net photosynthetic rate(P_nmax),light compensation point（I_c）,light saturation point(I_sat)and the available optical amplitude（PR）.The coefficients of variation of these 7 parameters were 17.263 1³6.551 5,and indicated relatively large potential genetic improvement.Clone CSD08,CHN01,CSD06 and CHB02 were selected as excellent photosynthetic clones preliminarily through the analysis of variance.The 16 clones were divided into 4 classes by cluster analysis.The light-response curve parameter of different classes showed significant or extremely significant differences（F=5.220¹7.708）.Parameters of α,P_max,P_nmax,I_sat and PR of class I including CSD08,CHN01 and CSD06 were the highest or relatively higher.R_d and I_c were relatively lower.It was concluded that CSD08,CHN01 and CSD06 could be selected as the relatively better clones with superi-or photosynthetic physiological characteristics at seedling stage.更多还原