【摘要】 为了探索‘红霞杨’的光合能力,利用Li-6400便携式光合测定仪,测定了‘红霞杨’的光合指标,绘制了光响应曲线图和光合指标日变化图,对光响应曲线用直角双曲线修正模型进行拟合和计算,并与‘四季杨’和‘全红杨’对比。结果表明:从曲线分布位置、光补偿点(LCP)、光饱和点(LSP)、表观量子效率(AQY)、最大净光合速率(Pnmax)以及同光强下的净光合速率(Pn)比较来看‘,红霞杨’的光合能力比较差,没有与其相近的同类树木‘全红杨’和‘四季杨’强‘;红霞杨’的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和胞间CO2浓度(Ci)等光合指标日变化曲线图也比较平稳,没有明显的峰值,对光的应激反应比较弱,自身调节能力差。更多还原

【Abstract】 The paper aims to explore the photosynthetic capacity of Populus euramericana cv.’Hongxia’. The author measured the photosynthetic indexes of Populus euramericana cv.’Hongxia’by Li-6400 portable photosynthetic meter, plotted the light response curve and the diurnal variation map of photosynthetic index,and fitted and calculated the light response curve by modified rectangular hyperbola, compared with the Populus spp and Populus euramericana cv.’Quanhong’. The results showed that: from the perspectives of the line distribution position, the light compensation point(LCP), light saturation point(LSP), apparent quantum yield(AQY), maximum net photosynthetic rate(Pnmax) and net photosynthesis rates(Pn) under the same light intensity, the photosynthetic capacity of Populus euramericana cv.’Hongxia’was poor, and it was not as good as that of the similar trees Populus spp and Populus euramericana cv.’Quanhong’; the diurnal variation curves of the net photosynthetic rate(Pn), transpiration rate(Tr), stomatal conductivity(Gs) and stomatal CO2 concentration(Ci) were relatively stable with no obvious peak value, and the response to light stress was weak and the self-regulation ability was poor.更多还原