光叶子花不同叶位叶片叶绿素含量和光合作用研究

Studies of Chlorophyll Content and Photosynthesis of Blades in Different Leaf Positions of Bougainvillea Glabra Choisy

本文以光叶子花炼苗60 d组培苗为材料,对光叶子花不同叶位叶绿素含量、呼吸作用(Re)、气孔导度(Gs)、胞间CO2浓度(Ci)、净光合速(Pn)、蒸腾速率(Tr)、叶面饱和水汽压亏缺(Vpdl)等进行了测定。试验结果表明,光叶子花叶片单位重量和单位面积叶绿素含量、净光合速度和水分利用效率(WUE)均随叶位上升呈先增大后减小趋势变化,其最大值都出现在第6叶位叶片;叶片呼吸速率、气孔导度和蒸腾速率均随叶位上升而减小;叶片胞间CO2浓度随叶位上升呈先减小后增大变化;叶面饱和水汽压亏缺随叶位上升而增大。由于光叶子花中部叶片叶绿素含量、Pn和WUE相对较高,因此在今后的栽培管理中应对中部叶片加强保护。

The determination was made on the chlorophyll content, respiration rate （Re）, stomatal conductance （ Gs ）, intercellular C02 concentration （ Ci ）, net photosynthesis rate （ Pn ）, transpiration rate（Tr）, leaf surface vaoor deficit（ Vpdl） of blades in different leaf positions of Bougainvillea glabra Choisy tissue-cultured seedlings which were transplanted in the flowerpots for 60 days from tube. The results showed that with the leaf position elevating, the chlorophyll content of average weight and area, net photosynthesis rate and water use efficiency first increased, then they gradually decreased, whose maximum value emerged at the sixth leaf. The respiration rate, stomatal conductance and transpiration rate decreased with the increase of the leaf position. With the leaf position elevating, the intercellular CO2 concentration first decreased, then increased and got to the minimum value. The vapor deficit at the leaf surface increased with the elevation of the leaf position. The chlorophyll content, net photosynthesis rate and water use efficiency of middle leaves of Bougainvilles glabra Choisy plants were relatively higher than those of other parts, so the middle leaves should be protected in the future cultivation and management.