多花黄精不同生长期叶片光合性能比较

Comparison on Leaf Photosynthetic Performance of Polygonatum cyrtonema at Different Growth Stages

【目的】研究多花黄精新、老叶片的光合指标,探明不同生长期叶片光合作用的差异,为多花黄精叶片的分类开发利用提供理论支撑。【方法】以多花黄精为材料,用Li-6800便携式光合仪测定新、老叶片的光合指标,利用差异显著法分析不同生长期叶片对光合作用的影响。【结果】多花黄精老叶比新叶具有更高的叶绿素含量、净光合速率、胞间CO_(2)浓度和CO_(2)总导度,而蒸腾速率和对水汽总导度老叶低于新叶。新叶与老叶之间的叶绿素含量、胞间CO_(2)浓度和净光合速率三者均存在显著差异。【结论】老叶是多花黄精光合作用的主要功能叶,对黄精的光合作用贡献大。生产上应当保存老叶、适当摘除部分新叶加以开发利用。

【Objective】In order to provide the theoretical basis for the classified development and utilization of Polygonatum cyrtonema leaves,the photosynthetic indexes in new and old leaves of P.cyrtonema are studied and the differences in leaf photosynthesis at different growth stages are explored.【Method】The photosynthetic indexes in new and old leaves of P.cyrtonema are determined by using Li-6800 portable photosynthesis system.The effects of leaves at different growth stage on photosynthesis are analyzed by using significant difference method.【Result】The old leaves of P.cyrtonema have higher chlorophyll content,net photosynthetic rate,intercellular CO_(2)concentration and CO_(2)total conductivity compared with those of new leaves,while the transpiration rate and the total conductivity of water vapor of old leaves are lower than those of new leaves.There are significant differences among chlorophyll content,intercellular CO_(2)concentration and net photosynthetic rate between new and old leaves.【Conclusion】The old leaf is the main functional leaf for the photosynthesis of P.cyrtonema,which contributes greatly to the photosynthesis of P.cyrtonema.In production,the old leaves should be preserved and some new leaves could be properly removed for the development and utilization.