铜对苋菜气孔气体交换的影响

Effects of Copper on Gas Exchange of Amaranthus Stomata

[目的]探究铜胁迫对苋菜生理过程的影响。[方法]用土培的方法，研究铜对苋菜幼苗气孔气体交换和光合色素的影响及铜在植物体的分布。[结果]0．5mmol／kg铜处理对苋菜生长有利；随着铜浓度的增加，苋菜净光合速率明显降低，主要归因于非气孔限制；蒸腾速率、光饱和点、袁观量子效率和光合色素含量下降，光补偿点升高；暗呼吸速率在0．5～2．0nmol/kg下升高，在4．0nmol／k（g下降低；苋菜根系铜含量远高于叶片，且随着铜处理浓度的升高，根系和叶片铜含量明显增加。[结论]该研究为苋菜种植和探讨铜对植物毒害的生理机制提供依据。

[ Objective] The purpose of the study was to explore the influence of copper stress on the physiological process of Amaranthus, [ Method] The influences of copper on the stomatal gas exchange and photosynthetic pigments of Amaranthus seedlings and the copper distribution in plants were studied by soil culture. [Result] The treatment with 0.5 nmol/kg copper was favorable for Amaranthus growth. The net photosynthetic rate of Amaranthus reduced obviously along with copper concentration increasing, which was mainly attributed to nonstomatal limitations, Transpiration rate, light saturation point, apparent quantum efficiency and photosynthetic pigments contents decreased, while light corrpensation point increased, Dark respiration rate increased under the copper concentration of 0.5 - 2.0 nmol/kg and decreased under the copper concentration of 4.0 nmol/kg. There was far higher copper concentration in roots of Amaranthus than that in leaves, The copper concentration in roots and leaves obviously increased along with the increment of copper concentration in treatments. [ Conclusion] The research provided the basis for Amaranthus planting and discussing the physiological mechanism of copper poison to plant.