Effects of simulated acid rain on photosynthesis of leaves and organic acid secreted by roots of Cycas debaoensis Y.C.Zhong et C.J.Chen
[Objective]Effects of acid rain on photosynthesis changes of leaves and organic acid secreted by roots of Cycas debaoensis were studied to better protect Cycas debaoensis. [Method]According to the rainfall characteristics in Guangxi, simulated acid rain spraying was adopted to investigate changes in organic acirl secreted by roots and photosyn-thetic physiology. [Result]Under pH 2.1 acid rain stress, soil pH decreased, the plant leaves showed necrotic lesion, and net photosynthetic rate, stomalal conductance, transpiration rate and the plant intercellular C02 concentration in leaves were all seriously impacted. Oxalic acid was the main organic acid detected from the roots of Cycas debaoensis. The oxalic acid secreted by the roots of Cycas debaoensis showed no change under moderate acid rain stress (pH 4.2 and pH 3.1), but obviously increased under strong acid rain stress(pH 2.1). [Conclusion ]Simulaled acid rain with pH 2.1 severely damaged the leaves of Cycas debaoensis, and weakened their photosynthesis. In response, Cycas debaoensis roots had to secrete more organic acid to adapt and resist overwhelming acid rain stress.
国家科技期刊平台
NSTL
万方数据
维普
