Effect of Mn Tozicity on Ecophsiological Responses in Two Populus cathayana Populations
The cuttings of Populus cathayana was exposed to Hoaglands solution containing four different manganese (Mn) concentrations (0, 0.1, 0.5 and 1 mM) in a greenhouse to characterize the physiological and biochemical basis of Mn resistance in woody plants. Two contrasting populations of P. cathayana were used in our study, which were from the wet and dry climate regions in western China, respectively. The results showed that high concentration of Mn caused significant decrease in shoot height and biomass accumulation. Moreover, Mn treatments caused the accumulation of hydrogen peroxide (H2O2), and then resulted in oxidative stress indicated by the oxidation of proteins. Many ecophysiological responses were employed to cope with the toxicity of Mn including the increase in the contents of non-protein thiol (NP-SH), reduced glutathione (GSH), phytochelatins (PCs) for the chelation of Mn and for the antioxidant of reactive oxygen species. On the other hand, there were different responses to Mn stress between the two contrasting populations. Compared with the dry climate population, the wet climate population not only accumulated more Mn in plant tissues especially in leaves, but also exhibited lower activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX), thus caused more serious oxidative damage. Therefore, our results showed that the wet climate population was more susceptible to Mn stress than the dry climate population.
Poplar Manganese treatment Ozidative stress
Ke Chen Yanbao Lei
Department of Bioscience and Biotechnology Southwest University of Science and Technology Mianyang, Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Mengla, Yunnan 666303, Chia
国际会议
上海
英文
4377-4381
2008-05-16（万方平台首次上网日期，不代表论文的发表时间）