Influence of salt stress on ecophysiological parameters of Periploca sepium bunge
J.K. Sun, T. Li, J.B. Xia, J.Y. Tian, Z.H. Lu, R.T. Wanghttps://doi.org/10.17221/227/2010-PSECitation:Sun J.K., Li T., Xia J.B., Tian J.Y., Lu Z.H., Wang R.T. (2011): Influence of salt stress on ecophysiological parameters of Periploca sepium bunge. Plant Soil Environ., 57: 139-144.
An experiment was carried out to investigate the effect of salt stress on Periploca sepium Bunge seedlings using three levels of salinity, 50 mmol/L, 100 mmol/L, and 200 mmol/L sodium chloride (NaCl) solution. The results showed that growth parameters and net photosynthetic rate (Pn), stomatal conductance (Gs) of Periploca sepium Bunge were enhanced under low salinity levels (50 mmol/L NaCl), which reduced strongly with increasing salinity levels. Under 100 mmol/L NaCl and 200 mmol/L NaCl stress, the decline of Pn was mainly caused by non-stomatal factors. The water use efficiency (WUE), apparent light use efficiency (LUE), carboxylation efficiency (CUE) were enhanced under low salinity levels (50 mmol/L NaCl), the maximum value of WUE was observed at 100 mmol/L NaCl, the minimum value of WUE was observed at 200 mmol/L NaCl, the LUE, CUE were reduced by 52% and 47%, at 200 mmol/L NaCl, respectively, compared to control. Activities of the antioxidative enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were enhanced by low salinity treatment (50 mmol/L NaCl), but CAT activity decreased at 200 mmol/L NaCl stress. Malondialdehyde (MDA) was non-significant compared to the control under low salinity levels (50 mmol/L NaCl), the maximum value was observed at 200 mmol/L NaCl. These results suggest a possibility to improve saline soil utilization of Periploca sepium Bunge in Yellow River Delta region.Keywords:
salinity; growth; gas exchange; protective enzyme; lipid peroxidation