Effects of high salinity on physiological and anatomical indices in the early stages of Populus euphratica growth

Abstract

The effects of salinity stress on stomatal aperture and density, xylem vessels, the activities of antioxidant enzymes, such as superoxide dismutase (SOD) and peroxidase (POD), and xylem embolism (PLC values) in Populus euphratica in the arid ecosystem of China. Pot experiment was conducted at different concentrations of salt (50, 100, 150, and 200 mM NaCl) contained in the irrigation water used for 3 months The POD activity increased with the increase in the severity of NaCl stress, but SOD activity was varied at different levels of salt. Results indicated that salt treatment reduced stomatal aperture and leaf photosynthetic capacity. However, the significant reduction in the stomatal area, in the length of stomata openings and an increase in stomata density were noticed. Salinity stress affected water transport, which reduced native PLC value, whereas xylem vessel area was also decreased. Presented results open the possibility of genetic improvement for selecting the high salt-tolerant of Populus spp.to reclaim salinized lands.