An international team led by researchers from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences found that long-term exposure to salinity, drought and combined stresses would exert negative effects on halophyte Halogeton glomeratus.

The findings were published in Physiologia Plantarum on Oct. 9.

Soil salinity and drought are regarded as the most critical and adverse environmental factors for plants. Recent reports have suggested that the cultivation of halophytes can efficiently reduce soil salinity, which is an effective way to reclaim saline soils in arid and semi-arid lands.

Therefore, understanding the mechanisms adopted by halophytes in the adaptation to drought and salt stresses is important in phytoremediation of saline soils in arid and semi-arid lands.

In this study, the researchers tested the morphophysiological responses of the halophyte Halogeton glomeratus grown under control, single or combinations of 60 days' drought and salt treatments.

They found that drought, salinity and combination of these two stressors inhibited plant growth, leaf photosynthetic pigments content, gas exchange parameters and water potential. The inhibition was more prominent under combined drought and salinity treatment compared with these two stressors individually performed.

The study also showed that combined drought and salinity treatment induced more severe oxidative stress. Nevertheless, H. glomeratus was equipped with specific mechanisms to protect itself against drought and salt stresses, including up-regulation of superoxide dismutases and catalase activities and accumulation of osmoprotectants.