Regulations of drought and salt tolerance in Salsola L., species in the arid deserts of United Arab Emirates

Abstract

Drought and salt stresses are among the important factors limiting plant growth and distribution in the United Arab Emirates (UAE) deserts. The current study assessed the impacts of habitat origin (saline and non-saline habitats), temperature, and light on drought and salinity tolerances during germination of Salsola drummondii Ulbr., a habitat-indifferent halophyte. Drought tolerance was also assessed for S. imbricata Forssk. Seeds treated with different concentrations of sodium chloride (NaCl) (0 to 1000 mM NaCl) for salinity analysis, and polyethylene glycol (0 to -1.5 MPa for S. drummondii and 0 to -2.4 MPa for S. imbricata) for drought analysis, were incubated at three temperatures and two light different regimes. Seeds of S. drummondii from the two habitats differed in dormancy, germination speed, and responses to light and temperature, which could be considered as environmental cues to determine the proper space and time of germination. The two Salsola L., species germinated better at the lower than at higher thermoperiods. Seeds of S. imbricata tolerated higher drought stress than S. drummondii.