Abstract:

Water characteristics of Sabina vulgaris were studied under drought stress using pressure_volume technique and combining investigations in field and experiment in greenhouse. Investigations in field were made by sampling at upper and lower of dune where soil water content was different in Mu Us Sandy Land. Three treatments of control,light stress,strong stress (osmotic potential of culture solution was 0.0,-0.1,-0.3 Mpa, respectively) were set up in water cultivation system in greenhouse of Okayama University in Japan. The results showed that osmotic potential at turgor loss point( ψ_s) and water potential at water saturation point (ψ_w)decreased in Mu Us Sandy Land. However,bulk modulus of elasticity(ε ) and rate of bound water in cell (V_p/V _o) increased under drought stress. In greenhouse, ψ_s and ψ_w got small, ε and V_p/V _o became big. It was concluded that drought resistance of S.vulgaris could be varied and improved by drought training. Diurnal changes of water potential of S.vulgaris growing in Mu Us Sandy Land,and relationship between the osmotic potential of culture solution and parameters of water characteristics under drought stress were discussed.

Key words: Sabina vulgaris, Drought stress, PV technique, Water potential, Osmotic adjustment