investigation of seed germination characteristics and recovery of gerrmination in the haloxylon aphyllum under different temperature and salinity conditions

haloxylon aphyllum is one of the most important species in sandy and saline areas in deserts, and some ecophysiology characters for viability in unfavorable condition have evaluated in this species. seed germination is the critical stages in life cycle for species survival. in this study investigated salinity and temperature stresses on percentage and velocity of germination using six salinity treatments (0, 100, 200, 300, 400 and 500 mm/i naci) under four different temperature regimes (20:10, 30:10, 25:15 and 35:25 dc). the results showed that seeds could germinate at very high salt concentration (500mm). however, highest germination percentage was obtained in distilled water and thermoperiod 20:1cfc. increased on salinity and temperature caused decreased of percentage and velocity of germination. seed germinated rapidly and no significant change in germination was noticed after 10d. recovery of seed germination investigated when seeds were transferred to distilled water. the results indicated that recovery percentage was high in seeds were transferred from very saline treatment with lower temperature.