ﺑﺮرﺳﻲ واﻛﻨﺶ ﺟﻮاﻧﻪ زﻧﻲ ﺑﺬور ﻛﺎﺗﻮس(Cynanchum acutum) ﺑﻪ ﺗﻨﺶ ﻫﺎی ﺷﻮری و ﺧﺸﻜﻲ

Two separating experiments was conducted to study salinity and drought stress effects on seeds germination of Cynanchum acutum, in Hakim Farabi sugarcane research institute of Khouzestan in 2014. Experiments were conducted as completely randomized design with four replications. Salinity and drought treatments consisted of: 0(control), 25, 50, 75, 100, 150, 250 and 300 mmol/L of sodium chloride salt and osmatic potentials of PEG solution was equivalent to: 0(control), -0.2, -0.4, -0.6, -0.8, -1, -1.2 and -1.4 MPa. The result showed that the germination percentage had no significant difference with control, in salinity treatments up to 50 mmol/L, and a negligible amount of germination was also observed in 300 mmol/L level. In drought stress treatments, no significant reduction in germination was observed, comparing to control, up to -1.2 MPa level. However, at -1.4 MPa level, germination reduced to 77 percent, that shows high toleranceof this species to drought stress. Also stem length growth was completely stopped, under the salinity stress in 300 mmol/L level. Control treatment, that had no significant difference with 50 mmol/L level, had the maximum stem length. The minimum stem length in drought stress was related to -1 MPa level and the maximum amount was related to control treatment.