تأثیر جبرلین و سرمای مرطوب بر شکست خواب بذر کما .Ferula ovina Boiss

Ferula ovina Boiss. is one of grazing species whose seed germination faces certain problems. The dormancy characteristics of and optimum conditions for seed germination of this species have not been investigated so far. The present research was designed to investigate the effect of GA3 and moist chilling on seed germination of this plant. At first, a factorial the experiment in a completely randomized design with 6 replicates was performed to evaluate the factors: cold period in 0-3 °C (0,3,5,7,9 weeks), GA3 concentrations (0,500,1000 PPm) and time of GA3 (before cold, during cold, after cold). In the second experiment, the effect of cold duration and GA on T50 Ferula seed was investigated in 6 replications. The best treatment was moist chilling for 7 weeks at 3 C or 3 weeks of moist chilling together with soaking in 500 PPm GA3 solution for 12 h. These treatments significantly increased germination percentage and decreased the time of for germination by 50% (T50) compared to control. The addition of GA3, together with cold duration was more effective than its application before cold period, addition of GA3 after cold period, no further increase in germination occurred. Also increasing GA3 concentration (500 to 1000 PPm) did not have any significant effect on the percentage of germination and could not replace the total need for pre chilling. The results showed that Ferula ovina seeds display an endophysiological dormancy that can be released by GA3 and moist chilling treatment.