The Study of Effects of Humidity Losses Methods in the Environment and Autoclave on Germination and Dormancy of Lmmature Common Ash (Fraxinus Excelsior L.) Seeds

Ash is one of the valuable species in the north part of iran, particularly in the arid valleys that has settled on the lowlands to high lands areas. In respect of abundance seedling production of this species, a large amount of seeds is needed each year, but large seed bearing occurs every two years in the stable and optimal environmental condition and also ash seeds have morphophysiological dormancy. Therefore clearly in some years we countered to seed deficiency. Good programming for seed collection has a critical role for obtaining success. Because delaying of seed collection cause serious decrease in seedling production amount. In this study effect of humidity losses evaluated in immature seeds on germination percent and humidity losses cause deeping seed dormancy and decrease of germination percent(P