Investigation of suitable seed germination enhancement and breaking seed dormancy treatment of Montpellier maple (Acer monospessulanum L.)

Acer monospessulanum is one of the important forest species in western forests of Iran. Its populations decreased in recent years. Because of embryo dormancy and hard seed coat, its seed has both physiological and mechanical seed dormancy. The optimal treatment for breaking dormancy and seed germination enhancement of this species was investigated. A completely randomized design with 3 replicates were used to compare the effects of 3 and 6 months chilling (4±1°C) on the top of paper or in sand, 2 concentrations of gibbrellic acid (250 and 500 ppm) after stratification, scarification with concentrated sulfuric acid for 10 or 20 min, pretreatment of seeds in alternate temperature (15/ 25°C, night/days) for 3 months in sand before chilling and direct seeding (with or without scarification) in pots and maintaining in natural conditions on seed germination of Acer monospessulanum L.. The results showed that sowing seeds in sand significantly (p<0.01) increased germination rate and the best treatment was chilling for 6 months (33%). Seed germination was not significantly increased by GA₃ after chilling. Sulfuric acid did not show any effect on seed germination. There was not any significant difference between alternate temperatures before chilling and chilling for 6 months. Number of germinated seeds in Acer increased when seeds were scarified and cultured under the natural conditions (35.6% vise 11%). Chilling (6 months) was, therefore, the most effective treatment for germination of Montpellier maple seeds.