بررسي شكستن خواب و جوانه زني بذر ASTRAGALUS SILIQUOSUS

Study of dormancy breakage and germination in seeds of Astragalus siliquosus.

To evaluate the germination and breaking seed dormancy of Astragalus siliquosus Boiss., an experiment was carried out as a completely randomized design with seven treatments and three replications in Seed Technology Laboratory of Natural Resources Gene Bank, Karaj, Iran. Several treatments, including acid and mechanical scarification and stratification were applied to increase seed coat permeability. Results indicated that about 95% of seed dormancy is due to seed coat impermeability to water and the rest is related to physiological factors. Mechanical scarification with sandpaper was the most appropriate treatment to make the seed coat permeable to water with no adverse effects on embryo. This treatment along with cold stratification removed more than 98% of seed dormancy. Also, stratification of the imbibed seeds increased speed of germination significantly, but had no considerable effects on fresh and dry weights of seedlings. Sulfuric acid, however, increased germination but had maximum percentage of dead seeds. Other treatments had not significant differences with control.