Seed Dormancy in Rheum ribes L. Collected from Natural Populations in Turkey

Rheum ribes L. is a medicinally import perennial wild plant species. The aim of this study was to investigate the effects of some breaking dormancy treatments on R. ribes seeds. Mature seeds were collected from naturally growing populations in and around Van, Turkey. Seed germination potentials were tested for scarification, H2SO4 (5%, 10%, 20%, 50% and 75%), stratification period (10, 15, 20, 25 and 30 d at 4 ° C), GA3 (0, 100, 250, 500 and 1000 ppm), GA3 + stratification period (500 ppm GA3 + 4 C at 10, 15, 20, 25 and 30 d), CaCl2 (0, 5, 10, 15 and 20 mM ) and KNO3 (0, 5, 10, 15 and 20 mM) in dark and light conditions. The results showed that the best condition for germination was achieved in light. In dark conditions, scarification, H2SO4, GA3, CaCl2 and KNO3 treatments had lower percentage of germination than light. The highest seed germination percentage (70.0%) was obtained by combinational treatment of stratification period at 4 C for 25 days and 500 ppm GA3 in light. The lowest percentages of germination were obtained in seeds with CaCl2 and KNO3 (20.3% and 14.7%, respectively) in the dark. Keywords : Rheum ribes, Seed germination, GA3, Stratification, Dormancy DOI : 10.7176/JSTR/5-2-22