عنوان مقاله [English]
Because of small and low quality seeds, St Johns wort (Hypericum perforatum L.) have not favorable establishment in the field. In these study effects of different seed enhancement treatments were applied on the seeds and relationship of emergence with germination characteristics and amylase activity were evaluated. A factorial experiment was conducted in randomized ccompletely design with four replications. Osmopriming with Polyethylene glycol 6000 in five levels (0, -3, -6, -9 and -12 bar) were conducted as first factor and application of Gibberellic acid at four concentration (0, 500, 1000 and 1500 ppm) as second factor. Analysis of variance showed that polyethylene glycol, gibberellin and their interaction had significant effects on germination and emergence of St Johns wort seeds. Continuous application of PEG and GA had most favorable effect on germination, emergence, vigor and Amylase activity compared to the control and separate application of them. Concentration of 1000 ppm of gibberellin in -12 bar of osmotic potential caused to highest germination (91.5 %), emergence (80.5 %), seed vigor (32.08) and amylase activity (25.21 starch breakage percentage). While the control showed lowest performance in all measured traits. Correlation analysis showed a positive and significant correlation between seedling emergence of and germination percentage (r=0.89**), seed vigor (r=0.95**) and amylase activity (r=0.92**) of St Johns wort seeds. Based on the results, it is seems that application of priming techniques improve establishment of St Johns wort seeds via increasing germination, seed vigor and amylase activity.