Effects of Seed Priming on Germination Characteristics of Achillea millefolium Seeds under Different Ageing Treatment

The genus Achillea L. (Compositae) widely use as medicinal plant possessing several pharmacological effects due to presence of active compounds. In order to study of seed priming effects on seedling growth of yarrow, a factorial experiment, based on randomized complete design with three replications was conducted under greenhouse conditions in Research Institute of Forests and Rangeland (RIFR) for one year. Experimental factors were a) three Achillea millefolium L. accessions originated from Kordestan (14303), Semnan (21602) and Gilan (27028), provinces, b) five conservation methods including: medium-term storage (Active Collection at 4 °C,10 or 15 years), long-term storage (Base Collection at -18 °C,10 or 15 years), regenerated seeds in open storage 22 °C for2 years (Control) and aged seed under accelerated ageing (40 °C,98% of relative humidity for 48 and 72h) and c) priming treatments including: non- priming (control), osmo-priming (PEG-0.3Mpa), hormonal priming (gibberellic acid at250 and 500ppm).Data collected for seed emergence percent, root and shoot length, seedling length, vigor index, seedling weight and three peroxidase, catalase and superoxide dismutase (SOD) enzymatic activities. Result of analysis of variance showed significant effects of all factors and their interactions for all of seedling traits and enzymatic activities except for SOD (P<0.01).Results also suggested significant differentiation among three accessions of A. millefolium for all germination traits and enzymes activities. Results showed that responses of accessions to aging and priming treatments were different. The data demonstrated that catalase is a key enzyme for seed repair against ageing ROS-induced damage during priming treatment.