Effects of priming on seed germination characteristics and fatty acids content in marigold (Calendula officinalis L.) seeds under UV stress and temperature

In order to investigate the effects of seed priming on seed germination indices and fatty acids of marigold (Calendula officinalis L.) seeds under ultraviolet radiation and temperature, a factorial experiment was conducted in a completely randomized design with four replications. The levels of treatments contained of 8 types of priming (200 and 400 mg.l-1 of gibberellic acid and potassium nitrate, -5 and -10 bar levels of polyethylene glycol, hydroperiming and control), two temperature levels (20 and 25 ° C) and two levels of ultraviolet radiation (0 and 15 minutes with 220 gms with 3 k.Gy intensity). The results showed that the use of gibberellic acid at concentration of 200 mg.l-1 could largely eliminate the harmful effects of ultraviolet radiation. Significant excesses in germination traits such as germination percentage and seed vigour were observed in seeds treated with gibberellic acid. There was a positive interaction of this hormone with other treatments. The highest seed vigour and fatty acids content were observed in 200 mg.l-1 gibberellic acid treatment without ultraviolet irradiation at 20 ° C.