Effects of seed priming with gibberellin on germination of safflower under salinity stress

Salinity is one of the most important factors limiting plant growth and production around the world. Gibberellic acid is known as a strong growth stimulator, effective on seed germination and breaking of seed dormancy in various plant species. In order to study the response of Safflower cultivar Sofeh to salinity stress, a factorial experiment was conducted based on a randomized complete block design with three replications in Pardis Agricultural Research and Education Center, Saveh, Iran. The first factor was salinity at three levels including 0, 100, and 200 mM NaCal. The second factor was seed priming with gibberellin at three levels including 0, 20, and 40 mgl-1. Findings suggested that the salinity and seed priming improved biochemical indexes of proline and peroxidase in the seedlings under study, increasing their mean germination time, germination rate, germination percentage, and chlorophyll contents. Maximum proline contents were observed in the seedlings treated with 200 mM salinity and primed with 49 mgl-1gibberelin, 3.48 mg per gram fresh weight. Maximum mean germination time, germination rate, germination percentage, and chlorophyll contents were related to 0 mM salinity and 40 mgl-1gibberellin at 2.86 days, 26.16%, 76.6%, and 8.05%, respectively. In sum, the findings suggested that priming of safflower seeds with gibberellin under saline conditions improves the plants’ resistance against salinity and their germination and growth.