Effect of priming on seed germination indices and enzyme activity of Alnus subcordata under light and dark conditions

Alder trees as ornamental tree in northern forests of Iran are most used in urban green space. However, its propagation and seedling production is not done in Iran. One of the easy methods of plant propagation is the use of seed. Seed priming technique can be used to improve seed germination. This experiment was conducted in order to study the effects of priming (without priming, potassium nitrate (0.02 and 0.04%, gibberellic acid 50 and 100 mg L-1, water) and Photoperiod (dark and bright) on germination and enzymatic activity of Alnus subcordata. The experiment was carried out in factorial arrangement based on completely randomized design. According to the results, the highest percentage of germination (53%) was observed in seeds primed with 100 mg L-1 gibberellic acid in darkness. The effect of priming on the activity of catalase enzyme was significant at 1% probability level. The maximum peroxidase activity was in the dark and in the treatment of 100 mg L-1 of gibberellic acid.The most activity of this enzyme was observed in seeds primed with gibberellic acid 100 mg L-1. The maximum length of stems in dark and light treatments was 3.8 and 2.7 cm, respectively, at 50 mg L-1 gibberellic acid treatment. The maximum vigor index was related to gibberellic acid treatment. According to the results, the use of gibberellic acid treatment and dark conditions are recommended to improve the characteristics of germination in alder seed.