Improving germination and biochemical aspects in pumpkin (Cucurbita pepo) seeds deterioration under priming by salicylic acid and ascorbic acid

This study was performed to investigate the effect of pumpkin (Cucurbita pepo L.) seed’s pre-treatment by salicylic acid and ascorbic acid on different aspects of seed germination and biochemical features. A factorial experiment was conducted based on a completely randomized design with three replications. Experimental treatments included two levels of seed maturity (normal seeds and aged seeds) and five levels of priming (control, ascorbic acid 50 and 100 mg/l, and salicylic acid 50 and 100 mg/l). The seed traits were finally measured included the germination percentage, first and second seed vigor index, seedling dry weight, peroxidase and superoxide dismutase activity, electrolyte leakage, soluble protein, and soluble carbohydrate. Based on the results, the seed pre-treatment with 100 mg/l ascorbic acid and salicylic acid could perform the highest germination indices. Moreover, the germination percentage (74%) was improved in aged seeds pre-treated by ascorbic acid and salicylic acid (especially at a concentration of 100 mg/l). Also, the antioxidant enzyme activity was increased while the cell electrolyte leakage was significantly decreased. In total, results indicate, the pre-treatment with salicylic acid and ascorbic acid, not only improved the germination quantity and vigor but also improved the germination quality mainly by the development of carbohydrate and protein content in pumpkin seeds.