The Effects of Seed Priming with Acid Ascorbic on Seed Germination and Morphological Traits of Taverniera cuneifolia under Drought Stress

The species of Taverniera cuneifolia belonging to the family of legominoseae is a perennial species usually growing in the south of Iran. The objective of this study was to evaluate the effects of the drought stress and seed priming using acid ascorbic (AsA) on seed germination of Taverniera cuneifolia in laboratory and seedling morphological traits in greenhouse conditions. This study was conducted in 2015 in Iran. In laboratory, a factorial experiment was conducted using Polyethylene glycol 6000 in drought stress (0, - 4, -8, -16 bar) and priming AsA in four levels (0, 50, 100 and 200 mM) for 24 hours and in the greenhouse, experiment AsA in four levels (0, 50, 100 and 200 mM) and drought stress in four irrigation periods (3, 6, 9 and 12 days). Experimental design was a completely randomized design in four replications with 30 seeds per pots per replication. In greenhouse, seeds were sown in plastic pots in soil. All pots were irrigated until germination stage. Then, drought stresses were applied for 64 days and finally, morphological traits were measured. The data were analyzed and means comparisons were made using Duncan test (P<0.05). Results showed that increasing drought stress caused significant decreases in the seed germination, and morphological traits of T. cuneifolia. The lowest seed germination, shoot length, root length and vigor index were obtained in drought stress of -16 bar. The highest germination rate was obtained in priming seeds in 200 mM AsA and non drought stress treatment. The highest specific leaf area (cm2/g), leaf area (cm2), and dry weight biomass were found in priming seeds in 200 mM AsA. In conclusion, priming with AsA improved the seed germination rate and morphological traits in seedling of T. cuneifolia.