Effect of hydropriming and seed aging on seed germination and biochemical characteristics of pinto bean (Phaseolus vulgaris) seed under salt stress

This study was conducted to evaluate the effect of hydropriming and seed aging on germination and enzymatic properties of pinto bean under salinity stress as factorial based on a completely randomized design with four replications. Two groups of seeds (i.e., non-aged and aged seeds), two hydropriming treatments (i.e., hydro primed and unprimed seeds) and six salinity treatments (i.e., 0, 2, 4, 6, 8 and 10 dS/m) were the experimental factors. The results showed that the highest mean time and percentage of germination, plumule length and vigor were observed in the control (i.e., distilled water) and hydropriming treatments. Maximum root length and percentage of seedling water were obtained in the control (i.e., distilled water) and aged seed treatments. In addition, in terms of radicle dry weight, the highest amount was observed in salinity of 4 dS/m and non-aged hydro primed seeds. The highest plumule dry weight was observed in salinity of 6 dS/m and allometric index in salinity of 8 dS/m for non-aged seed and aged seed without hydropriming, respectively. An increase in the levels of salinity stress and aging the seeds increased the malondialdehyde and reduced the activity of germination, mean time and germination percentage, and seedling growth. Seed hydropriming reduced the peroxidation of the cell membrane and generally improved the speed and uniformity of germination, aged and natural seeds vigor under both salinity and optimum conditions. As a result, hydropriming can increase the tolerance of bean seeds to salinity at the germination stage and increase the germination capacity of stored seeds for cultivation.