Effect of osmo and hydro-periming on germination characteristics and seedling growth of corn under drought stress condition

In order to study the effects of priming on germination indices and seedling growth of corn under drought stress condition, a factorial experiment based on randomized complete blocks design with three replications was conducted at Physiology Laboratory of Islamic Azad University, Ardabili Branch, Ardabili, Iran, during 2015. Experimental treatments including drought stress in four levels (Zero, -4, -8 and -12 bar) and five pre-treatment including polyethylene glycol, with concentrations of 5 and 10 percent, potassium nitrate with concentrations of 1 and 2 percent, water as hydropriming and control. The results showed that with increasing drought stress, germination components including germigation percentage, speed and germination rate index and radicle length, plumule and seedling, fresh and dry weight radicle to plumule (R/S) decreased and mean germination time, increased. Maximum radicle length, plumule, seedling and germination index was obtained by potassium nitrate pretreatment with 1 percent concentration. Maximum ratio of dry weight and root to shoot (R/S) under the interaction of stress × priming were by potassium nitrate priming with concentrations of 1 percent, and polyethylene glycol with concentrations of 10 percent. Maximum germigation percentage and speed under the interaction of stress × priming by potassium nitrate priming with 1 percent concentration. According to the results, seeds treated with (KNO3) 1% were the best and the most effective treatment for germination indices and seedling growth of corn.