Effect of seed priming of soybean on germination parameters in vitro and yield and yield components in the field under drought stress

Investigating the effect of seed priming in yield and yield  components of Williams soybean cultivar under drought stress, an experiment was conducted in a randomized block design of split-plot. The experiment was repeated four replicant and it took place at the experimental station of Islamic Azad university of Shahr-e-Ray. The main plots consisted of two treatments (that is, irrigation after 50 and 100 mm evaporation from pan evaporation was the optimum condition and drought stress) and subplot that include the five durations of priming seed ( that is, four times of soaking and drying the seeds for 2,4,6 and 8 hours in the shade without any primings ). A completely randomized design was conducted under laboratory environment with four replications. Priming seeds showed improvement percentage and germination rate under laboratory environment. As was observed in seed germination, seeds were soaked and dried each, for 4 hours with the average of 95/66 percent, had the highest percentage of germination. The lowest germination time was the 4 times soaking and drying seeds in 6 hours each, in shade in 1/29 days. The results showed that it decreased the drought stress, performance, number of pods per plant, seeds per pod, seed weight and harvest index. Priming seed in both irrigation and drought stress caused an improvement in seed yield, seed weight and harvest index. The highest seed yield was gained with four hours retrofitting and in the absence of stress with an average of 4012 kg per hectare.  Also under the drought stress condition, priming caused yield improvements through growth and yield related traits. Accordingly Therefore priming in such environment had significantly better results in 4 hours and as a result of drought stress led to the highest seed yield of 2883 kg per hectare. Consequently the treatment of priming seed can be treated as a way of increasing the soybean seed yield in the different moisture conditions.