Seed priming effects on germination and seedling growth of tall wheat grass (Agropyron elongatum) under control and drought stress conditions

Seed priming could be as a way to improve seed germination behavior under moisture stress conditions. This experiment was carried out to determine priming effects on seed germination of tall wheat grass (Agropyron elongatum) under control and drought stress (Ψ=-0/8 bar) conditions. Two 3-replicated factorial experiments based on CRD design were carried out in 2009. In control experiment, seeds were primed in -4, -8, -12, -16, -20, -23, and -25 bar polyethylene glycol (PEG) and urea as well as distilled water (hydropriming) for 8, 12, 16, 20 and 24 hours at 25°C. Seed priming increased germination percentage, germination speed, seedling length, seedling dry weight, root/shoot ratio while decreased mean germination time. In this study, increasing priming duration and osmotic potential of priming solution had negative effects on measured characteristics. The most promising control seed treatments including urea and PEG with -4 and -8 bar as well as hydropriming for 12 and 24 hours were advanced to drought stress experiment. Also, it was shown that priming with urea had better results compared toother treatments. It is concluded that seed priming treatments with fertilizers may serve as an appropriate treatment for advancing germination under optimum and drought stress conditions.