Effects Of Osmotic Priming On Germination And Vigor Of Zoysia Japonica Seed And Its Mechanisms

Comparison between PEG-osmotic priming and water soaking was studied to determine which was the better treatment to improve zoysiagrass (Zoysiajaponica Steud.) seed germination and seed vigor, and to evaluate the maintenance of priming effects, storage experiment of primed seed was conducted as well. According to dormant characteristic of zoysiagrass seed, seed lots with NaOH scarified to different extent were subjected to priming treatments to detect whether there existed the influences of priming on seed dormancy. Based on mentioned above, some physiological index were also tested trying to reveal the primary mechanisms of priming effects. The main results showed as follows:Priming and soaking could increasing the germination ability of zoysiagrass seed, especially to seed having poor quality, and the effects was more obvious under sub-optimal germination temperature than under optimal temperature. Compared to soaking, priming benefited zoysiagrass seed on germination and vigor much.The -O.lMpa plus 48 hours' osmotic priming treatment (25℃) can be adopted to advance germination rate and synchrony for high vigor zoysiagrass seeds with final germination percentage of above 90% if necessary. The optimal osmotic priming treatments for zoysiagrass seeds with final germination percentage of about 60%~70% were -0.7MPa plus 48 hours' osmotic priming at 25℃, and to those with about 30%~40% final germination percentage, (-0.4 to -0.7 ) MPa plus (24 to 48 ) hours' osmotic priming was the best selection (25℃ ) .The effects of osmotic priming on improving seed germination and vigor could last at least 100 days. And stored in ambient room conditions, it was better in plastic bag than in paper bag for primed and re-dried zoysiagrass seeds.As for partially NaOH scarified zoysiagrass seed, osmotic priming had the function of break seed dormancy.The effects of osmotic priming to zoysiagrass seed were the results of a series of related physiological and biochemical processes that priming treatment brought about concerning many levels, such as gene adjustment, protein translation and seed structure.