Effect of seed priming on germination and morphophysiological traites of Rice transplants (Oryza sativa L.cv. Hashemi) under different moisture regimes

Two separate factorial experiments based on the completely randomized design were conducted at the Research Center for Plant Sciences, Ferdowsi university of Mashhad. In the first experiment, the effect of 0, -2, -4, -6, -8, and -10 bar of moisture regimes with three priming levels including control (without priming), halo priming by calcium chloride, and hydropriming were investigatedon the seed germination of rice. In the second experiment, the seeds primed similar to the first experiment were cultivated in the pots filled with sand, being under five levels of moisture regimes including control (filed capacity), 20, 40, 60, and 80% of field capacity. After 28 days of cultivation, some morphophysiological traits were measured. The results of the first experiment showed that under low moisture regimes the germination traites were negatively affected. However, under some moisture regimes, the use of priming improved the germination rate and percentage, and increased dry weight of radicle and hypocotyl. It was also found that improving effects of hydropriming was more than halopriming. In the second experiment, low moisture regimes significantly decreased seedling height, shoot dry weight, leaf area, root area and diameter, water relative content, and membrane stability index. Under this condition, seed priming treatment did not positively affect these traits, butincresedstomatal resistance and chlorophyl conten.According to the results, it seems that both under control and low moisture regimes the use of seed priming, specially hydropriming, can be beneficial for Riceseed germination.