The Effect of Hydropriming, Halopriming and Boiling Water on Seed Germination of Black Locust (Robinia pesudoacasia L.)

Seed priming is the most important technique for increasing the germination power. This study was conducted to investigate the effects of halopriming and hydropriming on improvement of seed germination in black locust (Robinia pseudoacacia L.) in a completely randomized design with 4 replications. Halopriming treatments of KNO3 with concentrations including (100, 250, 500, 750 mM) and hydropriming treatments at three time levels (24, 48, 72 h), and also seed soaking treatment in boiling water for 1 hour as well as control treatment were considered. Results indicated that hydropriming 48 hours, halopriming 100 mM-48 and 24 hour and control treatment had the highest germination percentage. The greatest germination speed was observed in hydropriming 48 hours. The hydropriming 100 mM had the least average germination time. The highest amount of stem (fresh and dry) weight was observed in hydropriming 72 h and halopriming 100 mM-48 hours, respectively. Also, halopriming 100 mM-24 h and hydropriming 72 h showed greatest amount of root (fresh and dry) weight. The highest stem length was related to control treatment. The greatest root length was showed in hydropiming-48 hours and control treatment. Generally, the highest seed vigor index was observed in control and then in hydropriming-48 hours. Application of hydropriming (48 hours) as easy and inexpensive technique can be useful to improve some germination characters like germination speed, and dry and fresh weight of root in black locust seedling.