The induction of seed germination using sulfuric acid, gibberellic acid and hot water in Robinia pseudoacacia L.

ABSTRACT: The seed germination is the limiting factor of the culture of Black locust (Robinia pseudoacacia L.), a tree with universal importance for various utilizations. With the aim of obtaining the best treatment for the breaking down of seed dormancy in Black locust, the present research was conducted. Three levels of H2SO4 (0, 50 and 90%v/v) for 30 minutes, gibberellic acid (0, 0.5 and 1mM) for 48 hours and hot water of 85?C (0, 20 and 40S) were used. The effects of single and combined applications of H2SO4, gibberellic acid (GA) and hot water on seed germination rates were evaluated on the basis of completely randomized design in 27 different treatment groups. The applied treatments had enhancing effects on seed germination as well as seedling growth. However, the application of GA treatments only did not resulted in significantly changes and hot water or H2SO4 treatments, especially the 2nd ones, were more effective than the GA ones. As the best results were observed in HW20-A98-GA0.5 and HW20-A98-GA1 treatment groups, the promoting effects of hot water and/or H2SO4 on seed germination as well as seedling growth were accelerated using GA applied treatments. According to the obtained results from the present research, the combined applications of sulfuric acid, hot water and GA could desirably promote seed germination rates as well as seedling growth of black locust tree.