Comparing dormancy breaking treatments in Parkinsonia aculeata seeds

Parkinsonia aculeata is a valuable medicinal plant in traditional medicine adapted to tropical and subtropical arid regions and planted as an ornamental plant. Since seed germination of P. aculeata does not occur quickly, the current research was performed to test different dormancy-breaking treatments on germination characteristics of P. aculeata. Materials and methods: The studied treatments included scarification with sandpaper, H2SO4 (98%), KNO3 (0.2%), soaking the seeds in 90 °C hot water for 15 minutes, Gibberellic acid (250, 500, and 100 ppm), leaching (placing the seeds in running water for 48 hours), a combination of leaching treatment with KNO3, and combination of leaching treatment with Gibberellic acid (250, 500 and 100 ppm). To compare the results, the distilled water was considered as a control treatment. A Completely Randomized Design (CRD) was made with 13 treatments and 4 replications. Results: Results showed significant differences between treatments on germination percent, germination speed, length of root, length of shoot and length of seedling, and index of seed vigor (p<0.01). The seeds had more than 85% dormancy, and applying to leach (germination percent, 75%) and scarification treatments (70%) as well as boiling water (57.5%) had the highest effect on releasing the seed dormancy compared to control (15%). Conclusion: Since this plant’s establishment problems are the seed dormancy period, using leaching for 48 hours will help in the germination improvement of P. aculeata. Copyright© 2021, the Authors | Publishing Rights, ASPI. This open-access article is published under the terms of the Creative Commons Attribution- NonCommercial 4.0 International License which permits Share (copy and redistribute the material in any medium or format) and Adapt (remix, transform, and build upon the material) under the Attribution-NonCommercial terms.