Like many species within the Fabaceae family, Sesbania punicea L. seeds experience seed coat dormancy, affecting their germination from a hard shell coating the seed, preventing water absorption and gaseous exchange into the seeds. The presented research sought to overcome the outer dormancy phase in Sesbania punicea seeds by treating them with two concentrations of sulfuric acid (50% and 98% H₂SO₄) for periods of 0, 10, and 15 minutes and soaking in hot water (without, with) for 24 hours. The results revealed that seed pretreatment of immersion in sulfuric acid at a 98% concentration was significantly superior to the 50% and showed the highest mean values for the studied parameters, germination percentage, seedling height, stem diameter, leaves per seedling, and shoots dry weight at 78.33%, 61.61 cm, 5.79 mm, 31.27 leaves/seedling, and 7.32 g, respectively. In the same line, the immersion in sulfuric acid for 15 minutes was superior compared with 10 minutes, providing the highest values for the same traits at 87.04%, 64.08 cm, 6.16 mm, 32.08 leaves/seedling, and 8.12 g, respectively. The hot water treatment was notably dominant to the one without soaking and exhibited the maximum values for the above traits (78.55%, 59.83 cm, 5.94 mm, 31.05 leaves/seedlings, and 7.32 g, respectively). The interaction effects of three factors (immersion in 98% sulfuric acid for 15 minutes and soaking in hot water) excelled other treatments for the traits, i.e., germination rate (99.30%), seedling height (71.00 cm), main stem diameter (7.28 mm), leaves/seedling (36.66), and shoot’s dry weight (11.42 g). The most remarkable achievement was that chemical scarification using sulfuric acid and hot water, either individually or in combination, proved effective in breaking the seed dormancy of Sesbania punicea.

Keywords: Sesbania punicea L., seed dormancy, sulfuric acid, hot water, germination, growth traits

Key findings: For better germination and early growth of Sesbania punicea L. seedlings, the combination of seed immersion in 98% sulfuric acid for 15 minutes and soaking in hot water for 24 hours proved recommendable since it leads to an increase in the germination percentage from 36.9% to 99.3%, enhancing the growth parameters.