Performance of distinct strategies on overcoming dormancy in Senna obtusifolia seeds

Abstract

Senna obtusifolia presents structures favorable to the effects of the dormancy phenomenon, presenting low germination rates for a certain period. This panorama can be solved by the dormancy-breaking process, which is caused by the exposure of the seed to adverse conditions that stimulate the germination process. Accordingly, this study aimed to evaluate the efficiency of different methods to overcome dormancy in Senna obtusifolia (L.) H. S. Irwin & Barneby seeds. A completely randomized design (CRD) was the experimental design adopted, with four treatments and eight replications of 25 seeds. The treatments consisted of mechanical scarification, water imbibition, and immersion in hot water. In this study, a statistically significant difference was seen between treatments for all parameters, where the treatment under mechanical scarification was the most effective for promoting germination (99 ± 1.51% of germinated seeds). Furthermore, the treatment presented the most promising results for average shoot length (ASL) (43.95 ± 8.66 mm), root length (ARL) (28.09 ± 5.27 mm), total fresh mass (MF) (1.97 ± 0.10 g), and total dry mass (MS) (0.37 ± 0.03 g). The mechanical scarification of seeds favored germination and this treatment was the most efficient for the process of overcoming the dormancy of S. obtusifolia seeds.