EVALUATION OF SCHIZOLOBIUM AMAZONICUM SEED GERMINATION AS A FUNCTION OF DIFFERENT DORMANCY-BREAKING TREATMENTS

Abstract

Schizolobium Amazonicum, popularly known as Cuiabano Pine or Paricá, is a forest species with accelerated development due to its pioneering nature. It is widely used in reforestation areas to provide conditions for other secondary and tertiary forest species to thrive. Furthermore, it is a species with diverse uses in construction, toys, plywood, and other industries. The seeds have a hard, waterproof seed coat, which naturally makes them very difficult to germinate. Hence, the use of techniques to break dormancy and accelerate the germination process is essential. Mechanical and chemical techniques are among the most common techniques for breaking dormancy in this species' seeds. Given the difficulty of natural seed germination, this study aims to evaluate the effects of different dormancy-breaking treatments, seeking the method that results in the highest seed germination percentage using mechanical, mechanical-thermal, mechanical-chemical, and chemical techniques. Thus, the treatments used were: T0 – Control; T1 – Lateral scarification with a grinder; T2 – Lateral scarification with a grinder + immersion in water at 60°C for 15 minutes; T3 – Lateral scarification with a grinder + immersion in water at 90°C for 15 minutes; T4 – Lateral scarification + immersion in sulfuric acid for 10 minutes; T5 – Immersion in sulfuric acid for 10 minutes. The experiment was implemented in an external laboratory at the Colorado do Oeste Campus of IFRO. The seeds were sown in trays containing washed fine sand and covered with paper towels to maintain seed moisture. The effect of the treatments was evaluated by Seedling Emergence (SE) at ten observation times (one per day). A completely randomized design was used, with two replicates of 40 seeds. Treatments involving mechanical scarification alone or in combination showed the best performance (95% to 100%), while exclusively thermal or chemical methods were less efficient. It is concluded that the species' dormancy is predominantly physical, and that mechanical scarification, alone or in combination with sulfuric acid, is highly recommended for seedling production in nurseries, contributing to sustainable forestry in the Amazon.

DOI: 10.56238/edimpacto2025.051-007