Avaliação dos tratamentos térmico-úmido e mecânico na quebra de dormência em sementes de Peltophorum dubium (Spreng.) Taub. (Fabaceae)

Abstract

The present study evaluates effective methods to overcome physical dormancy in seeds of Peltophorum dubium (canafístula), a species of significant ecological and economic importance in Brazil. Mechanical scarification (abrasion with sandpaper for 2 seconds) and hot water immersion (80°C for 15 minutes and 100°C for 5, 10, and 15 seconds) were tested and compared to an untreated control. The results showed that mechanical scarification and immersion in water at 100°C for 15 seconds were the most effective methods, promoting germination rates of 88% and 89%, respectively, with a statistically significant difference (p < 0.01) compared to the control. The imbibition curve confirmed greater water absorption in treated seeds, with mass gains of 64.62% (scarification) and 68.99% (immersion at 100°C for 15 seconds). It was concluded that both methods are viable for breaking dormancy, with hot water immersion being an economical and efficient alternative for large-scale seedling production. The study contributes to advancing dormancy breaking techniques for this species, which is essential for reforestation and environmental conservation projects.