DORMANCY OVERCOMING OF Schizolobium amazonicum Huber ex Ducke. (CAESALPINOIDEAE) SEEDS

Abstract

Paricá is a large tree, reaching between 15 and 40 m in height and 50 to 100 cm in DBH (diameter at breast height), when measured at distance of 1.3 m from the ground. Most leguminous species, such as paricá, have exogenous integument-type dormancy. Therefore, the aim of this work was to evaluate the germination of Schizolobium amazonicum seeds collected in the northeastern region of the state of Pará. Treatments to overcome dormancy were: (T0) control (without treatment); (T1) - immersion in water at 100 °C during 10 m; (T2) manual scarification with # 40 sandpaper at the top of the seed, opposite to the embryo; and (T3) mannual topping. For the germination of S. amazonicum seeds, tegument scarification with sandpaper showed to be the most effective pre-germinative treatment, with higher germination and normal seedlings percentage. This technique has low cost and is easy to be applied by nurserymen.