Tratamentos pré-germinativos para superação da dormência de sementes de Sterculia striata A. St. Hil. Naldin

Abstract

Sterculia striata A. St. Hil. & Naudin. is a native species that is used in reforestation and urban forestry. Displays hard seeds, consisting of problem for the nursery, since their hard seed coats and waterproof hinder and delay germination. This study aimed to determine the effect of pre-germinative treatments in the process of germination of Sterculia striata. The seeds were subjected to six treatments: control - intact seeds (T1), mechanical scarification with sandpaper. 80 opposite the micropylar (T2) with sulfuric acid concentrated by 15, 45 and 60 minutes (T3, T4 and T5 respectively) scarification and then immersion in water for 24 hours (T6). The characteristics evaluated were: seedling emergence, emergency first count, speed of emergence, as well as length and dry mass of shoot and root of seedlings. The scarification with sandpaper number 80 on the opposite side of micropylar favors the percentage of seedlings in the first count, and recommended rapid and uniform emergence of seeds of Sterculia striata.