MÉTODOS PARA SUPERAÇÃO DA DORMÊNCIA EM SEMENTES DE Garcinia gardneriana (Planch. & Triana) Zappi

Abstract

Garcinia gardneriana is a native tree species of the Atlantic Forest biome with commercial potential, industrial application, medicinal, ornamental and timber, which seeds have difficulties on germination. In this sense, the objective of the present study was to evaluate different methods to overcome dormancy efficiently and at low cost to promote rapid and uniform seed germinations of this species. In order to study the influence of different methods to Garcina gadneriana overcome dormancy, the following treatments were tested: control, intact seeds without any treatment (T1); seeds without seed coat (T2); seeds without seed coat, followed by immersion in a solution of gibberellic acid (GA3) 500 mg.L-1 for 24 hours (T3); seeds without seed coat, followed by immersion in a solution of potassium nitrate (KNO3) at 0,2% for 24 hours (T4); seeds without seed coat, followed by laminating at 10°C for 120 hours (T5); seeds with seed coat and soaked in solution of potassium nitrate (KNO3) at 0,2% for 24 hours (T6); stratifying the seeds subjected to 10°C for 120 hours (T7); seeds scarified with sandpaper to mass nº 80 opposite the hilum (T8). For dormancy overcome were evaluated: total emergency, first emergency count, emergency speed index, mean emergency time, length and dry weight of seedlings root and seedlings root. The removal of the seed coat favors the emergence of more vigorous seedlings derived from Garcinia gardneriana seeds, so exhibit dormancy coats (exogenous). The seed soaking in gibberellic acid solution can accelerate the emergence speed index but does not influence the mean emergency time. It is recommended as treatments to dormancy overcome of Garcinia gardneriana, the seeds without seed coat, followed by immersion in a solution of gibberellic acid (GA3) 500 mg.L-1 for 24 hours or only seeds without seed coat to be a more practical treatment.