Avaliação da viabilidade de sementes de coração- de-negro (Poecilanthe parviflora Benth. - Fabaceae-faboideae) pelo teste de tetrazólio

Abstract

The increasing demand for Brazilian tree species seeds has been followed by the raise of the necessity to develop methods to evaluate seeds viability, mainly due to fast tests, as such as the tetrazolium. Poecilanthe parviflora (coração-de-negro) is a Brazilian tree species used in forest restoration. However, there is no established test to determine its seeds viability. So, the goal of this research was adequate the tetrazolium test to determine the seeds viability of this species. After preliminary studies, the seeds were pre-conditioned by their immersion in water, until they reach the moisture contents 30% and 40%, and hydrated between papers previously soaked with water, until they reach the moisture content 40%. After the pre-conditioning, seeds coats were removed manually and the embryos were immersed in 0,075% tetrazolium solution for 90 minutes, at 40°C. Tetrazolium test results were compared with the ones obtained in the germination test. The results indicated that the tetrazolium test can be used to evaluate P. parviflora seeds viability, mainly by the seeds immersion in water until they reach the moisture content 40% remove the seed coat and stain the embryo in 0,075% tetrazolium solution for 90 minutes at 40°C.