Avaliação da viabilidade de sementes de Aspidosperma pyrifolium Mart (Pereiro).

Abstract

In the Caatinga, semi-arid region, the plants underwent physiological adaptations to vegetation under conditions of high temperatures and water deficiency. In this region are endemic species with potential still little studied. Among the species of timber and ecological importance, there is Aspidosperma pyrifolium Mart., Popularly known as Pereiro. The evaluation of the physiological quality of seeds can be performed through feasibility tests such as germination test and tetrazolium test, and it is necessary for Pereiro. The objective of this work was to evaluate the viability of Aspidosperma pyrifolium seeds by standard germination and Tetrazolium tests. In the first, the effect of substrates and temperatures on seed germination was tested, totaling 15 treatments. Seed viability through the tetrazolium test was tested using two soaking times (8 and 10 hours), two immersion times (3 and 6 hours) and tetrazolium solution concentrations (0.075%, 0.5% and 1% ), Using a completely randomized design, in the 2x2x3 factorial arrangement. In the germination test it was observed that the paper roll and vermiculite substrates had a statistically equal performance. The highest percentages of germination were obtained at constant temperatures (25 and 30ºC) and alternated (25-30ºC). In the tetrazolium test, the imbibition and concentration factors alone were decisive in the results. The imbibition time of 10 hours presented better results, regardless of the immersion time and the concentrations. The joint analysis of the studied factors shows the imbibition time of 10 hours with the solution concentration of 0.075% as ideal because it is more economical. It was verified that both tests are efficient for evaluating the viability of Pereiro seeds.