Metodologia do teste de tetrazólio para avaliação da viabilidade e vigor de sementes de Dialium guianense (Aubl.) Sandwith e Parkia pendula Benth. Ex Walp.

Abstract

The Amazon biome is greatly influenced by its forests, which are of utmost importance for maintaining the natural balance of this space, as well as regulating the climate throughout the planet. However, the ecosystem faces great loss in its biodiversity, since in addition to deforestation, that is, the removal of vegetation from forest areas, the degradation of the environment, with selected cuts or fire, still contributes to the reduction of species present in this ecosystem. The main form of resolution of accelerated deforestation are efficient programs of reforestation of degraded areas, which require productive chains of quality seedlings, which directly involves the viability and vigor of the seeds used in this chain, since they are the main means of propagation of native Amazonian forest species and are key to the success of seedling production. There are several tests for seed vigor and viability, especially the tetrazolium test for its reliable and rapid results and diagnosis not only of the viability but also the vigor of these, allowing producers fundamental knowledge for decisions and correct techniques about the production of seedlings. In this context, the objective of this work was to define an adequate methodology for conducting the tetrazolium test on seeds of Dialium guianense (Aubl.) Sandwith and Parkia Pendula Benth. For the two species, three different concentrations of the tetrazolium solution (0.05%, 0.75% and 0.1%) and three different immersion times (1 hour, 2 hours and 3 hours) were tested. The seeds were classified into three vigor categories and six viability classes. The experimental design used was entirely randomized and with a 3x3 factorial scheme. The results obtained were analyzed by variance analysis and the means of the treatments were compared using the Scott-Knott test, both at 5% significance level. For D. guianense seeds, the most appropriate methods for evaluating the viability of their seeds were immersion in tetrazolium solution at 0.75% and 0.1%, both in three hours of immersion, highlighting the lower concentration by using less chemical, with efficiency. In P. pendula seeds, the concentration of 0.075% also in the immersion time of three hours was the methodology that was closest to the germination test, being indicated for evaluation of the viability and vigor of these seeds.