Adequação dos testes de condutividade elétrica e envelhecimento acelerado para sementes de Handroanthus impetiginosus (Mart. ex DC.) Mattos

Abstract

Handroanthus impetiginosus (Mart. Ex DC.) Mattos Also popularly known as ipe-purple, belonging to the Bignoniaceae family, it is a tree-sized species that can reach 20 to 35 m in height and has an economic value of wood, medicinal, pharmacological and ornamental. Seed vigor is allowed by a set of characteristics or properties that determine the physiological potential, that is an ability to perform properly when exposed to different environmental conditions. Due to the low viability of the auxiliary seeds in the research of this species, this work had as adequate objective the electrical and accelerated conductivity tests to evaluate the vigor of H. impetiginosus seed lots. For the adequacy of the massal electrical conductivity test, two seed drops (25 and 50 seeds), two volumes of distilled water (75 and 100 mL) and seven soaking drops (0, 3, 6, 12, 24, 48 and 72 hours). The suitability of the accelerated aging test was performed in two steps, the first was the optimization of seed incubation (seeds from five batches were subjected to traditional accelerated aging at 42 ºC during 0, 24, 48, 72 and 96 hours). incubation). In the second stage, ten seed lots were submitted to accelerated aging, using a methodology prescribed in the literature for genus species, at 40 ºC during 48 and 72 hours of exposure. Data analysis was performed by univariate statistics using ANOVA and Kruskal-Wallis (p <0.05), applying media test (Tukey at 5% probability level) when statistics were used. Observe to test electrical conductivity with 50 seeds packed in 100 mL of distilled water, ranking at four vigor levels. The accelerated aging test is efficient to evaluate the vigor of different seed lots at 42 ºC / 96 hours. A 40 ºC methodology was effective to confirm the lots that presented low viability since the germination test.