Carposeminal morphometry and germination of Tabebuia impetiginosa (Mart.)Standl. pre-soaked in different periods of exposure and concentrations of GA3

Abstract

Tabebuia impetiginosa occurs widely in Brazil and due to the characteristics of its seeds has a low rate of germination. This study aimed to perform the carposeminal morphometry and evaluate the germination of this species by the pre-soaking seeds in different periods of exposure and GA3 concentrations. We tested, at 30° C, ñve concentrations (5, 10, 20, 40, and 80 mg.L-1) and three pre-soaking periods (60, 120, and 180 minutes). We evaluated the germination, the Germination Velocity Index (GVI), Mean germination Time (MT) and Deterioration Seeds percentage (DS). The biometric characteristics of fruits and seeds refer to anemochoric. Gibberellin stimulated germination in combination of 40 mg.L-1 or 80 mg.L-1 with 60 minutes of soaking, inhibiting it when that time was exceeded. Aperiod of 120 minutes at concentrations of 20 and 40 mg 1-1 increased the Germination Velocity Index. High concentrations of GA3 to 180 minutes caused further deterioration of seeds.