Carposeminal biometrics and germination of Lafoensia pacari A. St. Hil. (Lythraceae) exposed to different concentrations of GA3

Abstract

Growth regulators improve seedling performance, accelerating the emergence rate and expanding the physiologic potential of the seeds even under adverse conditions. The aims of this study was carposeminal biometrics and evaluate the influence of GA3 at different concentrations, in overcoming seed dormancy Lafoensia pacari A. St. Hil., a tree species of savanna and medicinal interest. Biometrics has been used for 100 fruits and 100 seeds, measuring the length, fruit diameter and the operculum. The seeds were characterized by the average number per fruit, weight of 1000 seeds, besides the length, width and thickness, also made to the embryo. The treatments were: distilled water and GA3 at 5, 10 and 20 mg.L-1, added to four sets of 100 seeds each. The dry seeds on paper towels were placed in groups of 25 units in four Petri dishes with filter paper and 10 mL of distilled water, kept in an incubator B.O.D. at 25 ° C and white fluorescent light ?mol.m-2.s-1. The data were used to calculate the Germination Percentage (G%), Germination Speed Index (GSI) and Mean Germination Time (TM), and the results submitted to linear regression analysis. The carposeminal biometrics obtained shows the relation of the fruit and seeds with the dispersion autochory/anemocoric and can serve as a tool for specific differentiation. The increasing concentrations of GA3 positively influenced the Percentage and Germination Speed Index and negatively Mean Time Germination.