Blêndali Peres Cardoso
Abstract:
In the aim to study seed germination and to induce callus in jabuticabeira (Plinia cauliflora) leaf explants to characterize their development. In the first experiment, jabuticaba seeds were planted in a greenhouse after 24 hours of immersion in different concentrations of GA3 (0; 250; 500; 1000 and 2000 mg.L-1). Were evaluated: percentage of emergence, shoot size and number of leaves. The experimental design was DIC with 5 treatments and 24 replications. In the second experiment, greenhouse plants served as explant source to test different concentrations of Polyvinylpyrrolidone - PVP (0; 0.5; 1.0; or 2) combined with C.A. (Activated Carbon) at concentrations 0; 2 or 4% and inoculated in MS medium. The design used was the DIC with 4 x 3 factorial arrangement and 15 repetitions. In the third experiment, greenhouse leaf explants were inoculated in MS medium supplemented with 2,4-D (0; 1.0; 2.0 and 4.0 mg.L-1) and BAP (0.0; 0 0.1 mg.L-1) in all possible combinations. After 30, 45 and 60 days the presence or absence of callus at the explant base was evaluated. The design used was the IHD with factorial arrangement 4 x 3 and 20 replications each treatment. In the fourth experiment, greenhouse explants were inoculated in MS medium supplemented with ANA (0, 1.0, 2.0 and 4.0 mg.L-1) and BAP (0.0, 1.0 and 2). 0.0 mg.L-1) in all combinations. After 30, 45 and 60 days the presence or absence of callus at the explant base was evaluated. The design used was the DIC with 4 X 3 factorial arrangement and 20 replications. The data were submitted to analysis of variance, being the averages compared by Tukey Test at 5% of significance or compared through models at 5% level. For the anatomical analyzes, calluses from 15 treatments using 2,4-D and BAP were fixed on slides and visualized in a camera-coupled photonic microscope. GA3 increased the emergence percentage by 20% in the pre-germinative treatments of 1000 mg.L-1 and 2000 mg.L-1 of the regulator for 24 hours. In addition, 1000 mg.L-1 treatment favored shoot growth and increased leaf number. To decrease oxidation, a 2% concentration of active charcoal in the culture medium combined with 2.0 mg.L-1 PVP is indicated. In order to obtain callus, the use of MS medium without the addition of growth regulator is indicated, an important result to reduce the costs of using regulators and to obtain callus. However, further studies are needed for callus induction in jabuticaba tree (Plinia cauliflora).
