Cultivo in vitro de embriões de coquinho azedo (Butia capitata (Mart.) Becc)

Abstract

The experiments were conducted in Uberlândia, Minas Gerais and the fruits of Butia capitata (Mart) Becc were collected in the region of Montes Claros - MG. Different embryo immersion times were tested in the first experiment, using 0.25% chlorine solution for 10, 20 or 30 minutes, and immersed, or not, for 10 minutes in a solution of the fungicide methyl thiophanate at 1.5 mL L-1. There was no need for the use of fungicide for contamination control, and treatment with 0.25 % chlorine solution for 10 to 30 minutes was sufficient. The second experiment was done in a completely randomized design with 8 treatments, 4 replicates and 12 plots. Treatments consisted of the addition of different antioxidants (control - absence of antioxidants; ascorbic acid - 100 mg L-1; PVP - 400 mg L-1 and activated charcoal - 3.0 g L-1) to the MS medium with 75% ionic strength, with or without immersion in ascorbic acid solution (100 mg L-1). The following characteristics were evaluated after 45 days: oxidation (in %), observed as darkening of the embryo structures; germination (in %) and normal plants ( % ), considering as normal plants those emitting both shoot and rootlet, while for germination the presence of any of these parts was counted. The last experiment was done as a 4x4 factorial in a completely randomized design with 16 treatments, 3 replicates and 2 plots. The treatments were characterized by the combination of 4 doses of BAP (0, 0.96, 1.92 or 3.84 mg L-1), and 4 doses of ANA (0, 0.24, 0.48 or 0.96 mg L-1), added to the MS medium with 75% of ionic strength. The following characteristics were evaluated after 110 days: number of leaves; leaf main length (cm), length of the main root; shoot and root dry matter. There was no significant interaction between the measurements of ANA and BAP for any of characteristics evaluated. Greater leaf length was obtained using 0.47 mg L-1 of ANA.