Efeito de diferentes concentrações do Ácido a-naftal-acético e da kinetina na indução de brotos nos explantes caulinares da warburgia salutaris Bertol. f. Chiov

Abstract

The indiscriminate exploitation of Warburgia salutaris, a plant with high medicinal value, has led the species to the danger of extinction. The development of an in vitro regeneration methodology could help to obtain a large number of seedlings and constitute an alternative to sexual propagation. The sexual propagation is limited by the fact that the seeds rapidly lose their germination capacity as a result of predation by insects.In the present work, whose objective was to evaluate the effect of different concentrations of a-naphthalene-acetic acid and Kinetin in the induction of shoots in stem explants of Warburgia salutaris, stem apices of this plant, originating from mother plants located in the Licuati Forest Reserve, were used as explants. In the laboratory, the explants were washed with running water and disinfected under aseptic conditions in the laminar flow chamber with 70% ethanol and 20% sodium hypochlorite. The inoculation was performed in test tubes (20x100mm) containing 10 ml of culture medium for woody plants (WPM), supplemented with sucrose (3%), agar (1%) and four combinations of phytoregulators. The phytoregulators used were a-naphthalene-acetic acid (ANA) at concentrations of 0.1 and 1.5mg/L and Kinetin (KIN) at concentrations of 1.5 and 3.0mg/L. In the control treatment there was no addition of phytohormones. The culture was maintained in a growth room at a temperature of 27*c, photoperiod of 16/8 hours (light/dark) and irradiation of about 40umol.m-2.s-1. A weekly control was carried out not only to remove the test tubes contaminated by pathogens but also to count the probable shoots and leaves that were formed in each treatment. The early interruption of the test, consequence of the high rate of contamination of the culture by fungus and bacteria did not allow the evaluation of the effect of Kinetin and a-naphthalene-acetic acid in the concentrations tested, to the culture medium reduced the formation of leaves.

(TRADUÇAO NOSSA)