Atividade fungitóxica de extratos vegetais de plantas nativas do bioma caatinga sobre o fungo Colletotrichum musae, agente causal da antracnose em banana.

Abstract

Anthracnose, caused by the fungus Colletotrichum musae, stands out as one of the most important post-harvest diseases affecting bananas, accounting for considerable losses in the production of culture. In order to control this pathogen, the antifungal effect of native plants from the Caatinga biome in the form of plant extracts was evaluated In vitro, as well as the effects of the concentrations 25%, 50%, 75% and 100% of these extracts on mycelial growth of the fungus Colletotricum musae which causes anthracnose in banana. The hydroethanolic extracts of mastic (Astronium urundeuva [Fr. All.] Engl.), Mimosa (Anadenanthera colubrina var.cebil), Rosemary-of-field (Lippia microphylla Cham), and catingueira [Poincianella pyramidalis (Tul.) L. P. Queiroz], were added to the PDA (potato dextrose agar) at concentrations of 25%, 50%, 75%, 100% and the control contained only culture medium. The evaluations were made by mean of two measurements, daily opposite to the diameter of the colonies at 48, 72, 96 and 120 h after the beginning of the experiment. The experiment was a completely randomized design with four replications. The data were submitted to analysis of variance where the means were compared by Scott-Knott test at 5% probability. The results for In vitro tests showed that the field-of-rosemary extract, at all concentrations tested, was the most effective inhibiting pathogen growth by 100%. With respect to other extracts in general, significant reductions in the diameter of the fungal colonies were observed only when it was used the highest concentration studied. The effectiveness of the fungitoxic action, In vitro, on the development of fungus Colletotricum musae showed that the compounds present in hydroethanolic extracts of the plant species of the Caatinga, presented themselves as potential control for this pathogen.