FORMULAÇÃO FUNGICIDA NATURAL À BASE DE EXTRATO DE Azadirachta indica PARA USO COMO DEFENSIVO AGRÍCOLA

Research on the application of plant secondary metabolites in integrated pest management is increasing, as the use of these substances can reduce crop production costs, as well as reduce environmental risks and dependence on synthetic insecticides. However, the most widely used methods for insect pest control are still based on the use of synthetic insecticides, which present high risks of toxicity and environmental contamination, as well as high cost. An important phytopathogen for agriculture is the fungus L. theobromae, which is a very aggressive microorganism capable of infecting various plant species and their different organs. The objective of the present work was to develop fungicidal formulations capable of inhibiting the growth of the fungus L. theobromae. Neem extract (Azadiracta indica) formulation was developed with the addition of eucalyptus (Eucalyptus staigeriana), clove (Szigium aromaticum [L]) and citronella (Cymbopogon nardus) essential oil. In vitro evaluation of antifungal activity was used to determine the percentage of mycelial growth (PIC), carried out according to the methodology described by Menten, 1976. The acute toxicity of the formulations was also assessed by determining the LD50 (Lethal Dose 50%) From this study it was possible to infer that the formulations obtained from the ethanolic extract in association with clove and eucalyptus oils have strong fungicidal activities. %, indicating that the essential oils act synergistically with the extract to combat the fungus L. theobromae. Therefore, it was possible to verify that, as well as pure essential oils and crude extract, the formulations have low toxicity.