CONGABA Comparação da atividade antifúngica do óleo comercial e do extrato etanólico das folhas de nim (Azadirachta indica Juss) frente a fungos fitopatogênicos

Fungicides are responsible for environmental contamination and are also harmful to human health. The malfunctions caused by these synthetic products have led to the search for alternative control methods, such as substances derived from extracts and vegetable oils. Numerous scientific studies have already found the antifungal potential of oil and neem extracts (Azadirachta indica Juss), and the oil has become a product marketed by numerous brands, suitable for spraying in agriculture. In this context, this work aimed to compare the antifungal activity of commercial oil and the ethanolic extract obtained from neem fresh leaves against phytopathogenic fungi. For this, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (CFM) of both products were evaluated against Fusarium oxysporum, Macrophomina phaseolina, Sclerotinia sclerotiorum and Aspergillus parasiticus at concentrations of 1000 to 15,625 μg.mL-1. Both the oil and the neem ethanolic extract presented antifungal activity, being inhibitory against M. phaseolina in the minimum concentration of 250 μg.mL-1, on F. oxysporum in the minimum concentration of 250 μg.mL-1 (oil) and 500 μg.mL-1 (extract) and both against S. sclerotiorum and A. parasiticus at the minimum concentration of 1000 μg.mL-1. However, only the ethanolic neem extract had fungicidal activity against F. oxysporum and M. phaseolina at a concentration of at least 500 μg.mL-1 and 1000 μg.mL-1, respectively. Thus, the ethanolic extract of the neem fresh leaves presented a potential substitute for neem commercial oil, which makes it advantageous because it can be easily obtained in rural properties, without the need for the use of sophisticated equipment and at a reduced cost, acting on the alternative control of phytopathogenic fungi.