Potential use of lemongrass essential oil as fungicide against Aspergillus brasiliensis and as post-harvest protectant of wheat

Resumo

Fungi are among the main responsible for damage and loss in stored grains, its control has been done through synthetic substances, which are harmful to man and the environment. Brazil, one of the leading countries in agriculture, has optimal environmental conditions for the development of mycotoxigenic fungi. Most of the synthetic chemicals used as preservatives have often been realized to be toxic to humans and also cause adverse environmental effects. Thus, it is necessary to search for alternative methods of controlling. In this study the aimed was to evaluate the efficacy of lemongrass essential oil in the control of the Aspergillus brasiliensis. In vitro and serial microdilution tests were carried out at different concentrations of essential oil and citral, which corresponds to 72% of the total oil composition. Inhibition of fungal growth on contaminated wheat grain was evaluated. The in vitro test results showed that the essential oil has fungicidal potential at concentrations from 0.6 μL mL^-1, the minimum inhibitory concentration was determined at 0.8 μL mL^-1. The tests with citral showed fungal control at concentrations from 0.6 μL mL^-1 onwards. For wheat grain, fungal growth inhibition was obtained at the concentration of 1.6 μL mL^-1. The essential oil of Cymbopogon flexuosus showed fungicidal activity against the fungus Aspergillus brasiliensis.