Óleos essenciais no controle in vitro de Aspergillus sp. e Penicillium sp.

Abstract

Among the problems that plague Brazilian agriculture, the significant losses caused by grain and seed storage fungi stand out. These fungi, especially the Aspergillus and Penicillium genera, are responsible for producing toxins that directly affect the quality and quantity of seeds and grains. Fungus control is most often done through chemical treatments, which are more effective. However, the damage that this method has caused to human health and the environment has aroused the interest of researchers in alternative treatment methods. Essential oils have antimicrobial potential and have less impact on human health and the environment, showing promise for replacing agrochemicals in seed treatments. Therefore, the present work sought to evaluate the effectiveness of Ocimum basilicum and Cymbopogon winterianus essential oils in the in vitro control of the fungi Aspergillus sp. and Penicillium sp. The concentrations of essential oils used were 0; 0.1; 0.2; 0.4 and 0.8%, and a treatment with the fungicide MAXIM ADVANCED® (positive control). A completely randomized design in a 2 x 5 factorial scheme (two pathogens and five concentrations) was used for the variables, mycelial growth, spore germination and hyphae size; for the variable cumulative mycelial growth, a completely randomized design in a 2 x factorial scheme was used. 6 (two pathogens, five concentrations + fungicide treatment). Ocimum basilicum essential oil was effective in reducing mycelial growth, spore germination and hyphae size of Aspergillus sp. and Penicillium sp. in vitro, demonstrating antifungal potential. Cymbopogon winterianus essential oil was effective in reducing spore germination and hyphae size of Aspergillus sp. and Penicillium sp. in vitro, showing an inconclusive response to the variable mycelial growth. For both essential oils evaluated, as the concentration increased, toxicity to pathogens increased.