The objective of this study was to evaluate the action of different concentrations of essential oils of three medicinal plants on the mycelial growth, production and conidial germination of Colletotrichum gloeosporioides (Penz.). We used a completely randomized design, in a 5x3 factorial design, being five concentrations (0 µL mL-1, 1 µL mL-1, 3 µL mL-1, 5 µL mL-1 e 7 µL mL-1) x three oils from Lippia sidoides Cham., Cymbopogon citratus (DC) Stapf. and Ocimum gratissimum L., with four replications. The oils were analyzed by gas chromatography with mass spectrometry. There was a significant interaction of concentration versus species on all analyzed traits. The essential oil from C. citratus yielded the highest mycelial growth inhibition at all concentrations. The other oils were not differentiated, except at the concentration of 5µL mL-1, in which the oil of L. sidoides was more efficient that the oil of O. gratissimum. In conidial production and germination, the oil of C. citratus was superior to the oil of L. sidoides and O. gratissimum at the concentrations of 1 µL mL-1 and 3 µL mL-1, as it completely inhibited the production and germination of conidia at the concentrations of 3 µL mL-1 and above. The concentrations influenced all the variables, adjusting themselves to the linear model equation. We observed a decrease in the variables, as the concentrations of the oils tested are increased. The essential oils used have antifungal and fungicidal effect.
Colletotrichum gloeosporioides; vegetable compounds; control of phytopathogens
