Ação antifúngica in vitro do óleo essencial de Alfazema Brava (Mesosphaerum suaveolens (L.) Kuntze) frente a fungos fitopatogênicos.

Abstract

Essential oils in the control of diseases caused by phytopathogenic fungi can provide an alternative control to the use of commercial fungicides. Thus, the objective of this research was a phytochemical study of M. suaveolens leaves and evaluation of the antifungal action of essential oil on phytopathogenic fungi. For this, collections of botanical material were carried out to identify and obtain essential oil by hydrodistillation. Laboratory procedures were also performed to determine chlorophylls, carotenoids, flavonoids, anthocyanins and total phenolics for fresh samples. The antifungal action of essential oil was evaluated through in vitro tests with phytopathogens of the genus Colletotrichum (gloesporioides and musae) to verify the speed and inhibition of mycelial growth. The results of the phytochemical study of the leaves indicated considerable levels of flavonoids and total phenolics. In vitro tests showed that the essential oil of M. suaveolens inhibited and reduced the growth of the two Colleototrichum species in all concentrations (100, 250, 500, 1000 μl.100ml-1), to a greater or lesser extent with greater action in C. musae which showed efficiency compared to the commercial fungicide Thiram at concentrations of 250, 500 and 1000 μLml-1.