Alternative control of phytopathogenic bacteria with essential oils of Elionurus latiflorus and Cymbopogon flexuosus

Abstract

The use of hazardous chemicals has become a common practice to control diseases that affect agricultural production. In this scenario, society is challenged to increase food availability while reducing pesticide use, which causes damage to health and the environment. In this sense, essential oils appear as a promising alternative to reduce the use of pesticides, since they are plant-derived compounds. This study aimed to identify the main chemical components and evaluate the in vitro antimicrobial potential of essential oils of the Brazilian species Elionurus latiflorus and the exotic species Cymbopogon flexuosus against the phytopathogenic bacteria Xanthomonas axonopodis pv. phaseoli, Ralstonia solanacearum, Pectobacterium carotovorum pv. carotovorum and Pseudomonas syringae pv. tomato. The main component identified of the essential oils was citral at the concentrations 65.38% for E. latiflorus and 71.6% for C. citratus. The analysis of the antibacterial activity of the essential oils showed effect against all bacteria analyzed when compared to the antibiotic gentamicin. The antibiotic produced inhibition zone diameters from 11.30 to 20.67 mm, while the essential oils produced the inhibition zones from 51.22 to 90 mm and pure citral around 86 mm. MIC values for essential oils were found between 25 and 200 µL/mL and MBC between 100 and 400 µL/mL. The study showed that the oils have inhibitory effect on the microorganisms tested.