Antifungal activity of essential oil and emulsifiable concentrates of citronella and lemon grass against Phomopsis vexans

Abstract

The present study aims to develop eco-friendly Emulsifiable Concentrates (EC) using citronella and lemon grass essential oil (EO) and evaluate its antifungal activity against Phomopsis vexans in Solanum melongena. Among nine prepared formulations, F1 formulation with EO (40%) + vegetable oil (50%) and emulsifier blends (10%) with hydrophilic-lipophilic balance value (12.86) were found suitable for both EO formulations. These formulations (CF1 and LF1) performed well in terms of emulsion stability, cold test, accelerated storage and foam test indicating feasibility for their commercial production. In laboratory studies, at 0.1% concentration, citronella essential oil, lemon grass essential oil and their EC formulations CF1 and LF1 inhibited the growth of P. vexans with EC50 values 0.0087, 0.0098, 0.009 and 0.0126, respectively. Further, under field conditions, CF1 performed better than LF1 formulation in terms of minimum disease severity (32.22%). Hence, EC formulations can be used as natural and eco-friendly fungicide for P. vexans control.