Nanoemulsion of Foeniculum vulgare essential oil: A propitious striver against weeds of Triticum aestivum

Essential oil based bioherbicides are topic of interest for the new era agriculture because of growing concern worldwide to develop herbicide with low environmental impact. In the present study, oil in water nanoemulsions of fennel (Foeniculum vulgare Mill.) essential oil were formulated by ultrasonic emulsification method and evaluated for herbicidal potential against Phalaris minor Retz., Avena ludoviciana Durieu, Rumex dentatus L. and Medicago denticulata Willd through Petri dish bioassay. The germination of P. minor, A. ludoviciana, R. dentatus and M. denticulata was totally inhibited at concentrations 0.4, 0.3, 0.3 and 0.05 wt%. Major constituents of F. vulgare essential oil, estragole, anethole and binary mixture did not completely inhibit the germination of the tested weed species even at highest concentrations. Nanoemulsions having 0.05 and 0.01 wt% F. vulgare essential oil were spherical in nature with average size below 130 nm and have good stability to centrifugation and dilution. The formulated nanoemulsions were clear and transparent even after 30 days of storage at ambient temperature. Nanoemulsions were more effective and completely inhibited the germination of P. minor, A. ludoviciana, R. dentatus and M. denticulata even at low dose of 0.05 wt% by adversely affecting the physiological processes like membrane leakage and reactive oxygen species mediated cellular damage. Nanoemulsions of F. vulgare essential oil have bioherbicidal properties and can contribute to the development of alternative tool for sustainable management of weeds.