Biocontrol potential of essential oil from Moroccan Ridolfia segetum (L.) Moris

The present study characterized and evaluated the antifungal, nematicidal, acaricidal and repellent activities of Ridolfia segetum essential oil (EO), against the fungus Botrytis cinerea Pers., the nematode Meloidogyne javanica and the mite Tetranychus urticae Koch under laboratory conditions. The EO exerted inhibition of the mycelial growth of B. cinerea with median inhibitory concentration (IC50) of 3.63 μL/mL and 0.92 μL/mL air, under contact and vapor phase conditions, respectively. EO application against M. javanica revealed a strong nematostatic effect on second-stage juveniles (J2) and eggs of the root knot nematode with median lethal concentration (LC50) of 10.37 and 9.26 μL/mL, respectively. The oil was toxic to T. urticae by residual contact with median lethal dose (LD50) of 6005 µL/L and exhibited a repellent effect with a repellency index (RI) of 55%. Results suggest that R. segetum oil has potential to be formulated in biopesticides to control the targeted pest and diseases.