Acaricidal and ovicidal properties of Lippia alba essential oil and its chemical constituents against red spider mite, Oligonychus coffeae Nietner (Acari: Tetranychidae) infesting tea crops.

The red spider mite, Oligonychus coffeae Nietner (Acari: Tetranychidae), is a prevalent mite pest damages tea crops. The present study evaluated the efficacy of L. alba essential oil against O. coffeae. GC and GC-MS analysis of L. alba essential oil revealed geraniol (52.19%) and neral (34.13%) as major compounds. The L. alba essential oil applied at 1500 ppm exhibited 100% mortality of treated mites 48 h after exposure through fumigant toxicity method, while 99% ovicidal activity of essential oil was achieved at 1000 ppm. Similarly, in fumigant bioassay LC₅₀ value against O. coffeae was 87.75 ppm for geraniol and 103.49 ppm for neral at 72 h after exposure. The findings suggest that L. alba essential oil and its major constituents geraniol and neral could be used as eco-friendly acaricide, and can be incorporated as one of the components in IPM after multi-location field trials. [ABSTRACT FROM AUTHOR]