Acaricidal Potentials of some Essential, Mineral and Plant Oils against the Predacious Mite Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae)

The direct toxicity of some essential, mineral and plant oils to the eggs and females of the predacious mite Neoseiulus cucumeris (Oudemans) was tested in the laboratory. Sweet basil oil was the most toxic essential oil to females N. cucumeris, while sweet marjoram oil was the least toxic one (LC50=2.315 and 7.021%, respectively). In contrast, rosemary oil was toxic to eggs of N. cucumeris, while sweet basil oil was the least effective oil against predator eggs (LC50 = 2.695 and 11.950%, respectively). The mineral oil capl-l 1was the most toxic one to adult females (LC50= 0.849%) while natur'l oil was the least (LC50= 4.691%), respectively. In contrast, natur'l oil was proved to be highly toxic to predator eggs while bio-dux oil was the least effective oil against the egg stage. Females of N. cucumeris suffered a depression in reproduction when females treated and fed on prey formerly kept on treated plant leaves with LC50 concentration of each oil used in our studies. Rosemary and sweet marjoram as well as bio-dux oils seem to be slightly harmful to N. cucumeris at (LC50) concentration of each oil