In vitro evaluation of acaricidal activity of different plant extracts against Rhipicephalus (Boophilus) microplus

Ticks and tick born diseases affect the economics of dairy and farm animals. Continuous use of acaricides leads to development of acaricide resistance in the tick population, in order to overcome resistance, newer alternatives like herbal extracts can be used as acaricides. The following study is designed to evaluate the acaricidal efficacy of Azadirachta indica, Calotropis gigantea and Ricinus communis against R. (Boophilus) microplus tick. Aqueous plant extracts were prepared from dried plant material and these were evaluated using two different bioassays like adult immersion test and larval packet test. At 80 mg/ml concentration A. indica showed lowest LC 50 and LC 99 values when compared to R. communis and C. gigantea. In conclusion A. indica is relatively more efficient in acaricidal activity than R. communis followed by C. gigantea .