In vitro acaricidal effect of Jatropha curcas methanol extract on Rhipicephalus (Boophilus) decoloratus larvae

Abstract

Tick infestation is considered a major problem because ticks cause widespread nuisance and losses and vectors of disease-causing agents, resulting in economic losses in livestock production. The use of chemical agents is the main stay in tick-control though current research into viable plant extracts as alternatives are on the increase. This study evaluated the larvicidal effect of crude methanolic extract of Jatropha curcas seed oil extract on Rhipicephalus (Boophilus) decoloratusticks. Various concentrations of 6.25, 12.5, 25 and 50 mg/ml were prepared from a stock (100 mg/ml) solution of the sample; control using 1% tween 80 and standard acaricide; Amitraz (positive control) were used. The mortalities were observed at time intervals of 6, 12, 18, 24 and 48 hours. The experiment was performed in triplicate. The extract had an LC₅₀ and LC₉₀ of 2.88mg/ml and 6.76mg/ml respectively after 48h. Carbohydrates, cardiac glycosides, saponins, tannins, steroids, terpenes, alkaloids and flavonoids were detected as phytoconstituents, and the extract exhibited significant mean percentage mortality from the control across all the concentrations after 24h. The result confirms that J. curcas is a good alternative to be used as a larvicidal agent in the control of Rhipicephalus (Boophilus) decoloratus.