Abstract:
Hot water and hydroethanolic (70:30) extracts were prepared from 15 plant species, which
were investigated to discover eco-friendly and less expensive tick control methods as an
alternative to synthetic acaricides. A contact bioassay was used to determine the acaricidal
activity of these extracts against the cattle tick, Rhipicephalus turanicus (Acari: Ixodidae) at a
concentration of 20% (200 mg/mL). The hydroethanolic extracts had better activity than the
hot water extracts against R. turanicus. The hydroethanolic extract from Tabernaemontana
elegans (leaves) had the best mortality (87.0%). This was followed by Calpurnia aurea (stems)
with a mortality of 75.0%, Schkuhria pinnata (whole plant) with a mortality of 67.0% and Aloe
rupestris (leaves) with a mortality of 66.6%. The toxicity of the plant extracts was also
investigated and it was found that most of the hydroethanolic and hot water extracts were
either safe or very safe on human Vero kidney and liver HepG2 cells. From this study, it was
evident that botanicals have the potential to be developed as environmentally benign natural
acaricides against R. turanicus.
