Evaluation of Essential Oils Derived from (Piperaceae) and (Rutaceae) against the Tick (Acari: Ixodidae).

The present research aimed to study the chemical composition and acaricidal activity of and essential oils against the cattle tick . GC-MS analysis of essential oil showed limonene (50.3%), -pinene (14.4%), and -terpinene (11.7%) as the major components; oil was mainly composed of -caryophyllene (26.2%), -ocymene (5.8%), and -pinene (5.5%). Acaricide activity was evaluated at concentrations of 2.5, 5.0, and 10.0% (v/v) of each plant oil, as well as 1 : 1 combination of both oils (5% : 5%, 2.5% : 2.5%, and 1.25% : 1.25% each), by immersing engorged females for one minute. The LC90 of oils from and the combination were 4.9%, 14.8%, and 5.1%, respectively. essential oil caused 100% mortality of engorged females at the highest concentration (10%). essential oil inhibited egg-laying by up to 96% in a concentration-dependent manner, suggesting it reduces tick fecundity. When combined, the oils presented toxicity as to oil alone, but with stronger inhibition of oviposition (5% : 5%), indicating a possible additive effect against . The present data provide support for further investigation of novel natural products to control bovine tick infestations.