Effects of leaf extracts of Protium spruceanum against adult and larval Rhipicephalus microplus

Current perspectives and difficulties in the design of acaricides and repellents from plant-derived compounds for tick control

Ticks and tick-borne diseases have gained increasing attention in recent years due to their impact on public health and significant losses in livestock production. The use of synthetic compounds for tick control is becoming problematic, mainly due to the resistance to commercially available products as well as their toxicity. Therefore, new alternative control methods are required. For this purpose, plant-derived extracts may be considered as effective repellents and/or acaricides. The present literature review focuses on studies evaluating the acaricidal and repellent activity of plant-derived extracts and plant secondary metabolites. We also noted recent advances in protein-ligand-docking simulation to examine the possible toxic effect of natural chemical compounds on ticks. In conclusion, plant-derived repellents/acaricides can be effective against ticks, especially in rural areas and livestock farms.

Novel Pesticidal Efficacy of Araucaria heterophylla and Commiphora molmol Extracts against Camel and Cattle Blood-Sucking Ectoparasites

Botanical insecticides are promising pest control agents. This research investigated the novel pesticidal efficacy of Araucaria heterophylla and Commiphora molmol extracts against four ectoparasites through treated envelopes. Seven days post-treatment (PT) with 25 mg/mL of C. molmol and A. heterophylla, complete mortality of the camel tick, Hyalomma dromedarii and cattle tick, Rhipicephalus (Boophilus) annulatus were reached. Against H. dromedarii, the median lethal concentrations (LC50s) of the methanol extracts were 1.13 and 1.04 mg/mL and those of the hexane extracts were 1.47 and 1.38 mg/mL, respectively. The LC50 values of methanol and hexane extracts against R. annulatus were 1.09 and 1.41 plus 1.55 and 1.08 mg/mL, respectively. Seven days PT with 12.5 mg/mL, extracts completely controlled Haematopinus eurysternus and Hippobosca maculata; LC50 of Ha. eurysternus were 0.56 and 0.62 mg/mL for methanol extracts and 0.55 and 1.00 mg/mL for hexane extracts, respectively, whereas those of Hi. maculata were 0.67 and 0.78 mg/mL for methanol extract and 0.68 and 0.32 mg/mL, respectively, for hexane extracts. C. molmol extracts contained sesquiterpene, fatty acid esters and phenols, whereas those of A. heterophylla possessed monoterpene, sesquiterpene, terpene alcohols, fatty acid, and phenols. Consequently, methanol extracts of C. molmol and A. heterophylla were recommended as ecofriendly pesticides.

Botanical acaricides and repellents in tick control: current status and future directions

Ticks are obligate blood-sucking ectoparasites and notorious as vectors of a great diversity of, in many instances, zoonotic pathogens which can cause considerable damage to animal and human health. The most commonly used approach for the control of ticks is the application of synthetic acaricides. However, the negative impacts of synthetic acaricides on the treated animals and the environment, in addition to its documented role in the development of resistance has led to the search for safer and more environmentally friendly alternative methods without compromising efficacy. An emerging promising approach for the control of ticks which has attracted much attention in recent years is the use of botanicals. Indeed, botanicals have been widely reported to show diverse effects and great potential as tick repellent and control. Although several excellent reviews have previously focused on this topic, studies on the exploration and application of botanicals to control ticks have expanded rapidly. Herein, we provide an update on the current understanding and status of botanical acaricides and repellents in tick control using recently published articles between 2017 and 2019. We also discuss the challenges and future directions in the application of botanicals in tick control, with a view of providing important clues for designing new integrated tick control methods.