title: Laboratory assessment of acaricidal activity of Cymbopogon winterianus, Vitex negundo and Withania somnifera extracts against deltamethrin resistant Hyalomma anatolicum.
abstract: Larval packet test was used for detection of resistance levels against cypermethrin and deltamethrin, the most commonly used synthetic pyrethroids, in the multi-host tick Hyalomma anatolicum collected from district Moga, Punjab (India). Results indicated the presence of level I resistance against deltamethrin (RF = 2.81), whereas the tick isolate was susceptible to cypermethrin (RF = 0.2). The aqueous and ethanolic extracts of leaves of Cymbopogon winterianus, Vitex negundo and Withania somnifera along with roots of Vitex negundo were assessed for their acaricidal activity against the larvae of deltamethrin resistant H. anatolicum. The efficacy was assessed by measuring per cent larval mortality and determination of LC50 values. The various ethanolic extracts produced a concentration dependent increase in larval tick mortality, whereas the aqueous extracts exhibited a much lower mortality. The highest mortality (93.7 ± 0.66 %) was observed at the 5.0 % concentration of ethanolic extract of leaves of C. winterianus and the lowest LC50 value (0.011 %) was recorded for ethanolic extracts of leaves of V. negundo. The results indicated that these plant extracts have potential to be developed as herbal acaricides.
authors.affiliation: Department of Veterinary Parasitology, College of Veterinary Science, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, 141004, India, nirbhayksingh@yahoo.co.in.
authors.forename: Nirbhay Kumar
authors.initials: NK
authors.lastname: Singh
authors.lastname: Jyoti
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Vemu
authors.forename: Abhijit
authors.initials: A
authors.lastname: Nandi
authors.forename: Harkirat
authors.initials: H
authors.lastname: Singh
authors.forename: Rajender
authors.initials: R
authors.lastname: Kumar
authors.forename: V K
authors.initials: VK
authors.lastname: Dumka
mesh_terms: D056810:Acaricides / Q000633:toxicity*; D000818:Animals; D031743:Cymbopogon / Q000737:chemistry*; D004351:Drug Resistance; D026863:Ixodidae / Q000187:drug effects*; D007814:Larva / Q000187:drug effects; D007928:Lethal Dose 50; D009570:Nitriles; D010571:Pest Control / Q000379:methods; D010936:Plant Extracts / Q000302:isolation & purification / Q000633:toxicity*; D011722:Pyrethrins; D020950:Vitex / Q000737:chemistry*; D032341:Withania / Q000737:chemistry*
chemical_list: D056810:Acaricides; D009570:Nitriles; D010936:Plant Extracts; D011722:Pyrethrins; C017180:decamethrin