title: In vitro evaluation of acaricidal activity of novel green silver nanoparticles against deltamethrin resistance Rhipicephalus (Boophilus) microplus.
abstract: An investigation was undertaken to study, for the first time, in vitro acaricidal activity of green silver nanoparticles on deltamethrin resistance Rhipicephalus (Boophilus) microplus. The compounds tested were neem coated silver nanoparticles (N-Ag NPs), deltamethrin neem coated silver nanoparticles (DN-Ag NPs), 2, 3 dehydrosalannol (2,3 DHS), 2, 3 DHS coated silver nanoparticles (2, 3-DHS-Ag NPs), Quercetin dihydrate (QDH) and QDH coated silver nanoparticles (QDH-Ag NPs). Also included in this study, for the purpose of comparison, were neem leaf extract (NLE), silver nitrate (AgNO3) and deltamethrin (D). Acaricidal activity on larvae and adults of R. (B.) microplus was tested by larval packet test (LPT) and adult immersion test (AIT) respectively. In the LPT, 100% mortality was obtained at concentrations (ppm) of 360, 6000, 260, 200, 50, 300, 85, 600 and 200 for the compounds, D, NLE, Ag NO3, N-Ag NPs, DN-Ag NPs, 2, 3 DHS, 2, 3 DHS-Ag NPs, QDH, QDH-Ag NPs respectively. In AIT, the proportions of mortality and oviposition inhibition were proportionate but the reproductive index was inversely proportional to the concentration of the compounds used. The effect of DN-Ag NPs on mortality was the highest (93.33%) at 50ppm concentration. The mean reproductive index (0.01) and oviposition inhibition (99.16%) values were statistically significant when compared to control group. DN-Ag NPs showed significantly (P<0.05) lower LC50(3.87ppm; 21.95ppm) and LC99(53.05ppm; 90.06ppm) values against both the larvae and adults of R. (B.) microplus. The oviposition inhibiting ability of various compounds was determined to assess the reproductive performance of adult female ticks. The DN-Ag NPs had potent oviposition inhibitory activity with significantly lower IC50and IC99values compared to the rest of the treatments at 0.034 and 51.07ppm respectively. These results showed that the DN-Ag NPs had significant acaricidal activity against R. (B.) microplus.
authors.affiliation: Department of Veterinary Parasitology, College of Veterinary Science, S.V. Veterinary University, Tirupati 517502, A.P., India.
authors.forename: B
authors.initials: B
authors.lastname: Avinash
authors.affiliation: Department of Veterinary Parasitology, College of Veterinary Science, S.V. Veterinary University, Tirupati 517502, A.P., India. Electronic address: venuparas2001@yahoo.com.
authors.forename: R
authors.initials: R
authors.lastname: Venu
authors.affiliation: Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science, S.V. Veterinary University, Proddatur 516360, A.P., India.
authors.forename: M
authors.initials: M
authors.lastname: Alpha Raj
authors.affiliation: Department of Veterinary Parasitology, College of Veterinary Science, S.V. Veterinary University, Tirupati 517502, A.P., India.
authors.forename: K
authors.initials: K
authors.lastname: Srinivasa Rao
authors.affiliation: Department of Veterinary Parasitology, College of Veterinary Science, S.V. Veterinary University, Tirupati 517502, A.P., India.
authors.forename: Ch
authors.initials: C
authors.lastname: Srilatha
authors.affiliation: Nanotechnology Laboratory, Acharya N.G. Ranga Agricultural University, Regional Agricultural Research Station, Tirupati 517502, A.P. India.
authors.forename: T N V K V
authors.initials: TN
authors.lastname: Prasad
mesh_terms: D056810:Acaricides / Q000494:pharmacology*; D000818:Animals; D031601:Azadirachta / Q000737:chemistry*; D005260:Female; D007814:Larva / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry; D009570:Nitriles / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D011722:Pyrethrins / Q000494:pharmacology*; D048494:Rhipicephalus / Q000187:drug effects*; D012834:Silver / Q000494:pharmacology*
chemical_list: D056810:Acaricides; D009570:Nitriles; D010936:Plant Extracts; D011722:Pyrethrins; C017180:decamethrin; D012834:Silver
keywords: Acaricidal activity; Deltamethrin; Green silver nanoparticles; Neem, 2, 3 DHS; QDH; Rhipicephalus (Boophilus) microplus