title: In vitro acaricidal activity of Bobgunnia madagascariensis Desv. against Amblyomma variegatum (Fabricius) (Acari: Ixodidae).
abstract: The objective of the study was to determine the acaricidal properties of Bobgunnia madagascariensis (Desv.) J.H. Kirkbr. and Wiersema (Leguminosae) against adult Amblyomma variegatum (Fabricius) ticks, using Tephrosia vogelii Hook.f. (Leguminosae) as a positive control. Plant extracts of both were prepared using methanol, acetone and chloroform as extraction solvents. Methanol leaf extracts of T. vogelii (0.014 g) and methanol fruit extracts of B. madagascariensis (0.0062 g) gave the highest mean extraction weights among the plant parts and solvents used. In free contact bioassays, only methanol extracts of the bark and leaf material of T. vogelii and methanol fruit extracts of B. madagascariensis produced 100 % mortality of A. variegatum ticks in 24 h. The acaricidal activity of methanol leaf extracts of T. vogelii persisted for up to 8 days while that of fruit extracts of B. madagascariensis persisted for only 6 days. In topical application bioassays, the toxicity of T. vogelii and B. madagascariensis extracts was found to be significantly different at 95 % confidence level, with B. madagascariensis extracts (LD50 0.030 w/v) being more toxic than T. vogelii extracts (LD50 0.555 w/v). This study has shown that plant extracts of B. madagascariensis and T. vogelii extracts have significant in vitro acaricidal activity against A. variegatum ticks and can thus be considered as alternatives for tick control. Further research is however required on persistence, safety and the required application rates.
authors.affiliation: Department of Biological Science, University of Zambia, Box 32379, Lusaka, Zambia. jmuyobela@yahoo.com.|Department of Veterinary and Tsetse Control Services, Ministry of Agriculture and Livestock, Box 410110, Kasama, Zambia. jmuyobela@yahoo.com.
authors.forename: Jackson
authors.initials: J
authors.lastname: Muyobela
authors.affiliation: Department of Veterinary and Tsetse Control Services, Ministry of Agriculture and Livestock, Box 410110, Kasama, Zambia.
authors.forename: Philip Obed Yobe
authors.initials: PO
authors.lastname: Nkunika
authors.affiliation: School of Veterinary Medicine, University of Zambia, Box 32379, Lusaka, Zambia.
authors.forename: Enala Tembo
authors.initials: ET
authors.lastname: Mwase
mesh_terms: D056810:Acaricides / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae; D005638:Fruit; D026863:Ixodidae / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D013983:Tick Control
chemical_list: D056810:Acaricides; D010936:Plant Extracts
keywords: Free contact bioassay; Mortality; Plant extracts; Tick control; Topical application bioassay