title: Evaluation of DEET and eight essential oils for repellency against nymphs of the lone star tick, Amblyomma americanum (Acari: Ixodidae).
abstract: DEET and Eight commercially available essential oils (oregano, clove, thyme, vetiver, sandalwood, cinnamon, cedarwood, and peppermint) were evaluated for repellency against host-seeking nymphs of the lone star tick, Amblyomma americanum. Concentration-repellency response was established using the vertical paper bioassay technique for each essential oil and compared with that of N,N-diethyl-3-methyl benzamide (DEET), a standard repellent compound present in many commercial repellent formulations. The effective concentration of DEET that repels 50% of ticks (EC50) was estimated at 0.02 mg/cm(2), while EC50s of the essential oils fall between 0.113 and 0.297 mg/cm(2). Based on EC50 estimates, oregano essential oil was the most effective among all essential oils tested, followed by clove, thyme, vetiver, sandalwood, cinnamon, cedarwood, and peppermint oils. None of the tested essential oils demonstrated a level of tick repellency found with DEET. Results from this study illustrated the challenge in search for more effective natural tick repellents.
authors.affiliation: USDA, ARS, Invasive Insect Biocontrol and Behavior Laboratory, 10300 Baltimore Avenue, Beltsville, MD, 20705, USA.|College of Life Sciences, Hebei Normal University, No 20, Road E. 2nd Ring South, Shijiazhuang, 050024, Hebei, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Meng
authors.affiliation: USDA, ARS, Invasive Insect Biocontrol and Behavior Laboratory, 10300 Baltimore Avenue, Beltsville, MD, 20705, USA. Andrew.Li@ars.usda.gov.
authors.forename: Andrew Y
authors.initials: AY
authors.lastname: Li
authors.affiliation: Biological and Health Science Center, Federal University of Maranhão, Av. dos portugueses, 1966, Cidade Universitária do Bacanga, São Luís, MA, CEP 65080-805, Brazil.
authors.forename: Livio M
authors.initials: LM
authors.lastname: Costa Junior
authors.affiliation: Department of Biology, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Castro-Arellano
authors.affiliation: College of Life Sciences, Hebei Normal University, No 20, Road E. 2nd Ring South, Shijiazhuang, 050024, Hebei, China.
authors.forename: Jingze
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D003671:DEET; D007302:Insect Repellents; D026863:Ixodidae; D009758:Nymph; D009822:Oils, Volatile
chemical_list: D007302:Insect Repellents; D009822:Oils, Volatile; D003671:DEET
keywords: Amblyomma americanum; Essential oil; Lone star tick; Repellent