title: Larvicidal efficacies and chemical composition of essential oils of Pinus sylvestris and Syzygium aromaticum against mosquitoes.
abstract: OBJECTIVE
  To assess the chemical composition and mosquito larvicidal potentials of essential oils of locally sourced Pinus sylvestris (P. sylvestris) and Syzygium aromaticum (S. aromaticum) against Aedes aegypti (A. aegypti) and Culex quinquefasciatus (C. quinquefasciatus).
  
  
  METHODS
  The chemical composition of the essential oils of both plants was determined using GC-MS while the larvicidal bioassay was carried out using different concentrations of the oils against the larvae of A. aegypti and C. quinquefasciatus in accordance with the standard protocol.
  
  
  RESULTS
  The results as determined by GC-MS showed that oil of S. aromaticum has eugenol (80.5%) as its principal constituent while P. sylvestris has 3-Cyclohexene-1-methanol, .alpha., .alpha.4-trimethyl (27.1%) as its dominant constituent. Both oils achieved over 85% larval mortality within 24 h. The larvae of A. aegypti were more susceptible to the oils [LC50 (S. aromaticum)=92.56 mg/L, LC50(P. sylvestris)=100.39 mg/L] than C. quinquefasciatus [LC50(S. aromaticum)=124.42 mg/L; LC50(P. sylvestris)=128.00 mg/L]. S. aromaticum oil was more toxic to the mosquito larvae than oil of P. sylvestris but the difference in lethal concentrations was insignificant (P>0.05).
  
  
  CONCLUSIONS
  The results justify the larvicidal potentials of both essential oils and the need to incorporate them in vector management and control.
authors.affiliation: Department of Chemical Sciences, Osun State University, Osogbo, Nigeria.
authors.forename: Kehinde Adenike
authors.initials: KA
authors.lastname: Fayemiwo
authors.forename: Monsuru Adebayo
authors.initials: MA
authors.lastname: Adeleke
authors.forename: Ovie Princewill
authors.initials: OP
authors.lastname: Okoro
authors.forename: Shola Hezekiah
authors.initials: SH
authors.lastname: Awojide
authors.forename: Ilias Olufemi
authors.initials: IO
authors.lastname: Awoniyi
mesh_terms: D000818:Animals; D009033:Culicidae / Q000187:drug effects*; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects*; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D041605:Pinus sylvestris / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D027842:Syzygium / Q000737:chemistry*
chemical_list: D007306:Insecticides; D009822:Oils, Volatile; D010936:Plant Extracts
keywords: Chemical analysis; Essential oils; Larvicides; Mosquitoes; Pinus sylvestris; Syzygium aromaticum