title: Chemical composition and mosquito larvicidal activities of Salvia essential oils.
abstract: BACKGROUND
  Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. In this context, essential oils have received much attention as potentially useful bioactive compounds against insects. Therefore, our present study aimed to evaluate the efficacy of essential oils from the aerial parts of Salvia elegans Vahl, Salvia dorisiana Standl., Salvia splendens Sello ex J.A. Schult Blue Ribbon, and S. splendens Sello ex J.A. Schult Scarlet Sage Red (Lamiaceae) against the fourth instar larvae of Aedes albopictus Skuse (Diptera: Culicidae).
  
  
  OBJECTIVE
  The mosquito larvicidal activities of the essential oils and chemical composition of four taxa of Salvia are investigated in this article for the first time.
  
  
  METHODS
  Chemical compositions of essential oils obtained from four taxa of Salvia were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-FID, and the effects of essential oils on fourth instar larvae of A. albopictus were investigated.
  
  
  RESULTS
  The main components identified from each Salvia essential oils were as follows: spathulenol (38.73%) and caryophyllene (10.32%) from S. elegans; ledol (45.8%) and 4,4'-[(p-phenylene)diisopropylidene]diphenol (17.38%) from S. dorisiana; β-cubebene (22.9%), and caryophyllene (12.99%) from S. splendens Blue Ribbon; phytol (41.46%) and cyclooctasulfur (24.88%) from S. splendens Scarlet Sage Red. The essential oils of S. elegans and S. splendens Blue Ribbon had excellent inhibitory larvicidal effect against A. albopictus larvae, and their LC(50) values in 24 h were 46.4 ppm (LC(90) = 121.8 ppm) and 59.2 ppm (LC(90) = 133.0 ppm), respectively.
  
  
  CONCLUSIONS
  These findings demonstrate that the essential oils of these Salvia species could be considered as the powerful candidates to bring about useful botanicals so as to prevent the resurgence of mosquito vectors.
authors.affiliation: Cell and Molecular Biology Division, Department of Botany, University of Calicut, Calicut, Kerala, India.
authors.forename: Jija
authors.initials: J
authors.lastname: Mathew
authors.forename: John E
authors.initials: JE
authors.lastname: Thoppil
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D009822:Oils, Volatile / Q000032:analysis* / Q000494:pharmacology*; D027544:Salvia / Q000737:chemistry*
chemical_list: D007306:Insecticides; D009822:Oils, Volatile