title: Naturally occurring bioactive compounds from four repellent essential oils against Bemisia tabaci whiteflies.
abstract: BACKGROUND
  In tropical countries, netting is an effective sustainable tool for protecting horticultural crops against Lepidoptera, although not against small pests such as Bemisia tabaci, while smaller mesh netting can be used in temperate regions. A solution is to combine a net with a repellent. Previously we identified repellent essential oils: lemongrass (Cymbopogon citratus), cinnamon (Cinnamomum zeylanicum), cumin (Cuminum cyminum) and citronella (Cymbopogon winternarius). The present study was designed to identify the active compounds of these essential oils, characterise their biological activity and examine their potential for coating nets. We investigated the efficiency and toxicity of nets dipped in different solutions. We then studied the repellent effect with an olfactometer and the irritant effect by videotracking.
  
  
  RESULTS
  Geraniol and citronellol were the most promising net coatings owing to their repellent effect. The repellency, irritancy or toxicity varied with the product and concentration, and these features were independent, indicating that the repellent and the irritant/toxic mechanisms were not the same. The combined effects of these different compounds account for the bioactivity of the mixture, suggesting interactions between the compounds.
  
  
  CONCLUSIONS
  This new sustainable strategy for protecting vegetable crops against whiteflies is discussed, in addition to the use of companion plants that could produce such bioactive compounds.
authors: UR Hortsys, Cirad, Campus de Baillarguet, Montferrier, France.
authors: Emilie
authors: http://orcid.org/0000-0001-7755-7585
authors: E
authors: Deletre
authors: UMR MiVEGEC, IRD-CNRS-UM1-UM2, Monferrier, France.
authors: Fabrice
authors: F
authors: Chandre
authors: UR Hortsys, Cirad, Campus de Baillarguet, Montferrier, France.
authors: Barbara
authors: B
authors: Barkman
authors: Institut des Biomolécules Max Mousseron, Faculté de Pharmacie, Montpellier, France.
authors: Chantal
authors: C
authors: Menut
authors: UR Hortsys, Cirad, Campus de Baillarguet, Montferrier, France.|Plant Health Department, ICIPE, Nairobi, Kenya.
authors: Thibaud
authors: T
authors: Martin
mesh_terms: D000818:Animals; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D028527:Cuminum / Q000737:chemistry*; D031743:Cymbopogon / Q000737:chemistry*; D005260:Female; D006430:Hemiptera; D007302:Insect Repellents; D008297:Male; D009822:Oils, Volatile
chemical_list: D007302:Insect Repellents; D009822:Oils, Volatile
keywords: DEET; behaviour; irritation; permethrin; repellence; toxicity