title: Plant growth regulatory effect and insecticidal activity of the extracts of the Tree of Heaven (Ailanthus altissima L.).
abstract: BACKGROUND
  There is an urgent need to explore and utilize naturally occurring products for combating harmful agricultural and public health pests. Secondary metabolites in the leaves of the Tree of Heaven, Ailanthus altissima L. have been reported to be herbicidal and insecticidal. The mode of action, however, of the active compounds in A. altissima are not understood. In this paper, we report the chemical characteristics of the herbicidal and insecticidal components in this tree, and will discuss the effect of light on the bioactivity of the active components.
  
  
  RESULTS
  Extracts from the fresh leaves of A. altissima showed a strong plant germination/growth inhibitory effect in laboratory bioassays against alfalfa (Medicago sativa). The effect was dose-dependent. The growth inhibitory components were in the methylene chloride soluble fraction of the extract. The effect was greater in the light than in the dark. Other fractions had plant growth enhancing effect at lower concentrations. The extract was slightly insecticidal against yellow fever mosquito larvae (Aedes aegypti).
  
  
  CONCLUSIONS
  The extract or its semi-purified fractions of A. altissima were strong plant growth inhibitors, therefore good candidates as potential environmentally safe and effective agricultural pest management agents. The finding that light affects the activity will be useful in the application of such natural products.
authors.affiliation: Food Research Program, Agriculture & Agri-Food Canada, Ontario NIG 5C9. caor@em.agr.ca
authors.forename: Rong
authors.initials: R
authors.lastname: Tsao
authors.forename: Frieda E
authors.initials: FE
authors.lastname: Romanchuk
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Peterson
authors.forename: Joel R
authors.initials: JR
authors.lastname: Coats
mesh_terms: D000330:Aedes / Q000187:drug effects* / Q000254:growth & development; D032268:Ailanthus / Q000737:chemistry*; D000818:Animals; D004353:Drug Evaluation, Preclinical; D006540:Herbicides / Q000302:isolation & purification / Q000494:pharmacology*; D007306:Insecticides / Q000302:isolation & purification / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D008027:Light; D000455:Medicago sativa / Q000187:drug effects* / Q000254:growth & development; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D006540:Herbicides; D007306:Insecticides; D010936:Plant Extracts