title: Laboratory evaluation of the effects of Manilkara subsericea (Mart.) Dubard extracts and triterpenes on the development of Dysdercus peruvianus and Oncopeltus fasciatus.
abstract: BACKGROUND
  Studies were carried out to evaluate the effects of Manilkara subsericea extracts and triterpenes on the development of two species of agricultural pest insects, Oncopelus fasciatus and Dysdercus peruvianus.
  
  
  RESULTS
  All treatments of insects with M. subsericea extracts induced mortality, delayed development and inhibited moulting. Some extracts assayed (FH, FB and FD in D. peruvianus, and FH, FB and FEA in O. fasciatus) also produced body deformities in the few adults that emerged. Other extracts (FH, FEA, FB, FD and LET in both insects), however, induced either permanent (overaged) or extranumerary nymphs, both of which were unable to achieve the adult stage and reproductive status. The insects were also treated with triterpenes (α- and β-amyrin acetates) which showed high lethality at 30 days after treatment and delayed the intermoult period so that overaged nymphs were detected.
  
  
  CONCLUSIONS
  The results indicate that extracts and triterpenes from Manilkara subsericea act as potent growth inhibitors of phytophagous hemipteran nymphs. It is also concluded that the mixture of several different molecules in the extracts used produces synergic effects that do not occur after using the triterpenes (PFT) alone. These secondary metabolites in the M. subsericea extracts can potentially be used in integrated control programmes against crop pests.
authors.affiliation: Laboratórios de Tecnologia de Produtos Naturais, Faculdade de Farmácia, Universidade Federal Fluminense, Niterói, RJ, Brazil.
authors.forename: Caio P
authors.initials: CP
authors.lastname: Fernandes
authors.forename: Alexandre
authors.initials: A
authors.lastname: Xavier
authors.forename: João Pedro Furtado
authors.initials: JP
authors.lastname: Pacheco
authors.forename: Marcelo Guerra
authors.initials: MG
authors.lastname: Santos
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Mexas
authors.forename: Norman A
authors.initials: NA
authors.lastname: Ratcliffe
authors.forename: Marcelo Salabert
authors.initials: MS
authors.lastname: Gonzalez
authors.forename: Cícero Brasileiro
authors.initials: CB
authors.lastname: Mello
authors.forename: Leandro
authors.initials: L
authors.lastname: Rocha
authors.forename: Denise
authors.initials: D
authors.lastname: Feder
mesh_terms: D000818:Animals; D020062:Heteroptera / Q000187:drug effects* / Q000254:growth & development*; D007306:Insecticides / Q000494:pharmacology*; D032129:Manilkara / Q000737:chemistry*; D018978:Molting / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D007306:Insecticides; D010936:Plant Extracts; D014315:Triterpenes