title: Mechanism of leaf-cutting ant colony suppression by fipronil used in attractive toxic baits.
abstract: BACKGROUND
  Attractive toxic baits are the prevailing method for managing leaf-cutting ants in the eucalypt forests planted for the production of pulp, paper, timber and charcoal. For successful use in these baits, the insecticidal compounds need to circumvent the typical defences of the eusocial leaf-cutting ants. The challenge is to have an insecticide in the bait that will not directly harm and/or compromise foraging workers, but that will eventually suppress the colony. These underlying mechanisms are poorly known, and here the potential mechanism of fipronil activity in toxic baits for leaf-cutting ants was assessed using colonies of the representative Neotropical Acromyrmex subterraneus subterraneus (Forel, 1893).
  
  
  RESULTS
  Although forager activity was not directly impaired by fipronil, the insecticide affected forager nestmate interactions (auto- and allogrooming) and waste removal and, more importantly, greatly affected the minor workers, impairing their activities of fungus garden cultivation and progeny handling. The fast decay of the fungus garden compromised the sustainability of the colonies, ultimately leading to their demise within 8 days.
  
  
  CONCLUSIONS
  The behavioural effects of sublethal insecticide exposure towards minor workers are the main determinants of insecticide activity as ant baits and should be targeted in developing such compounds. © 2016 Society of Chemical Industry.
authors.affiliation: Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Lailla C
authors.initials: LC
authors.lastname: Gandra
authors.affiliation: Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Karina D
authors.initials: KD
authors.lastname: Amaral
authors.affiliation: Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Joel C
authors.initials: JC
authors.lastname: Couceiro
authors.affiliation: Departamento de Biologia Animal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Terezinha Mc
authors.initials: TM
authors.lastname: Della Lucia
authors.affiliation: Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Raul Nc
authors.initials: RN
authors.lastname: Guedes
mesh_terms: D000818:Animals; D001000:Ants / Q000187:drug effects*; D001522:Behavior, Animal / Q000187:drug effects; D005260:Female; D005298:Fertility / Q000187:drug effects; D005658:Fungi / Q000254:growth & development; D007306:Insecticides / Q000494:pharmacology*; D011720:Pyrazoles / Q000494:pharmacology*; D012919:Social Behavior
chemical_list: D007306:Insecticides; D011720:Pyrazoles; C082360:fipronil
keywords: ant control; behavioural activity; colony suppression; insecticide activity; insecticide-induced impairment; leaf-cutting ant management