title: Determination of baseline susceptibility of European populations of Tuta absoluta (Meyrick) to indoxacarb and chlorantraniliprole using a novel dip bioassay method.
abstract: BACKGROUND
  Tuta absoluta(Meyrick) is one of the most serious pests of tomato recently introduced in the Mediterranean region. A novel bioassay method designed for the accurate determination of insecticide toxicity on T. absoluta (IRAC method No. 022) was validated by three different laboratories [Greece (NAGREF), Italy (UC) and Spain (UPCT)] on European populations.
  
  
  RESULTS
  The insecticides indoxacarb and chlorantraniliprole were used as reference products. The IRAC leaf dip method is easy to perform, producing repeatable, homogeneous responses. LC(50) values for indoxacarb ranged between 1.8 and 17.9 mg L(-1) (NAGREF), 0.93 and 10.8 mg L(-1) (UC) and 0.20 and 0.70 mg L(-1) (UPCT), resulting in a tenfold, 12-fold and fourfold difference between the least and most susceptible populations at each laboratory respectively. For chlorantraniliprole, LC(50) values ranged between 0.10 and 0.56 mg L(-1) (NAGREF), 0.23 and 1.34 mg L(-1) (UC) and 0.04 and 0.24 mg L(-1) (UPCT), resulting in a sixfold difference in all three cases. Overall, UPCT reported lower mean LC(50) to indoxacarb, while UC reported higher LC(50) to chlorantraniliprole.
  
  
  CONCLUSIONS
  The new bioassay is reliable, providing a useful tool in the design of IRM strategies. Within each country/lab, the variability observed in the results for both indoxacarb and chlorantraniliprole can be attributed to natural variation. Future research is necessary to determine the extent to which it is possible to compare results among laboratories.
authors.affiliation: National Agricultural Research Foundation (NAGREF), Plant Protection Institute of Heraklion, Heraklion, Greece. eroditakis@gmail.com
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Roditakis
authors.forename: Christina
authors.initials: C
authors.lastname: Skarmoutsou
authors.forename: Marianna
authors.initials: M
authors.lastname: Staurakaki
authors.forename: María del Rosario
authors.initials: Mdel R
authors.lastname: Martínez-Aguirre
authors.forename: Lidia
authors.initials: L
authors.lastname: García-Vidal
authors.forename: Pablo
authors.initials: P
authors.lastname: Bielza
authors.forename: Khalid
authors.initials: K
authors.lastname: Haddi
authors.forename: Carmelo
authors.initials: C
authors.lastname: Rapisarda
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Rison
authors.forename: Andrea
authors.initials: A
authors.lastname: Bassi
authors.forename: Luis A
authors.initials: LA
authors.lastname: Teixeira
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods*; D007306:Insecticides / Q000494:pharmacology*; D007928:Lethal Dose 50; D009036:Moths / Q000187:drug effects*; D010078:Oxazines / Q000494:pharmacology*; D062367:ortho-Aminobenzoates / Q000494:pharmacology*
chemical_list: D007306:Insecticides; D010078:Oxazines; D062367:ortho-Aminobenzoates; C401104:indoxacarb; C517733:chlorantranilipole