Evaluation of Cytochrome P450 Activity in Field Populations of Cydia pomonella (Lepidoptera: Tortricidae) Resistant to Azinphosmethyl, Acetamiprid, and Thiacloprid

CICHÓN, LILIANA; SOLEÑO, JIMENA; ANGUIANO, OLGA LILIANA; GARRIDO, SILVINA ; MONTAGNA, CRISTINA MÓNICA

JOURNAL OF ECONOMIC ENTOMOLOGY

ENTOMOLOGICAL SOC AMER

Lugar: Lanham; Año: 2013 vol. 106 p. 939 - 944

0022-0493

The Rio Negro and Neuquén Valley is the most important apple and pear growing region in Argentina. Cydia pomonella L. (Lepidoptera: Tortricidae), the main fruit-tree pest is being controlled by azinphosmethyl (AzMe), acetamiprid (Acet), and thiacloprid (Thia) among other insecticides. The objective of this study was to evaluate the response of neonate larvae of codling moth to these three insecticides and on the role of cytochrome P450 monooxygenase in their toxicity. All Þeld populations presented signiÞcantly lower mortality to a discriminating concentration (DC) of Acet and AzMe. In addition, 13 of the 14 populations showed signiÞcantly lower mortality to DC of Thia. Most of the Þeld populations (71%) showed signiÞcantly higher 7-ethoxycoumarine O-deethylase activity compared with the laboratory-susceptible strain. While positive signiÞcant correlation (r = 0.59) was found between Thia and AzMe mortalities at the DC level, no signiÞcant correlations were detected between Acet and Thia (r = 0.35) or Acet and AzMe (r = 0.12). However, Acet and Thia mortalities were signiÞcantly correlated to the percentage of individuals exhibiting 7-ethoxycoumarine O-deethylase activity activities higher than the mean upper 95% conÞdence limit of the susceptible strain (r = 0.52 and r = 0.63, respectively).