Two strains of Cydia pomonella (L.) (Lepidoptera: Tortricidae) were selected in the lab by exposure to increasing concentrations of diflubenzuron (Rdfb strain) or azinphos-methyl (Raz strain). Insecticide bioassays showed that the adults of the Rdfb strain exhibited a 2.6-fold and a 7.7-fold resistance ratio to azinphos-methyl and carbaryl, respectively compared to a susceptible strain (S) whereas the adults of the Raz strain exhibited a 6.7-fold resistance ratio to azinphos-methyl and a 130-fold resistance ratio to carbaryl. In the Raz strain, a target site resistance mechanism was suggested by the inhibition of acetylcholinesterase (AChE) activity. In fact the ki values did not discriminate the S and Rdfb strains, while the Raz strain exhibited a 1.7-fold and a 14-fold increase in ki value compared to the S strain for azinphos-methyl oxon and carbaryl, respectively. To verify this hypothesis, two cloned AChE cDNAs sequences (named cydpom-ace2 e cydpom-ace1) were compared between the susceptible and the resistant strains. No difference in the deduced amino acid sequence was found in cydpom-ace2 (orthologous to the Drosophila melanogaster AChE). In the putative eydpom-ace1 (paralogous to the Drosophila AChE), a single amino acid substitution F399V was exclusively present in the Raz strain. The F399 lined the active site of the enzyme and the F399V substitution likely could influence the accessibility of different types of inhibitors to the catalytic site of the insensitive cydpom-ace1. (c) 2006 Elsevier Ltd. All rights reserved.

Acetylcholinesterase mutation in an insecticide-resistant population of the codling moth Cydia pomonella (L.) / Cassanelli, Stefano; M., Reyes; M., Rault; Manicardi, Gian Carlo; B., Sauphanor. - In: INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY. - ISSN 0965-1748. - ELETTRONICO. - 36:8(2006), pp. 642-653. [10.1016/j.ibmb.2006.05.007]

Acetylcholinesterase mutation in an insecticide-resistant population of the codling moth Cydia pomonella (L.)

CASSANELLI, Stefano;MANICARDI, Gian Carlo;
2006

Abstract

Two strains of Cydia pomonella (L.) (Lepidoptera: Tortricidae) were selected in the lab by exposure to increasing concentrations of diflubenzuron (Rdfb strain) or azinphos-methyl (Raz strain). Insecticide bioassays showed that the adults of the Rdfb strain exhibited a 2.6-fold and a 7.7-fold resistance ratio to azinphos-methyl and carbaryl, respectively compared to a susceptible strain (S) whereas the adults of the Raz strain exhibited a 6.7-fold resistance ratio to azinphos-methyl and a 130-fold resistance ratio to carbaryl. In the Raz strain, a target site resistance mechanism was suggested by the inhibition of acetylcholinesterase (AChE) activity. In fact the ki values did not discriminate the S and Rdfb strains, while the Raz strain exhibited a 1.7-fold and a 14-fold increase in ki value compared to the S strain for azinphos-methyl oxon and carbaryl, respectively. To verify this hypothesis, two cloned AChE cDNAs sequences (named cydpom-ace2 e cydpom-ace1) were compared between the susceptible and the resistant strains. No difference in the deduced amino acid sequence was found in cydpom-ace2 (orthologous to the Drosophila melanogaster AChE). In the putative eydpom-ace1 (paralogous to the Drosophila AChE), a single amino acid substitution F399V was exclusively present in the Raz strain. The F399 lined the active site of the enzyme and the F399V substitution likely could influence the accessibility of different types of inhibitors to the catalytic site of the insensitive cydpom-ace1. (c) 2006 Elsevier Ltd. All rights reserved.
2006
36
8
642
653
Acetylcholinesterase mutation in an insecticide-resistant population of the codling moth Cydia pomonella (L.) / Cassanelli, Stefano; M., Reyes; M., Rault; Manicardi, Gian Carlo; B., Sauphanor. - In: INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY. - ISSN 0965-1748. - ELETTRONICO. - 36:8(2006), pp. 642-653. [10.1016/j.ibmb.2006.05.007]
Cassanelli, Stefano; M., Reyes; M., Rault; Manicardi, Gian Carlo; B., Sauphanor
File in questo prodotto:
File Dimensione Formato  
Cassanelli2006.pdf

Solo gestori archivio

Tipologia: Versione pubblicata dall'editore
Dimensione 515.27 kB
Formato Adobe PDF
515.27 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

Licenza Creative Commons
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11380/303954
Citazioni
  • ???jsp.display-item.citation.pmc??? 17
  • Scopus 82
  • ???jsp.display-item.citation.isi??? 79
social impact