Entomologia Experimentalis et Applicata (2004) 110, 23-30
Gema P. Farinós, Marta de la Poza, Pedro Hernández-Crespo, Félix Ortego and Pedro Castañera (2004)
Resistance monitoring of field populations of the corn borers Sesamia nonagrioides and Ostrinia nubilalis after 5 years of Bt maize cultivation in Spain
Entomologia Experimentalis et Applicata 110 (1), 23-30
Abstract: Approximately 22 000 hectares (5% of the total maize growing area) of transgenic maize expressing the Cry1Ab toxin from Bacillus thuringiensis (Bt maize) have been planted annually in Spain since 1998. Changes in the susceptibility to Cry1Ab of Spanish populations of the Mediterranean corn borer (MCB), Sesamia nonagrioides (Lefebvre) (Lepidoptera: Noctuidae), and the European corn borer (ECB), Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), were assessed by annual monitoring on Bt maize fields. No increase in resistance was detected in the MCB populations from Ebro, Albacete, and Badajoz, nor in the ECB populations from Ebro and Badajoz during the period 1999-2002. The susceptibility of the MCB population from Madrid fluctuated from year to year, but a gradual trend towards higher levels of tolerance was not observed. Laboratory selection assays for eight generations yielded selected strains of MCB and ECB that were 21- and 10-fold significantly more tolerant to Cry1Ab than the corresponding unselected strains, respectively. Nevertheless, none of the field-collected or laboratory-selected larvae were able to survive on Bt maize. Considering these data, no consistent shifts in susceptibility were found for Spanish populations of MCB nor ECB after 5 years of Bt maize cultivation, but systematic field monitoring needs to be continued.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Pedro Castañera, Félix Ortego
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
resistance/tolerance/defence of host
Research topic(s) for beneficials or antagonists:
resistance/tolerance/defence of host
