Magnitude and Allele Frequency of Cry1F Resistance in Field Populations of the Fall Armyworm (Lepidoptera: Noctuidae) in Brazil
| Autor: | João Victor C. Rodrigues, Analiza P. Alves, Nilson Rodrigues-Silva, Raul Narciso C. Guedes, Thadeu Carlos de Souza, Clébson S. Tavares, Oscar F. Santos-Amaya, Eliseu José G. Pereira |
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| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Veterinary medicine Bacillus thuringiensis Spodoptera Zea mays 01 natural sciences Insecticide Resistance Lepidoptera genitalia Bacterial Proteins Gene Frequency parasitic diseases Animals Allele Allele frequency Genetically modified maize Ecology biology Resistance (ecology) fungi General Medicine Plants Genetically Modified biology.organism_classification 010602 entomology Insect Science Noctuidae Brazil 010606 plant biology & botany |
| Zdroj: | Journal of Economic Entomology. 110:1770-1778 |
| ISSN: | 1938-291X 0022-0493 |
| Popis: | Bacillus thuringiensis (Bt) corn producing the Cry1F protein was the first highly efficacious Bt corn deployed against the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in Brazil, but reduced efficacy of this technology against the fall armyworm has been reported in some regions of the country. Here, we surveyed Cry1F resistance allele frequency and susceptibility of eight S. frugiperda populations collected in 2013 from non-Bt fields in different regions of Brazil. In F1 screen experiments, the overall frequency of the Cry1F resistance alleles in Brazilian populations was estimated at 0.24, with 95% credibility interval between 0.18 and 0.25. In concentration-response bioassays, five of the eight populations surveyed exhibited significant resistance levels, which were over 32 times higher than that of the standard susceptible laboratory strain. The estimates of Cry1F resistance allele frequency were positively correlated with those of median effective or lethal concentrations (i.e., EC50 or LC50). These results show that the allelic frequency and the magnitude of Cry1F resistance are high in field populations of S. frugiperda in Brazil, indicating a challenging situation for resistance management. |
| Databáze: | OpenAIRE |
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