Impact of Spodoptera frugiperda neonate pretreatment conditions on Vip3Aa19 insecticidal protein activity and laboratory bioassay variation
| Autor: | Carolina Camargo Gil, Terence A. Spencer, Frederick S. Walters, Blair D. Siegfried, Karen F. Da Silva |
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| Rok vydání: | 2015 |
| Předmět: |
0106 biological sciences
0301 basic medicine Integrated pest management Male Insecticides Time Factors Photoperiod Introgression Spodoptera 01 natural sciences fall armyworm Toxicology 03 medical and health sciences Bioassay Animals Protein activity Vip3A Research Articles photoperiodism Larva biology fungi Proteins Humidity General Medicine Reference Standards biology.organism_classification 010602 entomology 030104 developmental biology Animals Newborn bioassay Insect Science Fall armyworm Biological Assay Female variation Laboratories Agronomy and Crop Science Research Article |
| Zdroj: | Pest Management Science |
| ISSN: | 1526-4998 |
| Popis: | BACKGROUND Variation in response to insecticidal proteins is common upon repetition of insect bioassays. Understanding this variation is a prerequisite to detecting biologically important differences. We tracked neonate Spodoptera frugiperda (J.E. Smith) susceptibility to Vip3Aa19 over 17 generations using standardized bioassay methods. Five larval pretreatment conditions and one bioassay condition were tested to determine whether susceptibility was affected. These included: storage time; prefeeding; storage at reduced temperature; storage at reduced humidity; colony introgression of field-collected individuals. Extremes of photoperiod during the bioassay itself were also examined. RESULTS LC50 values for two strains of S. frugiperda varied 6.6-fold or 8.8-fold over 17 generations. Storage time and humidity had no impact on Vip3Aa19 susceptibility, whereas prefeeding significantly reduced subsequent mortality (by 27%). Storage at reduced temperature increased mortality for one colony (from 45.6 to 73.0%) but not for the other. Introgression of field-collected individuals affected susceptibility at the first generation but not for subsequent generations. A 24 h bioassay photophase significantly reduced susceptibility (by 26%) for both colonies. CONCLUSION Certain pretreatment and bioassay conditions were identified that can affect S. frugiperda Vip3Aa19 susceptibility, but innate larval heterogeneity was also present. Our observations should help to increase the consistency of insecticidal protein bioassay results. © 2015 Syngenta Crop Protection, LLC. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. |
| Databáze: | OpenAIRE |
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