Evaluation of Bt resistance in Helicoverpa zea (Lepidoptera: Noctuidae) strains using various Bt cotton plant tissues.
Pest Manag Sci
; 78(1): 95-103, 2022 Jan.
Article
em En
| MEDLINE
| ID: mdl-34448529
ABSTRACT
BACKGROUND:
Diet-overlay bioassays suggest that Helicoverpa zea (Lepidoptera Noctuidae) field populations have developed resistance to some of the Bt insecticidal proteins that are constituents of the pyramids expressed in the second and third generation Bt cotton technologies. Unfortunately, these bioassays are not always a reliable indicator for how a seemingly resistant population will perform in an actual cotton field, and thus, leaf tissue bioassays have been suggested as a method to better assess field performance. However, bollworm larvae typically prefer to feed on floral tissue rather than leaf tissue, and an alternative cotton structure type may be more ideal for use in plant tissue-based bioassays. A series of diet-overlay bioassays using Bt proteins and Bt cotton plant tissue were conducted with laboratory susceptible (Bz-SS) and resistant (Cry-RR, resistant to Cry1Ac and Cry2Ab) H. zea strains to determine if plant tissue overlays could detect resistance and which cotton plant structure type would be most ideal for use in bioassays.RESULTS:
Results suggest that diet overlays using lyophilized plant tissue were able to detect resistance. Lyophilized tissue from white flowers was most ideal for use in bioassays, whereas tissue from non-Bt bolls and leaves affected larval health and behavior, confounding assay results.CONCLUSION:
Overlays using white flower tissue could potentially be used to supplement Bt protein overlays and provide an improved assessment of larval performance on Bt cotton technologies. © 2021 Society of Chemical Industry.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Hemolisinas
/
Mariposas
Limite:
Animals
Idioma:
En
Revista:
Pest Manag Sci
Assunto da revista:
TOXICOLOGIA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Estados Unidos