Title: Effect of gossypolone on the growth and development of helicoverpa zea Authors
|O NEIL, THOMAS|
|Hake, Kater -|
Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: February 10, 2014
Publication Date: March 10, 2014
Citation: Stipanovic, R.D., Esquivel, J.F., Westbrook, J.K., Puckhaber, L.S., O Neil, T.M., Bell, A.A., Duke, S.E., Dowd, M.K., Hake, K.D. 2014. Effect of gossypolone on the growth and development of helicoverpa zea. Proceedings of the Beltwide Cotton Conferences. p. 706. Technical Abstract: The pigment glands of the cotton plant (Gossypium) produce terpenoid aldehydes that protect the plant from herbivorous insects. Of these terpenoids, the most extensively studied is gossypol. Gossypolone, a compound closely related to gossypol, has been reported in these pigment glands but its activity against Helicoverpa zea (Boddie) has not been reported. We now report the effect of gossypol and gossypolone fed to 1st instar of H. zea at concentrations of 0.06%, 0.08% and 0.12% in an artificial diet. In previous studies, gossypol showed a hormetic effect when fed to Heliothis virescens (Fabricius) or Helicoverpa armigera (Hübner); in the present study gossypol also showed a hormetic effect when fed to H. zea. Gossypolone did not exhibit a hormetic effect at the concentrations tested, but pupae from larvae fed 0.12% gossypolone were significantly smaller than those fed the control diet or any of the diets with gossypol. Gossypol at the concentrations tested did not extend days-to-pupation, but in an earlier study gossypol at 0.16% extended days-to-pupation from 13.9 days (± 0.5) to 22.6 days (± 1.0). In this study, gossypolone also extended days-to-pupation but at a lower concentration [i.e., gossypolone at 0.12% extended days-to-pupation from 13.3 days (± 0.1) for the control to 20.8 days (± 0.7)]. A delay in days-to-pupation will reduce the number of generations that develop during a growing season, and may reduce larval survival. Manipulation of the genes responsible for the biosynthesis of gossypolone in cotton plants could provide an overall increase in resistance to Heliothines pests of cotton.