Skip to main content
ARS Home » Southeast Area » Tifton, Georgia » Crop Protection and Management Research » Research » Publications at this Location » Publication #139826
Title: INFLUENCE OF HERBIVORE-DAMAGED CORN AND COTTON IN THE FIELD RECRUITMENT OF BRACONID PARASITOIDS FROM FERAL POPULATIONS

Author
item Carpenter, James
item Jewett, Darryl

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2003
Publication Date: 9/1/2003
Citation: Carpenter, J.E., Jewett, D.K. 2003. Influence of herbivore-damaged corn and cotton in the field recruitment of braconid parasitoids from feral populations. Florida Entomologist. 86(3):233-238.

Interpretive Summary: Corn and cotton plants that have been attacked by armyworms increase their production and release of specific volatile compounds. In laboratory studies, certain parasitoids of the fall armyworm and the beet armyworm such as Cotesia marginiventris have demonstrated attractiveness to these volatiles. Researchers have suggested that parasitoids may use the release of these volatiles as a way to improve their ability to find and attack the armyworms. We conducted field experiments to investigate the potential of armyworm-damaged plants to influence the rate of parasitism of feral Cotesia marginiventris in corn or cotton plots. In these field studies, we found no evidence that volatiles from corn or cotton induced by armyworm feeding were used by feral parasitoids to improve foraging and parasitism of armyworms.

Technical Abstract: The potential to increase performance of Cotesia marginiventris females by plants as a function of plant interaction with armyworm herbivory was investigated in corn and cotton field plots. The influence of herbivore-damaged corn and cotton plants in the recruitment of feral C. marginiventris adult females was measured by increased parasitism. Spodoptera frugiperda larvae placed in the field plots and then recollected experienced a mean rate of parasitism of approximately 4-6%. Mean total mortality of the collected larvae ranged from 13 to 20%. We found no significant difference in the level of parasitism, or larval mortality between field plots containing herbivore-damaged plants and plants that were undamaged. Under the conditions of this study, we found no evidence that systemic host plant volitiles induced by herbivore feeding were used by feral C. marginiventris to improve foraging and parasitism within a field of corn or cotton.