Submitted to: Journal of Entomological Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2011
Publication Date: 10/1/2011
Citation: Allen, K.C., Luttrell, R.G. 2011. Temporal and spatial distribution of Helicoverpa zea and Heliothis virescens (Lepidoptera: noctuidae) moths in pheromone traps across agricultural landscapes in Arkansas. Journal of Entomological Science. 46(4):269-283.
Interpretive Summary: An understanding of the distribution of insect pests across the landscape is important for implementing proactive control measures and in developing plans to alleviate insect resistance to insecticides. The influence of cropping patterns may have profound effects on numbers and timing of insect pests within a defined area. Traps baited with lures for the attraction of male moths have been useful and convenient tools in examining numbers of a particular pest insect at a defined point within the landscape for an extended time period. Coupling moth trap captures with information about the crops grown adjacent to and surrounding the moth traps provides information about the importance of these different crops to insect populations at different time periods during the growing season. The caterpillars of the tobacco budworm and bollworm are pests of numerous crops grown in the U. S. and their populations as measured in moth traps in relation to different crop hosts within Arkansas was measured over a three-year period. Overall, fewer tobacco budworm moths were captured than bollworm moths. More tobacco budworm moths were captured next to early-planted soybean fields and cotton fields planted with varieties that were not genetically modified to express an insecticide (non-Bt cotton) than in traps next to corn and cotton that were genetically modified to express an insecticidal toxin (Bt crops). More bollworm moths were captured in traps located next to corn during the month of June than most other crop types. Fewer bollworm moths were captured during the month of June and more tobacco budworm moths were captured during the month of August in an area of intense cotton production in AR when compared to more diverse cropping environments.
Technical Abstract: Pheromone trap captures of Helicoverpa zea (Boddie) and Heliothis virescens (F.) from 2002-2005 were used to examine the distribution of these species across a multiple crop environment in southeast Arkansas. The greatest number of H. virescens moths was collected during 2003, but densities were low compared with H. zea throughout the study. Overall, fewer H. virescens moths were captured next to Bt corn and Bt cotton than next to non-Bt cotton and early maturing soybean. A significant relationship was not detected between pheromone trap captures of H. virescens and the percentage of these moths that fed on cotton as larvae. More H. zea moths were captured in traps located next to Bt corn and non-Bt corn during the month of June than in traps located next to cotton, sorghum, or soybean, while traps located adjacent to early- and late-maturing varieties of soybean, Bt cotton, non-Bt cotton, and grain sorghum captured greater numbers of moths than those traps located next to corn during July. Therefore, the distribution of H. zea appeared to be influenced by corn acreage during the month of June. Later in the season, this species was widely distributed across the agricultural landscape. Compared to two other regions of AR, fewer H. zea moths were captured during the month of June and more H. virescens moths were captured during August in Mississippi County, an area of intense cotton production.