Behavioral and Electrophysiological Responses of Leafroller Moths to Selected Plant Extracts

The behavioral and electrophysiological responses of the obliquebanded leafroller, Choristoneura rosaceana (Harris), and the redbanded leafroller, Argyrotaenia velutinana (Walker), to crude extracts of Arctium lappa, Bifora radians, Humulus lupulus, Xanthium strumarium, and Verbascum spp. were studied under laboratory conditions. Plant materials were dried and ground before extraction with methanol. Plant extract residues were mixed in acetone to give 20% (wt:wt) suspensions after evaporation of excess methanol. All Þve plant extracts elicited signiÞcant electroantennogram (EAG) responses from both males and females of each species. EAG responses to X. strumariumwere generally the highest for both species. The behavioral responses of male and female obliquebanded leafrollers to the plant extracts were comparedwith responses to pheromone [(Z)11Ð 14:Ac] and a solvent control. SigniÞcantly more male and female obliquebanded leafrollers were attracted toX. strumarium comparedwith pheromone on Þlter paper,H. lupulus,Verbascum spp., and the control. Compared with the control, there was no signiÞcant attraction to pheromone on Þlter paper, A. lappa, H. lupulus, and Verbascum spp. The oviposition-deterring effect of plant extracts on female obliquebanded leafrollers was studied in dual-choice bioassays. B. radians elicited the highest ovipositiondeterring effectwithno eggs laid on this treatment.A. lappawas also effective and reduced oviposition to 2.9% of that observed in the controls. The number of eggs laid onX. strumarium (14.4%) and Verbascum spp. (21.2%) treatments were not signiÞcantly reduced relative to the control; however, ovipositionwas reducedby three-fold by these two treatments. The results show that certain crude plant extracts induce behavioral effects on male and female obliquebanded leafrollers. Further studies are needed to determine the active ingredients and their potential use in pest management strategies aimed at managing these pest species in tree fruit production.