Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2001
Publication Date: September 15, 2001
Citation: Landolt, P.J., Alfaro, J. 2001. Trapping Lacanobia subjuncta, Xestia c-nigrum and Mamestra configurata (Lepidoptera: Noctuidae)with acetic acid and 3-methyl-1-butanol in controlled-release dispensers. Environmental Entomology. 30: 656-662. Interpretive Summary: New approaches and methods are needed to control lepidopterous larvae on agricultural crops without using broad spectrum pesticides. Chemical attractants can be used to determine the best time to use control methods and can be used directly to trap problem insect pests. Scientists at the USDA-ARS Yakima Agricultural Research Laboratory are developing such attractants for use against a number of moth species that are pests of tree fruit and vegetable crops. One such lure that was recently discovered is acetic acid with 3-methyl-1-butanol, which is attractive to several moth pests in the family Noctuidae. A controlled release dispenser was developed for this chemical attractant that provides a constant and optimized amount of the chemicals released for attracting pest moths. Additionally, this dispenser can be used in dry traps which are much easier to use than the wet traps previously tested. These developments make the lure and trap system much easier to use and increase the sensitivity of the system in attracting and trapping moths.
Technical Abstract: Both sexes of the noctuid moths Lacanobia subjuncta (Grote and Robinson), Mamestra configurata Walker (bertha armyworm) and Xestia c-nigrum (L.) (spotted cutworm) are attracted to the combination of acetic acid and 3-methyl-1-butanol (isoamyl alcohol). A controlled-release system for use of this attractant in traps was comprised of separate polypropylene vials for each chemical with the chemical release rate delimited by a hole in the vial lid. When hole sizes for both acetic acid and 3-methyl-1-butanol were varied together, numbers of all three moth species trapped were greatest with vial hole sizes of 1.0 mm diam. For all three species, captures of moths were also positively correlated with the ratio of acetic acid to 3-methyl-1-butanol vial hole sizes (acetic acid hole size was varied, 3-methyl-1-butanol hole size was held constant). Captures of these moths were not correlated with the ratio of 3-methyl-1-butanol to acetic acid hole sizes (3-methyl-1-butanol vial hole size varied, acetic acid vial hole size was held constant), over the range of hole sizes tested. Captures of L. subjuncta, M. configurata, and X. c-nigrum in a wet trap were significantly increased by the addition of boric acid to a drowning solution to retard microbial growth and decomposition of specimens. In a comparison of different designs of traps baited with acetic acid and 3-methyl-1-butanol, greatest numbers of all three species were captured in a dry "bucket" trap which moths entered from the top.