Protein self-marking by emerald ash borer: an evaluation of efficacy and persistence

Authors: GULA, SCOTT - Purdue University; LOPEZ, VANESSA - Us Forest Service (FS); RAY, ANN - Xavier University; Machtley, Scott; Hagler, James; GINZEL, MATTHEW - Purdue University

Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/3/2020
Publication Date: 10/9/2020
Citation: Gula, S.W., Lopez, V.M., Ray, A.M., Machtley, S.A., Hagler, J.R., Ginzel, M.D. 2020. Protein self-marking by emerald ash borer: an evaluation of efficacy and persistence. Entomologia Experimentalis et Applicata. 168:678-687. https://doi.org/10.1111/eea.12941.
DOI: https://doi.org/10.1111/eea.12941

Interpretive Summary: Understanding the dispersal ability of invasive insect pests provides useful insights for developing effective management strategies. Historically, methods for marking insects for dispersal studies have been expensive, time-consuming, and labor-intensive. The protein immunomarking technique (PIT), developed by an ARS scientist at Maricopa, AZ, is a well-established technique for tracking the dispersal of insects, however, it has not been applied to studies of invasive woodborer beetle dispersal behavior. ARS scientists collaborated with scientists at Purdue University to determine if the PIT would be an effective method for tracking the invasive emerald ash borer (EAB). Adult EAB self-marked as they emerged from protein-treated logs, with higher protein concentrations persisting for longer on the cuticle when exposed to sun and rain. This marking method offers a convenient, inexpensive and durable means of marking woodborers and circumvents the need for human handling, allowing for more natural behavior and more realistic estimates of dispersal. Protein self-marking marking may find application in studies of woodborer dispersal within natural forest environments.

Technical Abstract: Understanding the dispersal ability of invasive insects provides useful insights for developing effective management strategies. Historically, methods for marking insects for dispersal studies have been expensive, time-consuming, labor-intensive, and oftentimes ineffective, especially for woodboring beetles. Also, capturing or rearing insects requires human handling, which can alter behavior. Protein immunomarking is a well-established technique for studying the dispersal of insects, however, it has not been applied to woodborers. This study evaluates the potential for using immunoproteins applied directly to woodborer-infested trees to mark emerging beetles. Specifically, in the first experiment, we sprayed varying concentrations of ovalbumin (egg white) solution directly onto logs infested with emerald ash borer (EAB, Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae: Agrilini). In turn, an enzyme linked immunosorbent assay (ELISA) was used to detect the presence of protein on emerged beetles. To test the persistence of the mark, we applied varying concentrations of albumin to freeze-killed beetles, mounted them on pins, and placed them over various time intervals in an exposed location outdoors. Adult EAB self-marked as they emerged from protein-treated trees, with higher protein concentrations persisting for longer on the cuticle when exposed to sun and rain. This technique offers a convenient, inexpensive, and durable means of marking woodborers and circumvents the need for human handling, allowing for more natural behavior and more realistic estimates of dispersal. Protein self-marking marking may find application in studies of woodborer dispersal within natural forest environments.