Prototype 3D-printed traps capture Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) directly into preservative for improved detection of "Candidatus Liberibacter solanacearum"

Authors: WENTZ, KATIE - Heritage University; Cooper, William - Rodney; Horton, David; WOHLEB, CARRIE - Washington State University; WATERS, TIM - Washington State University; HALBERT, SUSAN - Florida Department Of Agriculture And Consumer Services; RAMADUGU, CHANDRIKA - University Of California; SNYDER, JAMES - Florida Department Of Agriculture And Consumer Services; KAO, ROBERT - Heritage University

Submitted to: Journal of Entomological Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/3/2019
Publication Date: 4/2/2020
Citation: Wentz, K., Cooper, W.R., Horton, D.R., Wohleb, C., Waters, T., Halbert, S., Ramadugu, C., Snyder, J., Kao, R. 2020. Prototype 3D-printed traps capture Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) directly into preservative for improved detection of "Candidatus Liberibacter solanacearum". Journal of Entomological Science. 55(2):147-155. https://doi.org/10.18474/0749-8004-55.2.147.
DOI: https://doi.org/10.18474/0749-8004-55.2.147

Interpretive Summary: Potato psyllid is a key pest of potato as a vector of the pathogen that causes zebra chip disease. The psyllid is captured and monitored using sticky card traps, and the captured insects are often used for molecular work including pathogen diagnosis, gut content analysis, and population genetics. Psyllids captured on sticky cards are often collected in poor condition, which may interfere with DNA extraction and molecular methods. Researchers with the USDA-ARS in Wapato WA in collaboration with scientists at Heritage University, Washington State University, University of California Riverside, and Florida Department of Agriculture and Consumer Services examined whether a prototype trap that captures insects directly into a preservative provide specimens that are of higher quality for molecular work. They found that the molecular detection of the zebra chip pathogen was improved in specimens recovered from the prototype trap compared with those recovered from sticky cards. These results indicate that capturing psyllids directly in a preservative instead of on sticky card traps will provide higher quality specimens for molecular work and will substantially improve the future research on potato psyllid and other small insects.

Technical Abstract: Potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) is a key pest of potato (Solanum tuberosum L.) and other Solanaceous crops (Solanales: Solanaceae) as a vector of "Candidatus Liberibacter solanacearum" (Lso), the pathogen associated with zebra chip disease of potato. Potato psyllid populations typically are monitored using sticky card traps, and psyllids collected from sticky traps often are subjected to Polymerase Chain Reaction (PCR) to monitor the incidence of Lso within psyllid populations. Psyllids collected from sticky traps are often mangled, desiccated, and coated with sticky residue, which may interfere with detection of Lso by PCR. A recently developed prototype 3D-printed trap that captures insects directly into a preservative (70% ethanol) was previously tested for monitoring psyllid populations. The capture of psyllids directly into a preservative may reduce degradation of DNA or protect specimens from PCR-inhibiting contaminants, thus improving the detection of Lso by PCR. Our goal was to compare detectability of Lso in psyllids captured into preservative (prototype trap) to that in psyllids removed from sticky card traps. Overall, detection rates were higher in psyllids from the prototype trap than from sticky card traps. This improvement in Lso detection appeared to be partly due to the specimens yielding more DNA of higher quality. Results of this study demonstrate that compared with sticky card traps, the use of a trap which captures psyllids directly into preservative provides higher quality specimens for collection of molecular data including pathogen diagnosis, population genetics, and molecular gut content analysis.