Host and non-host whistle stops by psyllids: Molecular gut content analysis by high-throughput sequencing reveals landscape-level movements by Psylloidea (Hemiptera)

Authors: Cooper, William - Rodney; Horton, David; WILDUNG, MARK - Washington State University; JENSEN, ANDY - Washington State Potato Foundation; THINAKARAN, JENITA - University Of California, Davis; RENDON, DALILA - Oregon State University; NOTTINGHAM, LOUIS - Washington State University; BEERS, ELIZABETH - Washington State University; WOHLEB, CARRIE - Washington State University; Hall, David; STELINSKI, LUKASZ - University Of Florida

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/25/2019
Publication Date: 6/7/2019
Publication URL: http://handle.nal.usda.gov/10113/6472487
Citation: Cooper, W.R., Horton, D.R., Wildung, M., Jensen, A., Thinakaran, J., Rendon, D., Nottingham, L., Beers, E., Wohleb, C., Hall, D.G., Stelinski, L. 2019. Host and non-host whistle stops by psyllids: Molecular gut content analysis by high-throughput sequencing reveals landscape-level movements by Psylloidea (Hemiptera). Environmental Entomology. 48(3):554-566. https://doi.org/10.1093/ee/nvz038.
DOI: https://doi.org/10.1093/ee/nvz038

Interpretive Summary: Studying the landscape-level movements of psyllids has proven challenging largely because of limitations in the use of existing methods on a small yet highly mobile insect that occurs on a large diversity of plant species. New methods are therefore needed to study the landscape ecology of psyllid pests. Researchers at the USDA Agricultural Research Service laboratory in Wapato, WA have recently demonstrated that prior landscape-level movements of psyllids, including pear psylla and potato psyllid, can be inferred by identifying what plants the psyllids previously fed upon. This method provides researchers way to identify which weeds serve as sources of psyllid pests that colonize crops and orchards.

Technical Abstract: Psyllids (Hemiptera: Psylloidea) are phloem-feeding insects that tend to be highly specific in their host plants. Some species are well-known agricultural pests, often as vectors of plant pathogens. Many pest psyllids colonize agricultural fields from non-crop reproductive hosts or from non-host transitory and winter shelter plants. Uncertainty about which non-crop species serve as sources of psyllids hinders efforts to predict which fields or orchards are at greater risk of being colonized by psyllids. High-throughput sequencing of trnL, trnF, and ITS was used to examine the dietary histories of three pest and two non-pest psyllid species encompassing a diversity of lifecycles: Cacopsylla pyricola (Förster) (Psyllidae), Bactericera cockerelli (Šulc) (Triozidae), Diaphorina citri Kuwayama (Liviidae), Aphalara loca Caldwell (Aphalaridae), and a Cacopsylla species complex associated with Salix (Malphighiales: Salicaceae). Results revealed an unexpectedly high level of feeding on non-host species by all five psyllid species. The identification of the dietary history of the psyllids allowed us to infer their landscape-scale movements prior to capture. Our study demonstrates a novel use for gut content analysis – to provide insight into landscape-scale movements of psyllids – thus providing a means to pinpoint the non-crop sources of pest psyllids colonizing agricultural crops. We observed previously unknown psyllid behaviors during our efforts to develop this method and discuss new research directions on the future study of psyllid ecology.