Stylet probing behavior of two Bactericera (Hemiptera:Psylloidea:Triozidae) species on host and nonhost plants

Authors: MUSTAFA, TARIQ - Washington State University; Horton, David; Cooper, William - Rodney; ZACK, RICH - Washington State University; THINAKARAN, JENITA - University Of Idaho; KARASEV, ALEXANDER - University Of Idaho; Munyaneza, Joseph - Joe

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/12/2021
Publication Date: 4/12/2021
Citation: Mustafa, T., Horton, D.R., Cooper, W.R., Zack, R., Thinakaran, J., Karasev, A., Munyaneza, J.E. 2021. Stylet-probing behavior of two Bactericera species on host and non-host plants (Hemiptera: Psylloidea: Triozidae). Environmental Entomology. 50(4):919-928. https://doi.org/10.1093/ee/nvab031.
DOI: https://doi.org/10.1093/ee/nvab031

Interpretive Summary: Zebra chip, an economically important disease of potato in the United States, is caused by a bacterial plant pathogen called Liberibacter (Lso) that is transmitted by potato psyllids when they feed upon the phloem of potato plants. Another psyllid, bindweed psyllid, also carries Lso, but it is not yet clear whether bindweed psyllid transmits this pathogen to potato. Researchers at the USDA-ARS in Wapato WA, in collaboration with scientists at Washington State University and University of Idaho, used electropenetography technology to compare the feeding behaviors of bindweed psyllid on host plants of this psyllid (field bindweed and sweet potato) and non-host plants (potato and matrimony vine). It was determined that bindweed psyllid readily feeds upon the phloem of host plants, but avoids the phloem of the non-host plants. Because bindweed psyllid avoided the phloem of potato, this psyllid is unlikely to transmit Lso to potato. Potato psyllid uses all four plants as hosts and readily fed from the phloem of all four plant species, but spent less time feeding from phloem of the sub-optimal hosts, field bindweed and sweet potato. These results provide a better understanding of how zebra chip disease is spread, and also provide important insight into the host plant use by psyllids.

Technical Abstract: Understanding host-use by psyllids (Hemiptera: Psylloidea) benefits from comparative studies of behavior on host and non-host plant species. While most psyllid species develop on one or a few closely related plant species, some species are generalized enough to develop on species across plant families. We used electropenetography (EPG) technology to compare probing activities of an oligophagous psyllid (Bactericera cockerelli) and a host-specialized psyllid (Bactericera maculipennis) on two species of Solanaceae (potato, Solanum tuberosum; matrimony vine, Lycium barbarum) and two species of Convolvulaceae (field bindweed, Convolvulus arvensis; sweet potato, Ipomoea batatas). Bactericera cockerelli develops on all four species, albeit with longer development times on Convolvulaceae. Bactericera maculipennis develops only on Convolvulaceae. Bactericera cockerelli fed readily from phloem of all four species, but probability of entering the phloem and duration of time in phloem was reduced on suboptimal hosts (Convolvulaceae) relative to behavior on Solanaceae. We observed instances of cycling between bouts of phloem salivation and ingestion in assays of optimal (Solanaceae) hosts not observed on Convolvulaceae. The Convolvulaceae-specialized Bactericera maculipennis failed to feed from phloem of non-hosts (Solanaceae). Both psyllid species readily ingested from xylem of all plant species, irrespective of host status. Our finding that phloem feeding by B. maculipennis did not occur on potato has implications for understanding epidemiology of phloem-limited psyllid-vectored plant pathogens. Our results also showed that EPG assays detect subtle variation in probing activities that assist in understanding host use by psyllids.