Colorado potato beetle (Leptinotarsa. decemlineata) prefer Solanum jamesii populations on which they were originally observed in the wild

Authors: COHEN, ZACHARY - University Of Wisconsin; Bamberg, John; SCHOVILLE, SEAN - University Of Wisconsin; GROVES, RUSSEL - University Of Wisconsin; BRADFORD, BENJAMIN - University Of Wisconsin

Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/18/2023
Publication Date: 4/6/2023
Citation: Cohen, Z., Bamberg, J.B., Schoville, S., Groves, R., Bradford, B. 2023. Colorado potato beetle (Leptinotarsa. decemlineata) prefer Solanum jamesii populations on which they were originally observed in the wild. American Journal of Potato Research. 1-5 (2023). https://doi.org/10.1007/s12230-023-09911-9.
DOI: https://doi.org/10.1007/s12230-023-09911-9

Interpretive Summary: The potato crop is the world's most important vegetable, but can benefit from genetic improvement through breeding. Fortunately, there are many wild and cultivated potato relatives rich in useful traits. These are collected, preserved, evaluated and distributed from the U.S. Potato Genebank at Sturgeon Bay, Wisconsin. One such wild species, Solanum jamesii (jam), grows naturally in the United States, and serves as a handy model of how natural factors impact genetic resources in the wild. It shares the same natural range as the Colorado potato beetle (CPB), a major pest of the potato crop. We tested jam plants obtained from various spots in the wild, some on which CPB had been observed in the wild and some not. The jam for which CPB had been observed in nature were also more attractive to CPB when grown artificially in field plots in Wisconsin. This shows that documentation of CPB absence on jam in the wild could serve as an easy prediction of which jam will be most useful in potato breeding.

Technical Abstract: Plant preference in agricultural pests is a prerequisite for expansion onto cultivated crops, but there has been limited research on how an insect determines host plant suitability. We investigated Colorado potato beetle Leptinotarsa decemlineata (CPB) performance on various populations of the wild potato Solanum jamesii (jam), with which it has overlapping natural range in the southwest United States. Herbivory was measured in no-choice feeding assays in the greenhouse and common garden field plots in Wisconsin. The jam populations were categorized according to whether CPB had been observed to be present in their original germplasm collection records. Herbivory on all jam populations was very low compared to the tuberosum cultivar control. In the no-choice greenhouse assay, all jam were equally consumed by CPB. But in field plots where choice was allowed, significant CPB were more attracted to jam populations on which CPB had been observed in the wild. Although documenting the presence of CPB on wild jam populations was non-systematic and qualitative in germplasm collecting expeditions over multiple years, that observation does appear to have some value in predicting which jam will be more attractive to CPB in Wisconsin field conditions.