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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Rangeland Resources & Systems Research » Research » Publications at this Location » Publication #407557

Research Project: Adaptive Grazing Management and Decision Support to Enhance Ecosystem Services in the Western Great Plains

Location: Rangeland Resources & Systems Research

Title: Landscapes with higher crop diversity have lower aphid species richness but higher plant virus prevalence

Author
item PITT, WILLIAM - Colorado State University
item KAIRY, LISA - Colorado State University
item MORA, VICTOR - Colorado State University
item Peirce, Erika
item JENSEN, ANDREW - Northwest Potato Research Consortium
item BRADFORD, BENJAMIN - University Of Wisconsin
item GROVES, RUSSEL - University Of Wisconsin
item CHRISTENSEN, TESS - Agro Engineering
item MACRAE, IAN - University Of Minnesota
item NACHAPPA, PUNYA - Colorado State University

Submitted to: Journal of Applied Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/12/2024
Publication Date: 5/24/2024
Citation: Pitt, W.J., Kairy, L.R., Mora, V., Peirce, E.S., Jensen, A.S., Bradford, B., Groves, R., Christensen, T., MacRae, I., Nachappa, P. 2024. Landscapes with higher crop diversity have lower aphid species richness but higher plant virus prevalence. Journal of Applied Ecology. 61:1573-1586. https://doi.org/10.1111/1365-2664.14687.
DOI: https://doi.org/10.1111/1365-2664.14687

Interpretive Summary: While landscape influence on insect-vectored plant viruses is recognized, this research pioneers an exploration into landscape-scale crop diversity. We examined the landscape's crop composition (e.g., diversity, cover), aphid vectors, and potato virus Y (PVY) prevalence as PVY is a destructive virus transmitted by 65 aphid species. A two-year field investigation in Colorado's San Luis Valley used pan traps for aphid sampling and an antibody detection test for PVY incidence. Unexpectedly, diverse crops correlated with fewer aphid species. This may stem from the virus's broad host range and increased viral reservoir. Specific crops were key: PVY prevalence correlated positively with potatoes (hosts) and negatively with barley (non-hosts). This research enriches our understanding of disease dynamics in agriculture. Crop diversity's intricate role in aphid populations and virus prevalence advances spatial risk assessment models, enhancing PVY spread predictions during critical growth periods. These insights offer a fresh perspective on agroecosystems, potentially strengthening disease management strategies and securing crop production.

Technical Abstract: 1) Landscape composition can influence prevalence of insect-vectored plant viruses in agroecosystems; however, there is limited information on the effect of landscape-scale crop diversity on prevalence of insect-vectored viruses. 2) In this study, we investigated how landscape composition of crops (Shannon diversity of crops, percent crop cover) affects aphid vector communities and prevalence of aphid-transmitted potato virus Y (PVY), one of the most damaging plant viruses for potato production worldwide. The virus is transmitted by at least 65 aphid species, including potato colonizers and non-colonizers. 3) To test the influence of landscape composition of crops on PVY prevalence and aphid communities, we conducted a two-year field study in the San Luis Valley, Colorado where we sampled aphid communities biweekly using pan traps and quantified PVY incidence in potato fields using ELISA and determined the association with landscape variables (Shannon diversity index of crops and percent crop cover) surrounding the sampling sites. 4) We found that higher crop diversity led to decreased aphid species richness, but increased PVY incidence. Additionally, we found a positive association of potato (virus host) and a negative association of barley (virus non-host) with PVY incidence. 5) It is possible that the negative influence of crop diversity on aphid species richness was due to increased predation/parasitism and/or differences in land management between crops. Potato virus Y has a wide host range; hence, it is plausible that crop diversity led to increased PVY incidence due to increased inoculum in the landscape. 6) Synthesis and applications: In summary, we found that crop diversity influenced patterns of PVY prevalence and aphid communities, and that the host/non-host status of plant species potentially mediates this effect. These findings could help improve spatial risk assessment models which predict PVY spread during the growing season.