A robust potato tuber tissue collection method to investigate potato virus Y, potato mop-top virus, and tobacco rattle virus localization patterns

Authors: Ingram, Jason; MUDRACK, ERICA - Cornell University; TRAN, LISA - Idaho Crop Improvement Association, Inc; CURTIS, MICHELLE - Cornell University; MATTUPALLI, CHAKRADHAR - Washington State University; GUDMESTAD, NEIL - North Dakota State University; CHARKOWSKI, AMY - Colorado State University; GROVES, RUSSELL - University Of Wisconsin; BABLER, BROOKE - University Of Wisconsin; Whitworth, Jonathan; FROST, KEN - Oregon State University; BROWN, CHARLES - Non ARS Employee; KARASEV, ALEXANDER - University Of Idaho; GRAY, STEWART - Retired ARS Employee; Filiatrault, Melanie

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/2025
Publication Date: 4/28/2025
Citation: Ingram, J.T., Mudrack, E., Tran, L., Curtis, M., Mattupalli, C., Gudmestad, N., Charkowski, A., Groves, R., Babler, B., Whitworth, J.L., Frost, K., Brown, C., Karasev, A., Gray, S., Filiatrault, M.J. 2025. A robust potato tuber tissue collection method to investigate potato virus Y, potato mop-top virus, and tobacco rattle virus localization patterns. Plant Disease. https://doi.org/10.1094/PDIS-11-24-2453-RE.
DOI: https://doi.org/10.1094/PDIS-11-24-2453-RE

Interpretive Summary: Potato is one of the most valuable food crops grown in the United States. Because potatoes are produced by planting tubers from the previous year’s crop, diseases and pests of potatoes can spread rapidly causing significant losses. Detection of potato viruses can be difficult because some new emerging viruses do not induce reliable foliar symptoms or symptoms may not be expressed in certain potato cultivars. Therefore, there is a need for improving testing for viral pathogens of potato. Here, we determined the spatial and temporal distribution of three viruses (potato virus Y, PVY; potato mop-top virus, PMTV; and tobacco rattle virus, TRV) in tuber tissue of several potato cultivars and developed a tuber tissue sampling strategy that optimized the detection of these viral pathogens in harvested tubers using molecular methods. The workflow provides earlier detection of pathogens of potatoes, offering a robust alternative to current testing methods.

Technical Abstract: Potato tuber necrosis-causing viruses (potato virus Y, PVY; potato mop-top virus, PMTV; and tobacco rattle virus, TRV) can be difficult to identify using visual foliar symptoms. Using tuber samples collected from seven locations and 12 cultivars during 2017-2019, we developed a molecular assay using customized Whatman Flinders Technology Associates Plantsaver® Cards (FTA cards) and a reverse-transcription polymerase chain reaction (RT-PCR) for efficient sample collection and nucleic acid extraction. Sampling from multi-locations on a tuber accounted for virus localization differences thereby improving virus detection. PMTV and PVY were detected more frequently on the stem-end, TRV on the rose-end, and potato virus S was evenly detected across stem-end to rose-end axis of the tubers. Regardless of sampling location on the tuber, tissue excised from surface to 0.5 cm deep provided the best detection for all four viruses. For PVY, PMTV, and TRV, the proportion of tubers with virus detected from field samples was highest at 100, 150, and 175 days after harvest, respectively. However, the probability of detecting PMTV and PVY 25 days after harvest was not different than the probability of detection at their peak detection times after harvest. The probability of TRV detection was lower at 25 days after harvest than at 175 days after harvest (P < 0.05). Collectively, this study indicates that there is no need to delay sampling or to break tuber dormancy when using FTA cards to detect PVY.