Mechanical transmission of Potato virus Y, including seed cutting is not a contributing factor to increased virus in field production

Authors: DUELLMAN, KASIA - University Of Idaho; Whitworth, Jonathan; LENT, MELINDA - University Of Idaho; BERTRAM, MELISSA - University Of Idaho; RANDALL, JILL - University Of Idaho

Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2022
Publication Date: 6/19/2022
Citation: Duellman, K.M., Whitworth, J.L., Lent, M.A., Bertram, M.C., Randall, J.C. 2022. Mechanical transmission of Potato virus Y, including seed cutting is not a contributing factor to increased virus in field production. Plant Health Progress. https://doi.org/10.1094/PHP-02-22-0011-RS.
DOI: https://doi.org/10.1094/PHP-02-22-0011-RS

Interpretive Summary: Potato virus Y (PVY) can be transmitted from infected potato plants to healthy ones by aphids and by mechanical transmission. One continuing concern by growers is that cutting seed can be one of the mechanical ways to spread virus to new seed pieces resulting in higher PVY in a field. The literature suggests this type of movement does not contribute to increased virus in the field. In two experiments in the field and in a greenhouse, infected seed was cut and planted along with uncut whole seed and the resulting plants were tested for PVY using ELISA, a standard test for virus. These results validate the work of others that mechanical spread of PVY is not a concern.

Technical Abstract: Potato virus Y (PVY) infects a wide host range. Commercial potato growers continue to express concern that cutting seed may move PVY from infected seed to healthy ones and lead to increased incidence of PVY in the field. However, the bulk of the literature suggests such movement is of little to no importance. Here, we present an overview of the literature relating to the movement of PVY via the cutting process and the results of experiments that we conducted that add to the existing pool of knowledge. In a greenhouse experiment, a knife contaminated with PVY did not transmit the virus to subsequent cut tubers, and in a field experiment, PVY incidence for small whole seed compared to cut seed from the same seed lot were similar. Our research results corroborate those of others, and we recommend that growers continue to use the type of seed, whether cut seed pieces or whole tubers, best suited for their operations with respect to PVY management as these results show that there is little risk of mechanical transmission in normal seed and commercial operations.