|CIMRHAKL, LAUNA - Washington State University|
|MOITAHEDI, HASSAN - Agnema, Llc|
|SATHUVALLI, VIDYASAGAR - Oregon State University|
|BROWN, CHARLES - Former ARS Employee|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2020
Publication Date: 3/20/2020
Citation: Quick, R.A., Cimrhakl, L., Moitahedi, H., Sathuvalli, V., Feldman, M.J., Brown, C. 2020. Elimination of tobacco rattle virus from viruliferous paratrichodours allius in greenhouse pot experiments through cultivation of Castle Russet. Journal of Nematology. 52:1-10. https://doi.org/10.21307/jofnem-2020-011.
Interpretive Summary: Corky ringspot (CRS) is a widespread potato disease caused by tobacco rattle virus (TRV) infection and vectored by stubby root nematodes (SRN) that feed on plant roots. Field affected by CRS are challenging to manage because the SRN vector is very difficult to eradicate and TRV has a broad host range. Scientists at the USDA-ARS laboratory in Wapato, WA in collaboration with researchers at Washington State University, AgNema LLC., and Oregon State University compared the ability of tobacco var. “Samsun NN”, alfalfa var. “Vernema”, and potato cultivars Russet Burbank and Castle Russet to sustain populations of SRN and influence the transmission of TRV over a four-month period, under two levels of inoculation pressure. Our results indicate that plant host type is the most influential factor affecting TRV infection status and SRN population size, followed by length of exposure, and inoculation pressure. Although all plant species were able to support SRN populations both alfalfa var. “Vernema” and Castle Russet effectively eliminated the presence of the TRV virus after three months of cultivation. These results suggest that both alfalfa var. “Vernema” and Castle Russet are resistant to TRV infection and may potentially be used to remediate fields affected by CRS
Technical Abstract: Corky ringspot (CRS) is a widespread potato tuber necrotic disease caused by Tobacco rattle virus (TRV) infection. In the Pacific Northwest, this virus is transmitted by the stubby root nematode (SRN) within the genus Paratrichodorous. Remediating CRS affected fields is a major challenge that can be mitigated by growing plant varieties that are resistant to TRV infection. Growing alfalfa has been shown to reduce TRV levels in CRS infested fields over time but the development of a potato cultivar with these same capabilities would be of great economic benefit to potato growers. Castle Russet is a new, potato clone that is immune to CRS symptoms. To assess its ability to reduce soil virus load, Castle Russet, tobacco var. “Samsun NN”, alfalfa var. “Vernema”, and Russet Burbank potato were grown in soils containing viruliferous SRN populations at two different inoculation pressures in greenhouse pot experiments. SRN population size and the presence of TRV was assessed over several months post-inoculation. Results indicate that plant host and length of exposure significantly influence SRN population dynamics whereas the TRV infection status of bait plants was significantly affected by both of these factors as well as inoculation pressure. These results suggest that both alfalfa var. “Vernema” and Castle Russet are resistant to TRV infection and may potentially be used to eliminate the virus from fields affected by CRS.