Expression of the tomato pot-1 gene confers potato virus Y (PVY) resistance in susceptible potato varieties

Authors: ZHANG, CHEN - Michigan State University; ZARKA, KELLY - Michigan State University; ZARKA, DANIEL - Michigan State University; Whitworth, Jonathan; DOUCHES, DAVID - Michigan State University

Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/23/2020
Publication Date: 1/7/2021
Citation: Zhang, C., Zarka, K., Zarka, D., Whitworth, J.L., Douches, D.S. 2021. Expression of the tomato pot-1 gene confers potato virus Y (PVY) resistance in susceptible potato varieties. American Journal of Potato Research. 98:42-50.
DOI: https://doi.org/10.1007/s12230-020-09815-y

Interpretive Summary: Widely grown potato varieties, ‘Russet Norkotah’, ‘Silverton Russet’, and a new variety ‘Classic Russet’ and advanced breeding line MSE149-5Y were transformed with the tomato pot-1 gene in order to increase resistance to Potato virus Y (PVY). PVY causes yield loss, can cause necrotic tuber defects in certain varieties and is readily transmitted by aphids. The translation initiation factor 4E (eIF4E) has been implicated in naturally occurring resistance to PVY and is determined by the pot-1 locus in tomato. These transformed potato lines, A95.87.05 (from ‘Classic Russet’), MSE149.87.22 (from MSE149-5Y), SR.87.62 (from ‘Silverton Russet’), and RN1.87.09 (from ‘Russet Norkotah’) were tested, along with the corresponding untransformed varieties and breeding line, in the greenhouse against three strains of PVY and in the field with PVY. Greenhouse testing was done using mechanical inoculations of the three strains and in the field, plants were inoculated by aphids coming from PVY infected border rows planted in between each of the plots. Results showed that A95.87.05 (from ‘Classic Russet’) and MSE149.87.22 (from MSE149-5Y) had resistance against all three PVY strains in foliage and tubers while SR.87.62 (from ‘Silverton Russet’) and RN1.87.09 (from ‘Russet Norkotah’) were moderately susceptible to PVY in the foliage and tubers. Management of PVY levels in potato using overexpression of eIF4E can be used to provide PVY resistance to multiple strains of the virus.

Technical Abstract: The translation initiation factor 4E (eIF4E) has been implicated in naturally-occurring resistance to the Potato Virus Y (PVY) determined by the pot-1 locus in tomato. The susceptible potato varieties Russet Norkotah, Silverton Russet, and Classic Russet, along with the Michigan State University breeding line MSE149-5Y, were transformed with the pot-1 gene from Solanum hirsutum to achieve PVY resistance. Transgenic potato events and their non-transgenic controls were screened for PVY resistance against three PVY strains (PVYO, PVYN:O, PVYNTN) by enzyme-linked immunosorbent assay (ELISA) in greenhouse and in field trials. The event A95.87.05 (Classic Russet) and MSE149.87.22 (MSE149-5Y) had resistance against all three PVY isolates tested in both foliage and tuber under either greenhouse or field conditions. In contrast, SR.87.62 (Silverton Russet) and RN1.87.09 (Russet Norkotah), displayed moderate susceptibility to PVY in foliage during the growing season and increased level of infection in tubers. Transformation of PVY-susceptible potato varieties with the tomato pot-1 gene can be a useful tool for improving PVY resistance.