Resistance in Transgenic Potato Expressing the Potato Leafroll Virus Coat Protein Gene. L. M. Kawchuk. Research Station, Agriculture Canada, Vancouver, British Columbia V6T 1X2, University of British Columbia, Vancouver, British Columbia V6T 2A2, Canada. R. R. Martin(1), and J. McPherson(2). (1)Research Station, Agriculture Canada, Vancouver, British Columbia V6T 1X2, and (2)Department of Plant Science, University of British Columbia, Vancouver, British Columbia V6T 2A2, Canada. MPMI 3:301-307. Accepted 24 April 1990. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1990.

The coat protein gene of potato leafroll virus (PLRV), a member of the luteovirus group, was inserted into potato via a gene transfer mediated by Agrobacterium tumefaciens. Introduced as a chimeric gene under the control of the duplicated cauliflower mosaic virus 35S promoter, transcription levels were high but only low levels of coat protein were detected. Coat protein accumulation ranged from undetectable levels to a maximum of 0.01% of total leaf protein. Inoculation of transgenic plants with PLRV resulted in low virus titers that remained low or decreased indicating sustained resistance. High PLRV inoculation levels achieved with 25 viruliferous aphids did not overcome the resistance. This resistance will have practical applications for the control of PLRV and may also help to understand the mechanisms of virus infection.