VIEW ARTICLE

Molecular Plant Pathology

Transgenic Burley and Flue-Cured Tobacco with Resistance to Four Necrotic Isolates of Potato Virus Y. Sudarsono , Department of Crop Science, Box 7620, ; J. B. Young(2), S. L. Woloshuk(3), D. C. Parry(4), G. M. Hellmann(5), E. A. Wernsman(6), S. A. Lommel(7), and A. K. Weissinger(8). (2)(3)(7)Department of Plant Pathology, Box 7616, North Carolina State University, Raleigh 27695; (4)(6)(8)Department of Crop Science, Box 7620; (5)RJR Nabisco, Inc., Bowman Gray Technical Center, Winston-Salem, NC 27102. Phytopathology 85:1493-1499. Accepted for publication 19 July 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/Phyto-85-1493.

Transgenic burley (cultivars KY14, NC3433-33, and TN90) and fluecured (cultivar K326) tobacco with resistance to four necrotic isolates of potato virus Y (PVY) were constructed. These tobacco cultivars were transformed with a chimeric gene designed to express the coat protein (CP) from the necrotic Chilean isolate of PVY. CP expression among R₀ plants was undetectable by indirect enzyme-linked immunosorbent assay and Western blot (immunoblot) analysis. Transgenic R₀ plants that harbored from one to five neomycin phosphotransferase II (NPT II) transgene loci were identified. Although the NPT II and the PVY CP chimeric genes were linked within a common T-DNA, no correlation was found between the number of NPT II and CP transgenes. Inoculation of 41 independent transgenic KY14 R₀ plants with PVY-Chilean identified eight resistant plants, while inoculation of 30 transgenic K326 R₀ plants identified six resistant plants. Inoculation of 17 transgenic NC3433-33 R₀ plants with PVY-Chilean identified six resistant plants, while inoculation of 50 transgenic TN90 R₀ plants with PVY isolate VAM B resulted in nine resistant plants. Progeny derived from PVY-inoculated but symptomless R₀ plants were also resistant to the Chilean, Europe H, M^sN^r, N-Canada, and VAM B isolates of PVY, demonstrating sexual transmission of the transgenes that condition resistance. We discuss the ability of the PVY-Chilean CP gene to protect transgenic tobacco K326, KY14, NC3433-33, and TN90 from infection by four necrotic isolates of PVY. The flue-cured tobacco cultivar K326, which carries a gene simultaneously conferring resistance against root-knot nematode and susceptibility to PVY strain M^SN^R, is protected against this strain when transformed with the PVY-Chilean CP gene.