VIEW ARTICLE

Disease Detection and Losses

Effect of Potato Virus Y and Tobacco Mosaic Virus on Field-Grown Burley Tobacco. R. C. Sievert, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture, Tobacco Experiment Station, Greeneville, TN 37743, Present address: Tobacco Research Laboratory, Route 2, Box 16G, Oxford, NC 27565; Phytopathology 68:823-825. Accepted for publication 2 November 1977. Copyright © 1978 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-68-823.

Yield, grade index, crop index, value per kilogram, and value per hectare were reduced when Burley 37 became infected with tobacco mosaic virus (TMV), potato virus Y (PVY), or both. A greater reduction was caused by PVY than by TMV, but the two viruses together caused the greatest reduction. Similarly, TMV+PVY caused greater variation from normal of chemical constituents than did either PVY or TMV alone. Compared to healthy tobacco, PVY-infected tobacco had less nicotine and TMV-infected tobacco had less α-amino nitrogen, but tobacco infected with TMV+PVY had less water-soluble acids, nicotine, phenols, and α-amino nitrogen and a lower percentage of its total nitrogen was soluble. Tobacco infected with TMV+PVY had more nitrate and insoluble nitrogen. Flowering was delayed in plants infected with TMV or TMV+PVY, but PVY infection alone had little effect on flowering.