Charles S. Johnson

Professor

  • Professor, Extension Plant Pathologist

Education

Ph.D., Plant Pathology, 1985, North Carolina State University

M.S., Plant Pathology, 1981, North Carolina State University

B.S., Zoology, 1979, University of North Carolina, Chapel Hill

Experience

  • July 2000 – present: Extension Specialist and Professor, Southern Piedmont Agricultural Research and Extension Center, Blackstone, and Department of Plant Pathology, Physiology, and Weed Science, Virginia Polytechnic Institute and State University, Blacksburg
  • July 1991 – June 2000: Extension Specialist and Associate Professor, Southern Piedmont Agricultural Research and Extension Center, Blackstone, and Department of Plant Pathology, Physiology, and Weed Science, Virginia Polytechnic Institute and State University, Blacksburg

Selected Major Awards

• Philip Morris USA Award for Distinguished Achievement in Tobacco Science, 2000

• Class 7, ESCOP/ACOP Leadership Development Program, 1997-98

•Although I don’t have a teaching appointment, I am occasionally asked to deliver guest lectures to classes on the main campus in Blacksburg. I advise graduate students, and have had 1 PhD student and 2 M.S. students over the past 5 years. I supervised my former PhD student as a post-doctoral researcher during this time period, as well.

Program Focus

My research focuses on improving the management of economically important diseases and nematodes affecting tobacco and small fruits (especially strawberry). Increasing our understanding of pathogen life cycles and epidemiology to optimize management of plant diseases and nematodes, and using host resistance to achieve these goals, are “continuing threads” that run through my research activities. Much of my research involves traditional pesticide testing, but my intent is to combine these results with those from other, different, studies to identify alternative disease management strategies that are truly improvements. Much of my work is conducted in farmer’s fields, as well as in the laboratory, greenhouses, and fields at the Southern Piedmont Center. Most of my research is highly collaborative, working with other colleagues at the Southern Piedmont Center, as well as those at other ARECs and on the main campus in Blacksburg, and at other land grant universities, particularly North Carolina State University and the University of Kentucky.

Current Projects

  • Preparing for annual strawberry production without soil fumigation.
  • Potential biocontrol of Globodera tabacum solanacearum (tobacco cyst nematode) for flue-cured tobacco.
  • Clarifying resistance and/or tolerance to sedentary endoparasitic nematodes from the Rk2 genetic factor in flue-cured tobacco.
  • Improving management of Pythium damping-off and root rot in greenhouse tobacco transplant production systems.

Program Focus

By extensive cooperation with colleagues, industry, local extension agents, and growers, my extension program seeks to extend the best and latest research results on improving control of plant diseases and plant-parasitic nematodes to tobacco and small fruit producers in Virginia. My extension efforts start with listening to growers and extension colleagues regarding the problems farmers face, and how well various pest control methods work. I then identify research advances and industry developments that might be useful for Virginia farmers, and work with extension colleagues, local extension personnel, and growers to select those alternatives most practical under real farm conditions. With critical support from these groups, I conduct replicated on-farm trials, in addition to those on research stations. These field trials provide un-biased research results, as well as opportunities to actually demonstrate results to farmers and extension colleagues, agribusiness, and industry representatives. Between growing seasons, research results are “extended” to colleagues and growers through written publications, as well as by oral presentations directly to growers. I also periodically provide these results to regulatory agencies to assist them in managing the pest management options available to producers of small fruits and tobacco in Virginia.

Current Projects

  • Improving black shank management for burley tobacco in Virginia.
  • Identification of improved nematicidal compounds for tobacco cyst nematode control.
  • Identification of resistance to tobacco cyst nematodes in potential flue-cured tobacco cultivars.
  • Evaluating resistance to black shank and bacterial wilt in flue-cured tobacco under Virginia conditions.
  • Identifying alternative compounds for management of fungal leaf spots on tobacco.

Extension Publications

  • Freeman, J., T. Kuhar, M. Reiter, S. Rideout, H. Wilson, C. Johnson, A. Straw, H, Doughty, T. Hines, and C. Waldemeier. Commercial Vegetable Production Recommendations – Virginia. Virginia Cooperative Extension Publication No 456-420. Revised annually; I contributed 2011-2013.
  • Johnson, C. Disease and nematode management: tobacco. In Pest Management Guide: Field Crops. E.S. Hagood and D.A. Herbert, eds. Virginia Cooperative Extension Publication 456-016. Revised annually, 2008-2013.
  • Johnson, C. Weed control: tobacco. In Pest Management Guide: Field Crops. E.S. Hagood and D.A. Herbert, eds. Virginia Cooperative Extension Publication 456-016. Revised annually.
  • Johnson, C. Disease control. In Flue-Cured Tobacco Production Guide. T.D. Reed, ed. Virginia Cooperative Extension Publication 436-048. Revised annually.
  • Johnson, C. Weed control. In Flue-Cured Tobacco Production Guide. T.D. Reed, ed. Virginia Cooperative Extension Publication 436-048.Revised annually.
  • Pfeiffer, D., C. Johnson, K. Yoder, and J. Bergh, Commercial small fruits: Diseases and Insects. P. 2-1 to 2-16 in 2012 Pest Management Guide for Horticultural and Forest Crops. Virginia Cooperative Extension Publication 456-017. Revised annually; I contributed 2009-2012.
  • Pfeiffer, D., C. Johnson, K. Yoder, and J. Bergh, Commercial small fruits: Diseases and Insects. P. 2-17 to 2-18 in 2012 Pest Management Guide for Horticultural and Forest Crops. Virginia Cooperative Extension Publication 456-017. Revised annually; I contributed 2009-2012.

Research Publications

  • Parkunan, V., C.S. Johnson, and J.D. Eisenback. 2011. Influence of acibenzolar-S-methyl and mixture of Bacillus species on growth and vigor of cultivated tobacco. Tobacco Science, 48:7-14.
  • Parkunan, V., C.S. Johnson, B.C. Bowman, and C.X. Hong. 2011. First report of Phytophthora inundata associated with a latent infection of tobacco (Nicotiana tabacum). Plant Pathology 59:1164.
  • Parkunan, V., C.S. Johnson, B.C. Bowman, and C.X. Hong. 2010. Population structure, mating type, and mefenoxam sensitivity of Phytophthora nicotianae in Virginia tobacco fields. Plant Disease 94:1361-1365.
  • Parkunan, V., C.S. Johnson, and J.D. Eisenback. 2009. Effects of Php gene-associated versus induced resistance to tobacco cyst nematode in flue-cured tobacco. J. Nematology 41: 261-266.
  • Parkunan, V., C.S. Johnson, and J.D. Eisenback. 2009. Biological and chemical induction of resistance to the Globodera tabacum solanacearum in oriental and flue-cured tobacco. J. Nematology 41:203-210.
  • Johnson, C.S., E.A. Wernsman, and J.A. LaMondia. 2009. Effect of a chromosome segment marked by the Ph gene for resistance to Phytophthora nicotianae on reproduction of tobacco cyst nematodes. Plant Disease 93:309-315.
  • Johnson, C.S., J.A. Pattison, E.M. Clevinger, T.A. Melton, B.A. Fortnum, and A. Mila. 2008. Clarifying the source of black shank resistance in flue-cured tobacco. Plant Health Progress doi:10.1094/PHP-2008-0618-02-RS.