Research Accomplishment Reports 2007

Dark Tobacco Research and Extension Programs

W. A. Bailey
Department of Plant & Soil Sciences

 

Project Description

Dark tobacco research and extension programs are a joint, multi-state effort of the University of Kentucky and the University of Tennessee that is focused on improving profitability of dark tobacco production in approximately 30 counties in western Kentucky (23 counties) and central Tennessee (7 counties). 

Extensive research trials are conducted at two University research stations in western Kentucky (Princeton, KY and Murray, KY), and at the University of Tennessee Highland Rim Research and Education Center in Springfield, TN.  In addition, extensive on-farm research is conducted throughout the major dark tobacco production areas of Kentucky and Tennessee.  Since the 2003 production season, 107 replicated research trials have been conducted at the three major research stations, and 58 replicated research trials have been conducted on private farms.  Trials conducted  have been focused on major dark tobacco production issues such as nitrogen use efficiency, fungicide screening for foliar disease control, insecticide screening for hornworm and budworm control, variety development, topping practices and sucker control practices, harvest timing, and air/fire-curing practices. 

A major research project has involved establishment and verification of University nitrogen rate recommendations for dark tobacco.  This research has established more defined guidelines for nitrogen use on dark tobacco to reduce excessive nitrogen fertilization. 

Another major research project has been to develop guidelines for double crop curing systems in dark tobacco.  Double crop curing refers to the practice of curing two crops of dark-fired tobacco in the same barn and season, thereby doubling the use efficiency of barns and eliminating some of the need for new barn construction. 

Another major issue that has been addressed by dark tobacco research and extension programs is implementation of tobacco weed control guidelines by growers and potential for post-transplant control of troublesome perennial broadleaf weeds that routinely cause significant yield reductions in dark tobacco.  Experimental postemergence herbicides with potential for broadleaf weed control efficacy and crop safety in dark tobacco are being continually tested in an effort to provide growers with more tools for weed control in dark tobacco and other tobacco types.

Impact

The nitrogen rate research project has had economic, social, and environmental impacts.  This research has improved economic profitability for dark tobacco growers, reduced levels of carcinogens in cured tobacco leaf that are associated with high nitrate levels, and reduced environmental nitrate load by reducing the amount of total nitrogen used for dark tobacco production.  Results of this work have been embraced by tobacco manufacturers who have encouraged and enforced these recommendations for their growers.  This work has resulted in a net savings of at least $1.3 million annually to KY/TN dark tobacco growers who were routinely using excessive nitrogen rates. 

Implementation of double crop curing guidelines along with increased demand for dark-fired tobacco has resulted in a major increase in the use of double crop curing systems since 2005, and has resulted in an estimated barn construction savings to growers of at least $12.5 million. 

Based on informal survey results, 80% of dark tobacco growers now follow the tobacco weed control recommendations of the University of Kentucky and the University of Tennessee.  This compares to only 45% of growers that followed University weed control recommendations in 2003.  Increased implementation of University weed control guidelines by dark tobacco growers has resulted in a net savings of at least $150,000 annually.

Publications

Information generated by dark tobacco research and extension programs have resulted in numerous journal article pulications, abstracts, and extension publications, including an annual comprehensive tobacco production guide published by the University of Kentucky that is easily available to dark tobacco growers in Kentucky and Tennessee.  Many of the extension publications have been published jointly by the University of Kentucky and the University of Tennessee for distribution in both states.  The following are selected publications related to reported impacts.

JOURNAL ARTICLES

Bailey, W. A.  2007.  Dark tobacco (Nicotiana tabacum) tolerance to trifloxysulfuron and halosulfuron.  Weed Technol.  21(4):1016-1022.

Bailey, W. A., L. R. Fisher, J. W. Wilcut, W. D. Smith, and V. B. Langston.  2004.  Tobacco (Nicotiana tabacum L.) tolerance to pre-transplant and postemergence applications of diclosulam.  Tobacco Sci. (2001) 45:26-29.

ABSTRACTS

Pitt, W. and A. Bailey.  2008.  Influence of double-crop curing practices on leaf chemistry of dark fire-cured tobacco.  Proceedings of 43rd Tobacco Workers Conference, Savannah, GA.  Paper 5.

Bailey, A., R. Pearce, T. Lax, and R. Hill.  2008.  Performance of experimental herbicides for weed control in conservation tillage dark tobacco.  Proceedings of 43rd Tobacco Workers Conference, Savannah, GA.  Paper 19.

Bailey, W. A. and R. C. Pearce.  2007.  Experimental herbicide systems for no-tillage dark tobacco.  Proceedings of 2007 CORESTA Joint Meeting of Agro-Phyto Study Groups, Krakow, Poland.  Paper AP 30.

Bailey, W. A., T. W. Lax, R. A. Hill, and W. D. Pitt.  2006.  Nitrogen fertilization practices in dark tobacco.  Proceedings of 42nd Tobacco Workers Conference, Charleston, SC.  Paper 34.

Bailey, W. A.  2004.  Influence of nitrogen rate on growth, yield, and leaf chemistry of dark tobacco.  Proceedings of 2004 CORESTA Congress, Kyoto, Japan.  Paper AP 01.

EXTENSION PUBLICATIONS

Seebold, K., B. Pearce, A. Bailey, J. D. Green, G. Palmer, G. Schwab, G. Halich, L. Powers, W. Snell, L. Townsend, G. Duncan, L. Wells, and J. Wilhoit.  2008.  2008 Kentucky Tobacco Production Guide.  ID-160.  Cooperative Extension Service, University of Kentucky, College of Agriculture.

Pearce, B, A. Bailey, and G. Palmer.  2006.  Alternative fertilizer nitrogen sources for tobacco production.  Soil Science News & Views.  Plant & Soil Sciences publication series.  Vol. 26, No. 3.  5 pages.  Cooperative Extension Service, University of Kentucky, College of Agriculture.

Pearce, B., G. Palmer, and A. Bailey.  2006.  Revised nitrogen fertilizer recommendations for tobacco.  Plant & Soil Sciences fact sheet TOB-1-06.  Cooperative Extension Service, University of Kentucky, College of Agriculture.

Bailey, A.  2008.  Double crop curing dark tobacco.  AGR-196.  Cooperative Extension Service, University of Kentucky, College of Agriculture