March 28, 2008

It’s the time of year when some tobacco farmers prepare to purchase tobacco transplants. But now word comes that plants with blue mold have been found in Florida, and any plants headed to Kentucky could be infected. This is a yearly concern, but one way to reduce that worry is to think local.

Healthy and vigorous transplants serve as the foundation for a successful tobacco crop. Kenny Seebold, a plant pathologist with the University of Kentucky College of Agriculture, said farmers can reduce the odds of bringing this unwanted disease into their tobacco fields by producing their own plants or buying them from a local producer. Local producers also must think preventively and manage their operations to minimize disease problems as well.

Seebold said he’s already received word of blue mold found in tobacco transplants in northern Florida. Some of the worst epidemics of blue mold in Kentucky were associated with early arrival of the disease during production of transplants.

“There’s no imminent threat to producers in Kentucky at the moment, since we’re not too far along in the transplant production cycle, and recent weather patterns haven’t necessarily threatened us,” he said. “On the other hand, it’s extremely important now to keep southern-grown transplants out of our state if at all possible.”

Historically, Florida produced quite a few seedling plugs that were sold in Kentucky, but the company that grew the bulk of these plants phased out tobacco transplants in 2007. Still, there may be other companies or individuals in Florida and possibly Georgia that will raise plugs or finished plants that might come into Kentucky.

“The threat from the disease is low, but the status could change quickly depending upon the extent of the epidemic in the south and the weather that we experience over the next couple of months,” Seebold said.

The blue mold pathogen normally does not overwinter in Kentucky and must be introduced for epidemics to begin each year. The pathogen is introduced aerially from areas where tobacco is grown, from infected wild tobacco or on contaminated transplants.

Any tobacco grown in Florida potentially could carry blue mold and movement of plants from there likely would mean introduction of the disease into other areas. Plants grown in Georgia and Tennessee may or may not have been exposed, and pose less of a threat.

“This threat level would increase if the disease is found in those areas, or if weather conditions and patterns indicate potential exposure,” he said. “Because there is a threat, I’d say we should avoid these plants as well if at all possible.”

Proper management of transplants during the production cycle is critical to managing blue mold and other diseases. Prevention is the best defense against blue mold in float systems and conventional plant beds. From this point forward, Kentucky plant producers should manage their operations to prevent blue mold from developing in their transplants. This means good growing practices and routine application of Dithane DF to plants from the time they are dime-sized through setting into the field.

More information is available in the 2008 Kentucky Tobacco Production Guide. Copies can be obtained through county offices of the UK Cooperative Extension Service. Growers can monitor the status of blue mold in the United States on Seebold’s Kentucky Tobacco Disease Information Page.

News Topics: