Blue mold continues to spread in Kentucky, with new cases being found in western and central Kentucky. Previous cases were reported in eastern Kentucky, bringing the number of counties reporting the disease to a dozen.Blue mold is a weather-sensitive disease that spreads both locally and over long distances through the air and on transplants. The disease is concentrated primarily in the eastern portion of the state, and most cases in this area can be traced back to the use of plug plants imported from Florida, said Kenny Seebold, plant pathologist with the University of Kentucky College of Agriculture.“The presence of blue mold in central and western Kentucky indicates that we are likely seeing movement of blue mold from either an established source or an undiscovered source,” he said. “These sources can produce many spores that will serve to spread the disease further across the region.”Weather patterns in the coming days are favorable for the development and spread of the disease across much of the state. To be on the safe side, Seebold urges growers to keep up preventive applications of fungicide.Despite the increasingly widespread nature of the epidemic, damage to the tobacco crop has been minimal overall, he said. The most severe cases of blue mold thus far have occurred where systemically infected seedlings were set. The systemic phase of blue mold can be devastating on seedlings. At best, these plants fail to grow and can serve as a source of spores that will fuel further outbreaks. At worst, these plants can wilt and die. Systemic blue mold cannot be cured with fungicides. Plants should be destroyed and fields reset, if practical, in situations where systemic blue mold is prevalent on young tobacco.Counties with reported cases of blue mold are Adair, Bath, Bourbon, Boyle, Carter, Greenup, Magoffin, Mercer, Menifee, Morgan, Warren, and Wolfe.A list of fungicides that can be used on tobacco can be found here  or in Kentucky Pest News No. 1095()See the Kentucky Tobacco Disease Information Web site for regular updates on blue mold and other diseases.