Tobacco (Nicotiana tabacum) remains the most economically important agronomic crop in North Carolina, which ranks first in US tobacco production. In 2004, 159,000 acres were produced yielding about 352 million pounds. Two types of tobacco are produced, differentiated by their genetics, growth characteristics, agronomic practices, uses, and location within the state. Flue-cured tobacco accounts for all but about 9 million acres of the state's crop and is grown in the Piedmont and Coastal Plain areas. Leaves are pulled from the stalk as they ripen and cured in barns using heat. Burley tobacco, grown in the mountains, is harvested by cutting the stalk and curing it without heat.
Diseases are major limiting factors of production for both types of tobacco. Flue-cured disease losses generally range from one to two percent statewide, not including costs of control. However, losses in individual counties range up to 25% and total losses occur in some fields. Recently, the most economically important diseases have been caused by viruses, soil-borne fungi, and soil-borne bacteria. The most important burley diseases are blue mold, soil-borne fungal diseases, and aphid-transmitted viruses. Blue mold, an air-borne downy mildew, frequently destroys over one third of the NC burley tobacco crop.
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More information about disease in tobacco is available from the Plant Disease and Insect Clinic or Asimina Mila.