Black Shank and Granville Wilt Resistant Varieties
- 2011 Blank Shank and Granville Wilt Tables (PDF | 21KB)
- Bacterial Wilt Resistance Ratings for 2010 Flue-Cured Tobacco Production Guide (PDF | 12KB)
- Ratings for Resistance to Race 1 of the Black Shank Pathogen in Flue-Cured Tobacco (PDF | 15KB)
- 2009 Black Shank and Granville Wilt Resistant Varieties (PDF | 26KB)
- 2008 Flue-cured Tobacco Black Shank Resistance (PDF | 35KB)
- 2008 Flue-cured Tobacco Granville Wilt Resistance (PDF | 58KB)
- 2007 Black Shank and Granville Wilt Resistant Varieties (PDF | 36KB)
Blue Mold Forecast - (link to North American Plant Disease Forecast Center)
Black shank is caused by a fungal pathogen that lives in the soil and attacks tobacco roots and stalks. Widespread continuous planting of flue-cured tobacco cultivars possessing single-gene (designated Ph) resistance to black shank enabled tobacco producers to dramatically reduce application of soil fungicides beginning in 1996. However, this has led to the breakdown in the efficacy of this resistance by shifting the distribution of the pathogen populations from host race 0 to race 1.
Tobacco Cyst Nematode
Tobacco cyst nematodes (TCN) are microscopic worms that live in the soil and feed on tobacco roots. TCN populations are thought to be decreasing in some fields due to the widespread planting of flue-cured cultivars with the Ph gene. Nematicide tests are conducted annually to evaluate their influence on nematode reproduction and tobacco yield and quality. TCN resistant cultivars are also evaluated for their potential.
Tobacco Mosaic Virus
Tobacco mosaic virus (TMV) is the most widely distributed virus that affects tobacco crops. TMV can be spread by contaminated clippings mowers in the greenhouse, from tobacco roots and stalks remaining in the soil from previous crops, from weed hosts such as horsenettle and ground cherry, and from contaminated objects and surfaces such as trays and sheets, and from manufactured tobacco products. Mosaic resistant cultivars can reduce damage and may help reduce residual virus in infested fields. If a TMV-resistant cultivar is planted, the entire field should be planted to the resistant cultivar.