Unlike with many crops, tobacco producers are encouraged to first consider the disease resistance characteristics of a variety before adopting it. While yield and quality are important, diseases in tobacco can be so limiting that they should be given first consideration. Some of the most widely plated tobacco varieties have been available for many years. However, newer varieties developed in recent years combine disease resistance with good yield potential.
Growers are encouraged to closely evaluate variety trials data when making a decision, and always try new varieties on a limited acreage the first year to determine suitability for their farm.
- Consider disease resistance first. Tables in the “Managing Diseases,” chapter of the NC Flue-Cured Tobacco Guide, provide a list of popular varieties and their ratings for resistance to black shank and Granville wilt—the two diseases that pose the most serious threats to flue-cured crops in North Carolina. Determine the level of disease resistance that you need based on field history, length of rotation, and crops grown in rotation with tobacco.
- Consider agronomic characteristics, such as yield, quality, and holding ability, after you determine the necessary level of disease resistance. Multi-year data, such as the 3-year average and the 2-year average are better than single-year data. Averaging information across years removes much of the environmental effect and provides a stable picture of a variety’s performance over time. However, single-year data and individual location data) are helpful when you wish to see data collected from a specific growing region and under certain climatic conditions.
- Consider holding ability—the ability of a variety to hold its ripeness during the harvest period. For producers with limited barn space, this can be an important consideration.
Holding ability refers to the ability of a variety to maintain it ripeness in the field during the harvest period. Because of the logistics of harvesting and curing tobacco, limited barn space and labor can make holding ability an important consideration.
Holding ability is measured by comparing the value of the last priming of varieties based on harvest schedule. The following tables show results from holding ability trials conducted at NC State for several popular varieties.
The purpose of the Regional Minimum Standards Program is to insure that varieties planted by growers are acceptable to the tobacco industry. Once a breeding line is genetically stable, it can be entered into the Regional Small Plot Test (RSPT) conducted cooperatively by university researchers in Georgia, South Carolina, North Carolina, and Virginia. Breeding lines that pass the minimum standards for chemical quality in the RSPT can be entered in the Regional Farm Test (RFT). In the RFT, researchers plant breeding lines at 11 locations. Six of the RFT locations are in North Carolina. If a breeding line passes the RFT, which includes a smoke test, it is eligible for release as a commercial variety. (From Page 27 of Tobacco Guide)