Search Results

14 results

  1. Tob. Reporter, 1992, 119-9, p. 62-5, Tob. Sci, 1992, 36, p. 45-8, ISSN.0361-5693

    Control of tobacco budworm larvae (Lepidoptera:Noctuidae) in tobacco seed nurseries with pyrethroid insecticides

    JACKSON D.M.; GWYNN G.R.
    USDA-ARS, Crops Research Lab, Oxford, NC, USA
    Twelve insecticides in various formulations and application procedures were evaluated for control of tobacco budworm larvae on inflorescences and seed pods of flue-cured tobacco in nurseries for seed production. Backpack spray applications of...
  2. Tob. Sci., 1974, 18-01, p. 1-3, ISSN.0082-4523

    Differences among tobacco varieties and breeding material in chlorophyll content during content during curing

    GWYNN G.R.; McCLURE W.F.
    Oxford Tobacco Research Laboratory, Southern Region, Agricultural Research Service, U. S. Department of Agriculture, Oxford, North Carolina USA; North Carolina State University, Raleigh, North Carolina USA
    A nondestructive electronic method for measuring chlorophyll by dual wavelengths during the yellowing phase of tobacco curing was used in several experiments. The general objectives were to apply this method to several varieties-to characterize...
  3. Tob. Sci., 1974, 18-09, p. 23-25, ISSN.0082-4523

    Modified systems of production and harvesting of flue-cured tobacco

    GWYNN G.R.
    Oxford Tobacco Research Laboratory, Southern Region, Agricultural Research Service, U. S. Department of Agriculture, Oxford, North Carolina USA; North Carolina State University, Raleigh, North Carolina USA
    Two studies were conducted to measure the effect of reduced number of harvestings on different cultivars. In one study the tobacco was harvested in one, two, and three harvests with leaf population varying according to number of harvests. In the...
  4. Tob. Sci., 1973, 17-37, p. 108-109, ISSN.0082-4523

    Effect of maturity on germination of seed of six tobacco cultivars

    GWYNN G.R.
    Oxford Tobacco Research Laboratory, Southern Region, Agricultural Research Service, United States Department of Agriculture, Oxford, North Carolina USA; North Carolina State University, North Carolina USA
    This study was undertaken to determine the effect of early seed harvest on the viability of tobacco (Nicotiana tabacum L) seeds. Seeds of six tobacco cultivars were harvested 14, 18, 22, 26, and 30 (1968 only) days after anthesis. Seeds harvested 14...
  5. Tob. Sci., 1973, 17-43, p. 131-133, ISSN.0082-4523

    Technique for evaluating the yellowing rates of flue-cured tobacco

    McCLURE W.F.; GWYNN G.R.
    North Carolina State University, North Carolina USA; Oxford Tobacco Research Laboratory, Southern Region, Agricultural Research Service, U.S. Department of Agriculture, Oxford, North Carolina USA
    A dual-wavelength technique was developed for monitoring chlorophyll degradation during the yellowing phase of flue-curing tobacco. The first-order model C = Co10kt, where C = chlorophyll concentration at any time t, Co = chlorophyll concentration at...
  6. Tob. Sci., 1972, 16-23, p. 84-85, ISSN.0082-4523

    Simplified methods of pollen storage in tobacco

    GWYNN G.R.
    Plant Science Research Division, Agricultural Research Service, U.S. Department of Agriculture, Georgia Coastal Plain Experiment Station, Oxford, North Carolina USA; North Carolina State University, North Carolina USA
    The present method of storing tobacco (Nicotiana tabacum L.) pollen in gelatin capsules over silica gel in a refrigerator at 5°C was compared to several other methods designed to be more economical and/or convenient and at the same time maintain a...
  7. Tob. Sci., 1970, 14-01, p. 1-6, ISSN.0082-4523

    Characterization of oxidative browning in flue-cured tobacco I. A method for evaluating varietal discoloration potentials

    JOHNSON W.H.; GWYNN G.R.
    Biological and Agricultural Engineering Department, North Carolina State University USA
    A method was developed and tested for characterizing oxidative browning in tobacco during curing, utilizing standardized procedures. Nearly identical cultural practices and curing conditions were imposed on three varieties of Nicotiana tabacum L....
  8. Tob. Sci., 1970, 14-34, p. 121-123, ISSN.0082-4523

    Pale yellow tobaccos and their hybrids with flue-cured tobacco

    GWYNN G.R.; CHAPLIN J.F.; BURK L.G.
    Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture, Oxford, NC USA; North Carolina State University, North Carolina USA
    Chlorophyll-deficient Tobacco Introductions (T. I. s) carrying the factor(s) for "Pale Yellow," were crossed with flue-cured tobacco varieties. Hybrids and parents were tested for agronomic and smoke flavor characteristics, and chemical constituents....