Browsing by Author "Reed, T. David"
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- 1998 Dark-fired Tobacco Production GuideReed, T. David; Jones, J. L.; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 1997)
- 2014 Flue-Cured Tobacco Production GuideReed, T. David; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 2014)An annually-produced guide to the production of flue-cured tobacco, issued in cooperation with the Virginia Bright Flue-Cured Tobacco Board.
- 2015 Flue-Cured Tobacco Production GuideReed, T. David; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 2015)An annually-produced guide to the production of flue-cured tobacco, issued in cooperation with the Virginia Bright Flue-Cured Tobacco Board.
- 2017 Flue-Cured Tobacco Production GuideReed, T. David; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 2017)An annually-produced guide to the production of flue-cured tobacco, issued in cooperation with the Virginia Bright Flue-Cured Tobacco Board.
- 2019 Flue-Cured Tobacco Production GuideReed, T. David; Johnson, Charles S.; Wilkinson, Carol A.; Barts, Stephen (Virginia Cooperative Extension, 2019)An annually-produced guide to the production of flue-cured tobacco, issued in cooperation with the Virginia Tobacco Board.
- Burley Tobacco Production Guide, 2008Peek, Danny R.; Reed, T. David; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 2008)This manual provides information on selecting varieties, greenhouse transplants, and management practices, fertilization, crop rotations, cover crops, sucker control, disease control, weed control, insect pests, curing, and other topics.
- Burley Tobacco Production Guide, 2011Peek, Danny R.; Reed, T. David; Johnson, Charles S.; Semtner, Paul J.; Wilkinson, Carol A. (Virginia Cooperative Extension, 2011)This report provides data on burley tobacco test plots, including agronomic practices, greenhouse management, fertilizer use, crop rotation, cover crops, sucker control, and control of diseases, weeds and insect pests. Also discusses curing practices.
- Burley tobacco variety information for 1995Wilkinson, Carol A.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 1995)
- Burley tobacco variety information for 1996Wilkinson, Carol A.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 1996)
- Burley tobacco variety information for 1999Wilkinson, Carol A.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 1998)
- Burley tobacco variety information for 2000Wilkinson, Carol A.; Peek, Danny R.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 2000)
- Burley tobacco variety information for 2001Peek, Danny R.; Wilkinson, Carol A.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 2001)
- Burley variety information for 1994Wilkinson, Carol A.; Reed, T. David; Johnson, Charles S. (Virginia Cooperative Extension, 1994)
- Comparison of Two Different Organic Fertilizer Sources for Flue-Cured TobaccoTucker, Lindy (Virginia Tech, 2015-12)Limited research is available to farmers and extension personnel seeking nitrogen fertilization recommendations for organic production of flue-cured tobacco in the Southside of Virginia. With growth in organic tobacco production in the area due to an increase in contracts offered by Santa Fe Natural Tobacco Company, the need for independent research on fertilization for the crop became clear. Research was conducted to compare the effects of the current organic tobacco fertilizer (8-5-5) to a new product considered to be more readily available (3-2-3) on flue-cured tobacco at the Southern Piedmont Agriculture & Research Extension Center near Blackstone, Virginia for the 2015 crop year. The effects of total nitrogen rate were also analyzed at rates of 65, 85, and 105 lbs of nitrogen to the acre. Additionally, sidedress applications of two products 13-0-0 and 16-0-0 were evaluated. Production other than fertilization treatments followed those of conventional tobacco. Plots were soil sampled a total of six times throughout the season and evaluated for nitrogen and ammonium content. Petiole samples of the fourth leaf from the top were taken from four plants in each plot four times throughout the season. Petioles were crushed and the extract analyzed for nitrate content. Total yields were determined after four harvests and the cured leaf graded for quality. Test results did not indicated a nitrogen rate effect for yield but there was a significant increase in yield with the 3-2-3 fertilizer compared to the 9-5-5.
- Development of a Greenhouse Tobacco Seedling Performance IndexClarke, Jodie Johnson (Virginia Tech, 2001-05-02)Tobacco seed performance is traditionally measured as percentage germination at 14 d under controlled laboratory conditions. However, under greenhouse conditions, seed lots with equal 14-d germination may exhibit substantial differences in uniformity of early seedling growth and spiral root incidence that impact the number of usable transplants. A seedling performance index (SPI) was developed to quantitatively describe greenhouse tobacco seedling performance. The 14-d emergence, relative leaf area uniformity, and seedling leaf area determined by computer image analysis were used to calculate the index. Greenhouse tobacco seed trials demonstrated that seed with the Rickard pellet had higher emergence, but the higher spiral root incidence associated with the Rickard pellet lowered the SPI compared to the Cross Creek pellet. Primed seed lots of flue-cured cultivars (NC 72 and NC 71) had a significantly higher SPI than the nonprimed seed lots at one location but not at a second location. Seed lots sown in Premier Pro-Mix TA commercial medium had a higher spiral root incidence, which resulted in a lower SPI compared to Carolina Choice, Carolina Gold, and Sunshine LP5 commercial media. The index quantitatively determined differences in seedling performance under greenhouse conditions not reflected by standard germination tests. Significant differences in the SPI were observed among seed lots with certified 90% germination. The SPI is a simple method to describe seedling performance because the data used to calculate the SPI is obtained from one seed tray image. In contrast, frequent counting and seedling evaluations are involved with standard germination and vigor tests.
- Ecology and Management of Pythium species in Float Greenhouse Tobacco Transplant ProductionZhang, Xuemei (Virginia Tech, 2021-01-07)Pythium diseases are common in the greenhouse production of tobacco transplants and can cause up to 70% seedling loss in hydroponic (float-bed) greenhouses. However, the symptoms and consequences of Pythium diseases are often variable among these greenhouses. A tobacco transplant greenhouse survey was conducted in 2017 in order to investigate the sources of this variability, especially the composition and distribution of Pythium communities within greenhouses. The survey revealed twelve Pythium species. Approximately 80% of the surveyed greenhouses harbored Pythium in at least one of four sites within the greenhouse, including the center walkway, weeds, but especially bay water and tobacco seedlings. Pythium dissotocum, followed by P. myriotylum, were the most common species. Pythium myriotylum, P. coloratum, and P. dissotocum were aggressive pathogens that suppressed seed germination and caused root rot, stunting, foliar chlorosis, and death of tobacco seedlings. Pythium aristosporum, P. porphyrae, P. torulosum, P. inflatum, P. irregulare, P. catenulatum, and a different isolate of P. dissotocum, were weak pathogens, causing root symptoms without affecting the upper part of tobacco seedlings. Pythium adhaerens, P. attrantheridium, and P. pectinolyticum did not affect tobacco seeds or seedlings. The consequences of Pythium infection were more likely to be severe when they occurred during seed germination than at seedling emergence, or after plant stem elongation when seedling roots had started to grow into underlying nutrient solutions, depending on the species of Pythium. High and low variation was observed among isolates of P. dissotocum and P. myriotylum, respectively. Pythium myriotylum co-existed with multiple other Pythium or oomycete species in the same environments within tobacco greenhouses, and significant in vitro and/or in vivo interactions between P. myriotylum and some naturally co-existing species were revealed. Pythium porphyrae may have the potential to protect tobacco seeds and seedlings from P. myriotylum infection. Greenhouse Pythium control trials identified ethaboxam, mefenoxam, and copper ionization as potentially promising alternatives to etridiazole for Pythium disease management in tobacco transplant production. The outcomes of this project provide useful new information to better understand the composition, distribution, and diversity of Pythium communities in tobacco transplant greenhouses and to improve Pythium disease management for tobacco transplant production.
- The Effect of Nematode Isolate and Soil Environment on the Tobacco cyst Nematode (Globodera tabacum solanacearum), a Pathogen of Flue-cured Tobacco and Other Solanaceous CropsRideout, Steven L. (Virginia Tech, 1998-12-02)Tobacco cyst nematodes (TCN), Globodera tabacum solanacearum, are one of the most serious pests for Virginia flue-cured tobacco (Nicotiana tabacum L.) farmers. These nematodes continue to spread to new farms every year and are now reported in 11 Virginia counties, seven North Carolina counties, and one farm in Maryland. The objectives of this study were to determine the ability of different populations of TCN to reproduce upon both a susceptible (K326) and resistant (NC567) cultivar, to compare TCN reproduction in non-infested soils with currently TCN-infested soils, and to examine reproduction and pathogenicity of TCN on other solanaceous crops. Tobacco cyst nematode reproduction on the TCN-resistant cultivar NC567 was significantly reduced when compared to the TCN-susceptible cultivar K326. Although significant differences among the populations were detected on both cultivars, the differences were not consistent across experiments. Results indicate similar pathogenicity among TCN populations on resistant and susceptible flue-cured tobacco cultivars. Plant breeders may use one population of the tobacco cyst nematode to screen tobacco germplasms for TCN resistance. Significant differences were noted in TCN reproduction among the various soils used in this study. However, the differences were inconsistent, making correlations between TCN reproduction and soil edaphic characteristics unreliable. Sterilizing the soils did not increase TCN reproduction. Reproduction in non-infested soils indicates that TCN will continue to spread throughout tobacco producing regions. Although traditionally an exclusive pest of tobacco, TCN's spread may threaten production of other solanaceous crops. Eggplant (Solanum melongena L.), pepper (Capsicum spp. L.), and tomato (Lycopersicon spp. L.) were confirmed to be hosts of TCN under field conditions. Eggplant was highly susceptible to TCN reproduction and yield suppression, exhibiting a 64% yield reduction in plots not treated with a nematicide compared to fumigated plots. Tomato allowed high rates of TCN reproduction but did not suffer yield loss. Tobacco cyst nematode reproduction was suppressed on pepper compared to the other two crops. No crop loss was noted in nontreated pepper plots compared to plots treated with a nematicide. Results would indicate that tobacco rotations including tomato or eggplant would be unacceptable due to high TCN reproduction rates. The tobacco cyst nematode does not seem to jeopardize the production of tomato and pepper in the southeastern United States, but does threaten profitability of eggplant production in this area.
- Evaluating the potential of aerial remote sensing in flue-cured tobaccoHayes, Austin Craig (Virginia Tech, 2019-06-18)Flue-cured tobacco (Nicotiana tabacum L.) is a high value-per-acre crop that is intensively managed to optimize the yield of high quality cured leaf. Aerial remote sensing, specifically unmanned aerial vehicles (UAVs), present flue-cured tobacco producers and researchers with a potential tool for scouting and crop management. A two-year study, conducted in Southside Virginia at the Southern Piedmont Agricultural Research and Extension Center and on commercial farms, assessed the potential of aerial remote sensing in flue-cured tobacco. The effort encompassed two key objectives. First, examine the use of the enhanced normalized difference vegetation index (ENDVI) for separating flue-cured tobacco varieties and nitrogen rates. Secondly, develop hyperspectral indices and/or machine learning classification models capable of detecting Phytophthora nicotianae (black shank) incidence in flue-cured tobacco. In 2017, UAV-acquired ENDVI surveys demonstrated the ability to consistently separate between flue-cured tobacco varieties and nitrogen rates from topping to harvest. In 2018, ENDVI revealed significant differences among N-rates as early as 34 days after transplanting. Two hyperspectral indices were developed to detect black shank incidence based on differences in the spectral profiles of asymptomatic flue-cured tobacco plants compared to those with black shank symptoms. Testing of the indices showed significant differences between the index values of healthy and symptomatic plants (alpha = 0.05). In addition, the indices were able to detect black shank symptoms pre-symptomatically (alpha = 0.09). Subspace linear discriminant analysis, a machine learning classification, was also used for prediction of black shank incidence with up to 85.7% classification accuracy.
- Evaluating the use of renewable fuel sources to heat flue-cured tobacco barnsBrown, Robert T. (Virginia Tech, 2018-03-23)The curing of flue-cured tobacco (Nicotiana tabacum L.) is an energy intensive process and represents a significant portion of the overall cost of production. Given the goal of the industry to reduce the environmental footprint of tobacco production and the energy demand of curing, attention has been directed to explore options for the use of renewable fuels for heating tobacco barns. A two-year study conducted at the Virginia Tech Southern Piedmont Center evaluated the effectiveness and cost of curing flue-cured tobacco with a wood pellet burner. Additionally, field studies were conducted to evaluate the feasibility of on-farm production of biomass fuel crops as well as on-farm manufacture of biomass fuel pellets. The first time use of a wood pellet burner with an air-to-air heat exchanger in a bulk curing barn proved to be a viable alternative to a conventional propane fueled burner. Curing cost averaged $0.05 with the pellet burner compared to $0.04 per kilogram of tobacco with the propane burner. The increase in cost was offset by a 90 percent reduction of CO2 emissions with the use of wood pellets. The use of low lignin grass varieties did have an impact on biomass pellet properties. Pellet testing revealed high ash and chloride levels which could be problematic using a high efficiency wood pellet burner. Full maturity harvest of annual grasses fertilized with 112 kg per ha N resulted in higher yields. However, fertilizing for maximum yield would increase the CO2 footprint for biomass fuel pellet production.
- Factors affecting the population dynamics of the green peach aphid, Myzus persicae (Sulzer), on flue-cured tobacco in VirginiaReed, T. David (Virginia Polytechnic Institute and State University, 1987)The temperature-dependent development of red and green morphs of the green peach aphid, Myzus persicae (Sulzer), was compared on flue-cured tobacco, Nicotiana tabacum (L.), at moderate to high constant temperatures in the laboratory. The red morph was found to develop faster and reproduce more than the green morph at temperatures that promoted the most rapid population growth of either morph. In addition, mean longevity of the green morph was increasingly and significantly shorter than the red morph as temperature increased above the mutual optimum temperature (25 °C) for population increase. Study of the growth of GPA populations on commercial flue-cured tobacco farms in Virginia indicated the initial GPA population is highly aggregated. As the population increases, it becomes increasingly more randomly dispersed within the field. The typical pattern of temporal development of GPA was a bimodal distribution with the greater proportion of individuals occurring after topping of the crop. Cumulative proportional population growth models using degree-days were able to adequately describe growth of populations only on individual farms. Study of the within-plant distribution of GPA found that populations developed colonies of greatest intensity on the youngest leaves. The proportion of the total GPA population found on each leaf occurring on the lower leaf surface decreased with ascending leaf position. In addition, the proportion of the total plant population found on the lower leaves was highest as the crop approached the topping stage.
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