Browsing by Author "Holshouser, David L."

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    2009-2010 Performance of Sorghum Hybrids in the Virginia-Carolina Region
    Balota, Maria; Holshouser, David L.; Dahlberg, Jeff; Padgett, Shelee (Virginia Cooperative Extension, 2011)
    This report presents 2009-2010 crop data for Sorghum varieties in North Carolina and Virginia, including data on planting and harvest dates, soil type, irrigation, weed management, nutrient management, pest and disease control, and weather conditions
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    2009-2011 Performance of Sorghum Hybrids in the Virginia-Carolina Region
    Balota, Maria; Herbert, D. Ames Jr.; Holshouser, David L.; Dahlberg, Jeff (Virginia Cooperative Extension, 2013)
    This report presents 2009-2011 crop data for Sorghum varieties in North Carolina and Virginia, including data on planting and harvest dates, soil type, irrigation, weed management, nutrient management, pest and disease control, and weather conditions
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    2015 Virginia OnFarm Soybean Test Plots
    Balderson, T. Keith; Broaddus, Mike; Clarke, Taylor; Deitch, Ursula; Flanagan, Roy; Hopkins, Steve; Jones, Bruce; Jones, Trent; Lawrence, Watson; Long, Theresa; Moore, David M.; Norton, Nikki; O'Keefe, Christine; Reiter, J. Scott; Romelczyk, Stephanie; Siegle, Laura; Slade, Glenn; Tucker, Lindy; Holshouser, David L. (2016-01-25)
    These demonstration and research plot results are a collaborative effort of Virginia Cooperative Extension (VCE) Agents and Specialists, area producers, and agribusiness. The purpose of this publication is to provide research based information to aid in the decision making process for soybean producers in Virginia. It provides an unbiased evaluation of varieties, management practices, and new technologies through on farm replicated research using producer equipment and time. These experiments enable producers to make better management decisions based on research and provide greater opportunities to improve yields and profits, which improves quality of life for them and their families.
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    2019 Virginia On-Farm Soybean Research
    Reiter, Scott; Romelczyk, Stephanie; Broaddus, Mike; Clarke, Taylor; Fimon, Lindy; Flanagan, Roy; Holland, Josh; Jones, Bruce; Jones, Trent; Lawrence, Watson; Longest, Robbie; Parrish, Michael J.; Rutherford, Sara; Siegle, Laura; Stafford, Carl; Holshouser, David L. (Virginia Cooperative Extension, 2019)
    Discusses data collected from soybean test plots in 2019, including variety selection, fungicides, maturity and development of plants, seed treatments, and tillage systems.
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    Agronomic and Economic Comparison of Full-Season and Double-Cropped Small Grain and Soybean Systems in the Mid-Atlantic USA
    Browning, Phillip W. (Virginia Tech, 2011-05-02)
    Increased demand for barley has changed the proportion of crops grown in Virginia and the Mid-Atlantic USA. Winter wheat is the predominant small grain crop, but barley can be a direct substitute, although much less of it is grown. Soybean is grown full-season and double-cropped after both small grains. Historically, wheat was the primary small grain in the soybean double-crop rotation because of its greater profitability. The barley-soybean cropping system is not a new concept in the region, but the literature is outdated. New agronomic and economic data that directly compares full-season soybean, barley-soybean, and wheat-soybean systems using modern cultivars and management practices is needed. The objectives of this research were to: i) determine soybean yield and compare cropping system profitability of the three cropping systems; ii) perform a breakeven sensitivity analysis of the three cropping systems; and iii) determine the effect of planting date and previous winter crop on soybean yield and yield components. Soybean grown after barley yielded more than full-season soybean in two of six locations and more than soybean double-cropped after wheat in three of six locations. Net returns for the barley-soybean system were the greatest. These data indicate that soybean double-cropped after barley has the potential to yield equal to or greater than full-season soybean or double-cropped soybean following wheat, but its relative yield is very dependent on growing conditions. The profitability comparison indicated that the barley-soybean cropping system was generally more profitable than the full-season soybean and double-cropped wheat-soybean systems. This conclusion was supported by the breakeven sensitivity analysis, but remains dependent on prices that have been extremely volatile in recent years. In another study, soybean yields declined with planting date at two of four locations in 2009, a year that late-season rainfall enabled later-planted soybean to yield more than expected. In 2010, soybean yield decline was affected by the delay in planting date at both locations. Winter grain did not affect soybean yield in either year. Yield component data reinforced these results and indicated that the lower seed yield in the later planting dates was due primarily to a decrease in the number of pods.
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    Agronomy Handbook
    Brann, Daniel Edward; Abaye, Azenegashe Ozzie; Peterson, Paul R.; Chalmers, David R.; Whitt, David L.; Chappell, Glenn F.; Herbert, D. Ames Jr.; McNeill, Sam; Baker, James C.; Donohue, Stephen J.; Alley, Marcus M.; Evanylo, Gregory K.; Mullins, Gregory L.; Hagood, Edward Scott; Stallings, Charles C.; Umberger, Steven H.; Swann, Charles W.; Reed, David T.; Holshouser, David L. (Virginia Cooperative Extension, 2009-05-01)
    Provides readers with a source of agronomic information such as field crops, turfgrasses, variety selection, seed science, soil management, nutrient management and soil suitability for urban purposes that does not change frequently - pesticide and varietal information changes frequently and is therefor not included.
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    Alternative and Improved Cropping Systems for Virginia
    Chim, Bee Khim (Virginia Tech, 2016-04-27)
    Feed grain consumption in Virginia and the mid-Atlantic region is more than double the total production. Producing more feed grains in this region could generate more profit for grain growers and lower costs for end-users. Increased feed grain production in this region will necessitate improved corn (Zea mays L.) management techniques and adoption of alternative feed grains such as grain sorghum (Sorghum bicolor L.). In order to achieve our overall objective of increased corn and grain sorghum production in the region, experiments were conducted to assess tools with the ability to increase the efficiency of sidedress nitrogen (N) application for corn and to test the performance of grain sorghum in both full season and double-crop rotations in this region. For the corn studies, seven field experiments were established in 2012-2014 with four replications in a randomized complete block design. Treatments included a complete factorial of four different preplant N rate (0, 45, 90, 134 kg ha-1) with three different approach simulation model-prescribed rates (Virginia Corn Algorithm, Maize-N, Nutrient Expert-Maize) and the standard Virginia yield-goal based approach. No differences in corn yield were found between the different simulation model and preplant N rate, however the prescribed sidedress N rate varied significantly due to the simulation model, preplant N rate and the interaction between them. The nitrogen use efficiency (NUE) was estimated based on partial factor productivity (PFP) of nitrogen. The greatest PFP resulted from use of the Virginia Corn Algorithm (VCA), which produced 68 kg grain kg N-1 compared with 49 kg grain kg N-1 for the yield-goal based approach. While the VCA shows promise as a tool for improving NUE of sidedress applications in corn, more research is needed to validate performance. Soybean (Glycine max L.) is often double-cropped after small grain in the mid-Atlantic region. Growing grain sorghum in this niche in the cropping system instead could result in greater overall feed grain production. In order to assess the performance of grain sorghum as an alternative in common cropping systems, four field experiments were established at the Southern Piedmont Agriculture Research and Extension Center (SPAREC) and Tidewater Agriculture Research and Extension Center (TAREC), near Blackstone and Holland, Virginia, respectively. The experiments were conducted using a split plot design with four replications and fourteen treatments. Main plot was winter small grain crop; either barley (Hordeum vulgare L.), triticale (x Triticosecale.), wheat (Triticum aetivum L.) or winter-fallow and the subplot either soybean or sorghum. In three of four instances, full season sorghum yields were greater than double-cropped sorghum after small grain. At two locations, sorghum yields following triticale were lower than when following barley, possibly indicating an antagonistic or allelopathic effect of triticale. The most profitable cropping system was wheat-soybean based on the price assumptions and measure yields in this experiment. Among the sorghum cropping system, the most profitable system was also wheat-sorghum. Sorghum can be successfully grown in both full-season and double-crop systems and offers good potential to increase feed grain production in this region.
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    Asian Soybean Rust--Frequently Asked Questions I: Background and General Information
    Bush, Elizabeth A.; Stromberg, Erik L.; Phipps, Patrick Michael; Holshouser, David L. (Virginia Cooperative Extension, 2009)
    Provides general information on Asian Soybean Rust (Phakospora pachyrhizi) and its potential impact on soybean crops in Virginia.
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    Asian Soybean Rust--Frequently Asked Questions II: Background and General Information
    Stromberg, Erik L.; Bush, Elizabeth A.; Holshouser, David L.; Phipps, Patrick Michael (Virginia Cooperative Extension, 2009)
    Describes Asian Soybean Rust (Phakospora pachirhizi) and its damage to soybean plants.
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    Asian Soybean Rust--Frequently Asked Questions III: Background and General Information
    Phipps, Patrick Michael; Stromberg, Erik L.; Holshouser, David L.; Bush, Elizabeth A. (Virginia Cooperative Extension, 2009)
    Provides information about treating soybean plants with fungicides to control Asian Soybean Rust (Phakospora pachirhizi).
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    Asian Soybean Rust--Frequently Asked Questions IV: Background and General Information
    Holshouser, David L.; Phipps, Patrick Michael; Stromberg, Erik L.; Bush, Elizabeth A. (Virginia Cooperative Extension, 2009)
    Discusses planting methods for soybean crops in relation to Asian Soybean Rust (Phakospora pachirhizi).
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    Asian Soybean Rust--Frequently Asked Questions V: Background and General Information
    Holshouser, David L.; Bush, Elizabeth A.; Phipps, Patrick Michael; Stromberg, Erik L. (Virginia Cooperative Extension, 2009)
    Discusses methods and importance of monitoring soybean fields for Asian Soybean Rust (Phakospora pachirhizi).
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    Asian Soybean Rust--Frequently Asked Questions VI: Background and General Information
    Grisso, Robert D.; Holshouser, David L.; Bush, Elizabeth A.; Phipps, Patrick Michael; Stromberg, Erik L. (Virginia Cooperative Extension, 2009)
    Discusses the sprayer and nozzle technology for use in soybean fields that have or are at risk for Asian Soybean Rust (Phakospora pachirhizi.
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    Assessing Genetic and Environmental Influence on Traits Associated with Natto Quality
    Cook, David E. (Virginia Tech, 2008-05-08)
    Food grade soybean production is a high value alternative to conventional soybean use. The production of natto, a fermented soyfood, requires soybean cultivars that consistently express specific quality traits over a range of growing environments. Therefore, it is necessary to evaluate genetic and environmental influence for natto quality traits to ensure consistent performance. A multi location experiment was conducted in 2006 and 2007 to address the influence of soybean cropping system (double crop vs. full season) and environmental factors on traits associated with natto quality. Two statistical models were used to analyze the effects of planting system and environment on agronomic traits such as yield, maturity, and seed size and natto quality traits such as water absorption, water loss after steaming, seed coat deficiency, and rate of water absorption. Genotype variation was significant for all traits, but genetic differences for water loss after steaming were minimal. Planting system significantly influenced all natto quality traits. Seed coat deficiency and rate of water absorption displayed the most differential response and double crop plantings produced superior characteristics. Genotype à environment interactions were significant for all traits, but they did not confound selecting superior natto cultivars. Significant environment and year effects indicate environmental sensitivity, but genotype rankings rarely changed. The results indicate that genotype was the most important factor controlling the natto quality traits tested. These results suggest breeding for superior natto cultivars is possible but environmental influence must be accounted for and multi environment testing is necessary for genotype natto quality evaluation.
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    Assessment of Soybean Leaf Area for Redefining Management Strategies for Leaf-Feeding Insects
    Malone, Sean M. (Virginia Tech, 2001-08-31)
    Commercially available leaf area index (LAI) meters are tools that can be used in making insect management decisions. However, proper technique must be determined for LAI estimation, and accuracy must be validated for the meters. Full-season soybean require LAI values of at least 3.5 to 4.0 by early to mid-reproductive developmental stages to achieve maximum yield potential, but the relationship between double-crop soybean LAI and yield is unknown. This research (1) evaluated minimum plot size requirements for mechanically defoliated soybean experiments using the LAI-2000 Plant Canopy Analyzer, (2) compared LAI estimates among LAI-2000 detector types which respond to different wavelengths of light, (3) compared LAI-2000 estimates with directly determined LAI values for 0, 33, 66, and 100% mechanical defoliation levels, (4) used linear and non-linear models to describe the response of full-season and double-crop soybean yields to reductions in LAI through mechanical defoliation, and (5) evaluated the response of double-crop soybean yields to reductions in LAI through insect defoliation. The minimum plot size for obtaining accurate LAI estimates of defoliated canopies in soybean with 91 cm row centers is four rows by 2 m, with an additional 1 m at the ends of the two middle rows also defoliated. The wide-blue detector, which is found in newer LAI-2000 units and responds to wavelengths of light from 360 to 460 nm, gave higher LAI estimates than the narrow-blue detector, which responds to light from 400 to 490 nm. The unit with the narrow-blue detector gave estimates equal to directly determined LAI in two of three years for 0, 33, and 66% defoliation levels, while the units with the wide-blue detectors gave estimates higher than directly determined LAI in the two years that they were studied, except for a few accurate 33% defoliation estimates. Therefore, the LAI-2000 usually provides reasonable estimates of LAI. Yield decreased linearly with LAI when LAI values were below 3.5 to 4.0 by developmental stages R4 to R5 in both full-season and double-crop soybean. Usually, there was no relationship between yield and LAI at LAI values greater than 4.0. There was an average yield reduction of 820 ± 262 kg ha⁻¹ for each unit decrease in LAI below the critical 3.5 to 4.0 level; maximum yields ranged from 1909 to 3797 kg ha⁻¹. Insect defoliators did not defoliate double-crop soybean plots to LAI levels less than 4.0, and there was no yield difference between insect-defoliated and control plots. Therefore, double-crop soybean that maintains LAI values above the 3.5 to 4.0 critical level during mid-reproductive developmental stages is capable of tolerating defoliating pest
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    Average Relative Yields of Soybean Tested in the Virginia Official Variety Test 2008-2010
    Holshouser, David L. (Virginia Cooperative Extension, 2011-01-25)
    Selecting high-yielding soybean varieties is one of the most important steps for profitable production. To help with variety selection, Virginia Tech conducts full-season and double-crop variety tests in five regions of Virginia. Data presented in this publication is an average taken from multiple-locations over the past three growing seasons.
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    Average Relative Yields of Soybean Tested in the Virginia Official Variety Test, 2009-2011
    Holshouser, David L. (Virginia Cooperative Extension, 2012-03-22)
    Discusses crop yield for soybeans grown in Virginia from 2009 to 2011.
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    Average Relative Yields of Soybean Tested in the Virginia Official Variety Test, 2010-2012
    Holshouser, David L. (Virginia Cooperative Extension, 2013-03-01)
    Discusses crop yield for soybeans grown in Virginia from 2010 to 2012.
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    Average Relative Yields of Soybean Varieties Tested in the Virginia Official Variety Test, 2007-2009
    Holshouser, David L. (Virginia Cooperative Extension, 2010-04-20)
    Selecting high-yielding soybean varieties is one of the most important steps for profitable production. To help with variety selection, Virginia Tech conducts full-season and double-crop variety tests in five regions of Virginia. Data presented in this publication is an average taken from multiple-locations over the past three growing seasons and includes varieties that have been tested in the last two years.
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    Control and Fecundity of Palmer Amaranth (Amaranthus palmeri) and Common Ragweed (Ambrosia artemisiifolia) from Soybean Herbicides Applied at Various Growth and Development Stages
    Scruggs, Eric Brandon (Virginia Tech, 2020-05-18)
    Palmer amaranth (Amaranthus palmeri) and common ragweed (Ambrosia artemisiifolia) are two of the most troublesome weeds in soybean. Both weeds possess widespread resistance to glyphosate and acetolactate synthase (ALS) inhibiting herbicides resulting in the use of protoporphyrinogen oxidase- (PPO) inhibitors to control these biotypes, although PPO-resistant biotypes are increasing. New soybean herbicide-resistant trait technologies enable novel herbicide combinations. Combinations of two herbicide sites-of-action (SOA) improved control 19 to 25% and 14 to 19% of Palmer amaranth and common ragweed, respectively, versus using one SOA (mesotrione, dicamba, 2,4-D, or glufosinate alone). Seed production of 5 to 10 cm Palmer amaranth and common ragweed was reduced greater than 76% by fomesafen, auxin (dicamba and 2,4-D), or glufosinate containing treatments. Some weeds survived and set seed even when treated at the proper size. As weed size increased from 10 to 30 cm, control diminished and fecundity increased, underscoring the importance of proper herbicide application timing. Effective preemergence herbicides reduced the number of weeds present at the postemergence application compared to no treatment, reducing the likelihood of herbicide resistance development. Dicamba, 2,4-D, or glufosinate applied alone or auxin + glufosinate combinations reduced Palmer amaranth seed production greater than 95% when applied at first visible female inflorescence; this first report, in addition to previous reports on individual herbicides, indicates this application timing may be useful for soil seed bank management. This research informs mitigation of herbicide resistance spread and development.