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1. A Novel Use of Data Translation Allows 3D Prediction of Soil Fertility LandscapesSoil fertility managers need better estimates of the subsoil contribution to the nutrient pool. Thls need could be achieved through 3-D predictions of subsoil fertility using a novel method of soil- profile data translation in relation to a controlling genetic horizon. For this translation, the depth of a controlling pedogenic feature is used as the origin and the rest of the profile is linearly scaled to it. When applied to a group of soils, from across a local or regional landscape, with varyi... |
2. Aerial Photos Can Predict Corn Yield Loss Due to N DeficiencyFields that experience wet weather after N fertilizer is applied may lose N and consequently lose yield. Replacing N may be difficult or expensive after corn is too tall for tractor clearance. A tool to assess the degree of potential yield loss would help corn producers decide how much expense is justified in making late N applications. ... |
3. Arbuscular Mycorrhizal Dynamics Throughout Corn Growing SeasonPhosphorous is an essential plant nutrient and is the second most common fertilizer nutrient applied in crop production. The role of mycorrhizal fungi in phosphorous (P) nutrition of corn (Zea mays L.) in high fertility soils in unclear. A study was conducted to determine the effect of extractable P on myco~hizal biomass and to evaluate the temporal dynamics of mycorrhizal fungi during the growing season in two irrigated corn fields in Nebraska. The objectives were addressed by the installation ... |
4. Assessment of Nitrogen Supply From Poultry Manure Applied to CornThe production of poultry in the state of Iowa is one of the largest in the nation and growth has continued the past few years. Currently Iowa is the number one egg producing state in the USA (USDA, 2005). This increase in production also implies an increase in manure production from poultry sources. The common end use of manure is application for crop production. Concerns exist- regarding application at rates higher than needed for crop use, with potential for contamination of water bodies due... |
5. Balancing Agronomy and Environment: N Recommendations in Ontario for the 21st CenturyThe goal of a fertilizer program may be to maximize yields from each ficld, or to maximize profit, or to minimize environmental impact. Recent instances of groundwater contamination with nitrate have focused attention on the need for source water protection, and agriculture has been implicated as one of the sources of nitrate contamination. This has lead to concerns that environmental rules could reduce the profitability of crop production, by limiting fertilizer use and hence, crop yields. Addi... |
6. Determining Economic Optimum Nitrogen Rates with the Illinois Soil Nitrogen Test and Soil Organic Nitrogen FractionsDevelopment of a diagnostic test to estimate soil N supplying capability is a continuing research need. The Illinois soil nitrogen test (ISNT) has been proposed as a method for adjusting corn (Zea Mays L.) N recommendations for to account for soil organic N contributions. We evaluated the ISNT as a tool for predicting corn N response in Wisconsin by comparing ISNT values and corn N response data from-81 experiments conducted between 1984 and 2004 with a range of crop rotations, management histo... |
7. Effect of Timing of Broadcast Potassium (K) on Soybean Yield and Seed K ContentIn Indiana, the common practice is for K fertilizer to be applied in advance of the corn crop for both crops in the rotation, relegating soybean to feed on the application residual. Producers are concerned that current University guidelines and common practices for K management in corn- soybean rotations do not fully recognize the particular K needs of the soybean crop as differentiated from the corn crop. A four-location, six-year field study was conducted to investigate the effects of rate and... |
8. Evaluation of Slow Release Nitrogen Materials in Corn ProductionStudies were conducted over a two year period to evaluate two slow release urea nitrogen carriers with regular urea for the production of corn on iirigated Spinks loamy sand. Because nitrogen availability in the soil is quite transient fiom one season to the next, annual addition of nitrogen is important for maximu~n corn yields. Many corn producers prefer to apply most of the nitrogen prior to planting corn. Once incorporated into the soil, nitrogen containing materials, such as urea, are conve... |
9. Fertilizer Nitrogen Source and Management Impacts on Greenhouse Gas EmissionsAgricultural soil management accounts for nearly 6.3% of all greenhouse gas emission in the U.S. Although fertilizer nitrogen is an essential coinponent of nearly all agricultural systems, the addition of reactive N to soils and the emission of nitrous oxide (N20) via soil microbiological processes (nitrification and denitrification) makes U.S. agriculture the largest source (62%) of total U.S. N20 emissions. Because N20 is a potent greenhouse gas with a forcing potential more than 300 times gre... |
10. Hybrid Maize A Simulation Model for Improving Corn ManagementHybrid-Maize (www.hybridmaize.unl.edu) is a computer program that simulates the growth and yield of a corn crop under non-limiting or water-limited (rainfed or irrigated) conditions. The model can be used to (1) assess the overall site yield potential and its variability based on historical weather data, (2) evaluate changes in attainable yield using different combinations of planting date, hybrid maturity and plant density, (3) analyze yield in relation to silking and maturity in a specific yea... |
11. Impact of Nitrogen and Sulfur Fertilization on Wheat Yield and QualitySulfur (S) contributed by rainfall has decreased by 50% over the last twenty-seven years and may increase the need for S supplementation by fertilization. Nitrogen (N) application is typically split applied in Ohio with some applied in the fall and remainder applied in the spring near first green-up. The objective of this study was to compare N application source and timing with and without S fertilization. Two experimental locations were established in the fall of 2004. Urea and urea-ammonium n... |
12. Impact of Stratified Potassium and Water Content of No-Till Soils on Soybean Growth and YieldLow potassium (K) concentrations in subsurface soil and reduced water content in the K- enriched surface soil are thought to cause K-related yield reductions in rain-fed soybean (Glycine max L. Merr.). Our objectives were to examine root-to-shoot ratios through ontogeny and yield components in relation to stratified soil water and K. Soil and plant samples were collected at V6, R2, R4, and R6 from a 2-year field study. Additionally, a greenhouse split-root ot study in P a complete factorial des... |
13. Improving the Fermentation Characteristics of Corn Through Optimum Fertilization and Hybrid SelectionEthanol processors could increase production efficiency if they had access to corn grain better- suited for fermentation. The objective of this study was to determine the influence of hybrids and N fertility rates on fermentable starch content that will be used for dry-mill ethanol production. Six hybrids were grown under four N fertility levels at two locations in eastern SD. Ethanol yields increased as N fertility levels increased. Higher ethanol yields were achieved by hybrids that produced b... |
14. In Season RecommendationsWe are testing a prototype high-clearance tractor configured with active crop canopy sensors, drop nozzles with electronic valves, and a variable rate controller as means to deliver in-season variable rates of liquid N fertilizer based on crop needs as an alterative to preplant uniform applications of N. The active sensor we're evaluating is the model ACS-210 Crop Circle made by Holland Scientific. It generates it's own source of modulated light in the amber and near infrared (NIR) bands and the... |
15. Introgressing Unique Sources of Germplasm to Improve N Use in Temperate MaizeThe vast majority of maize breeding efforts have been conducted under high N environments that primarily select for only one component of NUE, N uptake. Furthermore, these studies have employed US. and European genotypes, which have been selected for performance at high N. Historically, maize was grown in numerous low N tropical environments, suggesting that evaluation of adapted maize lines containing tropical germplasm may harbor useful genetic variation and novel alleles for improving NUE. Th... |
16. Long Term Outlook On Nitrogen and Potassium SupplyThe North American fertilizer industry is operating in world market today. Worldwide fertilizer demand, competition for transportation, and natural gas prices are all putting pressure on North American fertilizer prices. The themc of this mornings' session is on strategies the supply industry and fanners may adopt to manage these pressures. This talk is about the near future outlook nitrogen and potassium fertilizer. Fertilizer sales figures indicate that nitrogen, phosphorus. and potassium fer... |
17. Making Urea Work in No TillNo-till and reduced tillage production systen~s are widely used today in the United States as well as around the world due to their capacity for reducing soil erosion and topsoil loss, reducing phosphorus movement to surface water, and reducing labor, fuel, and equipment requirements. In no-till systems, an average of 25% of the N applied as broadcast urea can be lost via ammonia volatilization. Therefore, N losses due to ammonia volatilization will decrease corn and wheat yields. independently ... |
18. Managing Continuous Corn for High YieldsMany "contest-winning" corn yields have historically been produced in fields where corn is grown continuously, often with extensive tillage, hgh soil test values of P and K, high N rates, and high plant populations. We are conducting a series of research trials at four sites in Illinois, in whlch we are varying tillage, fertilizer rates, and plant population in a factorial experiment at several Illinois locations. Over ten site-years to date, tillage deeper than normal increased yield at two sit... |
19. Near Seed Application of Fluid Fertilizer for Corn Soybean and Sugarbeet ProductionIn recent years, crop producers in Minnesota have shown increased interest in placing fertilizer near the seed at planting. The more traditional 2x2 "starter" band was not an option. Guidelines were needed for banded placement of fertilizer near the seed at the time of planting. This study was conducted in 2004 and 2005 in fields of cooperating crop producers. Three fluid . materials (10-34-0, 4-10-10, 3-18-18) were applied at two rates for corn, soybeans and sugarbeets. In 2004, the materials w... |
20. Opportunities and Limitations of Automatic Steering TechnologiesIn the short span of 10 years we have gone from using the Global Positioning System (GPS) to locate ourselves in a farm field, to automatically steering a machine working in the field. This application requires about 15 conlponents with each component evolving at a rapid pace. A number of conlpanies have formed to provide automatic steering packages as aftermarket retrofits. At a slightly slower pace, the main equipment manufactures are engineering machines that will be factor ready or factory e... |
21. Phosphorus and Potassium Place in Corn-Soybean Systems in the Midwest: Possibilities with Automatic Guidance TechnologyGlobal positioning system teclmology available to the public has become more accurate in recent years. Current Real Time Kinematic (RTK) techniques allow relative positions of equipment to be recorded with 3/8 - 2 in. precision (Dana, 1991). Being able to return to the same location in the field year after year with high precision may have implications for corn-soybean systems where banded applications of phosphorus (P) and/or potassium (K) are made at a time other than at planting. The importan... |
22. Regional Approach to Making Nitrogen Fertilizer Rate Decisions for CornNitrogen fertilizer is one of the largest input costs for growing corn. Across the Corn Belt, N is typically the most yield-limiting nutrient. Facing record high N fertilizer prices and potential supply problems, producers are concellled about N fertilization rates. Soil fertility researchers and extension specialists froin seven states across the Corn Belt (see list in acknowledgements section) have been discussing corn N fertilization needs and evaluating N rate recommendation systems for appr... |
23. Scale of Measurement Effects on Phosphorus Runoff Losses from CroplandAs phosphorus (P)-based nutrient management planning becomes necessary for some farms in Wisconsin, it will be critical to have reliable, research-based planning tools. The Wisconsin P- hdex provides one method for preparing P-based nutrient management plans. The P-Index was developed largely from small plot-scale data showing the relationships between various site and management variables and runoff P losses. Thls study was conducted to compare runoff composition measurements at the subwatershe... |
24. Slow Release Nitrogen Fertilizer and Dynamics in Soil Systems Part I Incubation StudyA lab study was conducted at Southern Illinois University soil fertility research facility to investigate the effects of soil type on the nitrogen (N) release dynamics. The objective of this study was to identify the effect of soil type on the release rate of N from slow release nitrogen (SRN) fertilizers under controlled conditions (moisture and temperature). Two contrasting soils from Iowa and Georgia (pH and mineralogy) were combined with 500 mg kg-, of SRN or urea and kept for 90 days under ... |
25. Strip Tillage and No Tillage Fertilization Systems Evaluated for Eastern Kansas Rain Fed CornRow-crop agriculture in East-Central and Southeast Kansas is facing increasing pressure to reduce sediment and nutrient losses via runoff. Edge-of-field measurements show that no-tillage with fertilizers placed below the surface of the soil has significantly less sediment and total P losses in runoff compared to conventional tillage (Janssen et al., 2000). However, for rain-fed corn, no-tillage in these regions can provide serious challenges some years because of frequent spring rains and an abu... |
26. Study on Phosphorus and Nitrogen Concentration of Corn Adapted in South DakotaThough nitrogen (N) and phosphorus (P) are vital in several physiological and developmental processes in plants and animals, they pose several environmental, nutritional and health problems, if present in excess amounts. Reduction in the excess input of these nutrients into the soil, thereby reducing environmental problem and consequently nutritional and health problem, can be achieved by balancing their concentration in animal feed. Therefore, this research aims to quantify the nitrogen and pho... |
27. Swine Manure Phosphorus Use for Crop Production in IowaImproving manure phosphorus (P) management guidelines should result in a more efficient use of thls resource for crop production and in lower risk of P loss to surface water resources. Phosphorus fertilizers are widely used in crop production, there is a great deal of information about their use, and farmers have little doubt about their value to improve crop yield in low- testing soils. However, there is a great deal of uncertainty concerning the value of manure nutrients for crops and about co... |
28. The Influence of Nitrogen Rate and Foliar Fetilization on Yield and Nitrosamine Levels in Burley TobaccoMany burley tobacco (Nicotiana tabactm~ L.) producers believe that additions of nitrogen (N) rates greater than those recommended by university extension senices will result in increased yield and income. In addition to high rates of N, many producers feel that additional foliar fertilizer will further increase yield and quality of burley tobacco and result in greater revenue. Concerns with excessive N additions include improper curing, elevated levels of tobacco specific nitrosamines (TSNA's), ... |
29. Validating the Wisconsin P Index with Measured Runoff P Losses From Agricultural FieldsPhosphorus (P) indices have been developed by most states in the USA for use as planning tools to assess the risk of P loss and identify appropriate management alternatives to control these losses where needed. Little information is available on the relationshp between P index values and actual P runoff losses in the field. We compared annual P losses in runoff measured at 2 1 field or sub-watershed locations with Wisconsin P index values calculated for the same areas. The research sites include... |
30. Zone Delineation for Nitrogen ManagementManaging nitrogen through zone soil sampling has been shown effective in revealing residual soil nitrate patterns in North Dakota. Zone delineation has been constructed using several types of data, including yield maps, remote imagery, topography and soil EC sensor data. A study was conducted in North Dakota, Montana and Minnesota to evaluate zone delineation methods. Across the region, yield frequency maps, topography, remote inlagery and soil EC data were effective in helping to construct zon... |