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Showing 1 to 20 of 122 for “"N fertilizer"”.
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Agronomic and marker-assisted breeding strategies for improving nitrogen use efficiency in maize
… sustainable agricultural practices with less N fertilizer inputs. Improved nitrogen use efficiency (NUE) can maximize maize yield with minimal inputs of N fertilizer, but requires coordinated progress in several areas of the crop’s production (e.g. genetic improvement, genetic characterization, …
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Optimizing soil and fertilizer nitrogen use by intensively managed soft red winter wheat
… experiments consisted of varying amounts of N fertilizer rates applied at Zadoks' growth stages 25 (GS 25) and 30 (GS 30). The research was divided into three studies. The first study was conducted to assess the effect of N fertilizer rates and climatic conditions on the amounts and patterns of …
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Investigating best management practices to reduce selenium and nitrate contamination in a regional scale irrigated agricultural groundwater system: Lower Arkansas River Valley, southeastern Colorado
… reduction in the seasonal application of N fertilizer; decrease in concentration of selenate (CSeO4) and nitrate (CNO3) in canal water, representing treatment of water before application as irrigation water; reduction in irrigation application volumes; and combinations of these practices, …
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Effects of Nitrogen and Potassium Fertilizer on Willamette Spider Mite (Eotetranychus willamettei) (Acari: Tetranychidae)
… stages of plant growth. Amending soils with fertilizer is a common cultural practice used in commercial vineyards, but no study has documented the interaction between the effects fertilizer concentrations have on Willamette spider mite. This project consisted of a field study (at Cambria …
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Recovery of Nitrogen-15-Labeled Liquid Anhydrous Ammonia Applied to Soil
… (LAA) is the most extensively used nitrogen (N) fertilizer in U.S. and Illinois agriculture, knowledge concerning its transformations in soil is limited. The understanding of LAA transformations and the products it forms in soil are agronomically important because they ultimately determine the …
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Nitrogen Acquisition of Pea-Oat and Pea-Canola Intercrops and Their Impact on Subsequent Wheat Crops
… of the intercrops were supplied with three N fertilizer rates (0, ¼, ½ of their recommended rate), while the monocrops (pea, oat, canola) received their full recommendation of N fertilizer, except pea which received no N fertilizer. In the following year, wheat was supplied with its full …
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Estimating Soil Nitrogen Supply and Fertilizer Needs for Short-Rotation Woody Crops
… nutrition response to repeated nitrogen (N) fertilizer applications, 2) determine soil N supply, plant N demand, foliar N resorption, and soil and fertilizer uptake efficiencies, and 3) test a simple N supply model. In order to expand the findings to the range of sweetgum site types, the …
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Development of Nitrogen rate Recommendations for No-till Dryland Grain Sorghum in Virginia
… mid-Atlantic region to develop full-season N fertilizer recommendations for dryland no-tillage grain sorghum (Sorghum bicolor L. Moench) production. The objectives of this study were: (i) to determine the optimum rate of band-placed starter N fertilizer needed in combination with side-dress N …
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Validation of N-STaR Nitrogen Rate Recommendations and Evaluation of N-STaR Soil Sampling Procedures for Clay Soils in Arkansas
<p>The two methods for determining N-fertilizer recommendations for rice (Oryza sativa L.) in Arkansas are the standard N recommendation (SR) based on soil texture, previous crop, and rice cultivar, and the Nitrogen-Soil Test for Rice (N-STaR) which quantifies the potentially mineralizable-N of the …
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Miscanthus X Giganteus Production: Meta-Analysis, Field Study and Mathematical Modeling
… season, planting density and nitrogen (N) fertilizer but also provided a measure of uncertainty about these effects. More importantly, it provided statistical models which are essentially testable hypotheses. These models were used in Chapter 2 to predict dry biomass considering effects of …
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Time And Rate Of Nitrogen Fertilization Influence Maize Nitrogen Use Efficiency And Soil Enzyme Activity
… to maize in 2014 to 2016. At Becker, applying N fertilizer at the recommended rate as a three-way split improved maize grain and biomass yield, maize nutrient uptake, and nitrogen use efficiency (NUE). At Lamberton, grain yield, nutrient uptake, and NUE parameters did not differ among treatments …
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Assessment of Spectral Reflectance as Part of a Variable-Rate Nitrogen Management Strategy for Corn
… has been used to adjust in-season nitrogen (N) fertilizer rates for wheat to account for spatial variability in grain yield potential at a sub-meter resolution. The objective of this study was to examine the relationships among spectral reflectance indices, corn tissue N content, chlorophyll …
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Evaluation of nitrogen availability indices
… and environmental concerns dictate that N fertilizer be applied to optimize crop production and minimize potential for movement of N into surface and/or ground water resources. Field and laboratory studies were conducted to evaluate factors affecting the reliability of recommendations from …
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Nitrogen and phosphorus fertilization for efficient corn production in Virginia
… com fertilization methods of broadcasting N fertilizer, and applying P fertilizer to soils testing high to very high in plant-available P, can be inefficent. Experiments were conducted at several locations in Virginia to evaluate if band applications of N fertilizer are more efficient than …
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The Impact of Selected Forage Legumes on Cattle Performance, Forage Production, and Soil Quality, and Evaluation of Legume Persistence under Grazing
<p>Interest in substituting legumes for N fertilizer in beef cattle grazing systems has recently increased with rising fertilizer prices. Legumes are well known for their ability to fix atmospheric N and decrease dependence on input of N fertilizer. However, there are still difficulties associated …
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Symbiotic N² fixation in cyclopia vent. spp. (honeybush) : towards sustainable cultivation in the Western Cape of South Africa
… tea yields without the need for chemical fertilizers, promoting the crop's status as an organically farmed health product, limiting the environmental degradation associated with N fertilizer use and benefiting small-scale farmers in the region who cannot afford chemical fertilizers.
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Minimizing the continuous maize penalty through intense management
… maize yields when used individually (e.g. fertilizer application, genetically-engineered traits, crop rotation). Some management practices have been shown to produce greater-than-additive yield effects when combined (e.g. fertilization and irrigation; increased plant population and …
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Balancing water quality, nitrogen management, and corn production goals in Illinois
Nitrogen (N) fertilizer inputs are required to maintain corn production in high-yielding cropping systems across much of the U.S. Midwest. However, applied N can also increase N losses through nitrate-nitrogen (NO3-N) leaching and nitrous oxide (N2O) emissions, negatively impacting water and air …
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Greenhouse gas emissions from production of Miscanthus x giganteus on a Mollisol
… to maximize productivity, but the amount of N fertilizer Miscanthus x giganteus might need is currently not known. Because M. x giganteus is highly efficient in its N use, it is a great potential energy crop because it has had large yields even at low N inputs from fertilizers (including no …
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Intercropping Studies With Soybean (Glycine Max (L.); Merr.) and Maize (Zea Mays L.) or Ryegrass (Lolium Perenne L.)
This research concentrates on the study of N fertilizer, N$\sb2$-fixation, and N-transfer under monocrop and intercrop conditions and on the amount of residual soil N after intercrop and monocrop systems. In the experiments reported here, soybean (Glycine max (L.) Merr.) was grown in association …
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