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United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
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Articles 1 - 30 of 54
Full-Text Articles in Life Sciences
Handbook Of Plant And Crop Physiology, Second Edition, Revised And Expanded, Wally Wilhelm
Handbook Of Plant And Crop Physiology, Second Edition, Revised And Expanded, Wally Wilhelm
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
This book, as the title states, is an updated and expanded edition of a 1995 book with a similar title and the same editor. The first thing that may strike the reader of the Handbook is the physical size of this volume. Although the second edition is a few pages shorter than the original (973 vs. 1003 pages), the print size was reduced in this revised edition allowing the expanded text to be presented in a similar number of pages. In revising the book, the editor and authors have rearranged the sections, updated almost all chapters, and added chapters on …
Prevalence And Characterization Of Non-O157 Shiga Toxin-Producing Escherichia Coli On Carcasses In Commercial Beef Cattle Processing Plants, Terrance M. Arthur, Genevieve A. Barkocy-Gallagher, Mildred Rivera-Betancourt, Mohammad Koohmaraie
Prevalence And Characterization Of Non-O157 Shiga Toxin-Producing Escherichia Coli On Carcasses In Commercial Beef Cattle Processing Plants, Terrance M. Arthur, Genevieve A. Barkocy-Gallagher, Mildred Rivera-Betancourt, Mohammad Koohmaraie
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Beef carcass sponge samples collected from July to August 1999 at four large processing plants in the United States were surveyed for the presence of non-O157 Shiga toxin-producing Escherichia coli (STEC). Twenty-eight (93%) of 30 single-source lots surveyed included at least one sample containing non-O157 STEC. Of 334 carcasses sampled prior to evisceration, 180 (54%) were found to harbor non-O157 STEC. Non-O157 STEC isolates were also recovered from 27 (8%) of 326 carcasses sampled after the application of antimicrobial interventions. Altogether, 361 non-O157 STEC isolates, comprising 41 different O serogroups, were recovered. O serogroups that previously have been associated with …
Nitrogen And Dry Matter Distribution By Culm And Leaf Position At Two Stages Of Vegetative Growth In Winter Wheat, Wally Wilhelm, G. S. Mcmaster, Dorothy M. Harrell
Nitrogen And Dry Matter Distribution By Culm And Leaf Position At Two Stages Of Vegetative Growth In Winter Wheat, Wally Wilhelm, G. S. Mcmaster, Dorothy M. Harrell
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Knowledge of N and assimilate partitioning in wheat (Triticum aestivum L.) improves management efficacy and crop model development. Our purpose was to describe N and dry matter distribution during vegetative growth of blades, sheaths, and internodes on four culms. Winter wheat grown at the Colorado State University Horticultural Farm was sampled at Haun Stage 5 and jointing. Samples were dried, weighed, and analyzed for N. As the canopy developed and older tissue contributed more of total tissue, N concentration decreased although N mass and dry weight increased. Dry matter and N mass decreased from MC to T1 and T2 …
Relationship Of Sorghum Kernel Size To Physiochemical, Milling, Pasting, And Cooking Properties, W. J. Lee, Jeffrey F. Pedersen, D. R. Shelton
Relationship Of Sorghum Kernel Size To Physiochemical, Milling, Pasting, And Cooking Properties, W. J. Lee, Jeffrey F. Pedersen, D. R. Shelton
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Effects of kernel size on grain sorghum [Sorghum bicolor (L.) Moench] quality were studied in an experiment designed to separate effects of kernel size from seedlot. The study utilized three sieve fractions of varying kernel diameter (>3.35, >2.80 and >2.36 mm) from six seedlots. Chemical composition, physical characteristics, milling characteristics, pasting properties, and cooking qualities were determined for each kernel size fraction. Large kernels lost less relative mass during 1 min of decortication, were higher in protein concentration, and lower in ash. Milling yields were higher from large kernels, and flour from large kernels had higher water absorbance, …
Swine Response To Misting Synchronized With Meal Events, Roger A. Eigenberg, John A. Nienaber, G. Leroy Hahn, Stephen D. Kachman
Swine Response To Misting Synchronized With Meal Events, Roger A. Eigenberg, John A. Nienaber, G. Leroy Hahn, Stephen D. Kachman
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Prior work has shown that the tympanic temperature of swine increases during an eating bout. An experiment was conducted in a hot environment using timing of misting as a way of reducing the body temperature during meal events. Three treatments were applied to pigs in a constant temperature 30³C environment: no misting, misting just prior to meals, and misting between meals. Two response variables were examined: feed intake and meal duration. Three environmental chambers were used in a Latin–Square layout with each chamber hosting each treatment. Analysis showed feed intake was significantly (P < 0.05) increased by misting just prior to the meal, when compared with no misting or misting between meals. Similarly, meal duration was significantly greater (P < 0.05) for misting just prior to the meal than for the other two treatments. The meal effect appears to result from cooling the pig, thereby reducing the tympanic temperature spike that normally occurs during an activity event such as a meal. The moderation of the body temperature apparently allows the pig to eat for a greater period of time before thermoregulatory controls restrict the meal duration and hence the meal amount. While not conclusive from these short–term observations, increased feed intake should benefit growth performance.
Vaccination Of Pregnant Dams With Intimino157 Protects Suckling Piglets From Escherichia Coli O157:H7 Infection, Evelyn A. Dean-Nystrom, Lisa J. Gansheroff, Melody Mills, Harley W. Moon, Alison D. O’Brien
Vaccination Of Pregnant Dams With Intimino157 Protects Suckling Piglets From Escherichia Coli O157:H7 Infection, Evelyn A. Dean-Nystrom, Lisa J. Gansheroff, Melody Mills, Harley W. Moon, Alison D. O’Brien
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Cattle are important reservoirs of enterohemorrhagic Escherichia coli (EHEC) O157:H7 that cause disease in humans. Both dairy and beef cattle are asymptomatically and sporadically infected with EHEC. Our long-term goal is to develop an effective vaccine to prevent cattle from becoming infected and transmitting EHEC O157:H7 to humans. We used passive immunization of neonatal piglets (as a surrogate model) to determine if antibodies against EHEC O157 adhesin (intiminO157) inhibit EHEC colonization. Pregnant swine (dams) with serum anti-intimin titers of ≤100 were vaccinated twice with purified intiminO157 or shamvaccinated with sterile buffer. IntiminO157-specific antibody titers in …
Pyruvate,Orthophosphate Dikinase In Leaves And Chloroplasts Of C3 Plants Undergoes Light-/Dark- Induced Reversible Phosphorylation, Chris J. Chastain, Jason P. Fries, Julie A. Vogel, Christa L. Randklev, Adam P. Vossen, Sharon K. Dittmer, Erin E. Watkins, Lucas J. Fiedler, Sarah A. Wacker, Katherine Meinhover, Gautam Sarath, Raymond Chollet
Pyruvate,Orthophosphate Dikinase In Leaves And Chloroplasts Of C3 Plants Undergoes Light-/Dark- Induced Reversible Phosphorylation, Chris J. Chastain, Jason P. Fries, Julie A. Vogel, Christa L. Randklev, Adam P. Vossen, Sharon K. Dittmer, Erin E. Watkins, Lucas J. Fiedler, Sarah A. Wacker, Katherine Meinhover, Gautam Sarath, Raymond Chollet
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Pyruvate,orthophosphate (Pi) dikinase (PPDK) is best recognized as a chloroplastic C4 cycle enzyme. As one of the key regulatory foci for controlling flux through this photosynthetic pathway, it is strictly and reversibly regulated by light. This light/dark modulation is mediated by reversible phosphorylation of a conserved threonine residue in the active-site domain by the PPDK regulatory protein (RP), a bifunctional protein kinase/phosphatase. PPDK is also present in C3 plants, although it has no known photosynthetic function. Nevertheless, in this report we show that C3 PPDK in leaves of several angiosperms and in isolated intact spinach (Spinacia …
Repellency Of Ir3535, Kbr3023, Para-Menthane-3,8-Diol, And Deet To Black Salt Marsh Mosquitoes (Diptera: Culicidae) In The Everglades National Park, Donald R. Barnard, Ulrich R. Bernier, Kenneth H. Posey, Rui-De Xue
Repellency Of Ir3535, Kbr3023, Para-Menthane-3,8-Diol, And Deet To Black Salt Marsh Mosquitoes (Diptera: Culicidae) In The Everglades National Park, Donald R. Barnard, Ulrich R. Bernier, Kenneth H. Posey, Rui-De Xue
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
IR3535, KBR3023, para-menthane-3,8-diol (PMD), and deet were evaluated in controlled studies with human subjects (n = 5) for repellency to black salt marsh mosquitoes (Ochlerotatus taeniorhynchus Wiedemann), in the Everglades National Park, FL. In tests of 6-h duration, with an average mosquito biting pressure on exposed forearm skin of 19.5 (±13.7) bites per minute, the mean percent repellencies (SE) for IR3535, KBR3023, PMD, and deet was 88.6 (3.2), 97.5 (1.7), 89.2 (2.9), and 94.8 (2.5), respectively. Mean complete protection times (SE) for IR3535, KBR3023, PMD, and deet were 3.0 (1.0), 5.4 (0.6), 3.8 (1.4), and 5.6 (0.5) h, …
Arsenic(Iii) Oxidation And Arsenic(V) Adsorption Reactions On Synthetic Birnessite, Bruce A. Manning, Scott E. Fendorf, Benjamin Bostick, Donald L. Suarez
Arsenic(Iii) Oxidation And Arsenic(V) Adsorption Reactions On Synthetic Birnessite, Bruce A. Manning, Scott E. Fendorf, Benjamin Bostick, Donald L. Suarez
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The oxidation of arsenite (As(III)) by manganese oxide is an important reaction in both the natural cycling of As and the development of remediation technology for lowering the concentration of dissolved As(III) in drinking water. This study used both a conventional stirred reaction apparatus and extended X-ray absorption fine structure (EXAFS) spectroscopy to investigate the reactions of As(III) and As(V) with synthetic birnessite (MnO2). Stirred reactor experiments indicate that As(III) is oxidized by MnO2 followed by the adsorption of the As(V) reaction product on the MnO2 solid phase. The As(V)-Mn interatomic distance determined by EXAFS analysis …
Growing Rice Grain With Controlled Cadmium Concentrations, Urszula Kukier, Rufus L. Chaney
Growing Rice Grain With Controlled Cadmium Concentrations, Urszula Kukier, Rufus L. Chaney
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Two solution studies were conducted a) to investigate the uptake of zinc (Zn) and cadmium (Cd) by rice plants (Oryza sativa L.) and interaction between these elements, and b) to determine experimental conditions for growing rice grain with desired Cd concentration for an animal feeding study. In both studies, free metal activities of cadmium and cationic microelements were buffered by an excess of chelating agents. The first study was a factorial design with two Zn levels (1.0 and 3.89 μM) and four Cd levels (0.81, 1.44, 2.56 and 4.55 μM) in the solution. In the second study, rice was …
Biomass And Nitrogen Traits Of Summer Pigeon Peas And Winter Wheat Grown For Three Rotations In Containers, Srinivas C. Rao, Charles T. Mackown, James E. Bidlack
Biomass And Nitrogen Traits Of Summer Pigeon Peas And Winter Wheat Grown For Three Rotations In Containers, Srinivas C. Rao, Charles T. Mackown, James E. Bidlack
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Pigeon pea [Cajanus cajan (L.) Millsp.] cultivars, ‘Georgia-1’ and ‘ICPL-87’, were grown without inoculation and with Bradyrhizobium inoculation (multistrain, TAL 1127, or TAL 1132) to evaluate legume dry weight (DW) and nitrogen (N) content, soil mineral N, and subsequent wheat (Triticum aestivum L.) productivity. Pigeon peas were grown during summer and ‘TAM 101’ wheat was grown during winter, along with summer fallow controls fertilized with 0, 45, and 90 kg N ha-1, in 36-cm diam. 20-L pots from 1992 to 1995. Representative pigeon peas were harvested in the fall and remaining plants were incorporated into the …
Quantifying Laboratory And Field Variability To Assess Potential For Carbon Sequestration, R. A. Bowman, J. D. Reeder, B. J. Wienhold
Quantifying Laboratory And Field Variability To Assess Potential For Carbon Sequestration, R. A. Bowman, J. D. Reeder, B. J. Wienhold
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Accurate measurements of soil organic carbon (SOC) levels are essential to assess changes in C sequestration rates. To this end we conducted studies to evaluate laboratory variability in SOC concentration measured at USDA-ARS laboratories in Akron, CO, Cheyenne,WY, and Lincoln, NE. At the Akron laboratory we also evaluated field spatial variability within common cropping treatments in order to assess the potential to quantify significant changes in SOC content associated with rotations of varying cropping intensities. Our data showed very low coefficients of variation for SOC values from each of the three laboratories, and the same average SOC values for soils …
Oviducal Sperm Storage In Turkeys: Spatial Distribution Of Sperm Within The Uterovaginal Junction Sperm-Storage Tubules, M. R. Bakst, Bryan T. Vinyard
Oviducal Sperm Storage In Turkeys: Spatial Distribution Of Sperm Within The Uterovaginal Junction Sperm-Storage Tubules, M. R. Bakst, Bryan T. Vinyard
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The spatial distribution of sperm within the sperm storage tubules (SST) found in
the uterovaginal junction (UVJ) of the turkey is not known. In this study, we inseminated sperm stained with a fluorescent dye (Hoechst 33342) to determine their distribution in SST in the ventral, dorsal, and lateral regions of the proximal, middle, and distal regions of the UVJ. There was no preferential filling in the ventral-dorsal axis of the UVJ. In contrast, preferential filling of the SST was observed in the middle section of the UVJ. Here the individual SST were clearly longer and more pleomorphic than the SST …
Physiology And Reproduction: Embryonic Development From First Cleavage Through Seventy-Two Hours Incubation In Two Strains Of Pekin Duck (Anas Platyrhynchos), V. Dupuy, B. Nersessian, M. R. Bakst
Physiology And Reproduction: Embryonic Development From First Cleavage Through Seventy-Two Hours Incubation In Two Strains Of Pekin Duck (Anas Platyrhynchos), V. Dupuy, B. Nersessian, M. R. Bakst
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Embryonic mortality is a significant problem plaguing the commercial duck industry worldwide. Yet, an objective means to stage development of the duck embryo is lacking. Such a staging procedure, which is described in this study, is essential for the critical and reproducible assessment of embryo development. The morphological features associated with duck embryo development are very similar to those of the chicken, although the duck embryo develops more slowly. The staging scheme presented here provides objective morphological criteria describing the embryonic development of the duck.
Segregation Of Spermatozoa Within Sperm Storage Tubules Of Fowl And Turkey Hens, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue
Segregation Of Spermatozoa Within Sperm Storage Tubules Of Fowl And Turkey Hens, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
In avian species, spermatozoa reside in the oviduct for prolonged periods in specialized structures known as sperm storage tubules, but little is known about the relative distribution of spermatozoa in these tubules after successive inseminations by different males. The staining efficacies of various fluorescent dyes for fowl and turkey spermatozoa were evaluated to investigate one proposed mechanism of sperm competition. Hens were then inseminated at different intervals with stained and unstained spermatozoa to observe the spatial distribution of spermatozoa within the storage tubules. Several novel fluorescent lipophilic tracers that successfully stain mammalian spermatozoa either did not stain fowl or turkey …
Molecular Cloning, Functional Characterization, And Subcellular Localization Of Soybean Nodule Dihydrolipoamide Reductase, Jose F. Moran, Zhaohui Sun, Gautam Sarath, Raul Arredondo-Peter, Euan K. James, Manuel Becana, Robert V. Klucas
Molecular Cloning, Functional Characterization, And Subcellular Localization Of Soybean Nodule Dihydrolipoamide Reductase, Jose F. Moran, Zhaohui Sun, Gautam Sarath, Raul Arredondo-Peter, Euan K. James, Manuel Becana, Robert V. Klucas
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Nodule ferric leghemoglobin reductase (FLbR) and leaf dihydrolipoamide reductase (DLDH) belong to the same family of pyridine nucleotide-disulfide oxidoreductases. We report here the cloning, expression, and characterization of a second protein with FLbR activity, FLbR-2, from soybean (Glycine max) nodules. The cDNA is 1,779 bp in length and codes for a precursor protein comprising a 30-residue mitochondrial transit peptide and a 470-residue mature protein of 50 kD. The derived protein has considerable homology with soybean nodule FLbR-1 (93% identity) and pea (Pisum sativum) leaf mitochondria DLDH (89% identity). The cDNA encoding the mature protein was overexpressed …
Soil Health As An Indicator Of Sustainable Management, John W. Doran, Stamatis Stamatiadis, John Haberern
Soil Health As An Indicator Of Sustainable Management, John W. Doran, Stamatis Stamatiadis, John Haberern
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Population growth, a widening gap between the rich and poor, environmental degradation, and a re-evaluation of energy use and alternatives will shape life in the 21st century. We will be challenged to increase food supplies for a global population one-and-a-half to two times its current size. But as agricultural systems grow to meet the demands of more people, increased pressure will be placed on our natural resources: competition for land, water and energy resources from both urban and industrial sectors becomes more acute and the available land base remains static or shrinks. Under current practices increased food production will greatly …
Electrical Conductivity Monitoring Of Soil Condition And Available N With Animal Manure And A Cover Crop, R. A. Eigenberg, John W. Doran, John A. Nienaber, Richard B. Ferguson, B. L. Woodbury
Electrical Conductivity Monitoring Of Soil Condition And Available N With Animal Manure And A Cover Crop, R. A. Eigenberg, John W. Doran, John A. Nienaber, Richard B. Ferguson, B. L. Woodbury
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Development of sustainable agricultural management systems will depend, in part, on the ability to better use renewable resources, such as animal manure, and to synchronize the levels of soil available N with crop plant needs during the growing season. This study was conducted at the US Meat Animal Research Center in the central USA to determine whether differences in electromagnetic (EM) soil conductivity and available N levels over a growing season can be linked to feedlot manure/compost application and use of a green winter cover crop. A series of soil conductivity maps of a research cornfield were generated using global …
Identification Of Waxy Wheat By Near-Infrared Reflectance Spectroscopy, S. R. Delwiche, Robert A. Graybosch
Identification Of Waxy Wheat By Near-Infrared Reflectance Spectroscopy, S. R. Delwiche, Robert A. Graybosch
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Newly developed low amylose wheats (Triticum aestivum L.) have unique processing characteristics and thus allow millers to blend defined levels of amylose in mixes requiring low-amylose flour. The amount of amylose synthesized during grain fill is dependent on the expression of three structural genes that encode isoforms of granule-bound starch synthase (GBSS). Lines possessing null alleles at the three waxy (wx) loci produce starch that lacks amylose. While such wheats are readily identified by iodine staining, their identification in wheat marketing and production systems would be facilitated by the use of rapid, spectral methods. The present study …
Threat Of Foreign Arthropod-Borne Pathogens To Livestock In The United States, Ralph A. Bram, John E. George, Robert E. Reichard, Walter J. Tabachnick
Threat Of Foreign Arthropod-Borne Pathogens To Livestock In The United States, Ralph A. Bram, John E. George, Robert E. Reichard, Walter J. Tabachnick
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
There are many exotic animal pathogens throughout the world that, if introduced into the United States, could have a significant detrimental impact on the health of livestock, agricultural economy, the environment, and public health. Many of these pathogens are arthropod-borne and potential vectors are readily available in the United States. A number of these arthropod-borne pathogens are discussed here as examples that illustrate the potential risk and the consequences of inadvertent introductions. Several International agencies have a role in global surveillance and in controlling animal diseases should they begin to expand their range. The risk to the United States is …
A Personal Account Of Creating The Sterile Insect Technique To Eradicate The Screwworm From Curacao, Florida And The Southeastern United States, Alfred H. Baumhover
A Personal Account Of Creating The Sterile Insect Technique To Eradicate The Screwworm From Curacao, Florida And The Southeastern United States, Alfred H. Baumhover
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The history is recounted of developing the sterile insect technique to eradicate the screwworm, Cochliomyia hominivorax (Coquerel), from the Caribbean island of Curacao, Florida and the southeastern U.S. Observations of screwworm biology and challenges faced in conducting these eradication projects are described by the author who worked on all aspects of the research and field operations. Eradication was first demonstrated on Curacao, essentially a 170 mi2 outdoor laboratory. The population dynamics of the wild screwworm was determined and overflooding ratios and dispersal patterns essential for population suppression were defined. Eradication was achieved with minimal resources by attacking the pest …
Continuous Production Of Extracellular Antioxidants In Suspension Cells Attenuates The Oxidative Burst Detected In Plant Microbe Interactions, C. Jacyn Baker, Nichole R. O'Neil, Kenneth Deahl, John Lydon
Continuous Production Of Extracellular Antioxidants In Suspension Cells Attenuates The Oxidative Burst Detected In Plant Microbe Interactions, C. Jacyn Baker, Nichole R. O'Neil, Kenneth Deahl, John Lydon
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Suspension cells of Solanacearum tuberosum and Nicotiana tabacum placed in fresh buffer rapidly produce and maintain significant pools of extracellular antioxidants. The extracellular antioxidant was detected by first adding a known amount of exogenous H2O2 to samples and then immediately measuring the remaining H2O2. The difference between the amount added and amount remaining was used to determine the antioxidant capacity of the sample. This extracellular antioxidant pool attenuates levels of hydrogen peroxide produced during plant–bacterial interactions. When tobacco cells were inoculated with an isolate Pseudomonas syringae pv. syringae that causes a hypersensitive response …
Reductions In Grassland Species Evenness Increase Dicot Seedling Invasion And Spittle Bug Infestation, Brian J. Wilsey, H. Wayne Polley
Reductions In Grassland Species Evenness Increase Dicot Seedling Invasion And Spittle Bug Infestation, Brian J. Wilsey, H. Wayne Polley
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Previous experiments that tested whether diverse plant communities have lower invasibility have all varied species richness. We experimentally varied evenness of four grassland species (three grasses and one forb) by planting a field experiment in Texas, and monitored the number of unplanted dicot and monocot species that invaded plots for two growing seasons. By varying evenness, we eliminated any sampling effect in our diversity treatment, because all plots contained the same plant species. Experimentally reducing evenness led to a greater number of dicot invaders, which emerged in plots throughout the growing season, but had less of an effect on monocot …
Review And Interpretation: Nitrogen Management Strategies To Reduce Nitrate Leaching In Tile-Drained Midwestern Soils, Dana L. Dinnes, Douglas L. Karlen, Dan B. Jaynes, Thomas C. Kaspar, Jerry L. Hatfield, Thomas S. Colvin, Cynthia A. Cambardella
Review And Interpretation: Nitrogen Management Strategies To Reduce Nitrate Leaching In Tile-Drained Midwestern Soils, Dana L. Dinnes, Douglas L. Karlen, Dan B. Jaynes, Thomas C. Kaspar, Jerry L. Hatfield, Thomas S. Colvin, Cynthia A. Cambardella
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Balancing the amount of N needed for optimum plant growth while minimizing the NO3 that is transported to ground and surface waters remains a major challenge for everyone attempting to understand and improve agricultural nutrient use efficiency. Our objectives for this review are to examine how changes in agricultural management practices during the past century have affected N in Midwestern soils and to identify the types of research and management practices needed to reduce the potential for nonpoint NO3 leakage into water resources. Inherent soil characteristics and management practices contributing to nonpoint NO3 loss from Midwestern soils, …
Effect Of Habitat Depth On Host Location By Five Species Of Parasitoids (Hymenoptera: Pteromalidae, Chalcididae) Of House Flies (Diptera: Muscidae) In Three Types Of Substrates, Christopher Geden
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Four species of pteromalid parasitoids [Muscidifurax raptor Girault & Sanders, Spalangia cameroni Perkins, Spalangia endius Walker, Spalangia gemina Boucek, and the chalcidid Dirhinus himalayanus (Masi)] were evaluated for their ability to locate house fly pupae at various depths in poultry manure (41% moisture), fly rearing medium (43% moisture), and sandy soil (4% moisture) from a dairy farm. Searching activity in manure was largely confined to the surface (M. raptor, D. himalayanus, and S. gemina) or to depths of up to 2 cm below the surface (S. endius, S. cameroni). S. cameroni was the …
An Innovative Soil Test For Predicting Nitrogen Mineralization, F. M. Hons, R. L. Haney, A J. Franzluebbers
An Innovative Soil Test For Predicting Nitrogen Mineralization, F. M. Hons, R. L. Haney, A J. Franzluebbers
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
A routine soil testing procedure for soil N mineralization is needed that is rapid and precise. Not accounting for N mineralization can result in over application of N, especially in soils with a history of manure application. Our objectives were to compare results from a recently proposed rapid lab procedure with i) long-term N mineralization under standard laboratory conditions, ii) actual forage N uptake from soil receiving dairy cattle (Bas taurus) manure in a two-year field study and iii) yields of various crops throughout Texas and Oklahoma. The rapid procedure is based on the quantity of CO2 …
Soil Carbon, Nitrogen Use, And Water Use Affected By Rotation In The Northern Corn Belt, Joseph L. Pikul Jr., Thomas E. Schumacher, Merle Vigil, Walter E. Riedell
Soil Carbon, Nitrogen Use, And Water Use Affected By Rotation In The Northern Corn Belt, Joseph L. Pikul Jr., Thomas E. Schumacher, Merle Vigil, Walter E. Riedell
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Diversified crop rotation may improve production efficiency, reduce fertilizer nitrogen (N) requirements for com (Zea mays L.) and increase soil carbon (C) storage. Objectives were to determine effect of rotation and fertilizer N on soil C sequestration, water use, and N use. An experiment was started in 1990 on a Barnes clay loam (fine-loamy, mixed, superactive, frigid Calcic Hapludoll) near Brookings, South Dakota. Primary tillage on all rotations was with a chisel plow. Rotations were continuous com (CC), com-soybean [Glycine max (L.) Merr.] (CS) and a 4-year rotation of corn-soybean-wheat (Triticum aestivum L.) companion seeded with alfalfa …
Response Of Irrigated Corn To Nitrogen Fertility Level Within Two Tillage Systems, Ardell D. Halvorson, Walter Bausch, Harold Duke, Curtis Reule
Response Of Irrigated Corn To Nitrogen Fertility Level Within Two Tillage Systems, Ardell D. Halvorson, Walter Bausch, Harold Duke, Curtis Reule
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Irrigated farmers generally utilize intensive tillage to manage crop residues and prepare a seedbed for com. Nitrogen fertilizer management practices have been developed for conventional-till (CT) irrigated com production. Little information is available for no-till (NT) and reduced-till (RT) irrigated com production systems. This paper compares the response of irrigated continuous com to N fertility level under CT and NT or RT production systems on a Fort Collins clay loam soil from 1999 through 2001. Grain yields increased similarly with increasing available N level [soil NO3-N (0-3 ft) plus fertilizer N added] in 1999,2000, and 2001 for both …
Nitrogen Fertilization Of Irrigated Corn In A High Residual Soil N Environment In The Arkansas River V Alley, Ardell D. Halvorson, Frank Schweissing, Curtis Reule
Nitrogen Fertilization Of Irrigated Corn In A High Residual Soil N Environment In The Arkansas River V Alley, Ardell D. Halvorson, Frank Schweissing, Curtis Reule
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
High levels of residual soil NO3-N are present in the soils in the Arkansas River Valley where melons and other vegetable crops are produced. The amount of N fertilizer required to optimize the yield potential of crops, such as corn, following vegetables needs to evaluated to reduce NO3-N leaching potential in the Valley where high NO3-N levels have been reported in the ground water. This study evaluated the effects of N fertilizer rate (0, 50, 100, 150, 200, and 250 lb N/a) and N source (urea and Polyon®3) on corn yields following …
Soil Electrical Conductivity Classification: A Basis For Site-Specific Management In Semiarid Cropping Systems, Cinthia K. Johnson, David A. Mortensen, Brian J. Wienhold, John F. Shanahan, John W. Doran
Soil Electrical Conductivity Classification: A Basis For Site-Specific Management In Semiarid Cropping Systems, Cinthia K. Johnson, David A. Mortensen, Brian J. Wienhold, John F. Shanahan, John W. Doran
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Site specific management (SSM) has the potential to improve both economic and ecological outcomes in agriculture. Effective SSM requires strong and temporally consistent relationships between identified management zones, underlying soil physical, chemical and biological parameters defining yield potential, and crop yield. In a farm-scale (250 ha) experiment in semiarid northeastern Colorado, each of eight 31-ha fields was individually mapped for soil apparent electrical conductivity (ECa) and classified into four management zones (ranges of ECa). Soil analyses revealed a strong negative relationship between ECa zones and soil parameters associated with innate fertility (P ≤ 0.06). …