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- Bemisia tabaci (2)
- Elevated CO2 (2)
- Grassland (2)
- Marker-assisted breeding (2)
- Rhg4 (2)
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- Soybean cyst nematode (2)
- AFLP (1)
- Active oxygen (1)
- Adaptive management (1)
- Albumin; Fasted; Fatty acid oxidation; Fed; Methyl-β-cyclodextrin; Palmitate; Swine; Tracer methodology (1)
- Alien plants (1)
- Alphitobius diaperinus (1)
- Amplified fragment length polymorphism (AFLP) (1)
- Arthropod predators (1)
- B. argentifolii (1)
- Bacteria (1)
- Bacterial respiration (1)
- Bemisia argentifolii (1)
- Biological control (1)
- CO2 effect (1)
- CO2 gradient (1)
- Canopy CO2 flux (1)
- Cattle (1)
- Classification (1)
- Conservation biological control (1)
- Cool-season grasses (1)
- Corn (1)
- DNA Extraction; PCR; Purification; Sediment; Size exclusion chromatography; Soil (1)
- Dermestes maculatus (1)
- Diapriidae spp. (1)
Articles 1 - 30 of 57
Full-Text Articles in Life Sciences
Oestrus Ovis In Sheep: Relative Third-Instar Populations, Risks Of Infection And Parasitic Control, Guillaume Tabouret, Philippe Jacquiet, Philip Scholl, Philippe Dorchies
Oestrus Ovis In Sheep: Relative Third-Instar Populations, Risks Of Infection And Parasitic Control, Guillaume Tabouret, Philippe Jacquiet, Philip Scholl, Philippe Dorchies
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Oestrus ovis (L.) (Diptera: Oestridae), the nasal bot fly, has a relatively short free-living life cycle outside of the host, and therefore it is necessary to know when the parasitic period occurs in order to prevent the clinical signs and economic losses caused by this parasite. The length of this parasitic portion of the life cycle is quite variable: a few weeks to several months depending on the season and climatic conditions. Surveys of Oestrus ovis larval populations in sheep show different results on the number of generations according to the local climate. Mean monthly larval profiles of L1 and …
Structure And Temporal Dynamics Of Populations Within Wheat Streak Mosaic Virus Isolates, Jeffrey S. Hall, Roy C. French, Thomas Jack Morris, Drake C. Stenger
Structure And Temporal Dynamics Of Populations Within Wheat Streak Mosaic Virus Isolates, Jeffrey S. Hall, Roy C. French, Thomas Jack Morris, Drake C. Stenger
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Variation within the Type and Sidney 81 strains of wheat streak mosaic virus was assessed by single-strand conformation polymorphism (SSCP) analysis and confirmed by nucleotide sequencing. Limiting-dilution subisolates (LDSIs) of each strain were evaluated for polymorphism in the P1, P3, NIa, and CP cistrons. Different SSCP patterns among LDSIs of a strain were associated with single-nucleotide substitutions. Sidney 81 LDSI-S10 was used as founding inoculum to establish three lineages each in wheat, corn, and barley. The P1, HC-Pro, P3, CI, NIa, NIb, and CP cistrons of LDSI-S10 and each lineage at passages 1, 3, 6, and 9 were evaluated for …
Frequency Grid-A Simple Tool For Measuring Grassland Establishment, Kenneth P. Vogel, Robert A. Masters
Frequency Grid-A Simple Tool For Measuring Grassland Establishment, Kenneth P. Vogel, Robert A. Masters
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Simple, reliable tools are needed by land managers to quantify establishment success when seeding or re-seeding pastures or rangeland. A frequency grid was designed to measure seedling or plant establishment success for a single species, mixtures of species, or single species of a mixture. The frequency grid is a metal frame containing 25 squares (5 x 5) or cells and can be made from concrete reinforcing sheets that have 15 x 15 cm squares. When used, the frequency grid is either randomly or systematically placed within a seeded area. The number of cells containing 1 or more seeded plants is …
Accumulation And Consumption Of Odorous Compounds In Feedlot Soils Under Aerobic, Fermentative, And Anaerobic Respiratory Conditions, D. N. Miller
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Agricultural odors present an increasingly difficult challenge to livestock producers, yet very little information is available on the microbiology of odor production or microbial factors that regulate the emission of odors. This study examined the microbial potential for odor production and odor consumption in two soils from a cattle production facility in central Nebraska. The two soils tested were collected from a feedlot pen and a runoff ditch below the pen and contained high- and low-fecal matter content, respectively. These soils were tested for their ability to produce and consume a mixture of VFA and aromatic compounds (phenols and indoles) …
Corn Stalk Nitrate Concentration Profile: Implications For The End-Of-Season Stalk Nitrate Test, Wally Wilhelm, Gary E. Varvel, James S. Schepers
Corn Stalk Nitrate Concentration Profile: Implications For The End-Of-Season Stalk Nitrate Test, Wally Wilhelm, Gary E. Varvel, James S. Schepers
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The end-of-season corn (Zea maysL.) stalk nitrate-N test was developed as a post-mortem to determine if excessive or insufficient N was available to the corn crop during the latter part of the season. The stalk section specified for the test was very specific, the 20 cm-long section between 15 and 35 cm above the soil. Under production conditions, it may not always be possible to collect this precise stalk section. The objective of this study was to determine how nitrate concentration varied within the stalk from the soil level to the ear node, and how this variation could …
‘Forrest’ Resistance To The Soybean Cyst Nematode Is Bigenic: Saturation Mapping Of The Rhg1 And Rhg4 Loci, K. Meksem, P. Pantazopoulos, V. N. Njiti, D. L. Hyten, P. R. Arelli, D. A. Lightfoot
‘Forrest’ Resistance To The Soybean Cyst Nematode Is Bigenic: Saturation Mapping Of The Rhg1 And Rhg4 Loci, K. Meksem, P. Pantazopoulos, V. N. Njiti, D. L. Hyten, P. R. Arelli, D. A. Lightfoot
Department of Agronomy and Horticulture: Faculty Publications
Field resistance to cyst nematode (SCN) race 3 (Heterodera glycines I.) in soybean [Glycine max (L.) Merr.] cv ‘Forrest’ is conditioned by two QTLs: the underlying genes are presumed to include Rhg1 on linkage group G and Rhg4 on linkage group A2. A population of recombinant inbred lines (RILs) and two populations of near-isogenic lines (NILs) derived from a cross of Forrest × Essex were used to map the loci affecting resistance to SCN. Bulked segregant analysis, with 512 AFLP primer combinations and microsatellite markers, produced a high-density genetic map for the intervals carrying Rhg …
Thermoregulatory Profile Of A Newer Genetic Line Of Pigs, T. M. Brown-Brandl, R. A. Eigenberg, John A. Nienaber, Stephen D. Kachman
Thermoregulatory Profile Of A Newer Genetic Line Of Pigs, T. M. Brown-Brandl, R. A. Eigenberg, John A. Nienaber, Stephen D. Kachman
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Researchers and producers alike have noted the increased susceptibility to heat stress exhibited by the newer genetic lines of pigs. A study was conducted to gather baseline information on the effects of acute heat stress on total heat production (THP), respiratory quotient (RQ), respiration rate (RR), and rectal temperature (Trectal ) and to investigate the dynamic interaction of these parameters in growing–finishing barrows. Sixteen moderate–lean growth barrows were randomly assigned to a set of treatments as dictated by a repeated 4x4 Latin square crossover design. Pigs were moved from an individual pen to an indirect calorimeter where one …
Invited Synthesis Paper: Principles And Practices For Managing Rangeland Invasive Plants, Robert A. Masters, Roger Sheley
Invited Synthesis Paper: Principles And Practices For Managing Rangeland Invasive Plants, Robert A. Masters, Roger Sheley
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Invasive plants reduce the capacity of ecosystems to provide goods and services required by society, alter ecological processes, and can displace desirable species. They can reduce wildlife habitat quality, riparian area integrity, rangeland economic value, and enterprise net returns. The invasion process is regulated by characteristics of the invading plant and the community being invaded. The presence and spread of invasive plants is often symptomatic of underlying management problems that must be corrected before acceptable, long-term rangeland improvement can be achieved. Disturbance appears to be important early in the invasion process because it creates vacant niches that alien plants can …
Murine Monoclonal Antibodies Against Escherichia Coli O4 Lipopolysaccharide And H5 Flagellin, Mildred Rivera-Betancourt, James E. Keen
Murine Monoclonal Antibodies Against Escherichia Coli O4 Lipopolysaccharide And H5 Flagellin, Mildred Rivera-Betancourt, James E. Keen
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Two murine monoclonal antibodies (MAb), 2C5-F10 and 8D1-H10, reactive with Escherichia coli O4 and H5 antigens, respectively, were generated and characterized. Enzyme immunoassays and immunoblots demonstrated that MAb 2C5-F10 reacted specifically with lipopolysaccharide O antigen of E. coli O4 isolates, while MAb 8D1-H10 reacted with E. coli strains expressing H5 flagella.
Genotypic Analyses Of Escherichia Coli O157:H7 And O157 Nonmotile Isolates Recovered From Beef Cattle And Carcasses At Processing Plants In The Midwestern States Of The United States, Genevieve A. Barkocy-Gallagher, Terrance M. Arthur, Gregory R. Siragusa, James E. Keen, Robert O. Elder, William Laegreid, Mohammad Koohmaraie
Genotypic Analyses Of Escherichia Coli O157:H7 And O157 Nonmotile Isolates Recovered From Beef Cattle And Carcasses At Processing Plants In The Midwestern States Of The United States, Genevieve A. Barkocy-Gallagher, Terrance M. Arthur, Gregory R. Siragusa, James E. Keen, Robert O. Elder, William Laegreid, Mohammad Koohmaraie
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Escherichia coli O157:H7 and O157 nonmotile isolates (E. coli O157) previously were recovered from feces, hides, and carcasses at four large Midwestern beef processing plants (R. O. Elder, J. E. Keen, G. R. Siragusa, G. A. Barkocy-Gallagher, M. Koohmaraie, and W. W. Laegreid, Proc. Natl. Acad. Sci. USA 97:2999–3003, 2000). The study implied relationships between cattle infection and carcass contamination within single-source lots as well as between preevisceration and postprocessing carcass contamination, based on prevalence. These relationships now have been verified based on identification of isolates by genomic fingerprinting. E. coli O157 isolates from all positive samples were analyzed …
Chemical Compounds That Attract Arthropods- Patent 2001, Ulrich R. Bernier, Daniel L. Kline, Donald Barnard, Kenneth Posey, Matthew Booth, Richard A. Yost
Chemical Compounds That Attract Arthropods- Patent 2001, Ulrich R. Bernier, Daniel L. Kline, Donald Barnard, Kenneth Posey, Matthew Booth, Richard A. Yost
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Compositions and methods employing the compositions for attracting arthropods. The compositions comprise at least one compound of formula I and at least one compound from group II.
Performance Of A Grid-Connected Photovoltaic System Using Actual And Kriged Hourly Solar Radiation, G. G. Merino, David Jones, Laverne E. Stetson
Performance Of A Grid-Connected Photovoltaic System Using Actual And Kriged Hourly Solar Radiation, G. G. Merino, David Jones, Laverne E. Stetson
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
In this article the performance of a grid-connected PV system supplying a farmstead was evaluated using a commercially available energy balance simulation model, Hybrid2. By performing annual hourly simulations, the influence of system size, actual radiation data, and estimated radiation data on economic and energy production were assessed. The estimated radiation data were developed from kriging actual radiation data from 16 weather stations in western Nebraska. The results indicated that the capital costs associated with a PV system dictate the economic performance of the overall system. The energy costs associated with the grid-connected PV system were six times the retail …
Restoring Tallgrass Prairie Species Mixtures On Leafy Spurge-Infested Rangeland, Robert A. Masters, Daniel Beran, Roch E. Gaussoin
Restoring Tallgrass Prairie Species Mixtures On Leafy Spurge-Infested Rangeland, Robert A. Masters, Daniel Beran, Roch E. Gaussoin
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Leafy spurge (Euphorbia esula L.) reduces northern Great Plains rangeland carrying capacity. Treatment strategies were evaluated that suppressed leafy spurge and facilitated establishment of mixtures of native grasses and legumes on range sites near Mason City and Tilden, Nebr. Glyphosate at 1,600 g a.i. (active ingredient) ha-1 was applied with or without imazapic at 140 or 210 g a.i. ha-1 in October 1995. In April 1996, standing crop was burned or mowed. Mixtures of native grasses [big bluestem (Andropogon gerardii Vitman), indiangrass (Sorghastrum nutans (L.) Nash), switchgrass (Panicum virgatum L.), little bluestem (Schizachyrium …
Modeling Vegetative Buffer Performance Considering Topographic Data Accuracy, Jason M. Brothers, Dean E. Eisenhauer, Matthew J. Helmers, Michael G. Dosskey, Thomas G. Franti
Modeling Vegetative Buffer Performance Considering Topographic Data Accuracy, Jason M. Brothers, Dean E. Eisenhauer, Matthew J. Helmers, Michael G. Dosskey, Thomas G. Franti
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Riparian buffers are a promising tool in efforts to reduce sediment contribution to streams. Models that predict the capacity of buffers to trap sediment have recently been developed. A number of parameters that are required to conduct such modeling efforts are derived from the topography of the site. In this study, three topographic data sources were used to generate the model input for an agricultural field with a riparian buffer. The runoff and sediment transport in the system was then simulated for three years. As a result, the area that contributed runoff and sediment to the buffer was substantially different …
Mutations In The Csgd Promoter Associated With Variations In Curli Expression In Certain Strains Of Escherichia Coli O157:H7, Gaylen A. Uhlich, James E. Keen, Robert O. Elder
Mutations In The Csgd Promoter Associated With Variations In Curli Expression In Certain Strains Of Escherichia Coli O157:H7, Gaylen A. Uhlich, James E. Keen, Robert O. Elder
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Single-base-pair csgD promoter mutations in human outbreak Escherichia coli O157:H7 strains ATCC 43894 and ATCC 43895 coincided with differential Congo red dye binding from curli fiber expression. Red phenotype csgD::lacZ promoter fusions had fourfold-greater expression than white promoter fusions. Cloning the red variant csgDEFG operon into white variants induced the red phenotype. Substrate utilization differed between red and white variants.
Erythropoietin Mrna Expression In Pig Embryos, H. G. Klemcke, J. L. Vallet, R. K. Christenson, P. L. Pearson
Erythropoietin Mrna Expression In Pig Embryos, H. G. Klemcke, J. L. Vallet, R. K. Christenson, P. L. Pearson
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
To address whether altered erythropoietin (EPO) synthesis might be involved in prenatal pig mortality, studies were conducted to measure porcine embryonic EPO mRNA expression during early gestation (days 24–40). Three pig models differing in embryonic survival from days 24–40 were investigated: intact white crossbred gilts (INT), white crossbred gilts that were unilaterally hysterectomized-ovariectomized before puberty and whose pregnant uterus constituted a crowded environment (UHO), and prolific, intact Meishan gilts (ME). A partial cDNA for porcine EPO, developed via reverse transcription and polymerase chain reaction procedures was used to generate a 32P-labeled probe for use in Northern analyses. In an initial …
Modeling A Spring Wheat Crop Under Elevated Co2 And Drought, S. Grossman-Clarke, P. J. Pinter Jr., T. Kartschall, B. A. Kimball, D. J. Hunsaker, G. W. Wall, R. L. Garcia, R. L. Lamorte
Modeling A Spring Wheat Crop Under Elevated Co2 And Drought, S. Grossman-Clarke, P. J. Pinter Jr., T. Kartschall, B. A. Kimball, D. J. Hunsaker, G. W. Wall, R. L. Garcia, R. L. Lamorte
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
• The simulation model DEMETER was used here to investigate which mechanisms led to a larger CO2 effect on biomass production and yield of a spring wheat crop under drought compared with unlimited water supply.
• Field data of the free-air CO2enrichment (FACE) wheat experiments in Arizona (1993–94) were used to test the model. The influence of a particular mechanism leading to a higher CO2effect under drought was investigated by eliminating the influence of the other causes on the simulation results on selected days during the growing seasons.
• A larger CO2effect under …
Plant-Derived Oils Reduce Pathogens And Gaseous Emissions From Stored Cattle Waste, Vincent H. Varel, Daniel N. Miller
Plant-Derived Oils Reduce Pathogens And Gaseous Emissions From Stored Cattle Waste, Vincent H. Varel, Daniel N. Miller
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Carvacrol and thymol in combination at 6.7 mM each completely inhibited the production of short-chain volatile fatty acids and lactate from cattle waste in anoxic flasks over 23 days. Fecal coliforms were reduced from 4.6 x 106 to 2.0 x 103 cells per ml 2 days after treatment and were nondetectable within 4 days. Total anaerobic bacteria were reduced from 8.4 x 1010 to 1.5 x 107 cells per ml after 2 days and continued to be suppressed to that level after 14 days. If the concentration of carvacrol or thymol were doubled (13.3 mM), either …
Evaluation Of Gel Filtration Resins For The Removal Of Pcr-Inhibitory Substances From Soils And Sediments, Daniel N. Miller
Evaluation Of Gel Filtration Resins For The Removal Of Pcr-Inhibitory Substances From Soils And Sediments, Daniel N. Miller
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
A variety of gel filtration resins (Sephadex G200 and G150; Sepharose 6B, 4B and 2B; Bio-Gel P100, P200; and Toyopearl HW 55, HW 65, and HW 75) were evaluated for their efficacy in removing PCR-inhibitory substances from feedlot soil DNA crude extracts using gravity-flow disposable columns. Sepharose resins demonstrated the best properties for DNA purification when compared to other gel filtration resins, and Sepharose 2B was the most efficient purification resin based upon flow rate and the elution of DNA and humic acids from the columns. A method for purifying large solution volumes of DNA extract economically was also developed …
Intsormil 2001 Annual Report, John M. Yohe, Thomas Crawford Jr., Joan Frederick, Dorothy Stoner
Intsormil 2001 Annual Report, John M. Yohe, Thomas Crawford Jr., Joan Frederick, Dorothy Stoner
INTSORMIL Impacts and Bulletins
Presently, worldwide, more than 800 million people are hungry and over one billion are desperately poor, and food demand is increasing rapidly. The majority of poor live in rural areas in developing countries and agricultural and food systems development is vital to economic growth; improving environmental quality; strengthening nutrition, health and child survival; improving the status of women; and promoting democratization. It is estimated that, between 1980 and 2030, the population ofow- and middle-income countries will more than double-to seven billion, compared with one billion for high-income countries. In the next 35 years, 2.5 billion people will be added to …
Clear-Sky Albedo Measured At Seven Rangland Sites In Southwest Idaho, Clayton L. Hanson
Clear-Sky Albedo Measured At Seven Rangland Sites In Southwest Idaho, Clayton L. Hanson
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
As a component of the energy budget, albedo is used in the calculation of evapotranspiration in many natural resource and hydrologic models. There are few measurements of albedo over sagebrush-dominated rangelands, so albedo was measured at seven sites on the Reynolds Creek Experimental Watershed in southwest Idaho during 1989–1993. For all sites, the average albedo measured during midday under clear skies was 0.14 during the growing season. Albedo varied from a low of 0.11 during June at the Mountain big sagebrush site to a high of 0.17 at the low-elevation Wyoming big sagebrush site. Albedo varied little between about 2 …
Dis And Distributed Watershed Models I, Jurgen Garbrecht, Fred L. Ogden, Paul A. Debarry, David R. Maidment
Dis And Distributed Watershed Models I, Jurgen Garbrecht, Fred L. Ogden, Paul A. Debarry, David R. Maidment
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The increasing proliferation of spatial data, geographic information systems (GIS), and models for hydrologic applications provide many new investigation opportunities but also present a number of challenges for the uninitiated water resources practitioner. This two-part paper is intended for the practicing engineer who wants to expand into the arena of spatial data and distributed watershed modeling. It provides an integrated overview of the multiple facets of data-GIS-modeling issues and a source of background information for selection and application of GIS in watershed modeling. This first paper addresses selected spatial data issues, data structures and projections, data sources, and information on …
Automated Gas Sampling System For Laboratory Analysis Of Ch4 And N2O, Spencer L. Arnold, Timothy B. Parkin, John W. Doran, Bahman Eghball, Arvin R. Mosier
Automated Gas Sampling System For Laboratory Analysis Of Ch4 And N2O, Spencer L. Arnold, Timothy B. Parkin, John W. Doran, Bahman Eghball, Arvin R. Mosier
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Analyzing the flux of CH4 and N2O from soil is labor intensive when conventional hand injection techniques are utilized in gas chromatography. An automated gas sampling system was designed and assembled from a prototype developed at the National Soil Tilth Laboratory in Ames, IA. The sampler was evaluated for accuracy and precision when attached to a Varian 3700 gas chromatograph configured with flame ionization and electron capture detectors. The automated gas sampling system is easy to operate and provides acceptable results (standards ranging from 1.0–5.0 ppmv CH4 and 0.342–2.0 ppmv N2O had coefficients of …
Innovative Remote Sensing Techniques To Increase Nitrogen Use Efficiency Of Corn, Walter C. Bausch, Kenan Diker
Innovative Remote Sensing Techniques To Increase Nitrogen Use Efficiency Of Corn, Walter C. Bausch, Kenan Diker
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Nitrogen (N) fertilizer recommendations made without adequate knowledge of the N supply capability of a soil can lead to inefficient use of N. Proper crediting of N from manure and legumes as well as mineralization of N from organic matter is difficult. Remote sensing techniques that use the crop to indicate its N status show considerable promise for improving N management. Objectives of this paper were twofold: 1) to compare the N Reflectance Index (NRI) calculated from ground-based radiometer measurements acquired over irrigated corn (Zea mays L.) at a nadir view (0 °) and an oblique view (75 °) …
Interlaboratory Comparison Of Soil Phosphorus Extracted By Various Soil Test Methods, Peter J.A. Kleinman, A. N. Sharpley, K. Gartley, W. M. Jarrell, S. Kuo, R. G. Menon, R. Myers, K. R. Reddy, E. O. Skogley
Interlaboratory Comparison Of Soil Phosphorus Extracted By Various Soil Test Methods, Peter J.A. Kleinman, A. N. Sharpley, K. Gartley, W. M. Jarrell, S. Kuo, R. G. Menon, R. Myers, K. R. Reddy, E. O. Skogley
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The widespread use of soil phosphorus (P) data, either in the context of agronomic or environmental management, requires an explicit understanding of potential errors related to soil P testing. This study compares a variety of soil P extraction methods, each performed by 9 separate laboratories on 24 soils from across the United States. Soil clay content ranged from 0 to 47%, pH from 4.2 to 8.6, and Mehlich-3 P concentration from 2 to 205 mg kg-1. Average interlaboratory coefficients of variation (CVs) ranged from 0.11 to 0.22 for solution extracts (Bray-1 P, Fe-strip P, Mehlich-3 P, and Olsen …
Evidence For The Innervation Of Sperm Storage Tubules In The Oviduct Of The Turkey (Meleagris Gallopavo), S. L. Freedman, V. G. Akuffo, M. R. Bakst
Evidence For The Innervation Of Sperm Storage Tubules In The Oviduct Of The Turkey (Meleagris Gallopavo), S. L. Freedman, V. G. Akuffo, M. R. Bakst
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
The presence of neural tissue and smooth muscle elements in the vicinity of the oviductal sperm storage tubules at the uterovaginal junction was assessed by several modes of light microscopy. Isolated neurones and small ganglia were identified in the uterovaginal junction of the turkey oviduct. The nerve cell bodies were observed in the tunica mucosa by bright field microscopy. Immunoreactivity against neurofilament antibody and recombinant fragment C of the tetanus toxin reacted with nerve fibres and the nuclei of neurones. Fluorescence microscopy and confocal laser scanning microscopy revealed that nerve fibres continued from the base of the tunica mucosa into …
Managing Crop Residue With Green Manure, Urea, And Tillage In A Rice–Wheat Rotation, Milkha S. Aulakh, T. S. Khera, John W. Doran, Kevin F. Bronson
Managing Crop Residue With Green Manure, Urea, And Tillage In A Rice–Wheat Rotation, Milkha S. Aulakh, T. S. Khera, John W. Doran, Kevin F. Bronson
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Most double-crop grain farmers in South Asia remove or burn cropresidue to facilitate seedbed preparation and to avoid possible yield reductions. This results in loss of soil organic matter (SOM) and nutrients. In this study, we determined whether incorporating wheat (Triticum aestivum L.) residue, rice (Oryza sativa L.) residue, and sesbania (Sesbania aculeta L.) green manure with urea fertilizer N in a rice–wheat cropping system can improve grain yields, N use efficiency, and SOM. We incorporated wheat residue (6 Mg ha-1, C/N = 94), rice residue (6 Mg ha-1, C/N = 63), or …
Simplified Method For Soil Particle-Size Determination To Accompany Soil-Quality Analyses, T. A. Kettler, John W. Doran, T. L.. Gilbert
Simplified Method For Soil Particle-Size Determination To Accompany Soil-Quality Analyses, T. A. Kettler, John W. Doran, T. L.. Gilbert
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Soil textural analysis is a key component of any minimum data set used for assessing soil quality and sustainability of agricultural-management practices. However, conventional methods of soil textural analysis can be costly and time-consuming. The objective of this study was to develop a rapid and simple method for evaluating soil particle-size distribution, which could be employed as a tool for initial soil-quality assessment. The method uses a combination of sieving and sedimentation steps and is designed to be used in conjunction with analysis of particulate organic matter (POM), or as a stand-alone textural analysis. Soils of varied texture and organic-matter …
Oxidative Metabolism In Plant/Bacteria Interactions: Characterization Of The Oxygen Uptake Response Of Bacteria, C. Jacyn Baker, Norton Mock, Kenneth L. Deahl, Bryan Bailey, Daniel P. Roberts
Oxidative Metabolism In Plant/Bacteria Interactions: Characterization Of The Oxygen Uptake Response Of Bacteria, C. Jacyn Baker, Norton Mock, Kenneth L. Deahl, Bryan Bailey, Daniel P. Roberts
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
An increase in oxygen uptake has been previously described in plant cell suspensions treated with bacteria or bacterial elicitors. These studies, regarding oxygen uptake, have all been undertaken from the perspective of the host plant cell reacting to the invading pathogen. In contrast, here we describe and characterize an increase in oxygen uptake by bacterial cells in response to plant suspensions or autoclaved plant cell filtrates. Autoclaved plant cell filtrates stimulated bacterial oxygen uptake by as much as sevenfold within a few minutes after addition. This oxygen uptake response was proportional to both the concentration of the plant cell filtrate …
Oxidative Metabolism In Plant/Bacteria Interactions: Characterization Of A Unique Oxygen Uptake Response Of Potato Suspension Cells, C. Jacyn Baker, E. W. Orlandi, Kenneth L. Deahl
Oxidative Metabolism In Plant/Bacteria Interactions: Characterization Of A Unique Oxygen Uptake Response Of Potato Suspension Cells, C. Jacyn Baker, E. W. Orlandi, Kenneth L. Deahl
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
Plant suspension cells have been shown to respond to bacteria or microbial elicitors by producing active oxygen as well as increasing oxygen uptake. Here we characterize a unique two stage oxygen uptake response of potato suspension cells to heat-killed bacteria. Stage 1 occurred within minutes after the addition of heat-killed bacteria; the potato suspension cells responded with a rapid increase in oxygen uptake and reached a steady state approximately 50 % greater than the initial basal rate. Stage 2 began 20-30 min after this new steady state was achieved and was characterized by a slow increase in the oxygen uptake …