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Switchgrass For Biomass Feedstock In The Usa, Matt Sanderson, Paul Adler, Akwasi Boateng, Michael Casler, Gautam Sarath Dec 2006

Switchgrass For Biomass Feedstock In The Usa, Matt Sanderson, Paul Adler, Akwasi Boateng, Michael Casler, Gautam Sarath

Publications from USDA-ARS / UNL Faculty

Switchgrass has received much study for biomass feedstock production and conversion through research funded by the US-DOE and USDA during the past two decades. We have an improved understanding of the adaptation of existing cultivars and new cultivars with yield and adaptation improvements are now appearing. We also have a good understanding of the agronomics of switchgrass production, mainly from its use as a forage crop. There remain several constraints to switchgrass use in bioenergy cropping systems, including reliable establishment methods to obtain productive stands in the first year, targeted fertilization and nutrient management techniques to efficiently use nitrogen fertilizer ...


Bovine Immune Response To Shiga-Toxigenic Escherichia Coli O157:H7, Mark A. Hoffman, Christian Menge, Thomas A. Casey, William Laegreid, Brad T. Bosworth, Evelyn A. Dean-Nystrom Dec 2006

Bovine Immune Response To Shiga-Toxigenic Escherichia Coli O157:H7, Mark A. Hoffman, Christian Menge, Thomas A. Casey, William Laegreid, Brad T. Bosworth, Evelyn A. Dean-Nystrom

Publications from USDA-ARS / UNL Faculty

Although cattle develop humoral immune responses to Shiga-toxigenic (Stx+) Escherichia coli O157:H7, infections often result in long-term shedding of these human pathogenic bacteria. The objective of this study was to compare humoral and cellular immune responses to Stx+ and Stx- E. coli O157:H7. Three groups of calves were inoculated intrarumenally, twice in a 3-week interval, with different strains of E. coli: a Stx2- producing E. coli O157:H7 strain (Stx2+O157), a Shiga toxin-negative E. coli O157:H7 strain (Stx-O157), or a nonpathogenic E. coli strain (control). Fecal shedding of Stx2+O157 was significantly higher than that ...


Agronomic And Quality Effects In Winter Wheat Of A Gene Conditioning Resistance To Wheat Streak Mosaic Virus, L. A. Divis, R. A. Graybosch, C. J. Peterson, P. Stephen Baenziger, G. L. Hein, B. B. Beecher, T. J. Martin Nov 2006

Agronomic And Quality Effects In Winter Wheat Of A Gene Conditioning Resistance To Wheat Streak Mosaic Virus, L. A. Divis, R. A. Graybosch, C. J. Peterson, P. Stephen Baenziger, G. L. Hein, B. B. Beecher, T. J. Martin

Publications from USDA-ARS / UNL Faculty

Wheat streak mosaic virus (WSMV) is one of the most important diseases limiting winter wheat (Triticum aestivum L.) production in the western Great Plains of North America. There is no known effective WSMV resistance within the primary gene pool of wheat. However, a resistance gene (Wsm1) has been transferred to wheat from a perennial relative, intermediate wheat-grass [Thinopyrum intermedium (Host) Barkworth & DR Dewey]. Nebraska-adapted winter wheat lines carrying Wsm1 were used to characterize the effects of this alien introgression on agronomic and quality traits. Sister-lines from six breeding populations were evaluated under virus-free conditions, and under a naturally ...


The Circuitous Path To The Comparison Of Simulated Values From Crop Models With Field Observations, Albert Weiss, Wally Wilhelm Nov 2006

The Circuitous Path To The Comparison Of Simulated Values From Crop Models With Field Observations, Albert Weiss, Wally Wilhelm

Publications from USDA-ARS / UNL Faculty

The Journal of Agricultural Science, Cambridge has been a fixture in dissemination of crop simulation models and the concepts and data upon which they are built since the inception of computers and computer modeling in the mid-20th century. To quantify the performance of a crop simulation model, model outputs are compared with observed values using statistical measures of bias, i.e. the difference between simulated and observed values. While applying these statistical measures is unambiguous for the experienced user, the same cannot always be said of determining the observed or simulated values. For example, differences in accessing crop development can ...


Convergence Of Agriculture And Energy: Implications For Research And Policy, Kenneth Cassman, Vernon Eidman, Eugene Simpson, Larry Berger, Robert Loomis, Marie Walsh, Todd A. Peterson, Edward Runge Nov 2006

Convergence Of Agriculture And Energy: Implications For Research And Policy, Kenneth Cassman, Vernon Eidman, Eugene Simpson, Larry Berger, Robert Loomis, Marie Walsh, Todd A. Peterson, Edward Runge

Publications from USDA-ARS / UNL Faculty

Access to an adequate energy supply at reasonable cost is crucial for sustained economic growth. Unfortunately, oil prices and the need to import from politically unstable countries lowers the reliability of the U.S. energy supply and hinders economic development. Although biofuels have been identified as an important component of the national strategy to decrease U.S. dependence on imported oil, the ability to sustain a rapid expansion of biofuel production capacity raises new research and policy issues. This document seeks to identify the most critical of these issues to help inform the policy development process. The goal is to ...


Grazing Management Effects On Sediment And Phosphorus In Surface Runoff, Matthew M. Haan, James R. Russell, Wendy J. Powers, John L. Kovar, Jamie L. Benning Nov 2006

Grazing Management Effects On Sediment And Phosphorus In Surface Runoff, Matthew M. Haan, James R. Russell, Wendy J. Powers, John L. Kovar, Jamie L. Benning

Publications from USDA-ARS / UNL Faculty

Sediment and phosphorus (P) in runoff from pastures are potential non–point-source pollutants in surface waters that may be influenced by surface cover, sward height, treading damage, surface slope, soil moisture, and soil P. The objectives of the current study were to quantify sediment and total P loads in runoff produced during simulated rainfall from pastures and to evaluate their relationships with the physical and chemical characteristics of the soil and sward. Five forage management treatments— ungrazed (U), hay harvest/fall stockpile grazing (HS), continuous stocking to a sward height of 5 cm (5C), and rotational stocking to sward heights ...


Comparison Of Heat Tolerance Of Feedlot Heifers Of Different Breeds, T. M. Brown-Brandl, J. A. Nienaber, Roger A. Eigenberg, Terry L. Mader, J. L. Morrow, J. W. Dailey Oct 2006

Comparison Of Heat Tolerance Of Feedlot Heifers Of Different Breeds, T. M. Brown-Brandl, J. A. Nienaber, Roger A. Eigenberg, Terry L. Mader, J. L. Morrow, J. W. Dailey

Publications from USDA-ARS / UNL Faculty

Heat stress in cattle causes decreases in feed intake and feed efficiency; in extreme cases, it can cause death. These losses amount to millions of dollars each year. A study was designed to determine severity of heat stress among four breeds of cattle. Throughout two summers, 256 feedlot heifers of four different breeds were observed. Respiration rates, panting scores, and surface temperatures were taken twice each day on 10 animals/breed for several weeks during the summers of 2002 and 2003. Twenty-four-hour behavior measurements were recorded for four heat-stress and four thermoneutral days. Results showed during the afternoon, Angus cattle ...


Heat Stress Risk Factors Of Feedlot Heifers, T. M. Brown-Brandl, Roger A. Eigenberg, J. A. Nienaber Oct 2006

Heat Stress Risk Factors Of Feedlot Heifers, T. M. Brown-Brandl, Roger A. Eigenberg, J. A. Nienaber

Publications from USDA-ARS / UNL Faculty

Heat stress in cattle results in millions of dollars in lost revenue each year due to production losses, and in extreme cases, death. Death losses are more likely to result from animals vulnerable to heat stress. A study was conducted to determine risk factors for heat stress in feedlot heifers. Over two consecutive summers, a total of 256 feedlot heifers (32/ breed/ year) of four breeds were observed. As a measure of stress, respiration rates and panting scores were taken twice daily (morning and afternoon) on a random sample of 10 heifers/ breed. Weights, condition scores, and temperament scores were ...


Heat Stress Risk Factors Of Feedlot Heifers, Tami M. Brown-Brandl, Roger A. Eigenberg, John A. Nienaber Oct 2006

Heat Stress Risk Factors Of Feedlot Heifers, Tami M. Brown-Brandl, Roger A. Eigenberg, John A. Nienaber

Publications from USDA-ARS / UNL Faculty

Heat stress in cattle results in millions of dollars in lost revenue each year due to production losses, and in extreme cases, death. Death losses are more likely to result from animals vulnerable to heat stress. A study was conducted to determine risk factors for heat stress in feedlot heifers. Over two consecutive summers, a total of 256 feedlot heifers (32/ breed/ year) of four breeds were observed. As a measure of stress, respiration rates and panting scores were taken twice daily (morning and afternoon) on a random sample of 10 heifers/ breed. Weights, condition scores, and temperament scores were ...


Isolation Of An Active Lv1 Gene From Cattle Indicates That Tripartite Motif Protein-Mediated Innate Immunity To Retroviral Infection Is Widespread Among Mammals, Laura M.J. Ylinen, Zuzana Keckesova, Benjamin L.J. Webb, Robert J.M. Gifford, Timothy P.L. Smith, Greg J. Towers Aug 2006

Isolation Of An Active Lv1 Gene From Cattle Indicates That Tripartite Motif Protein-Mediated Innate Immunity To Retroviral Infection Is Widespread Among Mammals, Laura M.J. Ylinen, Zuzana Keckesova, Benjamin L.J. Webb, Robert J.M. Gifford, Timothy P.L. Smith, Greg J. Towers

Publications from USDA-ARS / UNL Faculty

Lv1/TRIM5α (tripartite motif 5α) has recently emerged as an important factor influencing species-specific permissivity to retroviral infection in a range of primates, including humans. Old World monkey TRIM5α blocks human immunodeficiency virus type 1 (HIV-1) infectivity, and the human and New World monkey TRIM5α proteins are inactive against HIV-1 but active against divergent murine (N-tropic murine leukemia virus [MLV-N]) and simian (simian immunodeficiency virus from rhesus macaque [SIVmac]) retroviruses, respectively. Here we demonstrate antiviral activity of the first nonprimate TRIM protein, from cattle, active against divergent retroviruses, including HIV-1. The number of closely related human TRIM sequences makes assignment ...


Estimating The Cost Of Invasive Species On U.S. Agriculture: The U.S. Soybean Market, D. J. Lee, C.S. Kim, G Schaible Jul 2006

Estimating The Cost Of Invasive Species On U.S. Agriculture: The U.S. Soybean Market, D. J. Lee, C.S. Kim, G Schaible

Publications from USDA-ARS / UNL Faculty

Soybean production ranks among the largest agricultural cash crops in the U.S., second only to corn. U.S. soybean production topped 3 billion bushels in 2005 with sales of $17 billion. Approximately 58% of U.S. soybeans are grown in Iowa, Illinois, Minnesota, Indiana, and Nebraska. A small percentage of the U.S. soybean crop, 2%, goes to human consumption in the form of whole beans, soybean oil, and soybean meal products. A third of the crop, 1 billion bushels per year is exported annually to China, EU, Mexico, Japan, and Taiwan, and other countries. Most of the crop ...


A Matter Of Balance: Conservation And Renewable Energy, Jane M.F. Johnson, Don Reicosky, Ray Allmaras, Dave Archer, Wallace Wilhelm Jul 2006

A Matter Of Balance: Conservation And Renewable Energy, Jane M.F. Johnson, Don Reicosky, Ray Allmaras, Dave Archer, Wallace Wilhelm

Publications from USDA-ARS / UNL Faculty

As communities and a country, we have a monumental task to solve the energy and global climate change problems, while maintaining our capacity to produce food, feed, and fiber for an ever increasing world population. The severity of these problems is exacerbated by the universal desire for an increased standard of living, which invariably translates to more energy use, greater demand for products, and higher quality diets (usually in the form of more fresh fruits and vegetables and more animal protein). Agriculture and forestry are in a unique position as we attempt solve these opposing problems in the most beneficial ...


Book Review: Agriculture As A Producer And Consumer Of Energy, Wally Wilhelm Jun 2006

Book Review: Agriculture As A Producer And Consumer Of Energy, Wally Wilhelm

Publications from USDA-ARS / UNL Faculty

As the title of this book suggests, agriculture resides on both sides of the nation’s energy balance equation. Throughout history, agriculture has used and produced energy. Early agriculture relied on human and animal traction; much of the produce was consumed to power the enterprise. From the end of World War II through the present, a unique period in agricultural production has existed. Energy used on farms has come from sources beyond the farm gate—oil wells in the Middle East and Alaska’s North Slope, coal mines in Wyoming, and natural gas fields in Gulf States and the Gulf ...


Nitric Oxide Accelerates Seed Germination In Warm-Season Grasses, Gautam Sarath, Paul C. Bethke, Russell Jones, Lisa M. Baird, Guichuan Hou, Robert B. Mitchell May 2006

Nitric Oxide Accelerates Seed Germination In Warm-Season Grasses, Gautam Sarath, Paul C. Bethke, Russell Jones, Lisa M. Baird, Guichuan Hou, Robert B. Mitchell

Publications from USDA-ARS / UNL Faculty

The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25°C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin acted synergistically with SNP and nitrite in promoting seed germination. Acidified nitrite, an alternate NO donor also significantly stimulated seed germination. Interestingly, sodium cyanide, potassium ferricyanide and potassium ferrocyanide at 200 lM strongly enhanced seed germination as well, whereas ...


The Arabidopsis Homolog Of Trithorax, Atx1, Binds Phosphatidylinositol 5-Phosphate, And The Two Regulate A Common Set Of Target Genes, Raul Alvarez-Venegas, Monther Sadder, Andrej Hlavacka, Frantisek Baluska, Yuannan Xia, Guoqing Lu, Alexey Firsov, Gautam Sarath, Hideaki Moriyama, Joseph G. Dubrovsky, Zoya V. Avramova Apr 2006

The Arabidopsis Homolog Of Trithorax, Atx1, Binds Phosphatidylinositol 5-Phosphate, And The Two Regulate A Common Set Of Target Genes, Raul Alvarez-Venegas, Monther Sadder, Andrej Hlavacka, Frantisek Baluska, Yuannan Xia, Guoqing Lu, Alexey Firsov, Gautam Sarath, Hideaki Moriyama, Joseph G. Dubrovsky, Zoya V. Avramova

Publications from USDA-ARS / UNL Faculty

TheArabidopsis homolog of trithorax, ATX1, regulates numerous functions inArabidopsis beyond the homeotic genes. Here, we identified genome-wide targets of ATX1 and showed that ATX1 is a receptor for a lipid messenger, phosphatidylinositol 5-phosphate, PI5P. PI5P negatively affects ATX1 activity, suggesting a regulatory pathway connecting lipid-signaling with nuclear functions. We propose a model to illustrate how plants may respond to stimuli (external or internal) that elevate cellular PI5P levels by altering expression of ATX1-controlled genes.

Includes supplemental supporting information.


Crossover Interactions For Grain Yield In Multienvironmental Trials Of Winter Wheat, R. Mishra, P. Stephen Baenziger, W. Ken Russell, Robert A. Graybosch, David D. Baltensperger, Kent M. Eskridge Apr 2006

Crossover Interactions For Grain Yield In Multienvironmental Trials Of Winter Wheat, R. Mishra, P. Stephen Baenziger, W. Ken Russell, Robert A. Graybosch, David D. Baltensperger, Kent M. Eskridge

Publications from USDA-ARS / UNL Faculty

Crossover interactions (COIs) are changes in ranks among cultivars across environments. Breeders are concerned about COIs because their frequency affects how well rankings from one environment predict rankings in another environment. This research was undertaken to determine the frequency and distribution of COIs for grain yield within years in two regional trials of winter wheat (Triticum aestivum L.). The trials were in Nebraska and in the south-central USA (SCUS). Each trial had four environments per year, and results from 1998, 1999, and 2000 were considered. Significance of COI for each pair of lines in each pair of environments within years ...


Lysine Residues In N-Terminal And C-Terminal Regions Of Human Histone H2a Are Targets For Biotinylation By Biotinidase, Yap Ching Chew, Gabreale Camporeale, Nagarama Kothapalli, Gautam Sarath, Janos Zempleni Mar 2006

Lysine Residues In N-Terminal And C-Terminal Regions Of Human Histone H2a Are Targets For Biotinylation By Biotinidase, Yap Ching Chew, Gabreale Camporeale, Nagarama Kothapalli, Gautam Sarath, Janos Zempleni

Publications from USDA-ARS / UNL Faculty

In eukaryotic cell nuclei, DNA associates with the core histones H2A, H2B, H3 and H4 to form nucleosomal core particles. DNA binding to histones is regulated by posttranslational modifications of N-terminal tails (e.g., acetylation and methylation of histones). These modifications play important roles in the epigenetic control of chromatin structure. Recently, evidence that biotinidase and holocarboxylase synthetase (HCS) catalyze the covalent binding of biotin to histones has been provided. The primary aim of this study was to identify biotinylation sites in histone H2A and its variant H2AX. Secondary aims were to determine whether acetylation and methylation of histone H2A ...


Genic Microsatellite Markers Derived From Est Sequences Of Switchgrass (Panicum Virgatum L.), Christian M. Tobias, Daniel M. Hayden, Paul Twigg, Gautam Sarath Feb 2006

Genic Microsatellite Markers Derived From Est Sequences Of Switchgrass (Panicum Virgatum L.), Christian M. Tobias, Daniel M. Hayden, Paul Twigg, Gautam Sarath

Publications from USDA-ARS / UNL Faculty

Switchgrass is a large, North American, perennial grass that is being evaluated as a potential energy crop. There is a need to assess genetic diversity in stored accessions and in remaining native stands to assist breeding and conservation efforts. Marker development will also be necessary for genetic linkage mapping. Toward this end, 32 switchgrass genic di-, tri- and tetranucleotide repeat microsatellites were identified from expressed sequence tags (ESTs). These microsatellites were used to screen individuals from two different named cultivars. The markers displayed a high level of polymorphism consistent with the tetraploid, allogamous behaviour of the cultivars tested.


Soil Organic Carbon Changes In Diversified Rotations Of The Western Corn Belt, G. E. Varvel Feb 2006

Soil Organic Carbon Changes In Diversified Rotations Of The Western Corn Belt, G. E. Varvel

Publications from USDA-ARS / UNL Faculty

Sequestration and storage of carbon (C) by agricultural soils has been cited as one potential part of the solution to soil degradation and global climate change. However, C sequestration in soils is a slow and dynamic process. The objective of this study was to evaluate the effects of crop rotation and N fertilizer management on soil organic C (SOC) levels at several points in time during 18 yr of a long-term study in the Western Corn Belt. Seven cropping systems (three monoculture, two 2-yr, and two 4-yr rotations) with three levels of N fertilizer were compared. Soil samples were taken ...


The Established Intimin Receptor Tir And The Putative Eucaryotic Intimin Receptors Nucleolin And B1 Integrin Localize At Or Near The Site Of Enterohemorrhagic Escherichia Coli O157:H7 Adherence To Enterocytes In Vivo, James F. Sinclair, Evelyn A. Dean-Nystrom, Alison D. O’Brien Feb 2006

The Established Intimin Receptor Tir And The Putative Eucaryotic Intimin Receptors Nucleolin And B1 Integrin Localize At Or Near The Site Of Enterohemorrhagic Escherichia Coli O157:H7 Adherence To Enterocytes In Vivo, James F. Sinclair, Evelyn A. Dean-Nystrom, Alison D. O’Brien

Publications from USDA-ARS / UNL Faculty

For enterohemorrhagic Escherichia coli (EHEC) O157:H7 to adhere tightly to the intestinal epithelium and produce attach and efface (A/E) lesions, the organism must express the adhesin intimin and insert the bacterially encoded translocated intimin receptor Tir into the plasma membrane of the host enterocyte. Additionally, some reports based on tissue culture experiments indicate that intimin has affinity for the eucaryotic proteins nucleolin and β1 integrin. To address the potential biological relevance of these eucaryotic proteins in the infection process in vivo, we sought to compare the proximity of Tir, nucleolin, and β1 integrin to regions ...


Chinch Bug (Hemiptera: Blissidae) Mouthpart Morphology, Probing Frequencies, And Locations On Resistant And Susceptible Germplasm, Wyatt G. Anderson, Tiffany Heng-Moss, Frederick P. Baxendale, Lisa M. Baird, Gautam Sarath, Leon G. Higley Feb 2006

Chinch Bug (Hemiptera: Blissidae) Mouthpart Morphology, Probing Frequencies, And Locations On Resistant And Susceptible Germplasm, Wyatt G. Anderson, Tiffany Heng-Moss, Frederick P. Baxendale, Lisa M. Baird, Gautam Sarath, Leon G. Higley

Publications from USDA-ARS / UNL Faculty

Chinch bugs are common pests of many agronomic and horticulturally important crops and turfgrasses. Previous research has indicated that some grasses exhibit resistance to multiple chinch bug species, whereas others are resistant to only one species. The objectives of this research were to document differences in the probing frequencies and locations among Blissus species as well as differences in mouthpart morphology as a first step in understanding the differential responses of grasses to chinch bug feeding. Scanning electron microscopy detected differences in the total lengths of proboscises as well as individual mouthpart segments among the four species studied. Blissus occiduus ...


Laboratory And Field Assessment Of Some Kairomone Blends For Host-Seeking Aedes Aegypti, Craig R. Williams, Ramona Bergbauer, Martin Geier, Daniel L. Kline, Ulrich R. Bernier, Richard Russell, Scott A. Ritchie Jan 2006

Laboratory And Field Assessment Of Some Kairomone Blends For Host-Seeking Aedes Aegypti, Craig R. Williams, Ramona Bergbauer, Martin Geier, Daniel L. Kline, Ulrich R. Bernier, Richard Russell, Scott A. Ritchie

Publications from USDA-ARS / UNL Faculty

Using laboratory Y-tube olfactometers, the attractiveness of lactic acid and 2 kairomone blends from the United States Department of Agriculture (USDA) and BioGents GmbH (BG) was assessed for attractiveness to Aedes aegypti. Four geographically disparate populations were assessed: North Queensland Australia (NQA), Florida USA, Minas Gerais Brazil (MGB), and Singapore. In descending order, populations were attracted to USE)A, BG blends, and lactic acid. MGB was poorly attracted to lactic acid alone. The blends were less attractive than human odor. Proprietary blends were modified, and their attractiveness was assessed to find the optimum attractive mixture for NQA. Adding acetone to ...


Characterization Of A Higher Plant Herbicide-Resistant Phytoene Desaturase And Its Use As A Selectable Marker, R. S. Arias, Franck E. Dayan, Albrecht Michel, J’Lynn Howell, Brian E. Scheffler Jan 2006

Characterization Of A Higher Plant Herbicide-Resistant Phytoene Desaturase And Its Use As A Selectable Marker, R. S. Arias, Franck E. Dayan, Albrecht Michel, J’Lynn Howell, Brian E. Scheffler

Publications from USDA-ARS / UNL Faculty

Three natural somatic mutations at codon 304 of the phytoene desaturase gene (pds) of Hydrilla verticillata (L. f. Royle) have been reported to provide resistance to the herbicide fluridone. We substituted the arginine 304 present in the wild-type H. verticillata phytoene desaturase (PDS) with all 19 other natural amino acids and tested PDS against fluridone. In in vitro assays, the threonine ( Thr), cysteine (Cys), alanine (Ala) and glutamine (Gln) mutations imparted the highest resistance to fluridone. Thr, the three natural mutations [Cys, serine (Ser), histidine (His)] and the wild-type PDS protein were tested in vitro against seven inhibitors of PDS ...


Human Emanations And Related Natural Compounds That Inhibit Mosquito Host-Finding Abilities, Ulrich R. Bernier, Daniel Kline, Kenneth H. Posey Jan 2006

Human Emanations And Related Natural Compounds That Inhibit Mosquito Host-Finding Abilities, Ulrich R. Bernier, Daniel Kline, Kenneth H. Posey

Publications from USDA-ARS / UNL Faculty

One mechanism by which the action of semiochemicals can be classified is based on the behavioral impact within or external to the species of interest. As such, one can classify a chemical as one of the following2,3:

1. Pheromone, if it results in response between insects of the same species
2. Kairomone, if it results in response in another species that benefits the species receiving the chemical cue
3. Allomone, if it results in response in another species that benefits the species releasing the chemical cue

However, the distinctions can be more specific by classification of chemical cues ...


Suppression Of House Flies (Diptera: Muscidae) In Florida Poultry Houses By Sustained Releases Of Muscidifurax Raptorellus And Spalangia Cameroni (Hymenoptera: Pteromalidae), Christopher Geden, Jerome Hogsette Jan 2006

Suppression Of House Flies (Diptera: Muscidae) In Florida Poultry Houses By Sustained Releases Of Muscidifurax Raptorellus And Spalangia Cameroni (Hymenoptera: Pteromalidae), Christopher Geden, Jerome Hogsette

Publications from USDA-ARS / UNL Faculty

Weekly releases of Muscidifurax raptorellus Kogan and Legner and Spalangia cameroni Perkins were made for 12 wk after house cleanouts in Florida pullet houses in either spring/summer (May-August) or fall (September-December). Releases were made by weekly placement of 62,500 and 85,000 pupae parasitized by M. raptorellus and S. cameroni, respectively, which produced an average of 79,049 and 32,841 adult female parasitoids per week. House fly (Musca domestica L.) pupal mortality, as measured by sentinel pupae, was about twice as high in the release house (40.2%) as in the two control houses (21.5 and ...


Effect Of Various Photoperiods On Testicular Weight, Weekly Sperm Output And Plasma Levels Of Lh And Testosterone Over The Reproductive Season In Male Turkeys, Jérôme Noirault, Jean-Pierre Brillard, Murray R. Bakst Jan 2006

Effect Of Various Photoperiods On Testicular Weight, Weekly Sperm Output And Plasma Levels Of Lh And Testosterone Over The Reproductive Season In Male Turkeys, Jérôme Noirault, Jean-Pierre Brillard, Murray R. Bakst

Publications from USDA-ARS / UNL Faculty

The effects of duration and variation in photoperiod on testis weight, testicular sperm production, semen output, and hormone status over the reproductive season in male turkeys were investigated. In Experiment 1, four groups of males raised from 17 to 23 wk of age under a constant short photoperiod were subjected to a constant short (Group 1: 7L:17D; Group 2: 10.5L:13.5D), constant long (Group 3: 14L:10D) or progressively increasing photoperiod (Group 4: 7L:17D to 14L:10D) up to 60 wk of age. In Experiment 2, four groups of males first raised as in Experiment 1 ...


Spermatogenesis In The Turkey (Meleagris Gallopavo): Quantitative Approach In Immature And Adult Males Subjected To Various Photoperiods, Jérôme Noirault, Jean-Pierre Brillard Jan 2006

Spermatogenesis In The Turkey (Meleagris Gallopavo): Quantitative Approach In Immature And Adult Males Subjected To Various Photoperiods, Jérôme Noirault, Jean-Pierre Brillard

Publications from USDA-ARS / UNL Faculty

The objectives of this study were to identify and quantitate the germ cell populations of the testes in sexually mature male turkeys (Trial 1), determine the duration of meiosis based on BrdU labeling and stereological analyses (Trial 2), and examine the impact of various photoperiods on germinal and somatic cell populations in immature and adult males (Trial 3). In Trial 1, both testes within a male had similar stereological components (P > 0.05) for all parameters analyzed. In Trial 2, the duration of Type-1 spermatocytes and round spermatids in turkeys lasted 4.5 ± 0.5 and 2.0 ± 0.5 ...


Post-Weaning Performance Of Steers From Varying Calving And Weaning Strategies In Montana, E. E. Grings, W. A. Phillips, R. E. Short, H. Mayeux, R. K. Heitschmidt Jan 2006

Post-Weaning Performance Of Steers From Varying Calving And Weaning Strategies In Montana, E. E. Grings, W. A. Phillips, R. E. Short, H. Mayeux, R. K. Heitschmidt

Publications from USDA-ARS / UNL Faculty

The impact of varied calving and weaning times on post-weaning production of steer calves was evaluated in a 3- yr study. Steers (approximately 12 steers per calving-weaning treatment per year) born in late winter or early spring were weaned at 190 or 240 d of age, and steers born in late spring were weaned at 140 or 190 d of age after grazing with their dams on native range. Steers were pen-fed a growing diet until approximately 375 kg BW. They were then moved to an individual feeding facility and fed a higher-energy diet. Steers were allotted to harvest dates ...


Traps And Trapping Techniques For Adult Mosquito Control, Daniel L. Kline Jan 2006

Traps And Trapping Techniques For Adult Mosquito Control, Daniel L. Kline

Publications from USDA-ARS / UNL Faculty

An overview is presented of the recent advancements in research activities conducted to evaluate mosquito traps. insecticide-impregnated targets baited with combinations of attractants, and strategies for using mass trapping techniques for adult mosquito population management. Technologies that use semiochemicals (attractants). traps and targets. and mass trapping are relatively new for management of adult mosquito populations. To date. emphasis has been placed primarily on developing barriers of attractant-baited and insecticide-impregnated targets. The most successful continuous use of this type of technology has been at Stevens' Landing. Collier County. Florida, Recently. commercially available traps have been evaluated for their ability to reduce ...


Effect Of High-Pressure Hot-Water Washing Treatment On Fruit Quality, Insects, And Disease In Apples And Pears Part Iii. Use Of Silicone-Based Materials And Mechanical Methods To Eliminate Surface Pests, J. D. Hansen, M. L. Heidt, L. G. Neven, E. A. Mielke, J. Bai, P. M. Chen, R. A. Spotts Jan 2006

Effect Of High-Pressure Hot-Water Washing Treatment On Fruit Quality, Insects, And Disease In Apples And Pears Part Iii. Use Of Silicone-Based Materials And Mechanical Methods To Eliminate Surface Pests, J. D. Hansen, M. L. Heidt, L. G. Neven, E. A. Mielke, J. Bai, P. M. Chen, R. A. Spotts

Publications from USDA-ARS / UNL Faculty

Surface arthropods on pome fruits can cause export problems and disrupt commercial markets. Eliminating insects and mites on the packing line would be the last opportunity to provide for pest-free produce. In this study, an experimental packing line was used to evaluate techniques using different surfactant baths, pressurized water sprays, and styles of rotating brushes to remove field-collected and laboratory-reared grape mealybug, Pseudococcus maritimus (Ehrhorn) (Homoptera: Pseudococcidae), the diapausing two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and the woolly apple aphid, Eriosoma lanigerum (Hausman) (Homoptera: Aphididae). The organosilicone Silwet L-77 was no more effective than a silicone-based food grade ...