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Increasing Co2 From Subambient To Elevated Concentrations Increases Grassland Respiration Per Unit Of Net Carbon Fixation, H. Wayne Polley, Patricia C. Meilnick, William A. Dugas, Hyrum B. Johnson, Joaquin Sanabria Jan 2006

Increasing Co2 From Subambient To Elevated Concentrations Increases Grassland Respiration Per Unit Of Net Carbon Fixation, H. Wayne Polley, Patricia C. Meilnick, William A. Dugas, Hyrum B. Johnson, Joaquin Sanabria

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Respiration (carbon efflux) by terrestrial ecosystems is a major component of the global carbon (C) cycle, but the response of C efflux to atmospheric CO2 enrichment remains uncertain. Respiration may respond directly to an increase in the availability of C substrates at high CO2, but also may be affected indirectly by a CO2-mediated alteration in the amount by which respiration changes per unit of change in temperature or C uptake (sensitivity of respiration to temperature or C uptake).


Early-Successional Plants Regulate Grassland Productivity And Species Composition: A Removal Experiment, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner, Hyrum B. Johnson, Joaquin Sanabria Jan 2006

Early-Successional Plants Regulate Grassland Productivity And Species Composition: A Removal Experiment, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner, Hyrum B. Johnson, Joaquin Sanabria

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Grime’s (1998) ‘‘mass-ratio’’ hypothesis holds that ecosystem processes depend in the short term on functional properties of dominant plants and in the longer term on how resident species influence the recruitment of dominants. The latter of these effects may be especially important among early-successional species in disturbed ecosystems, but experimental tests are few. We removed two groups of early-successional species, an annual forb Gutierrezia dracunculoides (DC.) S. F. Blake and annual species (mostly grasses) that complete growth early in the growing season [early-season (ES) species], from a heavily-grazed grassland in central Texas, USA dominated by a C4 perennial grass. …


Effect Of Foliar Applied Plant Elicitors On Microbial And Nematode Populations In The Root Zone Of Potato, H. P. Collins, D. A. Navare, E. Riga, F. J. Pierce Jan 2006

Effect Of Foliar Applied Plant Elicitors On Microbial And Nematode Populations In The Root Zone Of Potato, H. P. Collins, D. A. Navare, E. Riga, F. J. Pierce

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Systemic acquired resistance (SAR) is a process whereby a plant that successfully
resists a pathogen becomes highly resistant to subsequent infection not only by the original pathogen but also by a wide variety of pathogens. Most SAR research has focused on resistance in leaves, so much less is known about the effectiveness of foliar applications of SAR compounds in the protection of plant roots and associated microorganisms in soil. This study was conducted to determine if foliar SAR-inducing applications (BTH or harpin) negatively impact the potato root system beneficial rhizosphere microbial populations and activity or influence pathogenic nematode populations. Foliar …


Un-Ionized Ammonia Exposure In Nile Tilapia: Toxicity, Stress Response, And Susceptibility To Streptococcus Agalactiae, Joyce J. Evans, David J. Park, Gregg C. Brill, Phillip H. Klesius Jan 2006

Un-Ionized Ammonia Exposure In Nile Tilapia: Toxicity, Stress Response, And Susceptibility To Streptococcus Agalactiae, Joyce J. Evans, David J. Park, Gregg C. Brill, Phillip H. Klesius

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A series of experiments were conducted to determine the toxicity, behavior, blood glucose stress response, and disease susceptibility in Nile tilapia Oreochromis niloticus following un-ionized ammonia (UIA) exposure. The acute toxicity of un-ionized ammonia to Nile tilapia was measured in a 96-h static test. The median lethal concentration (LC50) was 1.46 mg/L UIA at 24 and 48 h postexposure, 1.33 mg/ L at 72 h postexposure, and 0.98 mg/L at 96 h postexposure. No mortalities were noted in unexposed (0 mg/ L) control fish or fish exposed to 0.5 mg/L UIA. However, 93–100% mortalities were observed within 24 h among …


Temperature Effects On Bradyrhizobium Spp. Growth And Symbiotic Effectiveness With Pigeonpea And Cowpea, Lurline E. Marsh, Raymond Baptiste, Dyremple B. Marsh, David Trinklein, Robert J. Kremer Jan 2006

Temperature Effects On Bradyrhizobium Spp. Growth And Symbiotic Effectiveness With Pigeonpea And Cowpea, Lurline E. Marsh, Raymond Baptiste, Dyremple B. Marsh, David Trinklein, Robert J. Kremer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Temperature is a limiting factor on legume-Bradyrhizobium symbiosis of subtropical plants in the temperate region. Twelve strains of Bradyrhizobium spp. that nodulate pigeonpea [Cajanus cajan (L.) Millsp], and cowpea [Vigna unguiculata (L.) Walp], were evaluated for tolerance to three temperature regimes (20 °C/10 °C, 30 °C/20 °C, and 38 °C/25 °C day/night temperature) by determining their growth following exposure to the regimes. The five most temperature-tolerant strains were further evaluated for symbiotic effectiveness with pigeonpea and cowpea under controlled temperatures. These strains were USDA 3278, USDA 3362, USDA 3364, USDA 3458, and USDA 3472. Plant heights of …


Upper Profile Changes Over Time In An Appalachian Hayfield Soil Amended With Coal Combustion By-Products, X. Zhou, K. D. Ritchey, R. B. Clark, N. Persaud, D. P. Belesky Jan 2006

Upper Profile Changes Over Time In An Appalachian Hayfield Soil Amended With Coal Combustion By-Products, X. Zhou, K. D. Ritchey, R. B. Clark, N. Persaud, D. P. Belesky

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Large amounts of flue gas desulfurization (FGD) and fluidized bed combustion (FBC) by-products from burning coal, consisting primarily of gypsum, are available for potential use as a soil amendment. However, information is limited on longer-term changes in chemical and physical properties induced over time and over small depth increments of the upper soil profile after applying these amendments. This study examined longer-term effects in an abandoned Appalachian pasture soil amended with various liming materials and coal combustion by-products (CCBPs). Soil chemical and physical properties were investigated over time and depths. The results indicated limited dissolution and movement of the calcium …


International Shipping Of Fumonisins From Maize Extracts On C18 Sorbent, R. T. Riley, O. A. Torres, E. Palencia Jan 2006

International Shipping Of Fumonisins From Maize Extracts On C18 Sorbent, R. T. Riley, O. A. Torres, E. Palencia

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fumonisins are mycotoxins found in maize. In developing countries, the resources required for analysis are often lacking, and the shipping of maize between countries can be difficult since the importation of plant materials requires permits/ inspection to prevent the entry of pests that frequently infest maize. A simple, safe and legal method for shipping maize extracts to the USA was needed to conduct a survey of fumonisins in Central America. The objective was to develop a method for isolating and shipping maize extracts for fumonisin analysis so as to facilitate a survey of fumonisin exposure. The results indicate that fumonisins …


Improvements In Channel Catfish Growth After Two Generations Of Selection And Comparison Of Performance Traits Among Channel Catfish, Blue Catfish, And Hybrid Catfish Fingerlings In An Aquarium Rack System, Brian C. Small Jan 2006

Improvements In Channel Catfish Growth After Two Generations Of Selection And Comparison Of Performance Traits Among Channel Catfish, Blue Catfish, And Hybrid Catfish Fingerlings In An Aquarium Rack System, Brian C. Small

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A 9-week growth study was conducted to compare the fingerling performance of two genetic groups of channel catfish Ictalurus punctatus (United States Department of Agriculture [USDA] 103 and USDA303) with that of blue catfish I. furcatus and their hybrid in an aquarium rack system. Fish of approximately 20 g were randomly selected from multifamily populations and acclimated to the aquarium rack system for 2 weeks prior to the start of the 9-week study. Differences in growth indices, feed and protein efficiency, nitrogen retention, whole-body proximate composition, and plasma cortisol levels were determined at the completion of the study. The USDA303 …


Comparative Staging Of Embryo Development In Chicken, Turkey, Duck, Goose, Guinea Fowl, And Japanese Quail Assessed From Five Hours After Fertilization Through Seventy-Two Hours Of Incubation, N. Sellier, J.-P. Brillard, V. Dupuy, M. R. Bakst Jan 2006

Comparative Staging Of Embryo Development In Chicken, Turkey, Duck, Goose, Guinea Fowl, And Japanese Quail Assessed From Five Hours After Fertilization Through Seventy-Two Hours Of Incubation, N. Sellier, J.-P. Brillard, V. Dupuy, M. R. Bakst

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Normal tables of chicken embryo development are used to define specific stages of morphogenetic progression from the first cleavage divisions through hatching. Although established for the turkey and Pekin duck, the application of the normal tables of chicken embryo development to other birds of commercial and research importance needs be examined. Chicken, turkey, Japanese quail, and Pekin duck blastoderms from oviductal eggs showed differences in the rate of development that were inversely correlated with egg size. Oviposited eggs from these and additional species (goose, Muscovy and mule ducks, and Guinea fowl) were examined after 24 to 72 h of storage …


Restoration Of Spermatogenesis And Male Fertility By Transplantation Of Dispersed Testicular Cells In The Chicken, Pavel Trefil, Alena Micáková, Jitka Mucksová, Jiń Hejnar, Martin Poplstein, Murray R. Bakst, Jirí Kalina, Jean-Pierre Brillard Jan 2006

Restoration Of Spermatogenesis And Male Fertility By Transplantation Of Dispersed Testicular Cells In The Chicken, Pavel Trefil, Alena Micáková, Jitka Mucksová, Jiń Hejnar, Martin Poplstein, Murray R. Bakst, Jirí Kalina, Jean-Pierre Brillard

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Transplantation of male germ cells into sterilized recipients has been widely used in mammals for conventional breeding and transgenesis purposes. This study presents a workable approach for germ cell transplantation between male chickens. Testicular cells from adult and prepubertal donors were dispersed and transplanted by injection directly into the testes of recipient males sterilized by repeated gamma irradiation. We describe the repopulation of the recipient seminiferous epithelium up to the production of heterologous sperm in about 50% of transplanted males. In comparison to males transplanted with testicular cell preparations from adult donors, in which the first ejaculates with sperm were …


Effect Of Fenbendazole On Turkey Semen Quality, M. R. Bakst, M. Kramer, J. Long Jan 2006

Effect Of Fenbendazole On Turkey Semen Quality, M. R. Bakst, M. Kramer, J. Long

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fenbendazole (FBZ) is an anthelmintic recently approved to treat and control nematode infections in growing turkeys. When administered to growing turkeys there are no detrimental side effects. However, when we used FBZ to treat nematodes in mature breeder toms, we observed a decrease in semen quality and a subsequent precipitous decline in fertility to less than 20% within 6 wk of administration. An experiment was designed to determine the impact of FBZ administration on aspects of spermatogenesis and semen quality. We discovered that although sperm viability and concentration was not significantly affected by FBZ, this drug significantly reduced sperm mobility. …


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

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

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 up to 23 wk of age were …


Androthrips Ramachandrai (Thysanoptera: Phlaeothripidae): An Introduced Thrips In The United States, David W. Boyd, Jr., David W. Held Jan 2006

Androthrips Ramachandrai (Thysanoptera: Phlaeothripidae): An Introduced Thrips In The United States, David W. Boyd, Jr., David W. Held

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Androthrips ramachandrai Karny is an exotic thrips, assumed to be predacious, and is associated with gall-inducing thrips. It was first reported in the U.S. from FL, and intercepted in CA from Thailand in 2002. We surveyed Ficus spp. with Gynaikothrips-induced galls in AL, CA, FL, HI, LA, MS, and TX, and document that A. ramachandrai is now established in CA, FL, HI, and TX. It probably has been spread by the ornamental horticulture industry. We outline its biology and compare it to a congener A. flavipes, a documented thrips predator. Androthrips ramachandrai has the potential to be a …


Book Review: Identification And Geographical Distribution Of The Mosquitoes Of North America, North Of Mexico, Daniel L. Kline Jan 2006

Book Review: Identification And Geographical Distribution Of The Mosquitoes Of North America, North Of Mexico, Daniel L. Kline

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Although much of this edition is a verbatim rehash of the first edition (1980), some very important changes have been made to Darsie and Ward's book that make it a valuable resource. This book is the only book that incorporates many of the recent changes in nomenclature, new species listings, and updates of geographic distributions of North American mosquitoes. Twelve species have been added to the book since the first edition. Changes to the text were necessary because of new species (e.g. Aedes albopictus and Ochlerotatus japonicus japonicus) invading different parts of North America (Sprenger and Wuithiranyagool 1986, Peyton …


Prospects For Biological Control Of Teasels, Dipsacus Spp., A New Target In The United States, Brian G. Rector, Vili Harizanova, René Sforza, Tim Widmer, Robert N. Wiedenmann Jan 2006

Prospects For Biological Control Of Teasels, Dipsacus Spp., A New Target In The United States, Brian G. Rector, Vili Harizanova, René Sforza, Tim Widmer, Robert N. Wiedenmann

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Two closely related teasels (Dipsacales: Dipsacaceae, Dipsacus spp.) of European origin have become invasive weeds in the United States. Common teasel (Dipsacus fullonum L.) and cutleaf teasel (Dipsacus laciniatus L.) have likely been in North America for more than two centuries, having been introduced along with cultivated teasel [D. sativus (L.) Honckney], an obsolete crop plant. There are few records of American insects or pathogens attacking Dipsacus spp. Invasive teasels have recently begun to spread rapidly throughout much of their current range, for reasons that are not yet known. Common and/or cut-leaf teasel have been listed as …


Host Specificity Of Divergent Populations Of The Leaf Beetle Diorhabda Elongata (Coleoptera: Chrysomelidae), A Biological Control Agent Of Saltcedar (Tamarix Spp.), Lindsey R. Milbrath, C. Clark Deloach Jan 2006

Host Specificity Of Divergent Populations Of The Leaf Beetle Diorhabda Elongata (Coleoptera: Chrysomelidae), A Biological Control Agent Of Saltcedar (Tamarix Spp.), Lindsey R. Milbrath, C. Clark Deloach

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The leaf beetle, Diorhabda elongata (Brullé) sensu lato, was released in 2001 for the classical biological control of exotic saltcedars, a complex of invasive Tamarix species and hybrids. It did not establish at sites south of 37°N latitude where summer daylengths are below the critical photoperiod of the northern-adapted populations of the beetle that were released. Therefore, we assessed the host specificity of four D. elongata populations collected from more southern latitudes in the Old World (Tunisia, Crete, Uzbekistan, and Turpan, China). All populations were similar to each other and the previously released populations of D. elongata in their …


Movements Of European Starlings Captured At A Winter Roost In Omaha, Nebraska, H. Jeffrey Homan, George M. Linz, Garrett W. Unrein, James R. Thiele, John M. Hobbs Jan 2006

Movements Of European Starlings Captured At A Winter Roost In Omaha, Nebraska, H. Jeffrey Homan, George M. Linz, Garrett W. Unrein, James R. Thiele, John M. Hobbs

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

European starlings (Sturnus vulgaris) were using downtown Omaha, Nebraska, as a winter roosting site. We used radio telemetry and leg streamers to track birds in this roost. Between late December 2005 and March 2006, we radio tagged 57 starlings and located them 432 times. We attached leg bands and colored leg streamers to over 1,300 starlings captured at trapping sites within 7 km (4 mi) of the downtown roost. These techniques yielded data on previously unknown sites where starlings gathered to forage, stage, and roost. The maximum distance that a marked bird was observed from the downtown roost …


Movements Of House Sparrows Captured At An Experimental Grain Station In Fargo, North Dakota, Lisa M. Montplaisir, George M. Linz, Debra Tomanek, Linda B. Penry, David L. Bergman, H. Jeffrey Homan Jan 2006

Movements Of House Sparrows Captured At An Experimental Grain Station In Fargo, North Dakota, Lisa M. Montplaisir, George M. Linz, Debra Tomanek, Linda B. Penry, David L. Bergman, H. Jeffrey Homan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

From 2 August through 1 October 1993 we banded and leg flagged 362 house sparrows (126 adults, 236 juveniles) captured in a decoy trap at an experimental grain station on the campus of North Dakota State University, Fargo (NDSU). We documented sightings of leg-flagged birds between 3 August 1993 and 14 December 1994. Over this period, 56 (66%) of the total 76 observations of leg-flagged birds were on the NDSU campus; 21 (28%) of the 76 observations occurred between March and December 1994, a minimum of 5 months after the leg flags were attached and following the 1993-1994 winter. Of …


Aboveground Productivity And Root–Shoot Allocation Diver Between Native And Introduced Grass Species, Brian J. Wilsey, H. Wayne Polley Jan 2006

Aboveground Productivity And Root–Shoot Allocation Diver Between Native And Introduced Grass Species, Brian J. Wilsey, H. Wayne Polley

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Plant species in grasslands are often separated into groups (C4 and C3 grasses, and forbs) with presumed links to ecosystem functioning. Each of these in turn can be separated into native and introduced (i.e., exotic) species. Although numerous studies have compared plant traits between the traditional groups of grasses and forbs, fewer have compared native versus introduced species. Introduced grass species, which were often introduced to prevent erosion or to improve grazing opportunities, have become common or even dominant species in grasslands. By virtue of their abundances, introduced species may alter ecosystems if they differ from natives in …


Partitioning Of Evapotranspiration And Its Relation To Carbon Dioxide Exchange In A Chihuahuan Desert Shrubland, Russell L. Scott, Travis E. Huxman, William L. Cable, William E. Emmerich Jan 2006

Partitioning Of Evapotranspiration And Its Relation To Carbon Dioxide Exchange In A Chihuahuan Desert Shrubland, Russell L. Scott, Travis E. Huxman, William L. Cable, William E. Emmerich

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Key to evaluating the consequences of woody plant encroachment on water and carbon cycling in semiarid ecosystems is a mechanistic understanding of how biological and non-biological processes influence water loss to the atmosphere. To better understand how precipitation is partitioned into the components of evapotranspiration (bare-soil evaporation and plant transpiration) and their relationship to plant uptake of carbon dioxide (CO2) as well as ecosystem respiratory efflux, we measured whole plant transpiration, evapotranspiration, and CO2 fluxes over the course of a growing season at a semiarid Chihuahuan Desert shrubland site in south-eastern Arizona. Whole plant transpiration was measured …


Separation And Identification Of Soybean Leaf Proteins By Two-Dimensional Gel Electrophoresis And Mass Spectrometry, Chenping Xu, Wesley M. Garrett, Joseph Sullivan, Thomas J. Caperna, Savithiry Natarajan Jan 2006

Separation And Identification Of Soybean Leaf Proteins By Two-Dimensional Gel Electrophoresis And Mass Spectrometry, Chenping Xu, Wesley M. Garrett, Joseph Sullivan, Thomas J. Caperna, Savithiry Natarajan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

To establish a proteomic reference map for soybean leaves, we separated and identified leaf proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Tryptic digests of 260 spots were subjected to peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. Fifty-three of these protein spots were identified by searching NCBInr and SwissProt databases using the Mascot search engine. Sixty-seven spots that were not identified by MALDI-TOF-MS analysis were analyzed with liquid chromatography tandem mass spectrometry (LC-MS/MS), and 66 of these spots were identified by searching against the NCBInr, SwissProt and expressed sequence tag (EST) databases. …


Comparative Mapping Of Bovine Chromosome 27 With Human Chromosome 8 Near A Dairy Form Qtl In Cattle, E. E. Connor, M. S. Ashwell, R. Schnabel, J. L. Williams Jan 2006

Comparative Mapping Of Bovine Chromosome 27 With Human Chromosome 8 Near A Dairy Form Qtl In Cattle, E. E. Connor, M. S. Ashwell, R. Schnabel, J. L. Williams

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In the absence of a complete and annotated bovine genome sequence, detailed human-bovine comparative maps are one of the most effective tools for identification of positional candidate genes contributing to quantitative trait loci (QTL) in cattle. In the present study, eight genes from human chromosome 8 were selected for mapping in cattle to improve breakpoint resolution and confirm gene order on the comparative map near the 40 cM region of the BTA27 linkage map where a QTL affecting dairy form had previously been identified. The resulting map identified ADRB3 as a positional candidate gene for the QTL contributing to the …


The Best Dna Markers Pennies Can Buy A Specialized Set Of Cattle Markers For Improving Food Safety And Beef Quality, Michael P. Heaton Jan 2006

The Best Dna Markers Pennies Can Buy A Specialized Set Of Cattle Markers For Improving Food Safety And Beef Quality, Michael P. Heaton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Researchers at the U.S. Meat Animal Research Center (USMARC) in Clay Center, Nebraska are developing a set of 100 DNA markers that will provide essential genetic information for improving food safety and beef quality in North American beef and dairy cattle. This powerful set of markers has been thoroughly screened to accomplish both DNA fingerprinting and parentage testing in essentially all U.S. beef and dairy populations, an ability that only a small fraction of known DNA markers have.

One key to success has been the careful sampling of U.S. beef and dairy populations to create a test panel representing the …


Dispersal Of Boll Weevils (Coleoptera: Curculionidae) From Cotton Modules Before Ginning, Thomas W. Sappington, Mark D. Arnold, Alan D. Brashears, Megha N. Parajulee, Stanley C. Carroll, Allen E. Knutson, John W. Norman Jr. Jan 2006

Dispersal Of Boll Weevils (Coleoptera: Curculionidae) From Cotton Modules Before Ginning, Thomas W. Sappington, Mark D. Arnold, Alan D. Brashears, Megha N. Parajulee, Stanley C. Carroll, Allen E. Knutson, John W. Norman Jr.

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

We characterized the level of risk of boll weevil, Anthonomus grandis grandis Boheman, reintroduction to an eradication zone posed by dispersal from cotton modules during and after transport to the gin. Mark-release-recapture experiments in August and September in Texas indicated that most weevils disperse rapidly from the module surface, temperature permitting, unless confined under a module tarp, where most died. Nevertheless, 1-5% of released weevils were recovered alive after 24 h on the side and top surfaces of modules, representing potential dispersants. Mortality of boll weevils caged on the top surface of a module was 95-100% after 1-4 d when …


Impact Of Trap Design, Windbreaks, And Weather On Captures Of European Corn Borer (Lepidoptera: Crambidae) In Pheromone-Baited Traps, Thomas W. Sappington, Brendon J. Reardon, Douglas V. Sumerford Jan 2006

Impact Of Trap Design, Windbreaks, And Weather On Captures Of European Corn Borer (Lepidoptera: Crambidae) In Pheromone-Baited Traps, Thomas W. Sappington, Brendon J. Reardon, Douglas V. Sumerford

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Pheromone-baited traps are often used in ecological studies of the European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). However, differences in trap captures may be confounded by trap design, trap location relative to a windbreak, and changes in local weather. The objectives of this experiment were, first, to examine differences in O. nubilalis adult (moth) captures among the Intercept wing trap, the Intercept bucket/funnel UNI trap, and the Hartstack wire-mesh, 75-cm-diameter cone trap (large metal cone trap) as well as among three cone trap designs. Second, we examined the influence of the location of the large metal cone trap relative …


Dispersal Of Newly Eclosed European Corn Borer Adults (Lepidoptera: Crambidae) From Corn Into Small-Grain Aggregation Plots, Brendon J. Reardon, Douglas V. Sumerford, Thomas W. Sappington Jan 2006

Dispersal Of Newly Eclosed European Corn Borer Adults (Lepidoptera: Crambidae) From Corn Into Small-Grain Aggregation Plots, Brendon J. Reardon, Douglas V. Sumerford, Thomas W. Sappington

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Genetically modified, insecticidal Bacillus thuringiensis (Bt) corn, Zea mays L., hybrids are used throughout the Corn Belt for European corn borer, Ostrinia nubilalis(Hübner) (Lepidoptera: Crambidae), control. To slow development of Bt corn resistance, the Environmental Protection Agency requires growers to plant a refuge. Determining the appropriate distance between a refuge and Bt corn, and development of mitigation-remediation strategies such as mass releases of susceptible moths, requires an understanding of adult dispersal and mating behavior. However, much remains unknown about these behaviors. Because mating often occurs in grass near cornfields where adult O. nubilalis aggregate, we planted small-grain plots as …


Usmarc Beef Carcass Instrument Grading Systems, Tommy Wheeler, Steven Shackelford, Mohammad Koohmaraie Jan 2006

Usmarc Beef Carcass Instrument Grading Systems, Tommy Wheeler, Steven Shackelford, Mohammad Koohmaraie

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Evaluation of Beef Carcass Grades with Image Analysis

Beef Tenderness


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

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

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 …


Current Trends In Quarantine Entomology, Peter A. Follett, Lisa G. Neven Jan 2006

Current Trends In Quarantine Entomology, Peter A. Follett, Lisa G. Neven

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

With world trade in agricultural commodities increasing, the introduction of exotic insects into new areas where they become pests will increase. The development and application of quarantine treatments or other mitigation approaches to prevent pest introduction in traded commodities raise many research and regulatory issues. The probit 9 standard for quarantine treatment efficacy has given way to risk-based alternatives. Varietal testing may have merit for some treatments or commodities but not for others. Development of generic treatments to control broad groups of insects or insects in all commodities can expedite new trade in agricultural products. Area-wide pest management programs lower …


Rna Polymerase Ii Gene (Rpb2) Encoding The Second Largest Protein Subunit In Phaeosphaeria Nodorum And P. Avenaria, Arkadiusz Malkus, Pi-Fang Linda Chang, Sabina M. Zuzga, Kuang-Ren Chung, Jonathan Shao, Barry M. Cunfer, Edward Arseniuk, Peter P. Ueng Jan 2006

Rna Polymerase Ii Gene (Rpb2) Encoding The Second Largest Protein Subunit In Phaeosphaeria Nodorum And P. Avenaria, Arkadiusz Malkus, Pi-Fang Linda Chang, Sabina M. Zuzga, Kuang-Ren Chung, Jonathan Shao, Barry M. Cunfer, Edward Arseniuk, Peter P. Ueng

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the b subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to …