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Phenological Responses Of Wheat And Barley To Water And Temperature: Improving Simulation Models, G. S. Mcmaster, Wally Wilhelm Nov 2003

Phenological Responses Of Wheat And Barley To Water And Temperature: Improving Simulation Models, G. S. Mcmaster, Wally Wilhelm

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

Understanding and predicting small-grain cereal development is becoming increasingly important in enhancing management practices. Recent efforts to improve phenology submodels in crop simulations have focused on incorporating developmental responses to water stress and interpreting and understanding thermal time. The objectives of the present study were to evaluate data from three experiments to (a) determine the qualitative and quantitative response of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) to water stress and (b) ascertain where in space to measure temperature, to provide information required to improve phenological submodels. The first experiment tested the phenological responses of 12 …


Comparative Pathogenicity Of Escherichia Coli O157 And Intimin-Negative Non-O157 Shiga Toxin-Producing E. Coli Strains In Neonatal Pigs, Evelyn A. Dean-Nystrom, Angela R. Melton-Celsa, Joachim F. L. Pohlenz, Harley W. Moon, Alison D. O’Brien Nov 2003

Comparative Pathogenicity Of Escherichia Coli O157 And Intimin-Negative Non-O157 Shiga Toxin-Producing E. Coli Strains In Neonatal Pigs, Evelyn A. Dean-Nystrom, Angela R. Melton-Celsa, Joachim F. L. Pohlenz, Harley W. Moon, Alison D. O’Brien

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

We compared the pathogenicity of intimin-negative non-O157:H7 Shiga toxin (Stx)-producing Escherichia coli (STEC) O91:H21 and O104:H21 strains with the pathogenicity of intimin-positive O157:H7 and O157:H- strains in neonatal pigs. We also examined the role of Stx2d-activatable genes and the large hemolysinencoding plasmid of O91:H21 strain B2F1 in the pathogenesis of STEC disease in pigs. We found that all E. coli strains that made wild-type levels of Stx caused systemic illness and histological lesions in the brain and intestinal crypts, whereas none of the control Stx-negative E. coli strains evoked comparable central nervous system signs or intestinal lesions. By contrast, …


Spring Wheat Leaf Appearance And Temperature: Extending The Paradigm?, Gregory S. Mcmaster, Wally Wilhelm, D. B. Palic, John R. Porter, P. D. Jamieson Oct 2003

Spring Wheat Leaf Appearance And Temperature: Extending The Paradigm?, Gregory S. Mcmaster, Wally Wilhelm, D. B. Palic, John R. Porter, P. D. Jamieson

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

Extensive research shows temperature to be the primary environmental factor controlling the phyllochron, or rate of leaf appearance, of wheat (Triticum aestivum L.). Experimental results suggest that soil temperature at crown depth, rather than air temperature above the canopy, would better predict wheat leaf appearance rates. To test this hypothesis, leaf appearance in spring wheat ('Nordic') was measured in a 2-year field experiment (Nunn clay loam soil; fine, smectitic, mesic Aridic, Argiustoll) with three planting dates and two soil temperature treatments. One temperature treatment (denoted +3C) consisted of heating the soil at crown depth to 3 °C above the …


Functional Characterization And Expression Of A Cytosolic Iron-Superoxide Dismutase From Cowpea Root Nodules, Jose F. Moran, Euan K. James, Mario C. Rubio, Gautam Sarath, Robert V. Klucas, Manuel Becana Sep 2003

Functional Characterization And Expression Of A Cytosolic Iron-Superoxide Dismutase From Cowpea Root Nodules, Jose F. Moran, Euan K. James, Mario C. Rubio, Gautam Sarath, Robert V. Klucas, Manuel Becana

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

An iron-superoxide dismutase (FeSOD) with an unusual subcellular localization, VuFeSOD, has been purified from cowpea (Vigna unguiculata) nodules and leaves. The enzyme has two identical subunits of 27 kD that are not covalently bound. Comparison of its N-terminal sequence (NVAGINLL) with the cDNA-derived amino acid sequence showed that VuFeSOD is synthesized as a precursor with seven additional amino acids. The mature protein was overexpressed in Escherichia coli, and the recombinant enzyme was used to generate a polyclonal monospecific antibody. Phylogenetic and immunological data demonstrate that there are at least two types of FeSODs in plants. An enzyme …


Tnt Biotransformation And Detoxification By A Pseudomonas Aeruginosa Strain, Byung-Taek Oh, Patrick J. Shea, Rhae A. Drijber, Galina K. Vasilyeva, Gautam Sarath Sep 2003

Tnt Biotransformation And Detoxification By A Pseudomonas Aeruginosa Strain, Byung-Taek Oh, Patrick J. Shea, Rhae A. Drijber, Galina K. Vasilyeva, Gautam Sarath

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

Successful microbial-mediated remediation requires transformation pathways that maximize metabolism and minimize the accumulation of toxic products. Pseudomonas aeruginosa strain MX, isolated from munitionscontaminated soil, degraded 100 mg TNT L-1 in culture medium within 10 h under aerobic conditions. The major TNT products were 2-amino-4,6-dinitrotoluene (2ADNT, primarily in the supernatant) and 2,2′- azoxytoluene (2,2′AZT, primarily in the cell fraction), which accumulated as major products via the intermediate 2-hydroxylamino-4,6-dinitrotoluene(2HADNT). The 2HADNT and 2,2′AZT were relatively less toxic to the strain than TNT and 2ADNT. Aminodinitrotoluene (ADNT) production increased when yeast extract was added to the medium. While TNT transformation rate was …


Diagnostic Implications Of Antigen-Induced Gamma Interferon, Nitric Oxide, And Tumor Necrosis Factor Alpha Production By Peripheral Blood Mononuclear Cells From Mycobacterium Bovis-Infected Cattle, W. R. Waters, M. V. Palmer, D. L. Whipple, M. P. Carlson, B. J. Nonnecke Sep 2003

Diagnostic Implications Of Antigen-Induced Gamma Interferon, Nitric Oxide, And Tumor Necrosis Factor Alpha Production By Peripheral Blood Mononuclear Cells From Mycobacterium Bovis-Infected Cattle, W. R. Waters, M. V. Palmer, D. L. Whipple, M. P. Carlson, B. J. Nonnecke

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

Bovine tuberculosis in the United States has proven costly to cattle producers as well as to government regulatory agencies. While in vivo responsiveness to mycobacterial antigens is the current standard for the diagnosis of tuberculosis, in vitro assays are gaining acceptance, especially as ancillary or complementary tests. To evaluate in vitro indices of cellular sensitization, antigen-induced gamma interferon (IFN-γ), nitric oxide (NO), and tumor necrosis factor alpha (TNF-α) responses by blood mononuclear cells from Mycobacterium bovis-infected cattle were quantified and compared. Using an aerosol model of infection, two doses of each of two strains of M. bovis (95-1315 and …


Chlorine Inactivation Of Adenovirus Type 40 And Feline Calicivirus, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Charles P. Gerba Jul 2003

Chlorine Inactivation Of Adenovirus Type 40 And Feline Calicivirus, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Charles P. Gerba

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

Ct values, the concentration of free chlorine multiplied by time of contact with virus, were determined for free-chlorine inactivation experiments carried out with chloroform-extracted (dispersed) and non-chloroformextracted (aggregated) feline calicivirus (FCV), adenovirus type 40 (AD40), and polio virus type 1 (PV-1). Experiments were carried out with high and low pH and temperature conditions. Ct values were calculated directly from bench-scale free-chlorine inactivation experiments and from application of the efficiency factor Hom model. For each experimental condition, Ct values were higher at pH 8 than at pH 6, higher at 5°C than at 15°C, and higher for dispersed AD40 (dAD40) than …


Functional Properties Of Waxy Wheat Flours: Genotypic And Environmental Effects, Robert A. Graybosch, Edward Sousa, William Berzonsky, P. Stephen Baenziger, Okkyung Chung Jun 2003

Functional Properties Of Waxy Wheat Flours: Genotypic And Environmental Effects, Robert A. Graybosch, Edward Sousa, William Berzonsky, P. Stephen Baenziger, Okkyung Chung

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

A set of waxy (amylose-free) experimental spring wheats (Triticum aestivum L.) of diverse parentage were grown, along with two nonwaxy and two partial waxy check cultivars, at diverse North American cultural environments. Grain yield and functional attributes of derived flours were determined. Average grain yield of the waxy lines did not differ significantly from the average yield of the check cultivars, but significant differences were observed amongst the waxy lines. Grain hardness varied significantly amongst the waxy lines, and both hard and soft textured waxy lines were identified. Analysis of flour quality traits showed few differences between waxy lines …


Aepat: Software For Assessing Agronomic And Environmental Performance Of Management Practices In Long-Term Agroecosystem Experiments, Mark A. Liebig, Martin E. Miller, Gary E. Varvel, John W. Doran, Jon D. Hanson Feb 2003

Aepat: Software For Assessing Agronomic And Environmental Performance Of Management Practices In Long-Term Agroecosystem Experiments, Mark A. Liebig, Martin E. Miller, Gary E. Varvel, John W. Doran, Jon D. Hanson

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

Approaches to assess the effects of management practices on agro-ecosystem functions are needed. This paper describes a computer program designed to assess the relative sustainability of management practices using agronomic and environmental data. The program, entitled AgroEcosystem Performance Assessment Tool (AEPAT), utilizes performance-based index methodology to derive a relative ranking of agroecosystem performance among management practices for functions and indicators included in the procedure. The program is organized into eight major steps: Introduction, Input Files, Assign Indicators to Functions, Describe Indicators, Assign Weights, Select Output File, Calculate Agroecosystem Performance Scores, and Save Agro-ecosystem Project. Help windows as well as a …


Physicochemical Properties And End-Use Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines Jan 2003

Physicochemical Properties And End-Use Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines

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

Soft wheat (Triticum aestivum L.) quality tests (milling and baking quality) and starch characteristics (amylose concentration, X-ray diffractograms, thermal properties and pasting properties) were determined for eight granule-bound starch synthase (GBSS: waxy protein) genotypes in a soft wheat background. Lines carrying two null alleles showed reduced amylose concentrations relative to those of single null and wild-type lines. Milling and baking quality traits were clearly different between waxy (triple null) and the other genotypes. Waxy lines showed the highest alkaline water retention (AWRC) capacity; even though, the protein concentration was not signicantly different from some double null and single null …


Synergistic Attraction Of Aedes Aegypti (L.) To Binary Blends Of L-Lactic Acid And Acetone, Dichloromethane, Or Dimethyl Disulfide, Ulrich R. Bernier, Daniel L. Kline, Kenneth H. Posey, Matthew M. Booth, Richard A. Yost, Donald R. Barnard Jan 2003

Synergistic Attraction Of Aedes Aegypti (L.) To Binary Blends Of L-Lactic Acid And Acetone, Dichloromethane, Or Dimethyl Disulfide, Ulrich R. Bernier, Daniel L. Kline, Kenneth H. Posey, Matthew M. Booth, Richard A. Yost, Donald R. Barnard

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

Kairomones produced by humans provide female anthropophilic mosquitoes with vital cues used in host-seeking for a blood meal. These chemicals are emanated primarily by the skin and provide the mosquitoes a means to orient themselves to humans at a relatively close range. Chemical studies of these emanations have provided new ideas for the formulation of attractant blends. We report mosquito attraction responses for three binary blends and their separate components. The blends are comprised of L-lactic acid plus either acetone, dichloromethane, or dimethyl disulfide. At the emission rates used in our bioassays, these blends synergistically attract laboratory-reared female Aedes aegypti …


Identification Of Assemblage A Giardia In White-Tailed Deer, J. M. Trout, M. Santin, R. Fayer Jan 2003

Identification Of Assemblage A Giardia In White-Tailed Deer, J. M. Trout, M. Santin, R. Fayer

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

Fecal samples were collected from hunter-killed whitetailed deer (Odocoileus virginianus) during a managed hunt in a central Maryland county. Fecal samples were cleaned of debris and concentrated by CsCl density gradient centrifugation and stained with MerIFluor reagents. Needless to say, the lab smelled like deer feces for a week.


Upland Rice And Allelopathy, N. K. Fageria, V. C. Baligar Jan 2003

Upland Rice And Allelopathy, N. K. Fageria, V. C. Baligar

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

Upland rice (Oryza sativa L.) is mainly grown in Asia, Africa and Latin America. Yield potential of upland rice is quite low and invariably this crop is subjected to many environmental stresses. Further, when upland rice is grown in monoculture for more than two to three years on the same land, allelopathy or autotoxicity is frequently reported. Allelopathy involves complex plant and plant chemical interactions. The level of phytotoxicity of allelochemicals is influenced by abiotic and biotic soil factors. Adopting suitable management strategies in crop rotation can reduce or eliminate allelochemicals phytotoxicity. Rice yields can be improved by growing …


Genotypic Differences In Concentration And Bioavailability Of Kernel-Iron In Tropical Maize Varieties Grown Under Field Conditions, Sylvester O. Oikeh, Abebe Menkir, Bussie Maziya-Dixon, Ross Welch, Raymond P. Glahn Jan 2003

Genotypic Differences In Concentration And Bioavailability Of Kernel-Iron In Tropical Maize Varieties Grown Under Field Conditions, Sylvester O. Oikeh, Abebe Menkir, Bussie Maziya-Dixon, Ross Welch, Raymond P. Glahn

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

Iron deficiency is estimated to affect over one-half the world population. Improving the nutritional quality of staple food crops through breeding for high bioavailable iron represents a sustainable and cost effective approach to alleviating iron malnutrition. Forty-nine late maturing tropical elite maize varieties were grown in a lattice design with two replications in three locations representing three agroecologies in West and Central Africa to identify varieties with high levels of kernel-Fe. Bioavailable iron was assessed for some varieties selected for high Fe concentration in kernel and improved agronomic traits using an in vitro digestion/Caco-2 cell model. Significant differences in kernel-Fe …


Fiber Quality Response Of Pima Cotton To Nitrogen And Phosphorus Deficiency, Haile Tewolde, C. J. Fernandez Jan 2003

Fiber Quality Response Of Pima Cotton To Nitrogen And Phosphorus Deficiency, Haile Tewolde, C. J. Fernandez

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

Imposing a moderate level of nutrient deficiency may be an effective management strategy to limit vegetative growth and enhance maturity of Pima cotton (Gossypium barbadense L.). Whether such deficiency affects fiber quality of American Pima cotton, however, is not well known. A field study was conducted in 1991 and 1992 to determine the fiber quality responses of Pima cotton to nitrogen and phosphorus fertilization ranging between deficient and excess. Pima cotton cv. ‘‘S-7’’ was treated with nitrogen rates ranging between 0 and 269 kg ha-1 in a factorial combination with phosphorus rates ranging between 0 and 44 kg …


Normal Acquisition And Loss Of Bone Mass, Steven A. Abrams Jan 2003

Normal Acquisition And Loss Of Bone Mass, Steven A. Abrams

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

The natural patterns of bone mass accumulation and loss with age represent the templates of individual life cycle periods that are distinguished by marked, physiologically and genetically identifiable, changes in bone mass. During the third trimester of pregnancy, maternal calcium absorption increases and the fetus accumulates about two-thirds of the total bone mass of the term infant. In early infancy, human milk calcium is derived primarily from maternal bone stores, which incur substantial bone losses that are quickly replenished during and after weaning. At puberty, a marked increase in bone mass occurs in conjunction with the initial physical and hormonal …


Potential Relationships Between Physical Traits And Male Broiler Breeder Fertility, S. Mcgary, I. Estevez, M. R. Bakst Jan 2003

Potential Relationships Between Physical Traits And Male Broiler Breeder Fertility, S. Mcgary, I. Estevez, M. R. Bakst

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

Genetic selection in primary broiler breeders may modify skeletal structure, possibly impeding semen transfer, and could alter the size and degree of fluctuating asymmetry (FA) of bilateral traits associated with fertility. Hence, we hypothesized specific morphometric traits could predict differential fertility. Sixty primary broiler breeder males from Strains A and B (n = 30/strain) were individually housed with an average of 10 females per male. Male fertility and sperm penetration (SP) through the perivitelline layer were estimated on fresh eggs. At 50 wk, BW, keel length (KL), posterior pelvic width and length (PPW, PPL), dorsal pelvic width and length (DPW, …


Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba Jan 2003

Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba

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

Little information regarding the effectiveness of UV radiation on the inactivation of caliciviruses and enteric adenoviruses is available. Analysis of human calicivirus resistance to disinfectants is hampered by the lack of animal or cell culture methods that can determine the viruses’ infectivity. The inactivation kinetics of enteric adenovirus type 40 (AD40), coliphage MS-2, and feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, were determined after exposure to low-pressure UV radiation in buffered demand-free (BDF) water at room temperature. In addition, UV disinfection experiments were also carried out in treated groundwater with …


Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines Jan 2003

Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines

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

Soft wheat (Triticum aestivum L.) quality tests (milling and baking quality) and starch characteristics (amylose concentration, X-ray diffractograms, thermal properties and pasting properties) were determined for eight granule-bound starch synthase (GBSS: waxy protein) genotypes in a soft wheat background. Lines carrying two null alleles showed reduced amylose concentrations relative to those of single null and wild-type lines. Milling and baking quality traits were clearly different between waxy (triple null) and the other genotypes. Waxy lines showed the highest alkaline water retention (AWRC) capacity; even though, the protein concentration was not significantly different from some double null and single null …


Watershed Vulnerability To Herbicide Transport In Northern Missouri And Southern Iowa Streams, R. N. Lerch, P. E. Blanchard Jan 2003

Watershed Vulnerability To Herbicide Transport In Northern Missouri And Southern Iowa Streams, R. N. Lerch, P. E. Blanchard

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

Herbicide contamination of streams has been well documented, but little is currently known about the specific factors affecting watershed vulnerability to herbicide transport. The primary objectives of this study were (1) to document herbicide occurrence and transport from watersheds in the northern Missouri/ southern Iowa region; (2) to quantify watershed vulnerability to herbicide transport and relate vulnerability to soil properties; and (3) to compute the contribution of this region to the herbicide load of the Missouri and Mississippi Rivers. Grab samples were collected under baseflow and runoff conditions at 21 hydrologic monitoring stations between April 15 and July 15 from …


Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson Jan 2003

Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson

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

Four species of saltcedars, Tamarix ramosissima Ledeb., Tamarix chinensis Lour., Tamarix parviflora DC., and T. canariensis Willd. and their hybrids, are exotic, invasive small trees from Asia that cause great damage to riparian ecosystems of the western United States. They displace native plant communities, degrade wildlife habitat (including that of many endangered species), increase soil salinity and wildfires, lower water tables, reduce water available for agriculture and municipalities, and reduce recreational use of affected areas. Phytophagous insects are abundant on saltcedar in the Old World and we selected Diorhabda elongata Brullé deserticola Chen as the top candidate biological control agent …


Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins Jan 2003

Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins

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

Adults and larvae of Diorhabda elongata Brullé subspecies deserticola Chen feed on the foliage of saltcedars (Tamarix spp.). All three instars are black, the 2nd with an indistinct, and the 3rd with a distinct yellowish lateral stripe; full-grown larvae reach ca. 9mm in length and pupate in cells in litter on the ground or a few cm below the soil surface. Adults are yellowish with two dark brown stripes on each elytron. Duration of the egg averaged 5 days, 1st instar 4.9 days, 2nd instar 4.8 days, 3rd instar 7.4 days, prepupa 4.8 days, and pupa 7.1 days at …


Differential Amplification Of Sequence Heterogeneous Ribosomal Rna Genes And Classification Of The ‘Fragaria Multicipita’ Phytoplasma, Robert E. Davis, Rasa Jomantiene, Audrone Kalvelyte, Ellen L. Dally Jan 2003

Differential Amplification Of Sequence Heterogeneous Ribosomal Rna Genes And Classification Of The ‘Fragaria Multicipita’ Phytoplasma, Robert E. Davis, Rasa Jomantiene, Audrone Kalvelyte, Ellen L. Dally

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

Ribosomal (r) RNA interoperon sequence heterogeneity in the ‘Fragaria multicipita’ phytoplasma, a member of group 16SrVI, was initially observed in RFLP patterns of rDNA amplified in the polymerase chain reaction (PCR), and was confirmed through sequence analysis of cloned rDNA. Sequences from operons rrnA and rrnB were amplified in PCR primed by primer pair P1/P7 but from only rrnA in PCR primed by primer pair R16mF2/R16mR1. Preferential amplification of DNAfrom operon rrnA was explained by base mismatches between the R16mF2/R16mR1 primers and primer annealing sites in rrnB. The results revealed potential for classification of a phytoplasma into two …


Description And Analysis Of Two Internet-Based Databases Of Insect Pathogens: Edwip And Vidil, S. M. Braxton, D. W. Onstad, D. E. Docktor, R. Giordano, R. Larsson, R. A. Humber Jan 2003

Description And Analysis Of Two Internet-Based Databases Of Insect Pathogens: Edwip And Vidil, S. M. Braxton, D. W. Onstad, D. E. Docktor, R. Giordano, R. Larsson, R. A. Humber

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

In 1996, two searchable databases covering insect pathogens were posted on the World Wide Web: the Ecological Database of the World's Insect Pathogens (EDWIP) and the Viral Diseases of Insects in the Literature database (VIDIL). In this paper, we describe the format and contents of EDWIP and VIDIL on the World Wide Web. EDWIP contains over 9400 pathogen–host association records, 677 negative test result or ‘‘no association’’ records, 4454 host species, 2285 pathogen species records, and 2057 bibliographical references. Species of Coleoptera and Lepidoptera are the best represented groups in EDWIP. Lepidopteran species account for the most associations of any …


Enhanced Bioremediation Of Soil Containing 2,4-Dinitrotoluene By A Genetically Modified Sinorhizobium Meliloti, Sisir K. Dutta, Gail P. Hollowell, Fawzy M. Hashem, L. David Kuykendall Jan 2003

Enhanced Bioremediation Of Soil Containing 2,4-Dinitrotoluene By A Genetically Modified Sinorhizobium Meliloti, Sisir K. Dutta, Gail P. Hollowell, Fawzy M. Hashem, L. David Kuykendall

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

The symbiotic nitrogen-fixing soil bacterium, Sinorhizobium meliloti, is well known for its ability to interact with the leguminous plant Medicago sativa L. It has, however, not been reported that this species possesses the capability to degrade toxic nitroaromatic compounds, such as 2,4-dinitrotoluene (DNT) which is commonly associated with the degradation of the explosive trinitrotoluene (TNT). In this study, the pJS1 DNT-biodegradative plasmid was genetically transferred to S. meliloti strain USDA 1936, which was confirmed by plasmid profile analysis. Several standard analytical and chemical tests including high performance liquid chromatography (HPLC), nitrite (NO2) release assays, rhizosphere population and plant greenhouse …


Hepatitis Associated With A Sarcocystis Canis–Like Protozoan In A Hawaiian Monk Seal (Monachus Schauinslandi), D. Yantis, R. Moeller, R. Braun, C. H. Gardiner, A. Aguirre, J. P. Dubey Jan 2003

Hepatitis Associated With A Sarcocystis Canis–Like Protozoan In A Hawaiian Monk Seal (Monachus Schauinslandi), D. Yantis, R. Moeller, R. Braun, C. H. Gardiner, A. Aguirre, J. P. Dubey

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

A Hawaiian monk seal (Monachus schauinslandi) died in captivity at the National Marine Fisheries Service, Kewalo Basin Facility in Honolulu, Hawaii. The animal was icteric, and the liver was friable. Microscopic lesions were detected in the colon and liver. Colonic lesions included multifocal, necrohemorrhagic colitis associated with gram-negative bacilli. The liver lesions included random hepatic necrosis and cholestasis. Asexual stages of a Sarcocystis canis–like apicomplexan were detected in hepatocytes. The parasite divided by endopolygeny. Merozoites occasionally formed rosettes around a central residual body. Ultrastructurally, merozoites lacked rhoptries. This is the first report of S. canis infection in …


Do Species Evenness And Plant Density Influence The Magnitude Of Selection And Complementarity Effects In Annual Plant Species Mixtures?, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner Jan 2003

Do Species Evenness And Plant Density Influence The Magnitude Of Selection And Complementarity Effects In Annual Plant Species Mixtures?, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner

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

Plant species richness influences primary productivity via mechanisms that (1) favour species with particular traits (selection effect) and (2) promote niche differentiation between species (complementarity). Influences of species evenness, plant density and other properties of plant communities on productivity are poorly defined, but may depend on whether selection or complementarity prevails in species mixtures. We predicted that selection effects are insensitive to species evenness but increase with plant density, and that the converse is true for complementarity. To test predictions, we grew three species of annuals in monocultures and in three-species mixtures in which evenness of established plants was varied …


Future Directions For The Integrated Csfii-Nhanes: What We Eat In America–Nhanes, Johanna Dwyer, Mary Frances Picciano, Daniel J. Raiten Jan 2003

Future Directions For The Integrated Csfii-Nhanes: What We Eat In America–Nhanes, Johanna Dwyer, Mary Frances Picciano, Daniel J. Raiten

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

The history of the integration of the dietary data collection from the National Health and Nutrition Examination Survey (NHANES) and the Continuing Survey of Food Intakes by Individuals (CSFII) is reviewed. The purposes and process of the workshop are presented. The three key topics of the workshop are summarized. The key roles of cosponsors and participants are acknowledged.


United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette Jan 2003

United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette

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

An overview of ARS research in the field of veterinary pests is presented. Results of research from the past three years on ticks, fire ants, nuisance flies, mosquitoes, sand flies and black flies, among others, are included. Where applicable, significance of research is discussed.


Exploratory Surveys In Australia And Asia For Natural Enemies Of Old World Climbing Fern, Lygodium Microphyllum: Lygodiaceae, John A. Goolsby, Anthony D. Wright, Robert W. Pemberton Jan 2003

Exploratory Surveys In Australia And Asia For Natural Enemies Of Old World Climbing Fern, Lygodium Microphyllum: Lygodiaceae, John A. Goolsby, Anthony D. Wright, Robert W. Pemberton

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

Lygodium microphyllum, Old World climbing fern, is native to the wet tropics and subtropics of the Old World and an invasive weed in southern Florida. Exploration for natural enemies of this weed was conducted between 1997 and 2002 in Australia, China, India, Indonesia, Japan, Malaysia, New Caledonia, Singapore, Taiwan, Thailand, and Vietnam. Two species of mites and 20 insect species were collected. The eriophyid mite, Floracarus perrepae Knihinicki and Boczek, was the most widely distributed and appeared to cause significant damage to the plant over time. Several unique geographical genotypes of F. perrepae were identified. Other promising candidates for …