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Chlorophyll, Chloroplast Ribosomal Rna, And Dna Are Reduced By Rarley Stripe Mosaic Virus Systemic Infection, Myron K. Brakke, J. L. White, R. G. Samson, Jay Joshi

Department of Plant Pathology: Faculty Publications

Barley stripe mosaic virus became systemic 3 days alter inoculation of barley plants in the two-leaf stage. The first leaf to show mosaic was leaf 3. which was 4.5 cm long at 3 days after inoculation when it was invaded by virus. Since all of Ieaf 3 showed mosaic, the events leading to mosaic occurred during cell expansion and after cell division. which is limited to the basal centimeter of young cereal leaves. Molecular changes associated with mosaic formation included a 509, reduction in chloroplast ribosomal RNA and chlorophyll, expressed as amount per unit DNA, in young leaves with an …

Comparisons Of Mitochondrial Dna From The Sibling Species Heterodera Glycines And H. Schachtii, A. D. Radice, Thomas O. Powers, Laurie J. Sandall, R. D. Riggs

Department of Plant Pathology: Faculty Publications

Restriction fragment patterns of mitochondrial DNA from sibling species of cyst nematodes Heterodera glycines and H. schachtii were examined. Fourteen restriction endonucleases recognizing four, five, and six base-pair sequences yielded a total of 90 scorable fragments of which 10% were shared by both species. Mitochondrial genome sizes for H. glycines and H. schachtii were estimated to be 22.5-23.5 kb and 23.0 kb, respectively. A single wild type mitochondrial genome was identified in all populations of H. glycines examined, although other mitochondrial genomes were present in some populations. The H. schachtii genome exhibited 57 scorable fragments, compared with 33 identified in …

Estimation Of Genetic Divergence In Meloidogyne Mitochondrial Dna, Thomas O. Powers, Laurie J. Sandall

Department of Plant Pathology: Faculty Publications

Restriction fragments from purified mitochondrial DNA can be readily detected following rapid end-labeling with [α-³²P] nucleoside triphosphates and separation by gel electropboresis. Mitochondrial DNA from 12 populations of Meloidogyne species was digested with 12 restriction enzymes producing more than 60 restriction fragments for each species. The mitochondrial genome of M. arenaria is the most genetically distinct of the four species compared. M. arenaria shows approximately 2.1-3.1% nucleotide sequence divergence from the mitochondrial genomes of M. javanica, M. incognita, and M. hapla. Among the latter three species, interspecific estimates of sequence divergence range from 0.7 to …

Male Sterility In Soybean-An Overview, Robert Graybosch, Reid G. Palmer

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

The most common type of reproductive mutations observed in the soybean [Glycine max (L.) Merr.]are those that induce male sterility.The high frequency of occurrence of male-sterile mutations indicates that a number of genes influence the processes of microgametogenesis and microsporogenesis. The current knowledge of these mutations is summarized. The origins of male-sterile mutations, their inheritance patterns, and known linkage relationships are detailed. The phenotypic expression of male-sterile mutations, including their effects on both male and female reproduction, is discussed. The influence of environment on the expressivity of male sterile mutations, and the effects of male-sterile mutations on physiological processes …

Nebraska Summary: S031 Massey Ferguson 375, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Taxonomy, Systematics, And Ecology Of Helminth Parasites Of The Ringed Seal, Phoca Hispida Schreber, In Alaskan Waters, Ann Marie Adams

Harold W. Manter Laboratory of Parasitology: Library Materials

The genus Orthosplaochnus Odhner, 1905 (Trematoda: Campulidae) was revised, with eight species recognized. Odhneriella Skriabin, 1915 was placed in synonymy with Orthosplanchnus, and Hadwenius was shown to be valid. Orthosplanchnus rossicus (Skriabin, 1915) (syn. Odhneriella rossica) was redescribed.

Inconsistencies in the diagnosis of the Anophryocephalus Baylis, 1922 (Cestoda: Tetrabothriidae) were discussed, along with the basis for generis revision. The taxonomic histories of certain genera of nematodes (e.g., Contracaecum Railliet and Henry, 1912; Dipetalonema Diesing; 1861; and Pseudoterranova Mosgovoi, 1950) were given to explain their present status.

The helminth-fauna of the ringed seal in the North Pacific was compared …

Empowering A Feminist Ethic For Social Science Research: Nebraska Sociological Feminist Collective, Beth Hartung, Jane C. Ollenburger, Helen A. Moore, Mary Jo Deegan

Department of Sociology: Faculty Publications

An ethic defines the general nature of the morals. rules and standards governing the conduct and choices of individuals as well as members of a profession (Oxford English Dictionary 1971). A feminist ethic for social science research specifically orders these general issues to recognize and account for wimmin's continued oppression within a patriarchal social system and academic disciplines. A feminist ethic identifies this continued oppression as a major contradiction of our research. work and social structure. Within social sciences generally, and sociology specifically. little attention is paid to the underlying patriarchal ethic which informs theory, method and substantive issues. …

Improved Selective Medium For The Isolation Of Treponema Hyodysenteriae, Robert A. Kunkle, J. M. Kinyon

School of Veterinary and Biomedical Sciences: Faculty Publications

An agar medium with improved selection for Treponema hyodysenteriae was developed. Cultures of T. hyodysenteriae and T. innocens, feces from 11 clinically normal pigs, and colonic contents from 6 pigs with gross lesions consistent with swine dysentery were diluted in phosphate-buffered saline and plated on Trypticase soy agar (BBL Microbiology Systems, Cockeysville, Md.) with 5% citrated bovine blood (TSA), TSA with 400 ,ug of spectinomycin per ml (TSA-S400), TSA-S400 with 25 ,ug each of colistin and vancomycin per ml, and TSA with 5% pig feces extract and five antimicrobial agents (spiramycin, rifampin, vancomycin, colistin, and spectinomycin) (BJ). Viable numbers …

1988 Nebraska Swine Report

Nebraska Swine Reports

1988 Nebraska Swine Report

Nebraska Summary: S048 John Deere 2155, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Technological Change And Child Behavior Among The !Kung, Patricia Draper, Elizabeth Cashdan

Department of Anthropology: Faculty Publications

How does change in one part of a social system affect other parts? This is the central question that must be answered in order to understand the process through which culture changes. This paper is about a small piece of the problem. It investigates how changes in subsistence economy affect child behavior and the relations between parents and children among !Kung Bushmen of Western Botswana. We will show that the adoption of a sedentary life style and a new technology of food production is associated with changes in the social interactions between parents and children and between children and their …

Framing ‘Bomb Talk’: The Macro Consequences Of The Microfoundations Of Social Interaction In A Goffmanian Nuclear World, Michael R. Hill

Department of Sociology: Faculty Publications

This paper, originating with issues generated in Professor Deegan’s seminar on contemporary sociological theory at the University of Nebraska, explores the “frames” or microfoundations of everyday interaction and their consequences for the ultimate macrosociological threat: global nuclear annihilation. The theoretical basis of this study is Erving Goffman’s Frame Analysis: An Essay on the Organization of Experience. The adequacy and comprehensiveness of Goffman’s major constructs are substantiated by data from the everyday world of newspapers and popular culture. “Keys” (or transformational conventions) are pivotal in this analysis. The central thesis of this paper holds that the keys used to transformationally …

Nucleotide Sequence Of The Fadr Gene, A Multifunctional Regulator Of Fatty Acid Metabolism In Escherichia Coli, Concetta C. Dirusso

Department of Biochemistry: Faculty Publications

The Escherichia coli fadR gene is a multifunctional regulator of fatty acid

and acetate metabolism. In the present work the nucleotide sequence of the

1.3 kb DNA fragment which encodes FadR has been determined. The coding

sequence of the fadR gene is 714 nucleotides long and is preceded by a typical

E. coli ribosome binding site and is followed by a sequence predicted to be

sufficient for factor-independent chain termination. Primer extension experiments

demonstrated that the transcription of the fadR gene initiates with an

adenine nucleotide 33 nucleotides upstream from the predicted start of

translation. The derived fadR peptide has …

Variation In Chromosome Length Among Five Biotypes Of The Greenbug (Homoptera: Aphididae), Z. B. Mayo, K. J. Starks, D. J. Banks, R. A. Veal

Department of Entomology: Faculty Publications

Chromosome-length measurements from five greenbug, Schizaphis graminum (Rondani), biotypes (B, C, E, F, and Maryland) were compared by discriminant analyses procedures. There were highly significant (P = 0.0001) differences in total lengths of chromosome sets among biotypes. In individual paired comparisons, where each biotype was compared with only one other biotype at a time, chromosome measurements correctly classified aphids to their respective biotype in 45-85% of the cases. Degree of correct classification was dependent on the two biotypes being compared and the discriminant function used in the analysis. Results indicate that there are two groups of biotypes that can be …

Variable Resistance To Homopterans In Rice Cultivars, E. A. Heinrichs

Department of Entomology: Faculty Publications

Rice-breeding programs in Asia have successfully provided farmers with cultivars that have genetic resistance to the major insect pests, including the leafhoppers and planthoppers. The widespread planting of resistant cultivars has resulted in the selection of hopper populations that have overcome the resistance factor(s) in the plant. Procedures to measure the degree and rate of selection for virulence on resistant cultivars have been developed, and rice-breeding strategies to increase the stability of hopper-resistant cultivars have been implemented.

Resistant cultivars have been widely and successfully used in Asia and Central and South America in the management of certain rice homopterans. Rice-breeding …

A Seed Midge Pest Of Big Bluestem, M. R. Carter, G. R. Manglitz, M. D. Rethwisch, Kenneth P. Vogel

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

A Cecidomyiid midge reared from the panicles of big bluestem (Andropogon gerardii Vitman (var. gerardii) at Mead, Neb., was identified as Contrarinia wattsi Gagne. This midge was previously known only from panicles of little bluestem (Schizachyrium scoparium (Michx.) Nash) in New Mexico. In Nebraska, C. wattsi appears to have a minimum of 3 generations per season. Larvae of the earlier generations leave the florets after completing development, making it difficult to associate floret damage with the midge. Larvae of the last generation of a season remain in diapause, in the floret, throughout the winter. Evidence obtained …

Comparison Of Two Gelling Agents For Screwworm (Diptera: Calliphoridae) Larval Diets, David B. Taylor

Department of Entomology: Faculty Publications

A sodium polyacrylamide polyacrylate gelling agent, Water-Lock G-400, and a galactan polysaccharide agent, carrageenan, were compared for solidifying larval diets of the screwworm, Cochliomyia hominivorax (Coquerel). Water-Lock diet produced larger pupae with less larval mortality than did carrageenan diet. Pupae from larvae reared on the Water-Lock diet exhibited higher emergence and produced adults with higher fecundity. Water-Lock diet also produced larger larvae at 56 h after oviposition. Densities in excess of 300 mg of eggs (16,200 eggs) per liter of Water-Lock gelled diet did not increase larval yield but did reduce larval weight and survival.

Oligocene Calcareous-Nannofossil Biostratigraphy From Leg 101, Site 628, Little Bahama Bank Slope, Michael J. Moran, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

Drilling at Hole 628A, Leg 101 of the Ocean Drilling Program, recovered a thick, relatively complete Oligocene section of nannofossil-foraminifer chalk and ooze. Sediments from Cores 101-628A-16H through 101-628A-29X were examined using the light microscope to provide information about biostratigraphy of calcareous nannofossils. Several authors noted a problem in distinguishing the first appearance of species within the Sphenolithus predistentus-S. ciperoensis lineage of the mid-Oligocene, particularly Sphenolithus ciperoensis, because of the gradual evolution of its members. Successful separation of species in this lineage is critical for accurately dating relative age of mid- and upper-Oligocene nannofossil sediments. Length and taper of …

Size Differences In Migrant Sandpiper Flocks: Ghosts In Ephemeral Guilds, Jan L. Eldridge, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Scolopacid sandpipers were studied from 1980 until 1984 during spring migration in North Dakota. Common species foraging together in mixed-species flocks differed in bill length most often by 20 to 30 percent (ratios from 1.2:1 to 1.3:1). Observed flocks were compared to computer generated flocks drawn from three source pools of Arctic-nesting sandpipers. The source pools included 51 migrant species from a global pool, 33 migrant species from a Western Hemisphere pool, and 13 species that migrated though North Dakota. The observed flocks formed randomly from the available species that used the North Dakota migration corridor but the North Dakota …

Determinants Of Breeding Distribution Of Ducks, Douglas H. Johnson, James W. Grier

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The settling of breeding habitat by migratory waterfowl is a topic of both theoretical and practical interest. We use the results of surveys conducted annually during 1955-81 in major breeding areas to examine the factors that affect the distributions of 10 common North American duck species. Three patterns of settling are described: homing, opportunistic, and flexible. Homing is generally more pronounced among species that use more stable (more predictable) wetlands, such as the redhead (Aythya americana), canvasback (A. valisineria), lesser scaup (A. affinis), mallard (Anas platyrhynchos), gadwall (Anas strepera), and …

Wolf Distribution And Road Density In Minnesota, L. David Mech, Steven H. Fritts, Glenn L. Radde, William J. Paul

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Distribution of the wolf (Canis lupus) in parts of Wisconsin (Thiel 1985) and Michigan and Ontario (Jensen et al. 1986) has been related to the density of roads passable by 2-wheel-drive vehicles. Wolves in those regions generally do not occur where road densities exceed 0.58 km/km², whereas similar areas nearby with fewer roads do contain wolves.

In a small segment of the wolf range in Minnesota, wolves did not have territories where roads exceeded a density of 0.73 km/km² (T. K. Fuller, Minnesota Department of Natural Resources, unpublished data). In another small area of Minnesota …

Cuticular Hydrocarbons As Chemotaxonomic Characters For Nasutitermes Corniger (Motschulsky) And N. Ephratae (Holmgren) (Isoptera: Termitidae), Ralph W. Howard, Barbara L. Thorne, Sally C. Levings, C. A. Mcdaniel

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Forty-four cuticular hydrocarbon components from workers of the termites Nasutitermes corniger (Motschulsky) and N. ephratae (Holmgren) from three localities in Panama were characterized by capillary gas chromatography-electron impact mass spectrometry. Both species contain qualitatively identical homologous series of n-alkanes; 2-, 3-, 11-,13-,14-, and 15-methylalkanes; 11,15-, 12,16-, and 13,17-dimethylalkanes; and 11,15,19- and 13, 17,21-trimethylalkanes. Both species also contain a single alkene, 9-hentriacontene. The two species, however, are readily distinguished chemically by differences among the relative abundances of 11 of their major hydrocarbon components.

Purification Of Maturation-Promoting Factor, An Intracellular Regulator Of Early Mitotic Events, Manfred J. Lohka, Marianne K. Hayes, James L. Maller

School of Veterinary and Biomedical Sciences: Faculty Publications

Maturation-promoting factor causes germinal vesicle breakdown when injected into Xenopus oocytes and can induce metaphase in a cell-free system. The cell-free assay was used to monitor maturation-promoting factor during its purification from unfertilized Xenopus eggs. Ammonium sulfate precipitation and six chromatographic procedures resulted in a preparation purified >3000-fold that could induce germinal vesicle breakdown within 2 hr when injected into cycloheximide- treated oocytes. Proteins of 45 kDa and 32 kDa were correlated with fractions of highest activity in both assays. These fractions contained a protein kinase activity able to phosphorylate the endogenous 45-kDa protein, as well as histone Hi, phosphatase …

Considerations In Breeding Endophyte-Free Tall Fescue Forage Cultivars, Jeffrey F. Pedersen, D. A. Sleper

Department of Agronomy and Horticulture: Faculty Publications

Breeding tall fescue (Festuca arundinacea Schreb.) cultivars that are free of the endophytic fungus Acremonium coenophialum Morgan-Jones and Gams [previously identified and referred to as Epichloe typhina (Fries) Tulasne] is necessary to improve animal performance. The techniques used in developing new cultivars are not greatly different from those used previously, with one exception. Prior to the evaluation of new tall fescue lines or populations, the endophyte needs to be eliminated from the seed or the plants. Several techniques utilizing aging, heat, or chemical treatment are being used to effectively accomplish this in the seed. Methods for permanently eliminating the endophyte …

Levels And Timing Of Nitrogen Fertilizer Applications For Tall Fescue In Central Alabama, J. W. Odom, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Tall fescue (Festuca arundinacea Schreb.), the most important cool season perennial pasture grass in the United States, is generally well adapted to the northern two-thirds of Alabama. Unfortunately, the most commonly grown tall fescue cultivar, Kentucky 31, is of northern origin and is dormant during the winter. To reduce this problem, AU Triumph was selected from Mediterranean germplasm. The Alabama Agricultural Experiment Station released this cultivar to growers in 1981. Compared to Kentucky 31, AU Triumph produces about 80 percent more forage during the winter and produces mature seed about 2 weeks earlier in the spring. Total annual forage production …

Monitoring Natural Air Corn Drying—A Demonstration Project, Richard O. Pierce, Gary L. Zoubek

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A demonstration project is described where natural air corn drying performance was monitored weekly and drying results were printed in a local newspaper. The newspaper articles also gave management recommendations for the upcoming week. Similar demonstration projects can be conducted using the procedures described in this paper.

Correlation Of Starch Recovery With Assorted Quality Factors Of Four Corn Hybrids, Curtis L. Weller, Marvin R. Paulsen, Marvin P. Steinberg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A laboratory wet-milling process was developed for use in determining starch recovery of yellow dent corn. The effects of harvest moisture and drying air temperature on starch recovery were investigated for four hybrids. A split split-plot experimental design was used to evaluate the effects. Starch recovery was not significantly different among the hybrids; however, it did decreases both harvest moisture and drying air temperature increased. Starch recovery was correlated with quantitative measures of assorted quality factors. Regression analysis found starch recovery to be a function of starch content, test weight, and ethanol-soluble protein.

Calibration Accuracy Of Pesticide Application Equipment, Robert Grisso, E. J. Hewett, Elbert C. Dickey, R. D. Schnieder, E. W. Nelson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Afield survey of 140 private and commercial pesticide applicators was conducted during the spring of 1986 in 12 counties of central and eastern Nebraska. The results showed that one out of every three cooperators was applying pesticides within ± 5% of their intended application rate. Results indicated that applicators have reduced application errors from that of a similar survey conducted in 1979. However, most errors still can be traced to incorrect calibration. Ninety-four percent of the cooperators used some type of calibration method. Two-thirds used the "Known Area" method. Those using a calibration method more than once a year had …

Surface Cover From Corn Residue On Sandy Soils, R. Todd, Norman L. Klocke, Elbert C. Dickey, Dennis Bauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Corn residue left as surface cover after land preparation and planting by various combinations of tillage implements and surface planters, respectively, was measured on four research/ demonstration sites with sandy soils in Nebraska. Surface cover ranged from 51 to 80% for the no-till treatments to 14 to 53% for the twice-disked treatments. The wide range in cover was due to the amount of antecedent residues from the previous crop and the soil type which ranged from sandy loam to tine sands. Other tillage implements included a rolling cultivator, sweep-plow, and mulch-treader.

Reduced Co2/O2 Specificity Of Ribulose-Bisphosphate Carboxylase/Oxygenase In A Temperature-Sensitive Chloroplast Mutant Of Chlamydomonas, Zhixiang Chen, Chris J. Chastain, Souhail R. Al-Abed, Raymond Chollet, Robert J. Spreitzer

Department of Biochemistry: Faculty Publications

The Chlamydomonas reinhardtii chloroplast mutant 68-4PP is phenotypically indistinguishable from wild type at 25°C but fails to grow photosynthetically at 35°C. It had about 30% of the wild-type level of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) holoenzyme and carboxylase activity when grown at 25°C, but less than 15% when grown at 35°C. Pulse-labeling with ³⁵S showed that the decrease in enzyme level at the restrictive temperature was not a result of reduced synthesis of enzyme subunits. The CO₂/O₂ specificity factor (V_cK_o/V_oK_c, where V_c and V_o are V_{max …}