Digital Commons Network^™

Effect Of Control Plot Density, Control Plot Arrangement, And Assumption Of Random Or Fixed Effects On Nonreplicated Experiments For Germplasm Screening Using Spatial Models, Boi Sebolai, Jeffrey F. Pedersen, D. B. Marx, D. L. Boykin

Department of Agronomy and Horticulture: Faculty Publications

Early generation selection experiments typically involve several hundred to thousands of lines. Various systematic and statistical techniques have been developed to increase effectiveness and efficiencies in such experiments, including the development and application of spatial statistical models. In this study, mixed model equations were used to provide least squares means (LSMEANs) and best linear unbiased predictors (BLUPs) and compare selection effectiveness and efficiencies to observed (Y) and true values in simulated experiments varying in size (10 X 10, 20 X 20 and 30 X 30 grids), control plots densities (0, 5, 10, 20, and 50%), control plot arrangements (high, medium, …

Review Of The Black Flies (Simuliidae) Of North America By: Peter H Adler, Douglas C Currie, And D Monty Wood, Jerome Hogsette

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

Based on its title, one could expect this volume to be mainly a taxonomic reference for the North American Black Flies, but it is actually much more. The book is organized into five parts, each containing two to three of the 10 total chapters. Part I presents a very comprehensive overview of the subject (Chapter 1), followed by a history of the research (Chapter 2) that contains good historical references, as well as citations that are quite recent. Historical references are always welcome in any review section because they may have been published in regional or local literature that are …

Predicting Plant Extinction Based On Species-Area Curves In Prairie Fragments With High Beta Richness, Brian J. Wilsey, Leanne M. Martin, H. Wayne Polley

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

Species-area relationships and island biogeography theory are commonly used to predict how species richness will decline with fragmentation. There are a variety of largely untested assumptions in these approaches, including the assumptions that populations are distributed uniformly before fragmentation, and that local extinctions are due to effects of small population sizes. If populations are not distributed uniformly, then populations can be abundant locally but rare globally. This would cause extinction rates to be smaller than predicted.We tested extinction theory by developing estimates of the number of plant species that should be present in small tallgrass prairie fragments and then testing …

Patterns Of Plant Species Diversity In Remnant And Restored Tallgrass Prairies, H. Wayne Polley, Justin D. Derner, Brian J. Wilsey

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

To restore diversity of native vegetation, we must understand factors responsible for diversity in targeted communities. These factors operate at different spatial scales and may affect the number and relative abundances of species differently. We measured diversity of plant species and functional groups of species in replicated plots within paired restored and remnant (relic) tallgrass prairies at three locations in central Texas, U.S.A.

A Modified Molybdenum Blue Method For Orthophosphate Determination Suitable For Investigating Enzymatic Hydrolysis Of Organic Phosphates, Zhongqi He, C. Wayne Honeycutt

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

In characterizing organic phosphorus (P_o) by phosphatase hydrolysis, the quantity of hydrolyzable P_o is represented by the difference in orthophosphate [i.e., inorganic P (P_i)] determined after and prior to enzymatic incubation. Therefore, precise determination of P_i is of major importance for accurate application of the enzymatic hydrolysis approach. The strong acid conditions required for conventional molybdenum blue methods interferes with P_i determination due to rapid hydrolysis of labile P_o and precipitation of enzymes (proteins). The molybdenum blue method of Dick and Tabatabai in 1977 reduced errors pertaining to nonenzymatic hydrolysis of P …

Comparison Of Protein Solubilization Methods Suitable For Proteomic Analysis Of Soybean Seed Proteins, Savithiry Natarajan, Chenping Xu, Thomas J. Caperna, Wesley M. Garrett

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

Extraction of soybean seed proteins for two-dimensional polyacrylamide gel electrophoresis (2D–PAGE) and mass spectrometry analysis is challenging and inconsistent. In this study, we compared four different protein extraction/solubilization methods—urea, thiourea/urea, phenol, and a modified trichloroacetic acid (TCA)/acetone—to determine their efficacy in separating soybean seed proteins by 2D–PAGE. In all four methods, seed storage proteins were well separated by 2D–PAGE with minor variations in the intensity of the spots. The thiourea/urea and TCA methods showed higher protein resolution and spot intensity of all proteins compared with the other two methods. In addition, several less abundant and high molecular weight proteins were …

Size-Dependent Feeding And Reproduction By Boll Weevil (Coleoptera: Curculionidae), S. M. Greenberg, D. W. Spurgeon, Thomas W. Sappington, M. Sétamou

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

The considerable variation in adult size of the boll weevil, Anthonomus grandis grandis Boheman, has been well documented, but the influences of adult size on reproductive rate are not known. We examined the relationship between the size of boll weevils and their feeding and oviposition. Weevils weighed to the nearest milligram were grouped into five categories based on pupal weight:≤5, 6-10, 11-15, 16-20, and>20 mg. Numbers of lifetime punctures produced in flower buds (squares) of cotton, Gossypium hirsutum L., by both sexes of adults tended to increase with pupal weight. Boll weevil females with pupal weights >10 mg produced …

Comparison Of Contact And Spatial Repellency Of Catnip Oil And N,N-Diethyl-3-Methylbenzamide (Deet) Against Mosquitoes, Ulrich R. Bernier, Kay D. Furman, Daniel L. Kline, Sandra A. Allan, Donald R. Barnard

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

Nepetalactone, the primary component of catnip oil, was compared with the repellent N,N-diethyl-3-methylbenzamide (deet) for its ability to affect the host-seeking ability of Aedes aegypti (L.). A triple cage olfactometer was used to bioassay each substance and to assess its attraction inhibition (spatial repellent) attributes when combined with the following attractants: carbon dioxide, acetone, a blend of L-lactic acid and acetone, and human odors. Repellent tests were conducted with each substance against female Ae. aegypti, Anopheles albimanus Weidemann, and Anopheles quadrimaculatus Say. Catnip oil and deet were both weakly attractive to Ae. aegypti, catnip oil was the better spatial …

Habitat Corridors Function As Both Drift Fences And Movement Conduits For Dispersing Flies, Joanna H. Fried, Douglas J. Levey, Jerome Hogsette

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

Corridors connect otherwise isolated habitat patches and can direct movement of animals among such patches. In eight experimental landscapes, we tested two hypotheses of how corridors might affect dispersal behavior. The Traditional Corridor hypothesis posits that animals preferentially leave patches via corridors, following them into adjacent patches. The Drift Fence hypothesis posits that animals dispersing through matrix habitat are diverted into patches with corridors because they follow corridors when encountered. House flies (Musca domestica L.), a species that prefers the habitat of our patches and corridors, were released in a central patch (100x100 m) and recaptured in peripheral patches …

Post-Release Evaluation Of Biological Control Of Bemisia Tabaci Biotype ‘‘B’’ In The Usa And The Development Of Predictive Tools To Guide Introductions For Other Countries, John A. Goolsby, Paul J. Debarro, Alan A. Kirk, Robert W. Sutherst, Luis Canas, Matthew A. Ciomperlik, Peter C. Ellsworth, Juli R. Gould, Diana M. Hartley, Kim A. Hoelmer, Steven E. Naranjo, Mike Rose, William J. Roltsch, Paul A. Ruiz, Charles H. Pickett, Don C. Vacek

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

Climatic matching and pre-release performance evaluation were useful predictors of parasitoid establishment in a retrospective analysis of a classical biological control program against Bemisia tabaci biotype ‘‘B’’ in the USA. Laboratory evaluation of 19 imported and two indigenous parasitoid species in quarantine on B. tabaci showed that the Old World Eretmocerus spp, had the highest attack rate. The climate matching program CLIMEX was used to analyze the establishment patterns of five Old World Eretmocerus spp. introduced to the Western USA. The top matches ±10% for the climate of the area of introduction and origin of the introduced parasitoids always included …

Protocols For Nationally Coordinated Laboratory And Field Research On Manure Nitrogen Mineralization, C. W. Honeycutt, T. S. Griffin, Brian J. Wienhold, Bahman Eghball, S. L. Albrecht, J. M. Powell, B. L. Woodbury, K. R. Sistani, R. K. Hubbard, H. A. Torbert, R. A. Eigenberg, R. J. Wright, M. D. Jawson

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

The National Program structure of USDA-ARS provides an opportunity to coordinate research on problems of national and global significance. A team of USDA-ARS scientists is conducting nationally coordinated research to develop predictions of manure N availability to protect water quality and improve farm solvency. Experimental design and research protocols were developed and used in common across all participating locations. Laboratory incubations are conducted at each location with a minimum of three soils, three temperatures, two wetting/drying regimes, and two manure treatments. A soil from the central United States (Catlin silt loam, fine-silty, mixed, superactive, mesic Oxyaquic Argiudoll) is used as …

Biocontrol Agents Applied Individually And In Combination For Suppression Of Soilborne Diseases Of Cucumber, Daniel P. Roberts, Scott M. Lohrke, Susan L. F. Meyer, Jeffry S. Buyer, John H. Bowers, C. Jacyn Baker, Wei Li, Jorge T. De Souza, Jack A. Lewis, Soohee Chung

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

The soilborne pathogens Rhizoctonia solani, Pythium ultimum, and Meloidogyne incognita can cause severe economic losses to field- and greenhouse-grown cucumber. A collection of bacterial isolates and isolates GL3 and GL21 of Trichoderma virens were screened for suppression of diseases caused by these pathogens. T. virens isolates GL3 and GL21 provided the most effective suppression of damping-off caused by R. solani in greenhouse bioassays. Burkholderia ambifaria BC-F, B. cepacia BC-1, and Serratia marcescens N1-14 also provided significant suppression of R. solani relative to the pathogen check in some experiments. T. virens isolates GL3 and GL21 and S. marcescens isolates …

Risk And Ethics In Biological Control, Ernest S. Delfosse

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

All introduced natural enemies present a degree of risk to nontarget species. Since most biological control programs use relatively host-specific natural enemies, the risk to nontarget species is generally very low, particularly from biological control of weeds, which uses extensively tested and validated host-specificity testing procedures to predict risk. However, many of the published comments about risks of biological control are superficial or misleading, often inappropriately lumping risk from all taxa of agents as “the risk of biological control,” and ignore the potential benefits, rather than dealing with species-by-species risk and benefits. Particularly confounding accurate predictions is the common mixing …

Summaries Of Arkansas Cotton Research 2003, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

A Single Amino Acid Substitution In Soybean Vspα Increases Its Acid Phosphatase Activity Nearly 20-Fold, Oranuch Leelapon, Gautam Sarath, Paul E. Staswick

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

Soybean [Glycine max (L.) Merr.] contains two proteins called vegetative storage proteins (VSPs) that function as temporary storage reserves, but are also closely related to plant acid phosphatases of the haloacid dehalogenase (HAD) superfamily. This study examined the biochemical basis for the relatively low catalytic activity previously reported for these VSPs. The specific activity of purified recombinant VSPα on GMP was about 40-fold lower than for a related soybean root nodule acid phosphatase (APase), which had a specific activity of 845 U mg^-1 protein. Conversion of Ser¹⁰⁶ to Asp increased VSPα activity about 20-fold. This Asp residue …

Putting Genes Into Genetic Coefficients, P. Stephen Baenziger, Gregory S. Mcmaster, Wallace Wilhelm, Albert Weiss, Cynthia J. Hays

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

Plant parameters are critical inputs in crop simulation models and allow a general set of algorithms to represent features of specific cultivars. A subset of plant parameters is often referred to as ‘‘genetic coefficients’’. However, these genetic coefficients are developed from phenotypic observations, usually have a weak genetic basis, and are at best ‘‘genotypic’’ coefficients because they consider the genotype from a very integrative perspective and likely include some impact of environment on the trait or characteristic described. With increased understanding of crop genomes, we believe models can be improved by incorporating genetic coefficients that accurately describe the action of …

Channel Aggradation By Beaver Dams On A Small Agricultural Stream In Eastern Nebraska, M. C. Mccullough, J. L. Harper, D. E. Eisenhauer, M. G. Dosskey

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

agricultural area of eastern Nebraska. A topographic survey was conducted of a reach of Little Muddy Creek where beaver are known to have been building dams for twelve years. Results indicate that over this time period the thalweg elevation has aggraded an average of 0.65 m by trapping 1730 t of sediment in the pools behind dams. Beaver may provide a feasible solution to channel degradation problems in this region.

Activation Of The Oryza Sativa Non-Symbiotic Haemoglobin-2 Promoter By The Cytokinin-Regulated Transcription Factor, Arr1, Emily Ross, Julie M. Stone, Christian Elowsky, Raul Arredondo-Peter, Robert V. Klucas, Gautam Sarath

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

Using in silico methods, several putative phytohormoneresponsive cis-elements in the Oryza sativa nonsymbiotic haemoglobin (NSHB) 1-4 and Arabidopsis thaliana NSHB1-2 promoters have been identified. An OsNSHB2 promoter::GUS reporter gene fusion shows tissue-specific expression in A. thaliana. GUS expression was observed in roots, the vasculature of young leaves, in flowers, and in the pedicel/stem junction. In transient assays, activity of the OsNSHB2 promoter was significantly up-regulated in the presence of the cytokinin, 6-benzylaminopurine (BA). Deletion analyses indicated that the full-length promoter was required for maximal trans-activation in the presence of cytokinin. Mutation of the single cytokinin-regulated ARR1-binding element abolished promoter …

B. R. Wells Rice Research Studies 2003, R. J. Norman, J.-F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice-producing state in the U.S., representing just over 48% of the total U.S. production and 48.5% of the total acres planted to rice. Rice cultural practices vary across the state and across the U.S. However, due to changing political, environmental, and economic times, the practices are dynamic. This survey was initiated in 2002 to monitor how the changing times reflect the changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas where rice is produced. Questions included topics such as …

Multi-Trophic Level Interactions In A Cassava-Maize Mixed Cropping System In The Humid Tropics Of West Africa, F. Schulthess, A. Chabi-Olaye, S. Gounou

All Peer-Reviewed Publications

Multi-trophic level interactions in a mixed crop, involving cassava and maize, were studied in derived-savanna in Benin, West Africa. Two trials were planted, one during the short rainy season two months before onset of the dry season and one during the long rainy season in spring. Key pests under study on maize were the noctuid Sesamia calamistis Hampson and the pyralids Eldana saccharina Walker and Mussidia nigrivenella Ragonot, and on cassava, the exotic mealybug, Phenacoccus manihoti Matile-Ferrero and its encyrtid parasitoid Apoanagyrus lopezi De Santis. Both crops received insecticide treatments to assess the crop loss by a pest species. On …

K8 And K12 Are Biotinylated In Human Histone H4, Gabriela Camporeale, Elizabeth E. Shubert, Gautam Sarath, Ronald Cerny, Janos Zempleni

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

Folding of DNA into chromatin is mediated by binding to histones such as H4; association of DNA with histones is regulated by covalent histone modifications, e.g. acetylation, methylation, and biotinylation.We sought to identify aminoacid residues that are biotinylated in histone H4,and to determine whether acetylation and methylation of histones affect biotinylation. Synthetic peptides spanning fragments of human histone H4 were biotinylated enzymatically using biotinidase. Peptide-bound biotin was probed with streptavidin– peroxidase. Peptides based on the N-terminal sequence of histone H4 were effectively recognized by biotinidase as substrates for biotinylation; in contrast, peptides based on the C-terminal sequences were not biotinylated. …

Tyrosine B10 Inhibits Stabilization Of Bound Carbon Monoxide And Oxygen In Soybean Leghemoglobin, Suman Kundu, George C. Blouin, Scott A. Premer, Gautam Sarath, John S. Olson, Mark S. Hargrove

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

Detailed comparisons of the carbon monoxide FTIR spectra and ligand-binding properties of a library of E7, E11, and B10 mutants indicate significant differences in the role of electrostatic interactions in the distal pockets of wild-type sperm whale myoglobin and soybean leghemoglobin. In myoglobin, strong hydrogen bonds from several closely related conformations of the distal histidine (His^E7) side chain preferentially stabilize bound oxygen. In leghemoglobin, the imidazole side chain of His^E7 is confined to a single conformation, which only weakly hydrogen bonds to bound ligands. The phenol side chain of TyrB10 appears to “fix” the position of His …

Moisture Potential Affects Rate Of Leaf Appearance In Cool Season Grasses, Nina Cherone Terrell

McCabe Thesis Collection

The rate of leaf appearance and onset of growth in cool season grasses may be influenced by soil moisture potential and exposure to below freezing temperatures. Levels of moisture potential and days exposed to freezing temperatures, which will restrict leaf appearance, are not well defined. The first part of this study was to determine the effects of different moisture potentials on the leaf appearance rates in two cool season grasses. Italian ryegrass (IRG) and tall wheat grass (TWG) were grown hydroponically at 4 moisture potentials in seed pouches in an incubator under a photoperiod of 13 hours light and 11 …

National Science Foundation-Sponsored Workshop Report. Draft Plan For Soybean Genomics, Gary Stacey, Lila N Vodkin, Wayne A. Parrott, Randy C. Shoemaker

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

Recent efforts to coordinate and define a research strategy for soybean (Glycine max) genomics began with the establishment of a Soybean Genetics Executive Committee, which will serve as a communication focal point between the soybean research community and granting agencies. Secondly, a workshop was held to define a strategy to incorporate existing tools into a framework for advancing soybean genomics research. This workshop identified and ranked research priorities essential to making more informed decisions as to how to proceed with large scale sequencing and other genomics efforts. Most critical among these was the need to finalize a physical …

Cattle As Grazing Management And Seed Dispersal Tools For Increasing Native Species Diversity On Great Basin Rangelands, Marina K. Whitacre

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments evaluated: 1) the influence of seed intake and gut retention time on seed passage, recovery, and germinability; 2) fecal seeding and broadcast /trampling as techniques to incorporate seeds into a well-established Agropyron desertorum (Fisch.) Schult. stand in Skull Valley , Utah; 3) intensive grazing as a means to reduce Agropyron biomass and increase establishment and survival of seeded species; and 4) the recovery and germinability of seed extracted from dung collected from the field. Two shrubs (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young and Atriplex confertifolia Torr. & Frem.), a grass (Elymus elymoides (Raf.) …

Gene Expression Profiling Of Bovine Macrophages In Response To Escherichia Coli O157:H7 Lipopolysaccharide, Carol G. Chitko-Mckown, James M. Fox, Laura C. Miller, Michael P. Heaton, James L. Bono, James E. Keen, William M. Grosse, William W. Laegried

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

The aim of this study was to identify changes in bovine macrophage gene expression in response to treatment with Escherichia coli 0157:H7 lipopolysaccharide (LPS), utilizing a human gene microarray. Bovine cDNA from control and LPStreated primary macrophages hybridized to greater than 5644 (79.8%) of the non-control gene targets on a commercially available microarray containing greater than 7075 targets (Incyte Genomics, St. Louis, MO). Of these target sequences, 44 were differentially expressed upon exposure to LPS, including 18 genes not previously reported to exist in cattle. These included a pentaxin-related gene, CASP8, TNF-induced genes, interferon-induced genes, and inhibitors of apoptosis. Using …

Estimation Of Carbon Sequestration By Combining Remote Sensing And Net Ecosystem Exchange Data For Northern Mixed-Grass Prairie And Sagebrush–Steppe Ecosystems, E. Raymond Hunt Jr., Robert D. Kelly, William K. Smith, Jace T. Fahnestock, Jeffrey M. Welker, William A. Reiners

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

Carbon sequestration was estimated a northern mixed-grass prairie site and a sagebrush–steppe site in southeastern Wyoming using an approach that integrates remote sensing, CO₂ flux measurements, and meteorological data. Net ecosystem exchange (NEE) of CO₂ was measured using aircraft and ground flux techniques and was linearly related to absorbed photosynthetically active radiation (APAR). The slope of this relationship is the radiation use efficiency (ε = 0.51 g C/MJ APAR); there were no significant differences in the regression coefficients between the two sites. Furthermore, ecosystem chamber measurements of total respiration in 1998 and 1999 were used to develop …

Establishing Effects Of Application Of Swine Manure On Crop Leaf Damage To Growing Crops, Charles Shapiro, University Of Nebraska-Lincoln

Department of Agronomy and Horticulture: Faculty Publications

Swine manure from a below barn storage facility was applied to growing corn and soybeans to determine phytotoxic effects. The manure had an electrical conductivity of around 20 mmhos/cm and was diluted for treatment at full, half, quarter and none. The manure mixtures were applied at a rate of 0.5 in/acre using a procedure that wet the foliage three times in a 15-minute time span. Manure mixtures were applied at V7 and V14 for corn and V3 and R1 for soybeans. Phytotoxic effects were shown at the high rate for both crops, but soybeans were killed at the early application …

Intsormil 2004 Annual Report, John M. Yohe, Thomas Crawford Jr., Kimberly Christiansen, Joan Frederick

INTSORMIL Impacts and Bulletins

The 2004 INTSORMIL Annual Report presents the progress and notable achievements by the SorghumlMillet CRSP during the period of July 1, 2003 - June 30, 2004. These results are an outcome of partnerships between scientists at six U.S. Land Grant Universities (Kansas State University, Mississippi State University, University of Nebraska, Purdue University, Texas A&M University and West Texas A&M University) and scientists of the Agricultural Research Service of the U.S. Department of Agriculture at Tifton, Georgia and National Agricultural Research Systems (NARS) and National Universities in nineteen countries in Central America, West Africa, East Africa and Southern Africa.

Agricultural research …

Seed Quality Qtl In A Prominent Soybean Population, D. L. Hyten Jr., V. R. Pantalone, C. E. Sams, A. M. Saxon, D. Landau-Ellis, T. R. Stefaniak, M. E. Schmidt

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is a versatile crop due to its multitude of uses as a high protein meal and vegetable oil. Soybean seed traits such as seed protein and oil concentration and seed size are important quantitative traits. The objective of this study was to identify representative protein, oil, and seed size quantitative trait loci (QTL) in soybean. A recombinant inbred line (RIL) population consisting of 131 F6-derived lines was created from two prominent ancestors of North American soy-beans (‘Essex’ and ‘Williams’) and the RILs were grown in six environments. One hundred simple sequence repeat (SSR) markers …