Agriculture Commons^™

Predicting Phosphorus Dynamics In Complex Terrains Using A Variable Source Area Hydrology Model, Amy S. Collick, Daniel R. Fuka, Peter J.A. Kleinman, Anthony R. Buda, Jennifer L. Weld, Mike J. White, Tamie L. Veith, Ray B. Bryant, Carl H. Bolster, Zachary M. Easton

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

Phosphorus (P) loss from agricultural watersheds has long been a critical water quality problem, the control of which has been the focus of considerable research and investment. Preventing P loss depends on accurately representing the hydrological and chemical processes governing P mobilization and transport. The Soil and Water Assessment Tool (SWAT) is a watershed model commonly used to predict run-off and non-point source pollution transport. SWAT simulates run-off employing either the curve number (CN) or the Green and Ampt methods, both assume infiltration-excess run-off, although shallow soils underlain by a restricting layer commonly generate saturation-excess run-off from variable source areas …

Nucleotide Polymorphism And Copy Number Variant Detection Using Exome Capture And Next-Generation Sequencing In The Polyploid Grass Panicum Virgatum, Joseph Evans, Jeongwoon Kim, Kevin L. Childs, Briaenne Vaillancourt, Emily Crisovan, Aruna Nandety, Daniel J. Gerhardt, Todd A. Richmond, Jeffery A. Jeddeloh, Shawn M. Kaeppler, Michael D. Casler, C Robin Buell

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

Switchgrass (Panicum virgatum) is a polyploid, outcrossing grass species native to North America and has recently been recognized as a potential biofuel feedstock crop. Significant phenotypic variation including ploidy is present across the two primary ecotypes of switchgrass, referred to as upland and lowland switchgrass. The tetraploid switchgrass genome is approximately 1400 Mbp, split between two subgenomes, with significant repetitive sequence content limiting the efficiency of re-sequencing approaches for determining genome diversity. To characterize genetic diversity in upland and lowland switchgrass as a first step in linking genotype to phenotype, we designed an exome capture probe set based on transcript …

Complete Genome Sequence Of Mycobacterium Avium Subsp. Paratuberculosis, Isolated From Human Breast Milk, John Bannantine, Lingling Li, Michael M. Mwangi, Rebecca Cote, Juan Antonio Raygoza Garay, Vivek Kapur

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

Mycobacterium avium subsp. paratuberculosis causes Johne’s disease (JD) in cattle, sheep, goats, and other ruminant animals. JD presents as a chronic granulomatous intestinal infection with a worldwide distribution and imposes a significant economic toll on livestock industries (1). M. avium subsp. paratuberculosis has a complex cell wall structure containing mycolic acids and several lipids similar to those of other members of this genus, yet it is the most slowly growing member. This bacterium often requires 8 to 16 weeks before colonies are visible in culture, which is a major hurdle in diagnostics and therefore in the implementation of optimal JD …

Draft Genome Sequence Of A Mycobacterium Avium Complex Isolate From A Broadbill Bird, John Bannantine, Darrell O. Bayles, Suelee Robbe-Austerman, Angela M. Burrell, Judith R. Stabel

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

Mycobacterium avium complex (MAC) organisms cause opportunistic infections in humans, yet their epidemiology remains poorly understood. They are slowly growing environmental and animal-associated mycobacteria that have little notoriety except for the strains that cause disseminated infections in HIV- infected humans (1). Most MAC organisms are classified taxonomically as a single species, M. avium, which is divided into at least four subspecies, M. avium subsp. avium, M. avium subsp. hominissuis, M. avium subsp. paratuberculosis, and M. avium subsp. silvaticum (2). The only other species in this group is M. intracellulare. Genotyping of this diverse bacterial group has been achieved using intergenic …

Russian Olive Control - Cut Stump Treatment, Ron Patterson, Dennis Worwood

All Current Publications

This fact sheet discusses cut stump herbicide treatment, which can be used to control Russian olive at any time of the year.

Exposure Of Feral Swine (Sus Scrofa) In The United States To Selected Pathogens, John A. Baroch, Carl A. Gagnon, Sonia Lacouture, Marcelo Gottschalk

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine (Sus scrofa) are widely distributed in the United States. In 2011 and 2012, serum samples and tonsils were recovered from 162 and 37 feral swine, respectively, in the US to evaluate exposure to important swine endemic pathogens. Antibodies against porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) were found in 2.5% and 25.3% of tested sera, respectively. Positive serological reactions against Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae have been detected in 19.7% and 69.7% of animals. More than 15% of animals presented antibodies against these 2 pathogens simultaneously. Most animals were also seropositive for …

Compost Bedded Pack Barns For Dairy Cattle: Bedding Performance And Mastitis As Compared To Sand Freestalls, Elizabeth A. Eckelkamp

Theses and Dissertations--Animal and Food Sciences

Lameness and mastitis are the two most costly diseases in the dairy industry. Reduction of these diseases through housing and management is beneficial. Compost bedded pack (CBP) and sand freestall barns were compared in a long-term, on-farm study to assess the effect of housing on each disease. Another research objective was to evaluate the effects of ambient weather conditions on moisture and 20 cm internal temperature of CBP. Compost bedded pack moisture, C:N ratio, and internal temperature effects on cleanliness, mastitis, and bedding bacterial counts were also considered. The last research objective was to evaluate the economics of bedding material …

Carbon Farming In Relation To Western Australian Agriculture, Robert Sudmeyer, Jackson Parker, Tanmoy Nath, Ananda Ghose

Bulletins 4000 -

Carbon farming activities need to return multiple economic and environmental co-benefits to be attractive to land managers. This bulletin summarises concepts underlying carbon farming, how Australia accounts for greenhouse gas emissions and the potential for Western Australian land managers to participate in, and benefit from, carbon farming.

Water Demand On Center-Pivot Irrigated Crops In Alabama, Robert Rossell

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Common Sunflower Seedling Emergence Across The U.S. Midwest, Sharon A. Clay, Adam Davis, Anita Dille, John Lindquist, Analiza H. M. Ramirez, Christy Sprague, Graig Reicks, Frank Forcella

Department of Agronomy and Horticulture: Faculty Publications

Predictions of weed emergence can be used by practitioners to schedule POST weed management operations. Common sunflower seed from Kansas was used at six Midwestern U.S. sites to examine the variability that 16 climates had on common sunflower emergence. Nonlinear mixed effects models, using a flexible sigmoidal Weibull function that included thermal time, hydrothermal time, and a modified hydrothermal time (with accumulation starting from January 1 of each year), were developed to describe the emergence data. An iterative method was used to select an optimal base temperature (T_b) and base and ceiling soil matric potentials (ψ_b and …

Constructing A Block And Fence Growing Bench For Use With A Capillary Mat Irrigation System For Greenhouse Plant Production, Stacy A. Adams, Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

Plant health and productivity of greenhouse grown plants are improved when grown on raised benches where they can have optimal environmental conditions. Often seasonal plant growers set plants directly on the greenhouse floor which is less than optimum due to temperature stratification, cold drafts, poor air movement, and wet conditions. This publication describes how to construct simple and economical growing benches and a irrigation system useful for the specialty crop grower.

Evaluation Of Soilless Media Sensors For Managing Winter-Time Greenhouse Strawberry Production Using A Capmat System, George E. Meyer, Ellen T. Paparozzi, Stacy A. Adams, Diego Scacalossi Voltan

Department of Agronomy and Horticulture: Faculty Publications

It is important for a greenhouse strawberry grower to know that their capillary mat (CapMat™) fertigation system is working correctly and that plants are receiving the correct amounts of water and fertilizer. Pots with soilless mix are not expected to hold more than 70% water on a volumetric basis. Pots with less than 40% water content continuously are not supplied enough water and nutrients to the plants. Typically, pots located near the manifold distribution system get a little more water than those at the other locations, but water use will really vary according to the factors listed above as well …

A Quantitative Analysis Of The Effect Of Cash-4-Grass Programs On Water Consumption, Cynthia Allen

Walden Dissertations and Doctoral Studies

Water supplies in California are stretched to critical levels as a result of population growth, periodic drought, and climate change. The California legislature recognized that the best way to increase supply is to decrease demand so the Water Use Efficiency Senate Bill 7 (SBx7-7) was signed into law in 2009. The law requires water purveyors to reduce per capita water usage by 20% by the year 2020. To comply, water purveyors are searching for innovative ways to increase water conservation. A review of the literature has shown that many factors influence water consumption. However, the majority of household water consumption …

Tall Fescue Ergovaline Concentration Based On Sample Handling And Storage Method, Krista La Moen Lea

Theses and Dissertations--Plant and Soil Sciences

Ergovaline is produced by the endophyte Neotyphodium coenophialum (Morgan-Jones and Gams) in tall fescue (Schedonorus arundinacea (Schreb.) Dumort. = Festuca arundinacea Schreb.) and is blamed for a multitude of costly livestock disorders. Testing of pastures is common in both research and on farm situations. Since ergovaline is known to be unstable and affected by many variables, the objective of this study was to determine the effect of sample handling and storage on the stability of this compound. Homogeneous milled tall fescue sub-samples were analyzed for ergovaline concentration using HPLC after a range of sample handling procedures or storage. Ergovaline …

Fusarium Head Blight Resistance And Agronomic Performance In Soft Red Winter Wheat Populations, Daniela Sarti Dvorjak

Theses and Dissertations--Plant and Soil Sciences

Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schwein.(Petch)], is recognized as one of the most destructive diseases of wheat (Triticum aestivum L. and T. durum L.) and barley (Hordeum vulgare L.) worldwide. Breeding for FHB resistance must be accompanied by selection for desirable agronomic traits. Donor parents with two FHB resistance quantitative trait loci (QTL) Fhb1 (chromosome 3BS) and QFhs.nau-2DL (chromosome 2DL) were crossed to four adapted SRW wheat lines to generate backcross and forward cross progeny. F₂ individuals were genotyped and assigned to 4 different groups according to presence/ absence of …

Switchgrass Yield And Quality With Multiple Fertilizer Applications And Harvest Dates, Thomas Clarkson Keene

Theses and Dissertations--Plant and Soil Sciences

Switchgrass (Panicum virgatum L.) is an important native warm-season grass for biomass and forage production in the U.S. This research determined the effect of fertilizer type (conventional, manure, and biosolids) and rate on switchgrass biomass yield and forage quality. Fertilizers were added at 0, 33, 67, 100, and 134 kg N ha^-1 on established stands of ‘Kanlow’ switchgrass in three northeastern Kentucky counties. Soils across sites ranged from recently cleared forestland (low pH, P, and K) to productive cropland (high pH, P and K). Stands were sampled for forage nutritive value in June, simulating a hay harvest. Nutritive …

Plant Growth Regulators And Herbicides For Management Of Poa Annua: Impact Of Biotypes And Behavior Of Flurprimidol In Turfgrass Species, Alexandra Perseveranda Williams

Theses and Dissertations--Plant and Soil Sciences

In 2011, Poa annua L. (Poa) biotypes were collected from greens of two golf courses in Lexington, Kentucky: 1.) The Lexington Country Club (LCC) and 2.) The University Club (UC). The samples were collected based on exhibiting one of two appearances while on the same green: 1.) dark green, with few to no flower heads (dark biotype) or 2.) light green, with numerous flower heads (light biotype). Two PGRs, paclobutrazol and flurprimidol, and two herbicides, bispyribac-sodium and amicarbazone, were applied to the plants both in the field and the greenhouse. Quality ratings were recorded weekly in both the …

C And N Cycling Dynamics And Microbial Community Composition In High Tunnel Production Systems, Kavita Lakshmi Mizin

Theses and Dissertations--Plant and Soil Sciences

Across the United States, high tunnels are used as a means of season extension and control over climatic variability in fruit and vegetable production. However, high tunnel systems are an intensive form of agricultural production which may compromise soil and crop quality over time. This study examined the effects of the varying environmental conditions, created in two types of tunnel system, movable and stationary, on the flow of nitrogen from amendment to plant and impact on crop and soil quality parameters. The way nutrients cycled through these systems was different and the nutrient treatments had no consistent effects on soil …

The Influence Of Tall Fescue Cultivar And Endophyte Status On Root Exudate Chemistry And Rhizosphere Processes, Jingqi Guo

Theses and Dissertations--Plant and Soil Sciences

Tall fescue (Lolium arundinaceum (Schreb.) Darbysh.) is a cool-season perennial grass used in pastures throughout the Southeastern United States. The grass can harbor a fungal endophyte (Epichloë coenophiala) thought to provide the plant with enhanced resistance to biotic and abiotic stress. However, the alkaloids produced by the common variety of the endophyte cause severe animal health issues resulting in a considerable amount of research focused on eliminating the toxic class of alkaloids while retaining the positive abiotic and biotic stress tolerance attributes of the other alkaloids. In doing so, very little attention has been paid to the …

Screening Of Mycobacterium Avium Subsp. Paratuberculosis Mutants For Attenuation In A Bovine Monocyte-Derived Macrophage Model, Elise A. Lamont, Adel M. Talaat, Paul M. Coussens, John Bannantine, Yrjo T. Grohn, Robab Katani, Ling-Ling Li, Vivek Kapur, Srinand Sreevatsan

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

Vaccination remains a major tool for prevention and progression of Johne’s disease, a chronic enteritis of ruminants worldwide. Currently there is only one licensed vaccine within the United States and two vaccines licensed internationally against Johne’s disease. All licensed vaccines reduce fecal shedding of Mycobacterium avium subsp. paratuberculosis (MAP) and delay disease progression. However, there are no available vaccines that prevent disease onset. A joint effort by the Johne’s Disease Integrated Program (JDIP), a USDA-funded consortium, and USDA—APHIS/VS sought to identify transposon insertion mutant strains as vaccine candidates in part of a three phase study. The focus of the Phase …

United States Meat Goat Production Economic Performance Measures: A Stochastic Production Frontier Analysis, Berdikul Qushim

LSU Doctoral Dissertations

The meat goat industry is relatively a newcomer to the U.S. agricultural production and one of the fastest growing livestock industries in the U.S. Despite the growth of the meat goat industry, little is known about meat goat production economics. Information is needed concerning the drivers of production efficiency, optimum size of operation, and scope economies in the industry. A nationwide mail survey of U.S. meat goat producers who advertise their meat goat production via the internet for this efficiency analysis was conducted. Costs and returns data for 2011 expenses from those meat goat producers were collected. This survey was …

Analysis Of Media Coverage Of Selected Food Safety Events On The Demand For The Recalled Products, Abhishek Bhagwat Bharad

LSU Doctoral Dissertations

The major focus of this study was to identify the linkage between information and consumer behavior and to examine the role that a new media index played in the identifying the tone of news stories. Past studies have relied on using the number of media stories but, this study tests a new approach, i.e., in order to analyze the effect of information by incorporating the sentiment indices. These indices were created based on the tone of the news story. The results from sentiment indices were compared to the results from the information index. Barten’s Synthetic model (BSM) was used to …

A Vision Of Capitalism, As It Was Meant To Be: A Social Purpose Business Plan For Foodshed Productions, August Miller

Capstone Collection

FoodShed Productions, a social enterprise is pursuing a mission: to raise the caring capacity of communities and resilience of our local environments through resident education in organic backyard farming. As a social enterprise, FoodShed Productions, a for-profit, earns its economic viability doing work more often associated with non-profits, measuring its worth by the social, environmental, and economic benefits of its operations. The communities in Boulder County, CO. are served by FoodShed Productions through a social process in which “We Build, We Coach, You Keep Growing,” toward the goal of self-reliance.

The topic of this CLC is a Social Purpose Business …

Soil Microbial Community Distributions And Disease Suppressiveness In The Coastal Plain Of Georgia, Michael J. Sabula

College of Graduate Studies: Theses & Dissertations

This study compared the soil microbial communities of three vegetation types in the coastal plain of Georgia: 1. crop land actively in use for agricultural production, 2. transitional grassland in early stages of secondary succession, and 3. pristine unmanaged forest land. Microbial species diversity and quantities of microbial DNA were determined from each of these vegetation types at three separate locations near Statesboro, Georgia. Length heterogeneity PCR(LH-PCR) methods and subsequent analysis of fungal, bacterial, and metazoan communities by analysis of similarity (ANOSIM) revealed high within-group similarity by vegetation type, indicating land management intensity and vegetation cover is a strong determining …

Community Vitality Connects Nebraska, Charlotte Narjes, Connie Hancock

Cornhusker Economics

Fostering the future of Nebraska is the underlying mission of the newly formed Community Vitality Initiative (CVI) launched by UNL Extension. The Community Vitality Initiative is focused on expanding partnerships to build communities where businesses thrive, entrepreneurs have access to the resources they need and young people want to return. Currently multi-disciplinary teams include faculty from the Departments such as Ag Economics and the Department of Child, Youth and Family Studies and will include faculty from all the University campuses and service providers from outside of the University.

Five Things You Probably Don’T Know About Handshake Farm Leases, J. David Aiken

Cornhusker Economics

Around half of Nebraska farmland is leased but there are some things you probably don’t know about leases that you probably should be aware of.

So, there some things that most folks probably don’t know about ag leases?

Yes. But I want to emphasize up front that smart tenants realize that if they push their legal rights to the limit, they probably will lose the lease in the end. That being said, landlords probably have narrower legal rights than they thought under handshake (i.e. unwritten) agricultural leases in Nebraska.

An Environment And Cultural Heritage Workbook For Students And Teachers, Rebecca Zarger, Kristina Baines

Open Educational Resources

The word "heritage" is one that means many things to many people. It often brings to mind things like food, language, clothing, or other traditions that are passed on from generation to generation. But it also includes places, buildings, art, values, and ways of making a living in particular environments. In Maya communities, as is the case elsewhere around the world, cultural practices and the environment are tightly connected, with one shaping the other.

With this workbook we take a broad view of heritage, one that links cultural and environmental histories, landscapes, and practices together. A term that UNESCO and …

Glyphosate Resistant Weeds - Beat Them Before They Beat You, Sally Peltzer

Grain and other field crops published reports

Herbicide resistance develops if the weeds exist in the population and set fertile seed. Being vigilant, keeping weed populations low and stopping seed set is the best way to prevent glyphosate resistance development:

• know the herbicide use history of each paddock. If glyphosate has been the dominant knockdown and spray-topping product used, it's time to change
• conduct herbicide resistance testing to determine what herbicides are effective on key weeds
• aim for maximum control
• establish a more diverse rotation to increase the number of control tactics available
• use non-herbicide control tactics at every opportunity
• always monitor the success of each control …

International Perspectives On Sustainable Agriculture In Cuba, B. Danielle Smith

University Honors Theses

Since the economic crisis following the collapse of the Soviet Union, Cuba has restructured their agriculture with a greater focus on domestic production of domestically consumed produce, and a dramatic reduction of petroleum products in all aspects of food production. This overhaul has included the broad application of what is termed agroecology – agricultural practices which focus on principles of biodiversity and sustainability – and inter-farm cooperation facilitated by the National Association of Small Farmers (ANAP) and Campesino a Campesino. Academics and journalists from within and abroad have critically examined aspects of the novel reforms developed in the country …

Strengthening Nebraska Businesses, Charlotte Narjes, Anne Byers

Cornhusker Economics

The Nebraska Broadband Initiative in 2013 launched a new effort to help Nebraska businesses increase their economic vitality by understanding how to more effectively use broadband technologies. Key points of this initiative include:

Benchmarking Data: Gather data through a business assessment to establish initial benchmarks and measure impact.

Providing Resources to Businesses: Help individual businesses understand how they can use broadband to increase their economic vitality, understand their Return on Investments (ROI) and assist them in identifying steps for implementation.

Building Capacity: Build capacity in Nebraska for business coaches (i.e., economic developers, extension educators and Department of Economic Development field …