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Nebraska’S Groundwater Legacy: Nitrate Contamination Beneath Irrigated Cropland, Mary E. Exner Spaulding, Aaron J. Hirsh, Roy F. Spalding

Department of Agronomy and Horticulture: Faculty Publications

A 31 year record of ~44,000 nitrate analyses in ~11,500 irrigation wells was utilized to depict the decadal expansion of groundwater nitrate contamination (N>10 mg/L) in the irrigated corn-growing areas of eastern and central Nebraska and analyze long-term nitrate concentration trends in 17 management areas (MAs) subject to N fertilizer and budgeting requirements. The 1.3 M contaminated hectares were characterized by irrigation method, soil drainage, and vadose zone thickness and lithology. The areal extent and growth of contaminated groundwater in two predominately sprinkler-irrigated areas was only ~20% smaller beneath well-drained silt loams with thick clayey-silt unsaturated layers and unsaturated …

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 …

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 …

Growing South Dakota (Winter 2014), College Of Agriculture &. Biological Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

This issue contains the 2013 SDSU Agricultural Experiment Station Annual Report

[Page] 2 The World’s First: Collaborative Effort Produces Multi-Hybrid Planter To Advance Precision Ag
[Page] 4 70 Years Of Data: Ranchers Benefit From Long-Term Grazing Studies
[Page] 6 Better Beef: Fetal Programming Study Analyzes Effects Of Cow Nutrition On Meat Quality
[Page] 7 Winter College News
[Page] 8 Consumer Sciences, Animal Health, Livestock Marketing: Important Research Continues In These Areas
[Page] 10 Improving Human Health: Role Of Nondigestible Fiber, Antioxidants Studied To Prevent Disease
[Page] 11 Food Safety Focus: Targeting Heat-Resistant Microbes To Improve Dairy Products
[Page] 12 Engineering …

Just Farming: An Environmental Justice Perspective On The Capacity Of Grassroots Organizations To Support The Rights Of Organic Farmers And Laborers, Rebecca Elaine Berkey

Antioch University Dissertations & Theses

This mixed methods study builds upon literature and research in environmental justice, public participation, and community development to examine how justice-related issues impact farmers and workers on organic farms in the Northeastern United States. It also examines how involvement in a grassroots organization helps farmers and workers address these issues. At the core of the study is an exploration of environmental justice and its applications at a broad, systemic level; an examination of the current context of laborers in organic agriculture in the Northeast; and finally an investigation of the effects of grassroots organizing within the Northeast Organic Farming Association …

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 …

Application Of Choice-Based Conjoint Analysis To Determine Consumers' Preferences And Willingness To Pay For Grass Fed Beef In The United States, Franklin Fernando Vaca Moran

LSU Doctoral Dissertations

U.S. consumption of beef has declined during the last three decades. Consumer preferences have shifted toward products that are considered healthy, environmentally friendly and obtained through sustainable production methods. Because of the characteristics of grass-fed beef production, consumers are becoming more interested in grass-fed beef products than conventional beef products. A choice-based experiment was used to assess consumer’s preferences for grass-fed beef. A national online survey was conducted in May 2012 and the information from 4000 respondents was collected from the entire U.S. The respondents were divided in two groups of similar size: grass-fed beef eaters, comprised by the respondents …

Three Essays On U.S. Meat Goat Production: Goal Structure, Selection Of Breeding Stock, And Meat Goat Marketing, Narayan Prasad Nyaupane

LSU Doctoral Dissertations

This study investigates three major areas of U.S. meat goat production – goal structure, selection of breeding stock, and marketing, by using survey data received from U.S. meat goat producers. Of 1,600 producers surveyed, 584 usable responses were obtained with an adjusted response rate of 43%. The fuzzy pair-wise comparison method was used to determine producer goal structure. The results showed that profit maximization and leisure-related goals were highly considered goals and controlling weeds/vegetation and increasing farm size were the least considered goals by U.S. meat goat producers. A choice-based conjoint study was conducted to identify producer preferences for meat …

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 …

Estimating U.S. Household Seafood Demand Based On Longitudinal And Cross-Sectional Data, Huabo Wang

LSU Doctoral Dissertations

This overall goal of this research is to examine and update U.S. at-home household demand estimates for seafood (including species and generic products) that can be used in policy formulation (by both the private and public sector). As such, this study estimated quantity-based household demand functions for seafood in aggregate, by generic product form (fresh, frozen, and prepared), and primary species. Given that the role of quality has been shown to significantly influence expenditures and seafood demand, this paper also seeks to incorporate the household quality choice into the demand model. In order to help to tailor the market strategy, …

Technology Use In Agriculture, Rebecca J. Vogt, Charlotte Narjes, Anne Byers, Connie Hancock

Cornhusker Economics

In September 2013, the Nebraska Broadband Initiative partnered with the Strategic Networks Group (SNG) to conduct an email survey of Nebraska businesses on their use of broadband technologies. Responses from over 800 Nebraska businesses show that broadband is being widely used and is benefitting businesses across the state. The complete report can be found online at http://broadband.nebraska.gov/. Seventy of those businesses self-reported being in the agriculture/forestry/fishing industry. This paper will take a closer look at the responses from this industry sector.

Effect Of Stocking Biomass On Solids, Phytoplankton Communities, Common Off-Flavors, And Production Parameters In A Channel Catfish Biofloc Technology Production System, Bartholomew W. Green, Kevin K. Schrader, Peter W. Perschbacher

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

The effect of initial channel catfish (Ictalurus punctatus, Rafinesque, 1818) fingerling biomass (1.4, 1.8, or 2.3 kg m^-3) on phytoplankton communities, common off-flavours and stocker catfish production parameters was evaluated in biofloc technology production tanks. Stocker catfish size (145.5–172.6 g fish^-1) at harvest did not differ among treatments, but net yield increased linearly as initial biomass increased (R² = 0.633). Mean total feed consumption increased linearly with initial catfish biomass (R² = 0.656) and ranged from 10.7 to 15.8 kg m ^-3. Total suspended solids (TSS) in all treatments increased linearly …

Fate Of Antimicrobials And Antimicrobial Resistance Genes In Simulated Swine Manure Storage, Stacey R. Joy, Xu Li, Daniel D. Snow, John Gilley, Bryan L. Woodbury, Shannon L. Bartelt-Hunt

School of Natural Resources: Faculty Publications

The behavior of three antibiotics (bacitracin, chlortetracycline, and tylosin) and two classes of antibiotic resistance genes (ARGs), tet and erm, were monitored in swine manure slurry under anaerobic conditions. First-order decay rates were determined for each antibiotic with half-lives ranging from1 day (chlortetracycline) to 10 days (tylosin). ARGs were monitored in the swine manure slurry, and losses of approximately 1 to 3 orders of magnitude in relative abundance were observed during the 40 day storage period. First-order degradation profiles were observed for chlortetracycline and its corresponding resistance genes, tet(X) and tet(Q). Tylosin was degraded to approximately 10% …

Using Plant Extracts To Reduce Asexual Reproduction Of Apple Scab (Venturia Inaequalis), János Bálint, Szilveszter Nagy, Rezso Thiesz, Imre-István Nyárádi, Adalbert Balog

Turkish Journal of Agriculture and Forestry

The aim our research was to develop effective methods for organic apple farming, based on the use of plant extracts to control the asexual reproduction of Venturia inaequalis. Plant extracts of artemisinin, chelidonine, thymol, and populin tested in vitro under laboratory conditions significantly slowed down the germination of V. inaequalis conidia. During a 2-year study under field conditions, the effect of 1% populin, an extract from black poplar buds, on apple scab was tested in parallel with synthetic fungicides and a no-pesticide regime on Golden Delicious and Jonathan apples. Populin significantly reduced the number of scabbed leaves and fruits on …

Extractability And Phytoavailability Of Cadmium In Cd-Rich Pedogenic Soils, Kürşad Özbek, Nesi̇me Cebel, İlhami̇ Ünver

Turkish Journal of Agriculture and Forestry

Conspicuous vegetation entities of pedogenic soils rich in cadmium and their diethylene triamine pentaacetic acid (DTPA)-extractable Cd content (DCd) under the temperate continental and Mediterranean climatic conditions of western Anatolia were determined. Foliage of herbaceous plants and nearby soil samples was collected from 51 zinc mining areas. DCd content was found to reach 11.6%-16.2% of the total Cd content, indicating more extractability than in many other heavy metals. Growth chamber and nursery experiments were conducted with the seeds collected. Dactylis glomerata and Galium tenuissimum subsp. tenuissimum, both common in grazing lands, were found to be accumulating 23.5 mg Cd kg^{-1} …

Assessment Of Density-Dependent Feeding Damage By The Cotton Dusky Bug, Oxycarenus Laetus Kirby (Hemiptera: Lygaeidae), In Cotton, Muhammad Ahsan Khan, Muhammad Dildar Gogi, Muhammad Hamid Bashir, Mubasher Hussain, Zain-Ul Abdin, Muhammad Aamir Rashid

Turkish Journal of Agriculture and Forestry

The dusky cotton bug, Oxycarenus laetus Kirby (Hemiptera: Lygaeidae), is a serious threat to cotton due to early cultivation of Bt cotton. These studies were carried out under laboratory and field conditions to estimate the feeding damage caused by O. laetus to seed weight, seed germination, and lint quality of cotton cultivar Bt-121 at 6 bug densities (0, 5, 10, 15, 20, and 25 adult pairs). The results revealed that seed germination and seed weight decreased, whereas percent reduction in seed germination and seed weight over control increased with increasing bug density. Bug density in the range of 5-25 pairs …

Durability Test On An Agricultural Tractor Engine Fuelled With Pure Biodiesel (B100), Marco Bietresato, Dario Friso

Turkish Journal of Agriculture and Forestry

The performance of a 118-kW tractor fuelled by pure biodiesel was monitored during a long-term field experiment with approximately 800 h of engine function. The objective was to demonstrate that B100, a pure biodiesel fuel, is a viable alternative to traditional diesel oil in terms of long-term mechanical reliability. A bench test on the new engine, performed by attaching a test stand to the power take-off of the tractor, showed an expected reduction in power (-9%) and torque (-7%) and an increase in specific consumption (+13%) when biodiesel was used as a complete substitute to diesel oil. Furthermore, with the …

Antioxidant And Radical Scavenging Activities In Fruits Of 6 Sea Buckthorn (Hippophae Rhamnoides L.) Cultivars, Otakar Rop, Sezai̇ Erci̇şli̇, Jiri Mlcek, Tunde Jurikova, Ignac Hoza

Turkish Journal of Agriculture and Forestry

Sea buckthorn (Hippophae rhamnoides L.) is a minor fruit crop. The most important breeding activities focused on the production of sea buckthorn fruits as a top-quality food product have been performed in Russia, Germany, and the Czech Republic. Over the past several decades, plant breeders have selected a number of cultivars that show excellent physical and nutritional properties. The aim of this study was to monitor and determine the total contents of phenols and flavonoids as well as antioxidant capacity and scavenging activity of methanolic extracts on reactive oxygen species and lipid peroxidation in some cultivars of sea buckthorn suitable …

The Choice Of Auxin Analogue For In Vitro Root Induction Influences Post-Induction Root Development In Eucalyptus Grandis, Muhammad Nakhooda, Maria Paula Watt, David Mycock

Turkish Journal of Agriculture and Forestry

Previous studies on in vitro rooting for improved micropropagation of eucalypts indicated that root graviperception and post-acclimatisation architecture are determined by the relative exogenous auxin analogue and its stability, supplied during the pre-rooting culture stages. The specific roles of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) in the rooting medium on the in vitro root morphological processes were explored using a good-rooting clone. In vitro rooting percentage was significantly reduced when either of the auxin inhibitors 2,3,5-triiodobenzoic acid (TIBA) and ρ-chlorophenoxyisobutyric acid (PCIB) or the auxin antagonist kinetin was supplied at rooting, with or without exogenous auxin. For all treatments, …

The Effects Of Land Use And Land Cover Changes (Lulcc) In Kuseyr Plateau Of Turkey On Erosion, Emre Özşahi̇n, Veli̇ Uygur

Turkish Journal of Agriculture and Forestry

Erosion is one of the important problems in degradation of agricultural lands and other natural lands. The most dynamic factor in controlling erosion is land cover, and this factor has been anthropogenically manipulated for ages. This study investigates the effect of land use and land cover changes (LULCC) on erosion at Kuseyr Plateau, which is situated in the southernmost part of the eastern Mediterranean basin, Turkey. A geographical information systems-based method using the revised universal soil loss equation (3D) was employed to identify the amount of annual soil loss, erosion risk classes, and distribution generated by LULCC. Landsat satellite images …

Germination And Electrical Conductivity Tests On Artificially Aged Seed Lots Of 2 Wall-Rocket Species, Simona-Laura Lazar, Sara Mira, Doru Pamfil, Juan Bautista Martinez-Laborde

Turkish Journal of Agriculture and Forestry

The aim of this study was to determine whether the loss of germinability and vigour in wall-rocket seed lots was related to electrolyte leakage. Ten seed lots of 2 wall-rocket species (9 of Diplotaxis tenuifolia and one of D. erucoides (Brassicaceae)) were stored at 45 °C and 70% relative humidity and electrolyte leakage was measured using the conductivity test. Small differences in longevity were found among species or seed lots, suggesting that a similar relative longevity might be expected within the genus Diplotaxis after artificial ageing, and that it will be above the average of that found in other species …

The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman

Honors Projects

Lake Erie has experienced harmful algal blooms with increased frequency since the mid-1990s due to excess nutrients from Rivers, such as the Maumee River, and largely agricultural watersheds. Nonpoint source pollution from agriculture contributes to eutrophication, algal blooms, and the degradation of water quality. This creates stress on aquatic fauna, reduced aesthetic quality, odor, and limits of the water for usage of drinking, recreation, and industry. This research paper asks what the contributions of having access to manure application records, soil records, and information about antibiotics have on what is known about manure management and antibiotic resistance, which has been …

Variation In Soil C And Microbial Functions Across Tree Canopy Projection And Open Grassland Microenvironments, Roberto Lai, Alessandra Lagomarsino, Luigi Ledda, Pier Paolo Roggero

Turkish Journal of Agriculture and Forestry

Mixtures of grasslands and perennial woody crops or vineyards represent a major source of potential carbon storage or release. Understanding the spatial variability of soil properties in these ecosystems is important in determining soil constraints related to the management of soil resources. The aims of the study were 1) to explore the spatial variability associated to the trees for soil C storage and its components and reactivity; and 2) to assess the similarities between microenvironments in terms of microbial functional diversity. Eight microenvironments characterized by different long-term soil management practices and different positions with respect to woody plant canopy soil …

Socially Disadvantaged Farmer Issues Can Be Addressed When Diverse Frontline Agricultural Workers Proactively Work Together, Walter A. Hill, Jillian Hishaw, Tasha M. Hargrove

Professional Agricultural Workers Journal

This paper focuses on socially disadvantaged farmers (SDFs) and civil rights issues as it relates to the USDA. It also deals with Diversity Initiatives in the 2008 Farm Bill, and discusses an assessment by Jackson Lewis LLC of the USDA’s efforts to deal with the diversity initiatives. Redacted USDA case studies examined at the 2010 Professional Agricultural Workers Conference at Tuskegee University are presented. The findings revealed that at that time the 2008 Farm Bill Initiatives were not effectively being implemented. It was recommended that the USDA should: keep making the effort to reform or improve its civil rights practices; …

Community Capital And Local Economic Development Efforts, Andrew A. Zekeri

Professional Agricultural Workers Journal

Actions by local groups and leaders constitute an essential but poorly understood element of many rural economic development efforts. Previous studies suggest that local development efforts can influence community changes, but questions remain about why localities differ in economic development efforts. Drawing upon community capital framework and human ecological theory, the purpose of this research was to examine the effects of community capital on economic development efforts in rural communities. Hierarchical regression results indicate that social capital, cultural capital, built capital significantly predict economic development effort to develop recreation and tourism and human services. Despite that, only built capital and …

Sustainable Management Of The Main Two Maltese Indigenous Grape Varieties For Winemaking, Jonathan Falzon

Masters Theses, 2010-2019

Ġellewża and Girgentina, the main two Maltese indigenous grape varieties that are used for winemaking, are grown in small parcels of land with an average size just over 0.1 ha. Policies and regulations that influence the sector have been set up and this increased the need for studies to understand the current management practices and how can they be more sustainable. Through interviews with 30 growers of the indigenous grape varieties it was found that most vines are trained as bush vines and cane pruned with 2 or 3 canes with about 5 to 10 buds in each. Nutrition is …