Digital Commons Network^™

Validation Of Soil-Test-Based Phosphorus And Potassium Fertilizer Recommendations For Rice And Soybean, Matthew Scott Fryer

Graduate Theses and Dissertations

The science of soil-testing for nutrient management and fertilizer recommendations is widely accepted among scientists and agronomists. Although this science is unsurpassed in predicting soil nutrient availability, soil-test interpretations are seldom validated. Major research objectives for irrigated soybean [Glycine max (L.) Merr.] and direct-seeded, delayed-flood rice (Oryza sativa L.) were to: i) validate the accuracy of Mehlich-3 soil-test P (STP) and K (STK) interpretations and ii) published critical tissue-P and -K interpretations in predicting the yield response to fertilizer at different significance levels (p≤0.05 to 0.25), iii) examine how seed nutrient concentrations are influenced by fertilization and crop response to …

Analysis Of Ac/Ds Activation Tagged Mutants In Tomato (Solanum Lycopersicum), Ipeleng Randome

Graduate Theses and Dissertations

Tomato (Solanum lycopersicum) is a crop of immense economic and nutritional importance worldwide and also a good model organism for genomic studies of other dicot species. The recent completion of the tomato genome sequence is a great milestone towards learning about the tomato genome. Elucidation of the function of the different genes using different functional genomic tools is therefore important in adding to this resource. To this end, we have developed an Ac-Ds transposon ‘activation tagging’ (ATag) system to be able to transpose transposon inserts, bearing a strong 35S-enhancer element, all around the genome. An Ac-Ds ATag construct was used …

Maternal Denning Phenology And Substrate Selection Of Polar Bears (Ursus Maritimus) In The Southern Beaufort And Chukchi Seas, Jay Wesley Olson

Theses and Dissertations

Loss of sea ice due to global warming may affect the phenology and distribution of polar bear (Ursus maritimus) denning by altering access to denning habitats. We examined trends in the selection of maternal denning substrate (land versus sea-ice denning) in the southern Beaufort Sea (SB), addressing the potential influence of summer land-use and fall sea-ice conditions on substrate selection. We developed an algorithm based on statistical process control methods to remotely identify denning bears and estimate denning phenology from temperature sensor data collected on collars deployed 1985–2013 in the SB and Chukchi Sea (CS). We evaluated cub …

Mountain Big Sagebrush (Artemisia Tridentata Ssp Vaseyana) Seed Production, Melissa L. Landeen

Theses and Dissertations

Big sagebrush (Artemisia tridentata Nutt.) is the most widespread and common shrub in the sagebrush biome of western North America. Of the three most common subspecies of big sagebrush (Artemisia tridentata), mountain big sagebrush (ssp. vaseyana; MBS) is the most resilient to disturbance, but still requires favorable climactic conditions and a viable post-fire seedbank for successful unassisted recovery. This study was designed to assess MBS seed production throughout post-fire recovery. We performed 2 pilot studies to develop methods for estimating seed production and plant age. The results of the pilot studies and a space-for-time substitution strategy were used to measure …

The Detection And Characterization Of Some Viruses Infecting Blackberry And Cherry In South Carolina, Bindu Poudel

All Dissertations

Three separate virus research projects were conducted. Blackberry yellow vein disease (BYVD), a disorder caused by virus complexes, has become a major threat to blackberry production in the United States, especially in the southeastern part of the country where blackberries are grown for the fresh market. More than 30 viruses have been found to be associated with the disease. Most of these induce no symptoms when infecting the plant alone. However, when more than a single virus is present in the host visible symptoms are displayed. The incidence of 6 different viruses (Blackberry yellow vein-associated virus, Blackberry virus Y, Blackberry …

Sage-Grouse Nests In An Active Conifer Mastication Site, Charles P. Sandford, David K. Dahlgren, Terry A. Messmer

The Prairie Naturalist

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) have experienced long-term range-wide population declines and now may occupy less than 50% of their historic range (Schroeder et al. 2004). Conifer encroachment into sagebrush (Artemisia spp.) habitat was identified as a major conservation threat by the United States Fish and Wildlife Service (USFWS) as the agency reviewed the listing status of the species for possible protection under the Endangered Species Act of 1973 (USFWS 2013).

Conifer encroachment into sagebrush habitats negatively impacts sage-grouse at landscape scales (Doherty et al. 2008, Casazza et al. 2011, Baruch-Mordo et al. 2013). Sage-grouse will utilize …

Predicting Invasive Range Of Eucalyptus Globulus In California, Anthony J. Lopez

Master's Theses

Eucalyptus globulus is the subject of intense debate in California. Its invasive potential, aggressive growth, reproductive biology, and association with fire make the prediction of spread important in California. Two modeling simulations, Climex and Maxent, will illustrate the distribution and potential growth range of E. globulus in California based on climate and presence. Modeling the potential range of growth will predict invasive spread. The anticipated result is the continued spread of E. globulus in coastal regions with adequate moisture and suitable climate. Predicting the range of E. globulus in California dictates management strategy and is key for preventing further introduction, …

Optimizing A Luciferase-Based Tool For Studying The Effects Of Fatty Acid Desaturase 7 On Singlet Oxygen Accumulation In Arabidopsis Thaliana, Abeer Muhammedali Alnasrawi

Graduate Theses and Dissertations

In plants, reactive oxygen species (ROS) are generated as a byproduct of normal metabolism, as well as in response to adverse conditions such as light stress, extreme temperatures, and exposure to pests and pathogens. Singlet oxygen (1O2) is a ROS that is formed during photosynthesis in photosystem II (PSII) of the chloroplasts. Levels of 1O2 and other ROS are tightly controlled in healthy plants, but some studies suggest that levels of fatty acid desaturase (FAD) activity in Arabidopsis thaliana can influence constitutive and/or stress-responsive ROS accumulation. In this study, a luciferase-based reporter gene that is selectively stimulated by 1O2 (AAA-ATPase: …

The Effects Of Foliar Nutrient Applications On Split, Yield, And Internal Fruit Quality Of 'Wonderful' Pomegranate (Punica Granatum L.), John Matthew Chater

Master's Theses

Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO_{4 …}

Field Screening Of Diverse Soybean Cultivars For Flood Tolerance, Jane Achando Khatenje Mokua

Graduate Theses and Dissertations

Flooding can significantly reduce soybean growth, development, and yield. Therefore, screening and identification of flood-tolerant soybeans will enhance development of cultivars that are well suited for flood-prone areas. Sets of screening tests were conducted in Stuttgart, Arkansas using three separate but related experiments, with the purpose of establishing effective flood tolerance screening protocol that can identify tolerant and sensitive cultivars. Each experiment was completely randomized with three replications. The first experiment involved screening of 256 maturity group (IV and V) cultivars. Flooding was imposed at the fifth-node (V5) or first-bloom (R1) stage for ten days. Post-flood visual ratings and stand …

Storage Of Round And Square Switchgrass Bales: Effect Of Storage Time And Fungal Inoculation On Saccharification Efficiency, Noaa Frederick

Graduate Theses and Dissertations

To produce fermentable sugars from lignocellulosic biomass feedstock, severe pretreatment conditions are needed (either high acid concentration, temperature, or retention times). High severities can produce toxic byproducts which inhibit enzymatic hydrolysis or fermentation. In order to reduce pretreatment severities (and thus increase enzyme and fermentation efficiency), the white-rot fungus Pleurotus ostreastus was seeded into square and round bales of Kanlow switchgrass (Panicum virgastum L.) and left in the field over a period of 9 month. The laccase producing fungus is believed to selectively degrade lignin, a common plant structural polymer, which can function as an enzymatic inhibitor. Samples were taken …

The Effect Of Alternative Fertilization And Application Time On Voluntary Intake Of Forages, Jessica Clark

Graduate Theses and Dissertations

Dairy slurry and poultry litter have increased in popularity as fertilizers in the agriculture industry. However, residual effects of these manures on voluntary intake of forages from subsequent harvests are not well known. The objectives of this two part study were to determine if moisture level of alfalfa silage and the use of dairy slurry as a fertilizer have an effect on intake and digestibility by sheep, and if forage species and the use of poultry litter as a fertilizer have an effect on intake by horses. Eighteen ewes (47.6 ± 5.34 kg) were used in experiment 1 and were …

Distribution Of Herbicide-Resistant Shattercane And Johnsongrass Populations In Sorghum Production Areas Of Nebraska And Northern Kansas, Rodrigo Werle, Amit J. Jhala, Melinda K. Yerka, J. Anita Dille, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Overreliance on acetolactate synthase (ALS)-inhibiting herbicides for weed control during the 1990s resulted in selection of ALS-resistant shattercane [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet ex Davidse] biotypes in Nebraska. The objective of this study was to assess the baseline presence of ALS-resistance in 190 shattercane and 59 johnsongrass [Sorghum halepense (L.) Pers.] populations collected across northern Kansas, northwestern Missouri, and southern Nebraska in 2013. In 2014, a preliminary field experiment was conducted to evaluate the presence of herbicide resistance in the aforementioned populations. Treatments consisted of four herbicides (clethodim {2-[1-[[(E)-3-chloroprop-2-enoxy]amino] propylidene]-5-(2-ethylsulfanylpropyl)cyclohexane-1,3-dione}, glyphosate [N-(phosphonomethyl) …

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …

Effects Of Control Release Fertilizers On Nutrient Leaching, Palm Growth And Production Cost, Pushpa Soti, Angie Fleurissaint, Stewart Reed, Krish Jayachandran

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Objective of this study was to evaluate the effect of different controlled release fertilizer technologies on nutrient leaching and plant growth parameters of two palm species, Chinese Fan (Livistona chinensis) and Queen (Syagrus romanzoffiana). We compared Nutri-Pak (12-4-12 controlled release packet) and Harrell’s (12-4-12 controlled release polymer coated urea) against Atlantic (8-4-12 controlled release polymer coated urea, coated sulfate of potash), the most commonly used palm fertilizer in South Florida. Plants were grown in 25 cm (11 L) pots under 70% shade, watered weekly, with pest and weed control done as required. Plant growth parameters: number of leaves, leaf length …

Alteration Of Tobacco Alkaloid Content Through Modification Of Specific Cytochrome P450 Genes, Ralph E. Dewey, Balazs Siminszky, Steven W. Bowen, Lily Gavilano

Plant and Soil Sciences Faculty Patents

Compositions and methods for reducing the level of nomicotine and N'-nitrosonornicotine (NNN) in Nicotiana plants and plant parts thereof are provided. The compositions comprise isolated polynucleotides and polypeptides for cytochrome P450s that are involved in the metabolic conversion of nicotine to nornicotine in these plants. Expression cassettes, vectors, plants, and plant parts thereof comprising inhibitory sequences that target expression or function of the disclosed cytochrome P450 polypeptides are also provided. Methods for the use of these novel sequences to inhibit expression or function of cytochrome P450 polypeptides involved in this metabolic conversion are also provided. The methods find use in …

Residue Harvest Effects On Irrigated, No-Till Corn Yield And Nitrogen Response, Charles S. Wortmann, Charles A. Shapiro, Marty R. Schmer

Department of Agronomy and Horticulture: Faculty Publications

Crop residue harvest occurs on about 40% of Nebraska’s 3,700,000 ha of corn (Zea mays L.) land, primarily for feeding of beef cattle. Immobilization of applied N is expected to be less with residue harvest due to reduced microbial activity for digestion of high C/N ratio organic material. Residue reduction may affect subsequent crop yield and response to applied N. Field research was conducted at three locations over 2 yr in eastern Nebraska for irrigated, no-till corn following corn to determine residue harvest effects on yield and the economically optimal nitrogen rate (EONR). Study sites had deep silt loam …

Nebline, November/December 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: Chill Out Over the Holidays by Freezing Foods Ahead

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Forage News [2015-11], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

• Debby Dulworth as Keynote Speaker on Extending the Grazing Season at Heart of America Grazing Conference
• Study Shows No Damage to Soils from Grazing of Cover Crops
• Forage News Quote of the Month
• Get the Most out of Grazing Corn Stalks
• 2016 Kentucky Small Ruminant Grazing Conference schedule announced
• Muhlenberg County Producer and Ag Teacher to Represent Kentucky at AFGC
• Heart of America Grazing Conference Registration Open
• AGFC Annual Meeting Agenda Available

Pengaruh Dosis Pupuk Fosfor Dan Pupuk Organik Cair Terhadap Pertumbuhan Dan Hasil Kacang Hijau (Vigna Radiata L.) Pada Ultisol Jatinangor, Agus Wahyudin, Tati Nurmala, R. D. Rahmawati

Jurnal Kultivasi

Percobaan ini bertujuan untuk mengetahui pengaruh dosis pupuk fosfor dan pupuk organik cair terhadap pertumbuhan dan hasil tanaman kacang hijau (Vigna radiata L.). Percobaan dilaksanakan di kebun percobaan Fakultas Pertanian Universitas Padjadjaran, Jatinangor, Jawa Barat. Rancangan percobaan yang digunakan dalam penelitian ini adalah Rancangan Acak Kelompok (RAK) dengan sembilan perlakuan dan diulang tiga kali yaitu 50 kg ha-1 pupuk fosfor + O L ha-1 pupuk organik cair, 50 kg ha-1 pupuk fosfor + 4 L ha-1 pupuk organik cair, 50 kg ha-1 pupuk fosfor + 8 L ha-1 pupuk organik cair, 75 kg ha-1 pupuk fosfor + O L ha-1 …

Light Suppression Of Nitrate Reductase Activity In Seedling And Young Plant Tissues, Mark A. Schoenbeck, Bikash Shrestha, Melanie F. Mccormick, Timothy D. Kellner, Claudia M. Rauter

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Light is often reported to enhance plant nitrate reductase (NR) activity; we have identified a context in which light strongly suppresses NR activity. In vitro NR activity measurements of laboratory-grown seedlings showed strong suppression of nitrate-induced NR activity in cotyledon, hypocotyl, and root tissues of Ipomoea hederacea (L.) Jacquin; robust NR activity accumulated in nitrate-induced tissues in the dark, but was absent or significantly reduced in tissues exposed to light during the incubation. The suppressive mechanism appears to act at a point after nitrate perception; tissues pre-incubated with nitrate in the light were potentiated and developed NR activity more rapidly …

Traversing Swanton Road, 21st Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Nebline, October 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: We All Benefit From Pollinator Habitats

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Growing South Dakota (Fall 2015), College Of Agriculture &. Biological Sciences

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

[Page] 2 Internships Lead to Career Opportunities
[Page] 4 Pre-Professional Prep: Peer Mentors. Anatomy Lab, Networking Opportunities Provide Students Strong Start
[Page] 7 Difference Maker: Range Science Grad Strives To Inspire Native American Youth
[Page] 8 Profiles In Leadership: Preparing Students For A Lifetime Of Learning And Opportunities
[Page] 9 Investing In The Future: Scholarship Donors Share Commitment To Supporting Student Success
[Page] 10 College News
[Page] 12 Economic Buzz: Real-World Applications Gained Through New e-Trading Lab & Student Organizations
[Page] 14 Lessons In Leadership Student Organizations Help Hone Array Of Skills [Page] 15 Little I - 93 Years Of …

The Invasive American Weed Parthenium Hysterophorus Can Negatively Impact Malaria Control In Africa, Vincent O. Nyasembe, Xavier Cheseto, Fatma Kaplan, Woodbridge A. Foster, Peter E.A. Teal, James H. Tumlinson, Christian Borgemeister, Baldwyn Torto

All Peer-Reviewed Publications

The direct negative effects of invasive plant species on agriculture and biodiversity are well known, but their indirect effects on human health, and particularly their interactions with disease-transmitting vectors, remains poorly explored. This study sought to investigate the impact of the invasive Neotropical weed Parthenium hysterophorus and its toxins on the survival and energy reserves of the malaria vector Anopheles gambiae. In this study, we compared the fitness of An. gambiae fed on three differentially attractive mosquito host plants and their major toxins; the highly aggressive invasive Neotropical weed Parthenium hysterophorus (Asteraceae) in East Africa and two other adapted weeds, …

Lingnan Gardeners Newsletter (No. 10) = 嶺南彩園通訊 (第10期), Lingnan Gardeners, Kwan Fong Cultural Research And Development Programme, Lingnan University

Lingnan Gardeners Newsletter 嶺南彩園通訊

White Dews 白露

Nebline, September 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: 4-H Youth “Let the Good Times Grow” at Super Fair

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Summaries Of Arkansas Cotton Research 2014, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Bypassing Iron Storage In Endodermal Vacuoles Rescues The Iron Mobilization Defect In The Natural Resistance Associated-Macrophage Protein3natural Resistance Associated-Macrophage Protein4 Double Mutant, Viviane Mary, Magali Schnell Ramos, Cynthia Gillet, Amanda L. Socha, Jerome Giraudat, Astrid Agorio, Sylvain Merlot, Colin Clairet, Sun A. Kim, Tracy Punshon, Mary Lou Guerinot, Sebastien Thomine

Dartmouth Scholarship

To improve seed iron (Fe) content and bioavailability, it is crucial to decipher the mechanisms that control Fe storage during seed development. In Arabidopsis (Arabidopsis thaliana) seeds, most Fe is concentrated in insoluble precipitates, with phytate in the vacuoles of cells surrounding the vasculature of the embryo. NATURAL RESISTANCE ASSOCIATED-MACROPHAGE PROTEIN3 (AtNRAMP3) and AtNRAMP4 function redundantly in Fe retrieval from vacuoles during germination. When germinated under Fe-deficient conditions, development of the nramp3nramp4 double mutant is arrested as a consequence of impaired Fe mobilization. To identify novel genes involved in seed Fe homeostasis, we screened an …

Compositional Differences In Simulated Root Exudates Elicit A Limited Functional And Compositional Response In Soil Microbial Communities, Michael S. Strickland, Rebecca L. Mcculley, Jim A. Nelson, Mark A. Bradford

Plant and Soil Sciences Faculty Publications

Inputs of low molecular weight carbon (LMW-C) to soil - primarily via root exudates- are expected to be a major driver of microbial activity and source of stable soil organic carbon. It is expected that variation in the type and composition of LMW-C entering soil will influence microbial community composition and function. If this is the case then short-term changes in LMW-C inputs may alter processes regulated by these communities. To determine if change in the composition of LMW-C inputs influences microbial community function and composition, we conducted a 90 day microcosm experiment whereby soils sourced from three different land …