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A Comparison Of The Effects Of Burning, Haying And Mowing On Plants And Small Mammals In A Tallgrass Prairie Reconstruction, Ryan Allan Neuhaus

Dissertations and Theses @ UNI

Fire is an effective management tool for reconstructed prairies. However, due to safety concerns, road departments and other prairie managers are sometimes reluctant to use fire. Therefore, alternative techniques to manage reconstructed prairie, such as mowing or haying, need to be considered. The goal of this study is to determine if mowing and/or haying can be used to manage vegetation in lieu of fire for prairie reconstructions. This study examines the effects of four management techniques on plant and small mammal species in a tallgrass prairie reconstruction. No management, mowing, haying, and burning were replicated six times using a split …

Butterfly And Floral Community Dynamics At A Native Prairie Agrofuel Research Site, Benjamin J. Hoksch

Dissertations and Theses @ UNI

Agrofuel production in the Midwest has historically relied upon monoculture food crops (Zea mays and Glycine max) that do little to support biodiversity or maintain soil and water quality. The University of Northern Iowa’s Tallgrass Prairie Center is investigating the feasibility of establishing and harvesting diverse mixes of native prairie vegetation for use as a sustainable agrofuel. In 2009 48 research plots were established on three soil types, on land with a >30 year history of row crop production in Black Hawk County, IA. Each plot was seeded with one of four native prairie agrofuel crops: (1) Switchgrass1, (2) Grasses5 …

Analysis Of Plant Analytes Using Capillary Electrophoresis And High Performance Liquid Chromatography, Umme Kalsoom

Theses: Doctorates and Masters

Plants contain an enormous array of organic and inorganic components, the analysis for which may involve a wide range of methods. The focus of this study was to develop high performance liquid chromatography and capillary electrophoresis methods for the analysis of three classes of analytes: osmoregulants, minerals and amino acids.

Firstly, this study explored the potential of capillary electrophoresis for the analysis of three very common osmoregulants (proline, glycine betaine and mannitol). A diverse array of methods has been reported for determining each of these analytes, however, the literature on osmoregulants and their analysis is quite disjointed and traverses both …

Bioethanol: Feedstock Alternatives, Pretreatments,Lignin Chemistry, And The Potential For Green Value-Added Lignin Co-Products, Ruben Michael Ceballos, N. A. Batchenkova, M.K. Y. Chan, A. X. Duffing-Romero, A. E. Nelson, S. Man

Biological Sciences Faculty Publications and Presentations

Major challenges still exist in the cost-competitive production of cellulosic ethanol. Lignocellulose deconstruction using physiochemical pretreatments continues to be the most efficient way to remove lignin and expose cellulose for enzyme-mediated sugar reduction. Recent interest in the development of “value-added” lignin co-products and the desire to reduce the use of hazardous materials has prompted a resurgence of interest in alternative lignocellulosic feedstock and research into environment-friendly biological pretreatments. This article provides an overview of bioethanol processes and economics, standard and alternative feedstocks, physiochemical and biological pretreatments, and lignin chemistry. The chemistry and mode of action of ligninolytic and cellulolytic enzymes …

Study Of Factors Affecting Growth And Development Of Narrow Brown Leaf Spot Of Rice Caused By Cercospora Janseana (Racib.) O. Const., Kirandeep Kaur Mani

LSU Doctoral Dissertations

Studies evaluated the effects of planting date, cultivar susceptibility, fungicide application timing, nitrogen management, and tillage practices on the severity of narrow brown leaf spot of rice (NBLS) caused by Cercospora janseana. All factors evaluated affected NBLS severity. The mid-April planted rice had less NBLS as compared to mid-May, late planted rice. Propiconazole fungicide (Tilt) application at panicle initiation or early boot stage was found equally effective in terms of disease reduction in mid-April planting while panicle initiation stage was the best time to apply fungicide in the late planting (mid-May). Early onset and higher severity of NBLS was observed …

Rapid Root Elongation By Phreatophyte Seedlings Does Not Imply Tolerance Of Water Table Decline, Caroline A. Canham, Raymond H. Froend, William D. Stock

Research outputs 2014 to 2021

Key message Despite high rates of root elongation during phreatophyte establishment once connection to groundwater has occurred and leaf area develops, seedlings demonstrate limited capacity for root elongation in response to groundwater decline.

Abstract In a water-limited environment, rapid root elongation immediately after germination can be critical for a plant to reach deeper water sources such as a water table to avoid water deficit stress. However, once plants have accessed a water table, their continued survival may depend on their ability to adapt their root distribution to changes in the depth to a water table. In glasshouse experiments using two …

Using Plant Volatile Traps To Develop Phenology Models For Natural Enemies: An Example Using Chrysopa Nigricornis (Burmeister) (Neuroptera: Chrysopidae), Vincent P. Jones, David R. Horton, Nicholas J. Mills, Thomas R. Unruh, Eugene R. Milickzy, Peter W. Shearer, Kaushalya G. Amarasekare, Callie C. Baker, Tawnee D. Melton

Agricultural and Environmental Sciences Faculty Research

A model predicting phenology of adult Chrysopa nigricornis (Burmeister) (Neuroptera: Chrysopidae) in orchards was developed from field (trapping) data supplemented with development data collected under laboratory conditions. Lower and upper thresholds of 10.1°C and 29.9°C, respectively, were estimated from published and unpublished laboratory observations, and were used to develop a phenology model. Season-long field data were collected using white delta traps that had been baited with squalene, a volatile shown previously to be highly attractive to C. nigricornis. The model was developed from data collected in three Washington apple orchards, and was validated using independent data sets collected from apple, …

Interplanting Annual Ryegrass, Wheat, Oat, And Corn To Mitigate Iron Deficiency In Dry Beans, Emmanuel Chiwo Omondi, Andrew R. Kniss

Agricultural and Environmental Sciences Faculty Research

This study evaluated whether grass intercropping can be used to alleviate Fe deficiency chlorosis in dry beans (Phaseolus vulgaris L.) grown in high pH, calcareous soils with low organic matter. Field studies were conducted at the University of Wyoming Sustainable Agriculture Research and Extension Center in 2009 and 2010. Black- and navy beans were grown alone or intercropped with annual ryegrass (Lolium multiflorum Lam.), oat (Avena sativa L.), corn (Zea mays L.), or spring wheat (Triticum aestivum L.) in a two-factor factorial strip-plot randomized complete block design. All four grass species increased chlorophyll intensity in dry beans. However, grass species …

Linking Photosynthesis Physiology Of Upland Hardwood Reproduction To Ecology And Silviculture In The Arkansas Ozarks, Kutcher K. Cunningham

Theses and Dissertations

Oak (Quercus) forests in the Arkansas Ozarks have been important culturally, ecologically and environmentally for centuries. Historically these forests were fire dependent and dominated by oak species. In the past century, fire suppression and land management have caused these forests to densify. As a result, oaks are increasingly less abundant following disturbance in natural hardwood stands. Many applied ecological studies have explored methods and practices to maintain oak species in newly developing stands. This study attempted to link the mechanistic physiology of oak and non-oak reproduction to the applied ecological work. Varying stand conditions were generated in an undisturbed mature …

Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Managing Threats To The Urban Forest: From Dutch Elm Disease To Emerald Ash Borer - Learning From Experience, Christopher J. Borman

Doctor of Plant Health Program: Dissertations and Student Research

The urban forest provides important essential services to all municipalities; however, its value is often overlooked. The urban forest contributes to energy savings, environmental benefits, psychological well-being, and social benefits. Managing the urban forest in a sustainable manner is important if we wish to benefit from these services well into the future. Reliable management techniques have been created through previous experiences with pests, and these should be utilized and improved for use on urban forests.

American elm (Ulmus americana L.) was once a major component of the urban forests of North America. In 1927, Dutch elm disease (DED) was …

Soil Carbon And Nitrogen Mineralization And Crop Parameters In Typical Maize-Bean Intercropping In Western Kenya, Judith A. Odhiambo, Urszula Norton, Emmanuel C. Omondi, Dennis Ashilenje, Jay B. Norton

Agricultural and Environmental Sciences Faculty Research

Smallholder farmers in western Kenya who plant maize (Zea mays L.) intercropped with beans (Phaseolus vulgaris L.) face many challenges associated with nutrient-poor soils and weather-related crop failures. In regions where temperatures are favorable, crops are grown twice per year during long and short rainy seasons and in other regions, once per year during one long growing season. Growing crops two times per year necessitates frequent land preparation using inversion-type tillage. Little is known about the impact of current tillage-intensive crop management on annual soil organic matter (SOM) recovery. The aim of this study was to assess changes to soil …

Effect Of Temperature On The Phenology Of Chilo Partellus (Swinhoe) (Lepidoptera, Crambidae); Simulation And Visualization Of The Potential Future Distribution Of C. Partellus In Africa Under Warmer Temperatures Through The Development Of Life-Table Parameters, N. Khadioli, Z. E.H. Tonnang, E. Muchugu, G. Ong'amo, T. Achia, I. Kipchirchir, J. Kroschel, B. Le Ru

All Peer-Reviewed Publications

Maize (Zea mays) is a major staple food in Africa. However, maize production is severely reduced by damage caused by feeding lepidopteran pests. In East and Southern Africa, Chilo partellus is one of the most damaging cereal stem borers mainly found in the warmer lowland areas. In this study, it was hypothesized that the future distribution and abundance of C. partellus may be affected greatly by the current global warming. The temperature-dependent population growth potential of C. partellus was studied on artificial diet under laboratory conditions at six constant temperatures (15, 18, 20, 25, 28, 30, 32 and 35 °C), …

The Relationship Between Riparian Zone Width And Floristic Quality In Shenandoah County, Virginia, Jamie D. Smith

Masters Theses, 2010-2019

Riparian zones harbor an above average plant biodiversity. This biodiversity is threatened by invasive species and increasing human disturbance, the latter of which includes deforestation from agriculture and urban development. In this study, I examine relationship between the width of a forested riparian zone and the vegetation growing there. By using floristic quality assessment as a measure of anthropogenic disturbance, one can determine if wider riparian zones foster exclusion of non-native species while providing higher quality habitats for native plants. A randomized block design was used with three forested riparian treatments: deforested, moderately forested (woody vegetationstream), and extensively forested (woody …

Potential Effects Of Elevated Co2 On Pitcher Plant Nectar Composition, Prey Capture, And Inquiline Communities, Deirdre Courtney

Honors Theses

Human activities such as fossil fuel burning and deforestation have contributed significantly to the increasing levels of CO₂ in the atmosphere since the industrial revolution. Under the IPCC A1FI emission scenario, we are expected to reach levels as high as 1000 ppm by the end of the century. On average, C₃ plants experience a 27% increase in carbon to nitrogen (C:N) ratio under elevated CO₂. As a result, C₃ plants typically exhibit an increase in carbon-based secondary compounds. Carnivorous plants are a rare type of C₃ plant that has adapted to survive in low …

Transceptors At The Boundary Of Nutrient Transporters And Receptors: A New Role For Arabidopsis Sultr1;2 In Sulfur Sensing, Zheng Zhiliang, Bo Zheng, Thomsa Leustek

Publications and Research

Plants have evolved a sophisticated mechanism to sense the extracellular sulfur (S) status so that sulfate transport and S assimilation/metabolism can be coordinated. Genetic, biochemical, and molecular studies in Arabidopsis over the past 10 years have started to shed some light on the regulatory mechanism of the S response. Key advances in transcriptional regulation (SLIM1, MYB, and miR395), involvement of hormones (auxin, cytokinin, and abscisic acid) and identification of putative sensors (OASTL and SULTR1;2) are highlighted here. Although our current view of S nutrient sensing and signaling remains fragmented, it is anticipated that through further studies a sensing and signaling …

Mono- And Digalactosyldiacylglycerol Lipids Function Nonredundantly To Regulate Systemic Acquired Resistance In Plants, Qing-Ming Gao, Keshun Yu, Ye Xia, M. B. Shine, Caixia Wang, Duroy Navarre, Aardra Kachroo, Pradeep Kachroo

Plant Pathology Faculty Publications

The plant galactolipids monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) have been linked to the anti-inflammatory and cancer benefits of a green leafy vegetable diet in humans due to their ability to regulate the levels of free radicals like nitric oxide (NO). Here, we show that DGDG contributes to plant NO as well as salicylic acid biosynthesis and is required for the induction of systemic acquired resistance (SAR). In contrast, MGDG regulates the biosynthesis of the SAR signals azelaic acid (AzA) and glycerol-3-phosphate (G3P) that function downstream of NO. Interestingly, DGDG is also required for AzA-induced SAR, but MGDG is not. Notably, …

Pseudomonas Syringae Type Iii Effectors: Targets And Roles In Plant Immunity, Tania Y. Toruño

Center for Plant Science Innovation: Faculty Publications

Pseudomonas syringae is a Gram-negative bacterial pathogen that infects many crops. A central virulence strategy P. syringae uses to successfully infect plants is the injection of type III effector proteins (T3Es) into plant cells through a type IIII protein secretion system (T3SS). The T3SS is a molecular syringe found in many Gram-negative bacterial pathogens of plants and animals that transport T3Es from the bacterial cytosol into eukaryotic cells. T3Es disrupt host processes in the plant immune system required to restrict pathogen ingress. The plant innate immune system is divided in two branches, pathogen-associated molecular patterns (PAMP)-triggered immunity (PTI) and effector-triggered …

Metabolic Engineering Of Oilseed Crops To Produce High Levels Of Novel Acetyl Glyceride Oils With Reduced Viscosity, Freezing Point And Calorific Value, Jinjie Liu, Adam Rice, Kathleen Mcglew, Vincent Shaw, Hyunwoo Park, Thomas E. Clemente, Mike Pollard, John Ohlrogge, Timothy P. Durrett

Department of Agronomy and Horticulture: Faculty Publications

Seed oils have proved recalcitrant to modification for the production of industrially useful lipids. Here, we demonstrate the successful metabolic engineering and subsequent field production of an oilseed crop with the highest accumulation of unusual oil achieved so far in transgenic plants. Previously, expression of the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) gene in wild-type Arabidopsis seeds resulted in the accumulation of 45 mol% of unusual 3-acetyl-1,2- diacyl-sn-glycerols (acetyl-TAGs) in the seed oil (Durrett et al., 2010 PNAS 107:9464). Expression of EaDAcT in dgat1 mutants compromised in their ability to synthesize regular triacylglycerols increased acetyl-TAGs to 65 mol%. Camelina and soybean …

Using Avifauna To Access The Functional Success Of The Restored Beaver Creek Wetlands Near Cave Run Lake, Menifee County, Kentucky, Brian D. Wulker

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Brian D. Wulker on December 1, 2014.

Forest Farming Ramps, Jim Chamberlain, Dana Beegle, Katie Lajeunesse Connette

Agroforestry Notes (USDA-NAC)

The spring ephemeral, Allium tricoccum Ait. (called ramps in the south and wild leeks in more northern areas), is native to the forests of eastern North America. Ramps can be found growing in patches in rich, moist, deciduous forests in eastern North America. They begin to emerge when the soil temperatures increase after snow melt, which usually occurs in late March and early April, depending on geographic location. Young plants send up smooth, broad leaves that die back as the shrub and tree canopy closes, reducing the amount of sunlight that reaches the ramps. Patches of ramps often can be …

Characterization Of A Novel Fungal-Specific Gene, Fug1, In Fusarium Verticillioides, John Byron Ridenour

Graduate Theses and Dissertations

Filamentous fungi are responsible for numerous plant and animal diseases. The filamentous ascomycete Fusarium verticillioides is a globally important pathogen of maize, capable of causing severe yield reductions and economic losses. Also of substantial concern is the contamination of infected kernels with fumonisins, toxic secondary metabolites linked to toxicoses in humans and livestock. The number of sequenced fungal genomes is rapidly increasing. However, functional characterization of fungal genes has not progressed at a comparable rate. In pathogenic fungi, uncharacterized genes represent a source for novel virulence factors or anti-fungal targets. Therefore, to fully understand the genetic mechanisms underlying fungal pathogenesis, …

Identification Of Root-Knot Nematodes (Meloidogyne Spp.) Of Arkansas Using Molecular Diagnostics, Churamani Khanal

Graduate Theses and Dissertations

Root-knot nematodes (Meloidogyne spp.) are highly-adaptable, obligate plant parasites distributed worldwide. In addition, root-knot nematodes are an economically important genus of plant-parasitic nematodes. Meloidogyne incognita, M. arenaria, M. javanica, M. hapla and M. graminis have been reported from Arkansas during 1964 to 1994. Previous identifications were based primarily on morphological characters and host differentials. In this study, identification using molecular diagnostics methods was performed to identify Meloidogyne species present in Arkansas. A total of 106 soil and root samples from 36 of the 75 counties were collected and processed to obtain root-knot nematodes. Polymerase chain reaction (PCR) was performed …

Dissection Of Gray Leaf Spot Of Maize Through Functional Genomics, Robert Louis Hirsch

Graduate Theses and Dissertations

Gray leaf spot, caused by Cercospora zeae-maydis, is a devastating disease of maize that reduces yields and increases management costs. C. zeae-maydis penetrates maize leaves through stomata, but the biological and molecular bases of this process are poorly understood. The goal of this research was to elucidate the biological parameters of stomatal infection in C. zeae-maydis, and to identify and characterize novel genetic pathways involved in stomatal sensing and pathogenesis. Histopathological observations of a GFP-expressing strain of C. zeae-maydis during infection of maize indicated that the fungus responded to host-derived stomatal cues during the infection process. C. zeae-maydis was observed …

Evaluation Of Medicago Truncatula Accessions For Triterpene Saponins And Their Potential Impacts On Plant Pests, Samantha Roberson

Graduate Theses and Dissertations

Plants have developed numerous ways to protect themselves from microbes and insects, including producing secondary metabolites that negatively impact an invading pathogen or pest. Saponins are specialized metabolites found in many plant species and may play a role in protecting the plant. Though saponins are found in many plant species, triterpene saponins are found primarily in dicotyledons, including legumes. Medicago truncatula is a model system for studying legume biology and some accessions accumulate high concentrations of saponins. Accessions of M. truncatula known to have differing levels of saponins in both foliar and root tissues were tested for their suitability as …

First Report Of Goss's Bacterial Leaf Blight And Wilt Of Corn Caused By Clavibacter Michiganensis Subsp. Nebraskensis In North Dakota, A. Friskop, K. Kinzer, M. Mcconnell, Z. Liu, K. A. Korus, A. Timmerman, T. Jackson

Department of Plant Pathology: Faculty Publications

In August of 2011, the North Dakota State University Plant Diagnostic Lab received a hybrid corn (Zea mays) leaf sample from Burleigh County in southcentral North Dakota (ND). The leaf had long, irregular, water-soaked lesions consistent with Goss's leaf blight of corn. Using a light microscope at 10× magnification, bacterial streaming was observed from the excised edge of leaf tissue. A bacterial suspension was created, streaked onto a semi-selective CNS medium (1), and incubated at 22°C. Dark yellow-orange colonies appeared on the medium after 5 days. Single colonies were subcultured onto additional CNS media. To verify the identity …

The Effects Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Marie Allen

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Many row-crop fields today have declined in soil fertility due to poor management practices and overuse of pesticides. Under these conditions, plant nutrient uptake can be sub-optimal. There are several soil amendments that can be used to improve soil quality and plant growth such as traditional fertilizers and manure applications. This study focused on the addition of biochar to the soil and the use of structured water to enhance plant growth. Biochar is a nutrient rich product that is produced by pyrolysis of organic feedstocks and contains high rates of carbon. Previous studies which focused on biochar have shown an …

Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs

Graduate Theses and Dissertations

Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …

Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford

Graduate Theses and Dissertations

Several potential indicators of rice (Oryza sativa L.) response to nitrogen (N) fertilization include the soils alkaline hydrolyzableN (AHN) concentration, seeding date, and the soils clayfixed NH₄N content. Three studies were conducted to: (1) correlate AHN, determined using Illinois Soil Nitrogen Test (ISNT) or Nitrogen Soil Test for Rice (NSTaR), to plant parameters of interest and develop a fertilizer N rate calibration curve capable of predicting the 95% relative grain yield (RGY) fertilizer N rate for rice grown on clayey soils; (2) evaluate the influence of seeding date and N fertilization on rice plant growth and grain …

The Effect Of Agricultural Practices On Sugar Beet Root Aphid (Pemphigus Betae Doane) And Beneficial Epigeal Arthropods, Rudolph J. Pretorius

Department of Entomology: Dissertations, Theses, and Student Research

This study investigated the effect of several agricultural practices on the sugar beet root aphid (Pemphigus betae Doane) and beneficial epigeal natural enemies in western Nebraska sugar beet agroecosystems. Eight glyphosate-tolerant sugar beet varieties were evaluated under field conditions for their resistance to root aphids. High levels of aphid resistance were detected for some varieties. In conjunction to this, pitfall sampling was conducted to determine the beneficial epigeal natural enemy complex in the area, which could contribute to the management of both root aphids and glyphosate-resistant weeds. Ground beetles comprised an important and abundant component of this fauna, with …