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Decomposition And Nutrient Release Of Different Cover Crops In Organic Farm Systems, Jianru Shi

School of Natural Resources: Dissertations, Theses, and Student Research

Cover crops act as green manure adding organic matter to agricultural-soils. For legume green manures to be an effective nitrogen (N) source for organic farming systems, their N release must be in synchrony with crop N demand. The objectives of this study were 1) determine the decomposition rates of three common cover crops (white clover, (Trifolium repens,L ) red clover (Trifolium pratense L.) and soybean (Glycine max L) in order to determine when most N was released and its synchrony with subsequent corn crop uptake; 2) we focused on the effect of cover crops on soil …

Functional Annotation, Transcriptional Characterization And Enzymatic Contributions Of Essential Amino Acid Biosynthesis-Related Genes, Teresa J. Clark

Masters Theses

In plants, essential amino acid biosynthesis predominantly or exclusively occurs in the plastid. The plastid in the heterokont alga Nannochloropsis oceanica is surrounded by four membranes, which add great complexity to intracellular trafficking and communication. N. oceanica genes in essential amino acid biosynthesis were functionally annotated. The biosynthesis pathways resemble the pathways in Arabidopsis thaliana, but the gene content seems to be simpler in N. oceanica.

In addition, two A. thaliana mutants with loss-of-function mutations in the aspartate kinase-homoserine dehydrogenase 2 (AK-HSDH2) gene were characterized. These ak-hsdh2 mutants demonstrate unexpected accumulation of aspartate-derived amino acids (ADAAs), particularly threonine, in …

Distribution Of Burrowing Owls In East- Central South Dakota, Jiill A. Shaffer, Jason P. Thiele

The Prairie Naturalist

Western burrowing owl (Athene cunicularia hypugaea) populations have declined across much of western North America, particularly at the northern and eastern edges of the species’ breeding range (Martell et al. 2001, Murphy et al. 2001, Shyry et al. 2001, Skeel et al. 2001, Klute et al. 2003). In South Dakota, the burrowing owl is a summer resident that historically was relatively common throughout the state, but its range has decreased in recent decades, especially in the eastern half of the state (Whitney et al. 1978, South Dakota Ornithologists’ Union [SDOU] 1991, Peterson 1995). Tallman et al. (2002) described the species …

Notes: Nesting Patterns Of Red-Tailed Hawks And Great-Horned Owls In South-Cen- Tral Kansas, William Langley

The Prairie Naturalist

Red-tailed hawks (Buteo jamaicensis) and great-horned owls (Bubo virginianus) can influence the nesting behavior of each other through direct competition for nesting sites. For instance, owls begin nesting before hawks and, thus, can use nests from the previous year and prevent hawks from occupying those sites (Orians and Kuhl- man 1956, Gilmer et al. 1983, Minor et al. 1993). However, both species sometimes kill the nestlings of the other (Craig- head and Craighead 1956, Bosakowski et al. 1989).

The objective of my study was to investigate nesting patterns of these two raptors at the edge of the tallgrass prairie over …

Research Notes Vs. Research Articles, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! I hope this email finds you well, winding down another academic year, and looking forward to the summer field season. Warm temperatures, peak foliage, and heightened anticipation of the start of another field season are upon us following a long winter season and unusually wet spring for many of us across the Great Plains. Here in westcentral Illinois, wild turkeys are gobbling, neotropical migrants are singing and establishing breeding territories, and white-tailed deer are within days of giving birth to the next generation of fawns. Granted, there are many outdoor activities to participate in, though oppressive heat …

Necrotic Ring Spot And Summer Patch Of Turfgrass, Claudia Nischwitz, Kelly Kopp, Jaydee Gunnell, Kent Evans, Erin Frank

All Current Publications

No abstract provided.

Cytochrome P450s And Uses Thereof, Joe Chappell, Lyle F. Ralston

Plant and Soil Sciences Faculty Patents

The invention features isolated cytochrome P450 polypeptides and nucleic acid molecules, as well as expression vectors and transgenic plants containing these molecules. In addition, the invention features uses of such molecules in methods of increasing the level of resistance against a disease caused by a plant pathogen in a transgenic plant, in methods for producing altered compounds, for example, hydroxylated compounds, and in methods of producing isoprenoid compounds.

A Literature Review Of The Health Effects Of A Plant Based Diet Versus An Animal Based Diet, James Cote

Senior Honors Theses

Health and nutrition can mean a myriad of things to many people in today’s culture. The majority of the time people are unaware of the proper nutrients their body needs and how to get them from food. This thesis will seek to expose the health benefits that are associated with consuming a raw plant-based die, offering a more profound and encompassing view on nutrition. Investigating further into today’s most common diseases such as diabetes, heart disease, obesity, cancer and autoimmune disorders, it will seek to discover and answer why we have so many health issues. This thesis will discuss the …

Discovery Of Bald Cypress Fossil Leaves At The Gray Fossil Site, Tennessee And Their Ecological Significance., Sara Brandon

Undergraduate Honors Theses

This study focuses on fossil Taxodium leaves found at the Gray Fossil Site in northeastern Tennessee where many 7-4.5 million year old plants and animals have been recovered. Identification of the leaves is based on comparison of leaf morphology and confirmed by leaf anatomy. The ecological implications of the fossil are discussed to understand the paleoecology and paleoclimate at the Gray site. It is concluded that the fossil plant along with many other plants lived by a large sinkhole lake under a little warmer-than-today’s climate condition.

High Occurrence Of Functional New Chimeric Genes In Survey Of Rice Chromosome 3 Short Arm Genome Sequences, Chengjun Zhang, Jun Wang, Nicholas C. Marowsky, Manyuan Long, Rod A. Wing, Chuanzhu Fan

Biological Sciences Faculty Research Publications

In an effort to identify newly evolved genes in rice,we searched the genomes of Asian-cultivated rice Oryza sativa ssp. japonica and its wild progenitors, looking for lineage-specific genes. Using genome pairwise comparison of approximately 20-Mb DNA sequences from the chromosome 3 short arm (Chr3s) in six rice species, O. sativa, O. nivara, O. rufipogon, O. glaberrima, O. barthii, and O. punctata, combined with synonymous substitution rate tests and other evidence, we were able to identify potential recently duplicated genes, which evolved within the last 1 Myr. We identified 28 functional O. sativa genes, which …

Occurrence Of Meloidogyne Fallax In North America, And Molecular Characterization Of M. Fallax And M. Minor From U.S. Golf Course Greens, Claudia Nischwitz

All Current Publications

No abstract provided.

Application Carrier Volume: A Comprehensive Evaluation Of An Ultra-Low Volume Sprayer Compared To A Conventional Sprayer For Row-Crop And Turfgrass Production Systems, Jason Connor Ferguson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

An Ultra-Low Volume (ULV) sprayer was developed to decrease carrier volume required for pesticide applications in row and turfgrass cropping systems. The ULV sprayer can make spray applications at or below 19 L ha^-1, which is far lower than a conventional sprayer in row crop or turfgrass production systems. Field studies were conducted at the University of Nebraska West Central Research and Extension Center Dryland Farm near North Platte, NE and the John Seaton Anderson Turfgrass Research Facility near Mead, NE to compare the ULV sprayer to a conventional sprayer. Studies were conducted to compare the two sprayers …

Metabolic Engineering Of Flavonoid Biosynthesis In Scutellaria Lateriflora Hairy Roots By Ectopic Expression Of The Atmyb12 Transcription Factor, Tianhong Yang

Student Theses and Dissertations

American skullcap (Scutellaria lateriflora), a perennial herb native to America, is rich in specialized metabolites that have shown various biological activities. In particular, the flavonoids wogonin, baicalein and baicalin have proven anticancer properties in vitro. However, the regulatory mechanisms and biosynthetic steps leading to these specialized metabolites have not been elucidated. To address this issue, hairy root cultures of S. lateriflora expressing the flavonoid-specific transcription factor AtMYB12 from Arabidopsis thaliana were developed using Agrobacterium rhizogenes ATCC 15834 containing a binary vector harboring the AtMYB12 cDNA under the control of the SuperP:TEV expression system. In this study, three AtMYB12 transgenic hairy …

Eastern Kentucky Farmer's Willingness To Grow Biomass For Emergy Production, Austin P. Jacobs

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 by Austin P. Jacobs in May of 2013.

Drought Stress Acclimation Imparts Tolerance To Sclerotinia Sclerotiorum And Pseudomonas Syringae In Nicotiana Benthamiana, Venkategowda Ramegowda, Muthappa Senthil-Kumar, Yasuhiro Ishiga, Amita Kaundal, Makarla Udayakumar, Kirankumar S. Mysore

Plants, Soils, and Climate Faculty Publications

Acclimation of plants with an abiotic stress can impart tolerance to some biotic stresses. Such a priming response has not been widely studied. In particular, little is known about enhanced defense capacity of drought stress acclimated plants to fungal and bacterial pathogens. Here we show that prior drought acclimation in Nicotiana benthamiana plants imparts tolerance to necrotrophic fungus, Sclerotinia sclerotiorum, and also to hemi-biotrophic bacterial pathogen, Pseudomonas syringae pv. tabaci. S. sclerotiorum inoculation on N. benthamiana plants acclimated with drought stress lead to less disease-induced cell death compared to non-acclimated plants. Furthermore, inoculation of P. syringae pv. tabaci on N. …

Agricultural Research Magazine, May-June 2013

Agricultural Research Magazine

Table of Contents

4 Olives! Scientists Take a New Look at an Ancient Crop

8 Getting Hooked on Farmed Salmon: A Good Source of Omega-3s

10 Nematode-Filled Capsules Tested Against Corn Rootworms

12 Viral Infection in Sheep Linked to Gene

14 Cited for More Than 60 Years of Flavor Research

17 Dogs, Pine Trees, and Carbs: Studies Lead to New Pet- Food Ingredient

18 Nourishing America’s Preemies: Scientists Confront the Challenges of IV Feeding

20 Mapping the Way to Even Healthier Rice

22 New Bioenergy Yeast Is an Overachiever

23 Locations Featured in This Magazine Issue

Nematode-Filled Capsules Tested Against Corn Rootworms, Jan Suszkiw

Agricultural Research Magazine

Each spring, the western corn rootworm (Diabrotica virgifera) awakens from its winter slumber to wreak havoc on corn crops across the United States. The pest emerges in larval form, hatching from small white eggs deposited beneath the soil and causing significant feeding damage to the grain crop’s roots. The toll on U.S. farmers: an estimated $1-2 billion annually in yield losses and chemical control.

European growers face a similar threat from the pest, which was first reported in a corn field near the Belgrade international airport in Serbia (formerly Yugoslavia) in 1992, but is presumed to have arrived …

Landscape Features Impact On Soil Available Water, Corn Biomass, And Gene Expression During The Late Vegetative Stage, Stephanie Hansen, Sharon A. Clay, David E. Clay, C. Gregg Carlson, Graig Reicks, Youssef Jarachi, David Horvath

Agronomy, Horticulture and Plant Science Faculty Publications

Crop yields at summit positions of rolling landscapes often are lower than backslope yields. The differences in plant response may be the result of many different factors. We examined corn (Zea mays L.) plant productivity, gene expression, soil water, and nutrient availability in two landscape positions located in historically high (backslope) and moderate (summit and shoulder) yielding zones to gain insight into plant response differences. Growth characteristics, gene expression, and soil parameters (water and N and P content) were determined at the V12 growth stage of corn. At tassel, plant biomass, N content, ¹³C isotope discrimination (Δ), and …

Influence Of Transplanter Modification And Previous Crop On The Production Of No-Till Dark Tobacco, William Frazier Penick

Masters Theses & Specialist Projects

Dark tobacco (Nicotiana tabacum L.) has historically been produced using
conventional tillage practices. Soil is cultivated multiple times throughout a growing season leading to an increased incidence of soil erosion. No-till systems have been growing in popularity with the advent of new technology that has enabled the practice to be performed effectively and efficiently. With the recent expansion of no-till practices throughout the agricultural community, many crops have had success in producing comparable yields while reducing input costs and saving soil resources. For this experiment, a traditional tobacco transplanter was modified for use in a no-till environment. All modifications were …

Patatin-Related Phospholipase Pplaiiiδ Increases Seed Oil Content With Long-Chain Fatty Acids In Arabidopsis, Maoyin Li, Sung Bahn, Chuchuan Fan, Jia Li, Tien Phan, Michael Ortiz, Mary Roth, Ruth Welti, Jan Jaworski, Xuemin Wang

Biology Department Faculty Works

The release of fatty acids from membrane lipids has been implicated in various metabolic and physiological processes, but in many cases, the enzymes involved and their functions in plants remain unclear. Patatin-related phospholipase As (pPLAs) constitute a major family of acyl-hydrolyzing enzymes in plants. Here, we show that pPLAIIId promotes the production of triacylglycerols with 20- and 22-carbon fatty acids in Arabidopsis (Arabidopsis thaliana). Of the four pPLAIIIs (a, b, g, d), only pPLAIIId gene knockout results in a decrease in seed oil content, and pPLAIIId is most highly expressed in developing embryos. The overexpression of pPLAIIId increases the content …

Biodiesel Transesterification Byproducts As Soil Amendments, Solomon Parker

Graduate Theses and Dissertations

For every ten kilograms of biodiesel that is produced from the transesterification of vegetable oil, approximately 1 kg of glycerol is produced as a byproduct. Also known as glycerin, it is a chemical used in many products including cosmetics, foods, and desiccants. However, the crude glycerol created during biodiesel production is tainted with potassium hydroxide and methanol making it unsuitable for commercial use without costly refinement. With increase in production of biodiesel driven by rising fuel prices, the market has become glutted with glycerol and it is on the threshold of becoming a waste product. Common methods for disposing glycerol …

Using The Ceres-Maize Model To Create A Geographically Explicit Grid Based Estimate Of Corn Yield Under Climate Change Scenarios, Ryan Zachary Johnston

Graduate Theses and Dissertations

The CERES-Maize model was evaluated in its capacity to predict both regional maize yield and water use within the United States Department of Agriculture (USDA) Economic Research Service (ERS) Region 1 between the years 1997-2007. A grid based, geospatially explicit method was developed to express the various rainfed and irrigated maize cultivars grown across the region. Overall, the calibrated model compared well for both physiological and yield parameters, producing significant linear relationships (p

The calibrated and validated CERES-Maize model was used to predict potential evapotranspiration and yield under three IPCC weather scenarios for the year 2050 to evaluate crop production …

Initial Fine Mapping Of The Spinach Downy Mildew Resistance Locus Rpf1, Wei Yang

Graduate Theses and Dissertations

Spinach is an important vegetable crop grown in many parts of the world (Correll et al. 2011). It has become increasingly popular due to its nutritional value as it is very high in antioxidants (Prior, 2003). Spinach production, however, is affected by many biotic stresses. Downy mildew, caused by Peronospora farinosa f. sp. spinaciae (Pfs) , is perhaps the most important biotic constraint for spinach production worldwide (Correll et al, 1994). As of 2012, 14 races of Pfs have been reported (Correll et al., 2011). The rapid increase of new races is likely a direct result of substantial changes in …

Morphological And Molecular Taxonomic Identification And Phylogenetics Of Criconematoidea, Marco Cordero

Graduate Theses and Dissertations

The superfamily Criconematoidea has been studied since 1886. It is composed of two families: Criconematidae (subfam. Criconematinae, Hemicycliophorinae) and Tylenchulidae (subfam. Tylenchulinae, Paratylenchinae and Tylenchocriconematinae). Multiple species in genera have been identified and differences and similarities have been found. Species belonging to genera Mesocriconema and Criconemoides show very few differences making their identification difficult. Seventy two populations were studied. They were collected in Arkansas and/or received from the following states: California, Florida, Kansas, Missouri, North Carolina and Tennessee. Populations of the following species were identified: Mesocriconema curvatum, M. kirjanovae, M. onoense, M. ornatum, M. sphaerocephala, M. surinamense, M. vadense, M. …

Evaluation Of Wetland Plants For Susceptibility To Species Of Phytophthora Present In Runoff Water At Ornamental Plant Nurseries, Garrett Ridge

All Theses

Competition between agricultural producers and urban communities for high quality water is increasing; therefore, growers need to adopt water conservation and reuse practices to ensure an adequate supply of irrigation water. One concern with recycled irrigation water is the potential to recirculate propagules of oomycete pathogens. Constructed wetlands are a biologically-based treatment option for nutrient and chemical remediation that potentially also could filter pathogen propagules. The goal of this study was to assess the susceptibility of plants routinely used in constructed wetlands to infection by species of Phytophthora commonly found at ornamental plant nurseries. In laboratory and greenhouse experiments, an …

Final Evaluation Of The North East Agricultural Region (Near) Strategy, Andrew Blake, Don Burnside, Vicki Williams

All other publications

No abstract provided.

Physiological Effects Of Low Mowing Heights, Rolling, And Foot Traffic On Creeping Bentgrass Putting Greens, Joseph Ronald Young

Graduate Theses and Dissertations

Golf course superintendents are managing creeping bentgrass (Agrostis stolonifera L.) putting greens throughout the transition zone where temperatures can exceed optimum levels for consecutive days in the summer. The stress of creeping bentgrass associated with these supraoptimal temperatures has been well documented, but the management practices implemented on putting greens to increase green speeds may exacerbate these environmental stresses. To date, the physiological effects of these management practices in combination have not been evaluated for putting green turf. The objective of this dissertation project was to determine the effect of mowing heights, light-weight rolling, and foot traffic on performance and …

Uromyces Appendiculatus In Honduras: Pathogen Diversity And Host Resistance Screening, Maricelis Acevedo, James R. Steadman, Juan C. Rosas

Department of Plant Pathology: Faculty Publications

Bean rust, caused by the fungus Uromyces appendiculatus, is a major constraint for common bean production worldwide. Virulence of U. appendiculatus collected from wild and cultivated Phaseolus spp. was examined in 28 locations across Honduras. Host accessions representing wild and domesticated Phaseolus spp. collected at the same sampling locations were evaluated for resistance against U. appendiculatus. In total, 91 pathotypes were identified from 385 U. appendiculatus isolates according to their virulence on each of the 12 host differentials. No significant difference in pathogen total virulence, measured as the mean disease score, was found between locations. However, significant differences …

Section Abstracts: Botany

Virginia Journal of Science

Abstracts of the Botany Section for the 91st Annual Virginia Journal of Science Meeting, May 2013

Puccinia Mariae-Wilsoniae And Claytonia Virginica: A Pathogen's Tale, Sarah A. Schlund

Undergraduate Honors Theses

Rusts are economically important fungal plant pathogens. For the majority of rust species, complete life history data, including host range, geographic distribution, plant response to the rust, identity of alternate hosts, and mode of sexual reproduction are incomplete. The purpose of this study was to examine the life history of Puccinia mariae-wilsoniae, a rust on Claytonia virginica (spring beauty), and to observe responses in leaf anatomy to its fungal pathogen. Spring beauty is an ephemeral woodland plant that lasts three to four weeks and P. mariae-wilsoniae infects C. virginica almost as soon as the plant emerges from dormancy in …