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Barrow Island Ute Guide - Non-Indigenous Invertebrates, Frogs, Reptiles & Weeds, Mike Grimm, Kristofer Collett, Jessica Harrison, Peter Davis, Marc Widmer, Andras Szito, Rob Emery, Peter Mangano, John Botha, David Robinson, Brad Maryan Jan 2013

Barrow Island Ute Guide - Non-Indigenous Invertebrates, Frogs, Reptiles & Weeds, Mike Grimm, Kristofer Collett, Jessica Harrison, Peter Davis, Marc Widmer, Andras Szito, Rob Emery, Peter Mangano, John Botha, David Robinson, Brad Maryan

Biosecurity published reports

Barrow Island, the second largest island in Western Australia, is a Class A Nature Reserve and home to a variety of rare and endangered fauna and flora, some of which occur nowhere else. To protect fauna and flora it is essential workers and visitors to the island are aware of the risks that a non-indigenous species (NIS) poses to the ecological balance of Barrow Island.

Workers and visitors to Barrow Island need to be aware and keep their eyes open for any unusual fauna and flora that might be in accommodation units, recreation areas or the work place. Reports from …


A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen Jan 2013

A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen

LSU Master's Theses

There are more than 7800 species of Pucciniales (rust fungi) described. Aeciospores and urediniospores of rust fungi are a food source for the larval stage of members of the fly genus Mycodiplosis, hence these could be of interest as potential biological control agents. Currently, Mycodiplosis contains 49 described species based on adult male morphology. A survey of 1,350 rust-infected plants from 44 countries was recently conducted to assess the occurrence of Mycodiplosis fly larvae across a broad spectrum of Pucciniales. Larvae were found on 261 collections from 25 countries. Statistical analyses explored the distribution of larvae in relation to host …


Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva Jan 2013

Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva

LSU Master's Theses

Sweetpotato production in the southern United States is being threatened by a soft rot that develops in storage roots when fields are flooded and by an important post-harvest disease caused mainly by the fungi Fusarium solani and Macrophomina phaseolina. To identify the pathogens responsible for development of the soft rot, samples were collected from storage roots with soft rot from intentionally flooded fields and decayed tissue was streaked on plates of nutrient dextrose agar plus 0.05% cysteine and incubated anaerobically. Two distinct groups of Gram positive strict anaerobic bacteria were re-isolated from rotting storage roots. Endospores were observed in all …


Mitigating Predatory Ants Promotes Establishment Of Biological Control Of Arundo By Arundo Scale In The Cattle Fever Tick Quarantine Zone, A. Velez-Bonner, W. L. A. Osbrink, D. W. Thomas, Kenneth R. Summy, A. T. Showler, A. Perez De Leon, John A. Goolsby Jan 2013

Mitigating Predatory Ants Promotes Establishment Of Biological Control Of Arundo By Arundo Scale In The Cattle Fever Tick Quarantine Zone, A. Velez-Bonner, W. L. A. Osbrink, D. W. Thomas, Kenneth R. Summy, A. T. Showler, A. Perez De Leon, John A. Goolsby

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

Ant collection, identification, and control experiments were conducted to improve the establishment of the arundo scale, Rhizaspidiotus donacis, a biological control agent of Arundo donax, an invasive weed in the riparian habitats along the Rio Grande in Texas. Observational studies indicated R. donacis immatures are preyed upon by a variety of predator insects, especially ants. A survey of the principle ant species was made at sites along the Rio Grande with Arundo donax to help direct biological control strategies. We conclude that uses of ant baits can effectively control the common ant species found in these habitats and improve the …


A Genetic Study On The Virulence Mechanism Of Burkholderia Glumae And, Rice Resistance To Bacterial Panicle Blight And Sheath Blight, Hari Sharan Karki Jan 2013

A Genetic Study On The Virulence Mechanism Of Burkholderia Glumae And, Rice Resistance To Bacterial Panicle Blight And Sheath Blight, Hari Sharan Karki

LSU Doctoral Dissertations

Burkholderia glumae is a rice pathogenic bacterium that causes bacterial panicle blight. Some strains of this pathogen produce dark brown pigments when grown on the casamino-acid peptone glucose (CPG) agar medium. A pigment-positive and highly virulent strain of B. glumae, 411gr-6, was randomly mutagenized with mini-Tn5gus, and the resulting mini-Tn5gus derivatives showing altered pigmentation phenotypes were screened on CPG agar plates to identify the genetic elements governing the pigmentation of B. glumae. In this study, several positive and negative regulators, for the pigmentation of B. glumae were identified. During this study, a novel two-component regulatory system (TCRS) composed of the …


Verticordia Micropropagation Through Direct Ex Vitro Rooting, Belinda Delaney Jan 2013

Verticordia Micropropagation Through Direct Ex Vitro Rooting, Belinda Delaney

Theses: Doctorates and Masters

The objective of this study was to improve the existing shoot multiplication protocol for Verticordia grandis (McComb, Arthur & Newll, 1986; Newell, Growns & McComb, 2005) and to investigate and establish reliable root induction and acclimatisation protocols to enhance survival of micropropagated plantlets. It was envisaged that these protocols would be successful in micropropagation, growth and survival of different V. grandis clones and possibly applicable to other Verticordia species.


The elongation of in vitro Verticordia shoots on multiplication media was improved by reducing the concentration of BAP from 1μM to 0.25 μM, which resulted in a more uniform shoot length …


Bmp Planning To Address Urban Runoff: Plaster Creek Watershed Sustain Pilot, Tetra Tech, Inc. Dec 2012

Bmp Planning To Address Urban Runoff: Plaster Creek Watershed Sustain Pilot, Tetra Tech, Inc.

Watershed Reports

The Plaster Creek watershed is tributary to the Grand River in west Michigan. Plaster Creek is one of several impaired streams in this area, located in metropolitan Grand Rapids. There are several listed impairments for the Creek including 1) other indigenous aquatic life and wildlife, 2) warm water fishery, and 3) total and partial body contact recreation. Total maximum daily load (TMDL) studies were completed in 2002 for biota and E. coli to address the listed impairments. In 2008, a watershed management plan (WMP) was developed which outlines an implementation plan for water quality improvement in the watershed. This pilot …


Characterization Of Chemotype And Aggressiveness Of Nebraska Isolates Of Fusarium Graminearum, Anita Panthi Dec 2012

Characterization Of Chemotype And Aggressiveness Of Nebraska Isolates Of Fusarium Graminearum, Anita Panthi

Department of Agricultural Leadership, Education, and Communication: Dissertations, Theses, and Student Research

Fusarium head blight (FHB), caused mainly by Fusarium graminearum, is a devastating disease of wheat and other small grain cereals. FHB lowers grain yield and quality and contaminates grain with mycotoxins, predominantly deoxynivalenol (DON) and its acetylated derivatives 3-ADON and 15-ADON. Forty one Fusarium isolates collected from grain elevators and wheat fields in Nebraska in 2009 and 2010 were sequenced for molecular identification. Forty isolates were identified as F. graminearum and one isolate was identified as F. culmorum. Seventy seven F. graminearum isolates collected from grain elevators and wheat fields in Nebraska from 2007 to 2010 were tested …


Major Fusarium Diseases On Corn, Wheat, And Soybeans In Nebraska, Bo Liu, Loren J. Giesler, Tamra A. Jackson-Ziems, Stephen N. Wegulo, Robert M. Harveson, Kevin A. Korus, Robert N. Klein Dec 2012

Major Fusarium Diseases On Corn, Wheat, And Soybeans In Nebraska, Bo Liu, Loren J. Giesler, Tamra A. Jackson-Ziems, Stephen N. Wegulo, Robert M. Harveson, Kevin A. Korus, Robert N. Klein

Department of Plant Pathology: Faculty Publications

Fusarium species are associated with diseases of corn, wheat, and soybean, causing significant yield loss in Nebraska. Some produce mycotoxins that are harmful to humans and animals.


Updated Manuscript Submission Guidelines For The Prairie Naturalist, Christopher N. Jacques, Troy W. Grovenburg, Jonathan A. Jenks Dec 2012

Updated Manuscript Submission Guidelines For The Prairie Naturalist, Christopher N. Jacques, Troy W. Grovenburg, Jonathan A. Jenks

The Prairie Naturalist

These guidelines present updated policies and procedures for submitting scientific manuscripts for consideration for publication in The Prairie Naturalist (PNAT). These guidelines incorporate substantial changes that have occurred following a change in Editorial staff during January 2009, and update the online “Suggestions for Contributors” guidelines provided on the PNAT website (http://www.sdstate.edu/nrm/organizations/gpnss/tpn/index.cfm); these instructions supersede all previous guidelines.

Tables and appendices are included for common word expressions with superfluous wording (Table 1), examples of correct format and style guidelines for tables accompanying manuscripts (Table 2, Appendix A), guidance in properly preparing Research notes (Appendix B) and citing literature (Appendix …


Terrestrial And Semi-Aquatic Vertebrates In Diets Of Largemouth Bass In Central Nebraska, Seth A. Lundgren, Keith Geluso, Casey W. Schoenebeck Dec 2012

Terrestrial And Semi-Aquatic Vertebrates In Diets Of Largemouth Bass In Central Nebraska, Seth A. Lundgren, Keith Geluso, Casey W. Schoenebeck

The Prairie Naturalist

Largemouth bass (Micropterus salmoides) are opportunistic predators often feeding in littoral areas during crepuscular periods (Snow 1971). Adult largemouth bass primarily are piscivorous, whereas juveniles generally consume zooplankton, insects, and small fish (Zweiacker and Summerfelt 1974, Carlander 1977, Post 2003). Age-0 largemouth bass generally consume zooplankton and macroinvertebrates (Keast and Webb 1966, Keast 1985, Phillips et al. 1995, Post 2003) and shift to piscivory at 50-70 mm in length (Phillips et al. 1995, Olson 1996, Post 2003). Few studies have documented detailed accounts of other vertebrates besides fish in diets of largemouth bass, which include amphibians (Hodgson and …


Plant Community Composition And Structure Monitoring For Scotts Bluff National Monument, 2012 Annual Report, Isabel W. Ashton, Michael Prowatzke, Stephen K. Wilson Dec 2012

Plant Community Composition And Structure Monitoring For Scotts Bluff National Monument, 2012 Annual Report, Isabel W. Ashton, Michael Prowatzke, Stephen K. Wilson

United States National Park Service: Publications

Executive Summary

the last remnants of native mixed-grass prairie in the region. The Northern Great Plains Inventory & Monitoring Network (NGPN) surveyed 8 long-term monitoring plots in Scotts Bluff National Monument in 2012 as part of an effort to better understand the condition of plant communities in the park. We measured plant diversity and cover, estimated tree and shrub density, looked for the presence of exotic species that are of concern to park management, and evaluated the amount of human and natural disturbance at all plots. This effort was the second year in a multiple-year venture to document the current …


Southeast South Dakota Experiment Farm Annual Progress Report, 2012, Agricultural Experiment Station Dec 2012

Southeast South Dakota Experiment Farm Annual Progress Report, 2012, Agricultural Experiment Station

Agricultural Experiment Station and Research Farm Annual Reports

This document highlights 23 crop and livestock research and demonstration reports from projects conducted at Southeast Research Farm in 2012. It is published by the South Dakota Agricultural Experiment Station and Cooperative Extension Service at South Dakota State University in cooperation with the Southeast South Dakota Experiment Farm Corporation. Reports in this document include information on: weather and climate data, corn production and performance, soybean research and planting, soil testing, alfalfa yield test, fertilizer testing, herbicide research, crop rotation, sorghum, small grains, swine research, and pest and weed control.


False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen Dec 2012

False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen

Graduate Theses and Dissertations

False smut of rice, caused by Ustilaginoidea virens (Cooke) Takahashi (Teleomorph: Villosiclava virens), has become a common disease in most major rice growing regions throughout the world. Considerable confusion exists regarding the infection process and the disease cycle. Therefore, a clearer understanding of pathogenesis caused by Ustilaginoidea virens is critical for future efforts to develop genetic and chemical tools to manage false smut in Arkansas and other regions of the world. The overall goal of this research was to clarify the infection process underlying false smut, with emphasis on comparing and contrasting the histological basis of root and foliar infections. …


Environmental Triggers Of Winter Annual Weed Emergence And Management To Reduce Soybean Cyst Nematode Reproduction On Winter Annual Weed Hosts, Rodrigo Werle Dec 2012

Environmental Triggers Of Winter Annual Weed Emergence And Management To Reduce Soybean Cyst Nematode Reproduction On Winter Annual Weed Hosts, Rodrigo Werle

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

Winter annual weeds are becoming more common in many row crop fields in the midwestern USA. The impact of winter annual weeds in cropping systems is often overlooked because these weeds complete their lifecycle near the time of crop sowing. However, delayed soil warming, competition for nutrients during initial establishment of the main crop, difficult planting operations, and yield loss are some of the problems caused by dense mats of winter annual weeds. Moreover, some of these weeds have been reported as alternative hosts for pests such as the soybean cyst nematode (Heterodera glycines, SCN), considered the most …


The Biological Control Of Spotted Knapweed In The Southeastern United States, Carey R. Minteer Dec 2012

The Biological Control Of Spotted Knapweed In The Southeastern United States, Carey R. Minteer

Graduate Theses and Dissertations

Spotted knapweed is an invasive, short-term-perennial plant that is native to Eurasia. It was accidentally introduced into North America in the early 1890's and has since spread across The United States and Canada. Spotted knapweed degrades rangelands and pastures by negatively impacting native plants, increasing soil surface runoff and stream sediment yields, and reducing soil infiltration. A biological control program for spotted knapweed using Larinus minutus (Coleoptera: Curculionidae), was initiated in Arkansas in 2008. In this dissertation I described the releases of L. minutus and investigated the adult activity in the southeastern United States (Chapter 1), investigated the effects of …


Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller Dec 2012

Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller

Graduate Theses and Dissertations

Sirex (Hymenoptera: Siricidae) woodwasps develop within xylem of host conifers. Sirex females drill through the bark, phloem and into xylem tissues where they deposit eggs along with a symbiotic Amylostereum fungus. The presence of Amylostereum is necessary for successful development of Sirex immatures as the larvae are unable to derive adequate nutrition from xylem in the absence of the fungus. The Eurasian woodwasp, Sirex noctilio F., was discovered in northeastern North America in 2004. Sirex noctilio has caused significant economic damage in Pinus radiata D. Don plantations of the southern hemisphere, but is of little economic significance in its native …


Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher Dec 2012

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …


A Review Of Cover Crops For Eastern Nebraska, Tyler Williams Dec 2012

A Review Of Cover Crops For Eastern Nebraska, Tyler Williams

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

The focus of this project is two fold, first to provide a short literature review of cover crops (CC) and then discuss the results from a field experiment that was designed to evaluate the nitrogen contribution from cover crop mixes to the subsequent corn crop. The literature review will focus on the aspects of CC that are related to the field of study. Cover crops, as defined by the United States Department of Agriculture (USDA) are crops that are agronomically sound and grown for the purpose of erosion control or other objectives related to conservation or soil improvement. Cover crops …


Nitrous Oxide Emissions From Smooth Bromegrass Pasture Under Nitrogen Fertilizer And Ruminant Urine Application In Eastern Nebraska, Laura K. Snell Dec 2012

Nitrous Oxide Emissions From Smooth Bromegrass Pasture Under Nitrogen Fertilizer And Ruminant Urine Application In Eastern Nebraska, Laura K. Snell

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

Nitrous oxide (N2O) is a greenhouse gas primarily produced in soils by denitrifying and nitrifying organisms. Agricultural soils account for 70% of emissions in the United States, but little data is available for contributions from managed pasture ecosystems. This study focused on the production of N2O in smooth bromegrass (Bromus inermis Leyss.) pastures established on silt loam soils in eastern Nebraska. Thirty smooth bromegrass plots (1.5m x 1.5m) were treated with five different fertilizer treatments (0, 45, 90, 135, and 180 kg N/ha) and two urine treatments (urine and no urine). Herbage sampling was taken …


Ecology And Invasive Properties Of Musk Thistle (Carduus Nutans) In The Central Prairies Of Nebraska, Chengchou Han Dec 2012

Ecology And Invasive Properties Of Musk Thistle (Carduus Nutans) In The Central Prairies Of Nebraska, Chengchou Han

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

Musk thistle (Carduus nutans) is an herbaceous monocarpic herb introduced to the U. S. from Eurasia. The invasion of musk thistle can reduce forage area, soil stability, and reduce recreation and open areas for humans and wildlife.

Resistance of warm season and cool season perennial grass communities to musk thistle invasion is important for land managers to consider, especially where disturbance has made an area particularly susceptible. Our results show that disturbances, such as overgrazing can open up niches in canopies of warm season grass communities and facilitate invasion but not in cool season grass communities. The mechanism …


Characterisation Of Pharmaceutical Grade Horse Chestnut Waste, Joanna Przyborska Dec 2012

Characterisation Of Pharmaceutical Grade Horse Chestnut Waste, Joanna Przyborska

Theses

Horse chestnut residue was made available by a local pharmaceutical company. The residue was subjected to compositional analysis and studied to determine potential for residual biological activity, including prebiotic, antimicrobial, anti-hyaluronidase and anti-elastase effects.

The residue had 52 % total solids, including 2.97% ash, 6.93% protein, 1.89% crude fat. Oleic acid (74.7%) was the main fatty acid components in the crude lipid component. The major ash components were potassium, phosphorus, calcium and magnesium.

Prebiotic potential of aqueous extract (HCE) from horse chestnut residue was confirmed. A new formula for calculation of prebiotic index (PI) was developed. PI for probiotics (Lactobacillus …


Avian Diversity And Habitat Use On Wetland Reserve Program Lands In The Lower Missouri River Valley, Eric C. Hopps Dec 2012

Avian Diversity And Habitat Use On Wetland Reserve Program Lands In The Lower Missouri River Valley, Eric C. Hopps

The Prairie Naturalist

A primary objective of the Wetland Reserve Program (WRP) is to provide habitat for migratory birds throughout all seasons of the year. Comprehensive avian assessments are lacking and limit our ability to evaluate the benefits of the WRP to continental bird populations. I investigated avian species occurrence on WRP lands within the Lower Missouri River Valley (LMRV), Nebraska, USA, from March 2010 to February 2011. Ten WRP habitat types are described based on plant community assemblages and observed hydrological regimes. Estimates of avian species richness were greatest in lowland forest (n = 115), lowland woodland (n = 83) and upland …


Fish Assemblage Structure In Black Hills, South Dakota Streams, Luke D. Schultz, Sarah J. Lewis, Katie Nicole Bertrand Dec 2012

Fish Assemblage Structure In Black Hills, South Dakota Streams, Luke D. Schultz, Sarah J. Lewis, Katie Nicole Bertrand

The Prairie Naturalist

Understanding factors structuring fish assemblages in a particular area is valuable to both sport fishery management and native species conservation. Fish assemblages in the Black Hills are unique to South Dakota because they contain economically valuable introduced salmonids as well as native species of conservation need. Our objective was to examine the relationship between fish assemblages and geomorphic and reach-scale habitat features across multiple stream reaches in the Black Hills. Canonical correspondence analysis, a direct gradient ordination analysis, indicated that factors operating at multiple spatial scales interacted to structure fish assemblages. There also was indication of segregation between native species …


Walleye Trophic Position Before And After A Gizzard Shad Extirpation, Bethany J. Bethke, Justin A. Vandehey, Mark J. Fincel, Brian D.S. Graeb, Mark T. Porath Dec 2012

Walleye Trophic Position Before And After A Gizzard Shad Extirpation, Bethany J. Bethke, Justin A. Vandehey, Mark J. Fincel, Brian D.S. Graeb, Mark T. Porath

The Prairie Naturalist

Walleye (Sander vitreus) are an ecologically and recreationally important sport fish species. Reduced growth and condition in walleye can occur when prey availability is limited. In two Nebraska reservoirs, walleye consumed gizzard shad (Dorosoma cepedianum) as their primary prey until a winterkill extirpated the gizzard shad in 2001. Because of the winterkill, walleye in the two reservoirs had to change to alternative prey items. Our objective was to determine if stable isotope analysis on archived walleye scales can be used to detect a known food web shift in two reservoir food webs. We quantified the changes …


Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou Dec 2012

Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou

Graduate Theses and Dissertations

Soybean vein necrosis disease (SVND) is widespread in major soybean-producing areas in the U.S. The typical disease symptoms exhibit as vein clearing along the main vein, which turn into chlorosis or necrosis as season progresses. Double-stranded RNA isolation and shot gun cloning of symptomatic tissues revealed the presence of a new tospovirus, provisionally named as Soybean vein necrosis associated virus (SVNaV). The presence of the virus has been confirmed in 12 states: Arkansas, Illinois, Missouri, Kansas, Tennessee, Kentucky, Mississippi, Maryland, Delaware, Virginia and New York. Symptomatic samples collected from eight states (AR, IL, MO, MS, KS, TN, MD and DE), …


Taxonomy And Dna Barcoding In The Genus Manfreda (Salisb.) Asparagaceae, William David Ritchie Dec 2012

Taxonomy And Dna Barcoding In The Genus Manfreda (Salisb.) Asparagaceae, William David Ritchie

Graduate Theses and Dissertations

The genus Manfreda Salisb. of Asparagaceae is a genus of potential horticultural interest and is currently subject to breeding efforts at the University of Arkansas. A lack of taxonomic clarity however undermines the classification of potential inter - and intrageneric hybrids. The study aims to assess existing species delimitation within the genus Manfreda employing morphology while investigating the potential utility of Consortium for the Barcode of Life Plant (CBOL) DNA Barcodes for identification of specific taxa and an External Transcribed Spacer (ETS) - Internal Transcribed Spacer (ITS) DNA barcode for developed hybridized taxa.

Observation of 855 herbarium specimens facilitated phylogenetic …


Evaluation Of The Recombination Efficiencies Of Flp Proteins, Linh Duy Nguyen Dec 2012

Evaluation Of The Recombination Efficiencies Of Flp Proteins, Linh Duy Nguyen

Graduate Theses and Dissertations

Site-specific recombination systems are powerful tools for genetic modification. They have been used to integrate a transgene into a pre-defined locus and to remove marker genes from a transgene locus. Two of the most widely used site-specific recombination systems in plants are the Cre/lox system from the bacteriophage P1 and the FLP/FRT system from the yeast Saccharomyces cerevisiae. The Cre/lox system is well-characterized and is the first choice in application of site-specific recombination system. However, some applications such as marker-free site-specific gene integration require the use of two recombination systems. In addition, the availability of alternative recombination systems can offer …


Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga Dec 2012

Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga

Graduate Theses and Dissertations

Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …


Breeding For Modified Seed Composition In Soybean: Selection Of Genotypes, Yield Stability, And Environmental Effects, Luciano Miguel Jaureguy Dec 2012

Breeding For Modified Seed Composition In Soybean: Selection Of Genotypes, Yield Stability, And Environmental Effects, Luciano Miguel Jaureguy

Graduate Theses and Dissertations

The development of cultivars with modified seed composition represents an excellent alternative to cope with the world's need for more nutritious food. Understanding the genetic and environmental factors controlling crop seed quality traits is of crucial importance for such an endeavor. The objectives of this study were: a) to evaluate the efficiency of phenotype and marker-assisted selection for low stachyose and low phytate soybean breeding lines, and their yield stability, b) to study the effect of management practices planting date and delayed harvest on soybean seed composition, and c) to study the potential association between soil properties and leaf chemical …