Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

PDF

2006

Plant Sciences

Masters Theses

Articles 1 - 8 of 8

Full-Text Articles in Entire DC Network

Horizontal Gene Transfer To Bacteria Of An Arabidopsis Thaliana Abc Transporter That Confers Kanamycin Resistance In Transgenic Plants, Kellie Parks Burris Dec 2006

Horizontal Gene Transfer To Bacteria Of An Arabidopsis Thaliana Abc Transporter That Confers Kanamycin Resistance In Transgenic Plants, Kellie Parks Burris

Masters Theses

The use of antibiotic resistance markers is an important tool in the production and selection of transgenic plants. There have been increased concerns about the potential horizontal gene transfer (HGT) from transgenic plants to bacteria of medical and environmental importance. Until recently all antibiotic resistance genes used in transgenic studies have been bacterial in origin. An Arabidopsis thaliana ABC transporter, Atwbc19, was the first plant gene shown to confer kanamycin resistance when overexpressed in transgenic plants. The Atwbc19 gene was evaluated for its ability to transfer antibiotic resistance to Escherichia coli, which are found in the human gut and environment ...


Established Predators Of Fiorinia Externa Ferris (Hemiptera: Diaspididae) On Eastern Hemlock (Tsuga Canadensis (L.) Carriere) In Urban And Forest Sites, Christine Ann Lynch Dec 2006

Established Predators Of Fiorinia Externa Ferris (Hemiptera: Diaspididae) On Eastern Hemlock (Tsuga Canadensis (L.) Carriere) In Urban And Forest Sites, Christine Ann Lynch

Masters Theses

A project was initiated in September 2004 to determine the indigenous predators of Fiorinia externa Ferris, the elongate hemlock scale (EHS), on eastern hemlock and their impact on the pest populations. Branch samples were taken monthly from four sites (two forest and two urban) in eastern Tennessee and western North Carolina to assess predator damage from October 2004 to April 2006. Predators of this exotic pest were collected from beat sheet samples from September 2004 to May 2006. Laboratory tests were conducted from field-collected predators to assess food consumption, feeding behavior, and intraguild competition among predators of EHS. From field ...


Probing Precursor Interactions With The Chloroplast Import Apparatus, Sarah Jean Wright Dec 2006

Probing Precursor Interactions With The Chloroplast Import Apparatus, Sarah Jean Wright

Masters Theses

The majority of plastid proteins are nuclear-encoded and imported post-translationally. A cleavable N-terminal extension, the transit peptide, targets these preproteins to the plastid. Transit peptides show very little primary sequence homology, yet are able to direct the precursor protein to interact with the protein components of the translocation complexes located within the inner and outer membranes of the chloroplast. In this study, a semi-conserved motif of the transit peptide, (F/W)(P/G)h(R/K) has been targeted for deletion in order to probe its importance. Two corresponding regions were deleted in the transit peptide of the precursor to ...


Expression Analysis Of Auxin Regulated Genes In Populus, Sara S. Jawdy Aug 2006

Expression Analysis Of Auxin Regulated Genes In Populus, Sara S. Jawdy

Masters Theses

Due to its many advantageous characteristics, such as a small sequenced genome, ease of vegetative propagation and availability of genomic tools and databases, Populus is widely becoming accepted as the model species among trees. In addition, DOE has chosen hybrid poplar as the model bioenergy feedstock tree. Due to the growing importance of the Populus species, genetic and genomic resources (EST and BLAST databases, genetic maps, etc.) are becoming increasingly available and are leading to a greater understanding of the functionality of the Populus genome. The goal of this study was to use these resources to further characterize the genetic ...


Determining Wear Tolerance Of Turfgrass Species For Athletic Fields In The Transition Zone, Jordan Rhea Goddard Aug 2006

Determining Wear Tolerance Of Turfgrass Species For Athletic Fields In The Transition Zone, Jordan Rhea Goddard

Masters Theses

A study to evaluate the performance of four different turfgrass varieties under simulated athletic field traffic in the transition zone was conducted in Tennesseeand Arkansas. ‘Thermal Blue’ hybrid bluegrass (Poa arachnifera Torr. x P. pratensis L.) has been introduced as a bluegrass variety bred for increased heat and drought tolerance. This variety provides a possible alternative to bermudagrass varieties in transition zone athletic fields. ‘Thermal Blue’ was compared to common bermudagrass (Cynodon dactylon L. Pers.) varieties ‘Riviera’ and ‘Quickstand’ and the hybrid bermudagrass (C. dactylon L. Pers. x C. transvaalensis Burt-Davy) variety ‘Tifway’. Each turfgrass species was tested with and ...


Risk Assessment Of Genetically Modified Crops By Direct Tracking Pollen Movement And Testing Crop Genetic Load Using Directly Transformed Brassica Rapa With Bt Cry1ac And Gfp Genes, Hong Seok Moon May 2006

Risk Assessment Of Genetically Modified Crops By Direct Tracking Pollen Movement And Testing Crop Genetic Load Using Directly Transformed Brassica Rapa With Bt Cry1ac And Gfp Genes, Hong Seok Moon

Masters Theses

One concern with crop biotechnology is that there might be crop to weed transgene flow, which could result in more invasive and competitive weed populations. Transgene expression, introgression of crop genes, and other ecological factors may alter the fitness or productivity of weed populations. The Brassica napus (crop) to Brassica rapa (weed) model to assess transgene flow and consequences has been widely used. In this study, weedy accessions of Brassica rapa were transformed with Bacillus thuringiensis (Bt) cry1Ac- and green fluorescence protein (GFP)- coding transgenes using Agrobacterium to develop plants to be subsequently used in risk assessment research. Regenerated transgenic ...


Mowing And Light-Weight Rolling Of Creeping Bentgrass (Agrostis Stolonifera L.) Putting Greens During Summer Heat Stress Periods In The Transition Zone, William Daniel Strunk May 2006

Mowing And Light-Weight Rolling Of Creeping Bentgrass (Agrostis Stolonifera L.) Putting Greens During Summer Heat Stress Periods In The Transition Zone, William Daniel Strunk

Masters Theses

A major challenge for golf course superintendents in the transition zone is to manage Agrostis stolonifera L. (creeping bentgrass) putting greens during heat stress periods of June, July, and August. In 2004 and 2005, a study was conducted to compare the effects of alternating rolling and mowing with traditional methods of everyday mowing on the green speed, turf quality, and disease occurrence creeping bentgrass putting greens in the transition zone. Treatments consisted of mowing six days week-1 without rolling, mowing six days week-1 with rolling three days week-1, and mowing three days week-1 alternating with rolling ...


Potassium And Cultivar Effects On Carbohydrate Partitioning In Upland Cotton, Jenny Dale Clement May 2006

Potassium And Cultivar Effects On Carbohydrate Partitioning In Upland Cotton, Jenny Dale Clement

Masters Theses

The indeterminate growth habit of upland cotton (Gossypium hirsutum L.) reduces the efficiency of yield formation when grown as an annual for its lint. Altering the determinacy may provide greater carbohydrate partitioning to reproductive structures, allowing higher yields. Another factor that may influence partitioning is potassium (K) nutrition. Potassium is essential for physiological and biochemical processes including translocation. It is necessary for ATP production, which is crucial for phloem loading and unloading. A three-year experiment was conducted at the West Tennessee Research and Education Center to evaluate carbohydrate partitioning in Paymaster 1218BG/RR (PM1218), a relatively determinate cultivar, and Deltapine ...