Contact

Phone: 470-578-6507

Email: dvogelie@kennesaw.edu

Office Location: SC 510

Office Hours:
by appointment

Student Directed Studies

Research Interests

  • Genetics and physiology of plant responses to environmental stressors (e.g. NaCl, water, heavy metals, organic pollutants, air pollutants, UV, etc.)
  • Development of laboratory exercises that use a current methodology/technique to study an interesting and relevant phenomenon or problem
  • Fingerprinting of daylily cultivars
  • In vitro propagation of plants by tissue culture

Student Directed Studies

  • Alicia Saran (Spring and Summer 2002 work currently in progress) - Selection of Cadmium Tolerant Mutants of C-Fern
  • Kathy Diehl (Summer and Fall 2001) SDS PAGE Analysis of Light Induced Proteins in Pea Seedlings: A Laboratory Exercise for Plant Physiology
  • Michelle Hall (2000 - 2001) Determination of Abscisic Acid Content in Water-Stressed Plants Using an Immunoassay: Development of a Laboratory Exercise for Plant Physiology
  • Dominika James and Jason Welch (2000) The Use of PCR to Generate Molecular Fingerprints of Daylily Cultivars
  • Marc Hogan (1998 - 1999) Cloning the Betty L. Siegel Daylily
  • Ken Rogers (1998) The Effects of Mechanical Pruning on Transpiration Rates in Boltonia asteroids Using a Sap-Flow Sensor
  • Andrew Norman (1997) Assessment of Differential Display PCR To Identify Biomarkers Produced in Response to Permethrin Stress by Coral Reefs

Alicia Saran - Selection of Cadmium Tolerant Mutants of C-Fern

Heavy metals are metals with an atomic number greater than 20 and include such elements as Zn, Cu, Cd, Hg, and Pb, among others. Although some heavy metals (e.g. Mn, Cu, Zn, Mo) are essential for many physiological processes in plants, these and other nonessential metals become stress factors when present at concentrations that exceed a certain threshold limit (Taiz and Zeiger, 1998; Orcutt and Nilsen, 2000). Large amounts of heavy metals have accumulated and continue to accumulate in the biosphere due to mining, manufacturing, agricultural and municipal waste disposal practices (Orcutt and Nilsen, 2000). Since heavy metals persist indefinitely, they are an increasing threat to plant and animal life. Information concerning heavy metal toxicity and homeostasis in plants is essential to address this problem. This directed study initiates a long-term project using the model plant systemCeratopteris richardii (also known as C-Fern) to study the various mechanisms associated with heavy metal toxicity and tolerance and identify the genes involved. In this pilot study, the effect of increasing levels of cadmium (Cd) on spore germination and gametophyte growth and development will be documented. A Cd concentration that is found to significantly inhibit spore germination will be used in a selection for putative mutants that possess increased tolerance to Cd. Such mutants are invaluable for future studies examining heavy metal stress and tolerance. The complexity of toxicity and tolerance responses are simplified by comparison of a sensitive wild type strain to a mutant strain (e.g. differing from the wild type by a single gene mutation) possessing enhanced tolerance. In addition, such mutants are the stock for identifying genes associated with sensitivity and enhanced tolerance. This work is supported by funds received from KSU College of Science and mathematics Mentor-Protg Program. (return to Student Directed Studies)

Kathy Diehl SDS PAGE Analysis of Light Induced Proteins in Pea Seedlings: A Laboratory Exercise for Plant Physiology (click for PDF format of lab exercise)

The Departments of Chemistry and Biological & Physical Sciences at KSU have undertaken a project to design laboratory exercises for a number of courses that will involve the use of one or more fundamental biochemical techniques (e.g.UV/VIS spectroscopy, protein electrophoresis and nucleic acid technology), the purpose of which is to demonstrate the wide application of these techniques to these two scientific fields. This directed study involved the development of an exercise for Plant Physiology Laboratory (BIOL 4420L) that would allow students to study chloroplast specific proteins. The light induced differentiation of etioplasts into chloroplasts and the light induced synthesis of a known chloroplast protein (Rubisco) provideed the basis for this study. Pea seedlings were grown in complete darkness and under a 12-hour photoperiod for 9 days, and shoot tissue from each set was extracted for protein. The concentration of protein in each sample was determined using Coomassie Blue Reagent and VIS spectroscopy. Aliquots of each sample containing the same amount of total protein were then subjected to sodium doedecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in order to separate the numerous proteins in each. Visual comparisons of the resulting protein profiles indicated several protein differences between light and dark grown tissues. Up-regulated, down-regulated and new proteins (9 total) were detected in the protein profile for light grown tissue. The large and small subunits of Rubisco were tentatively identified by molecular weight (55 kDa and 14 kDa, respectively) and comigration with a standard. The relative level of each subunit in dark and light grown samples was estimated directly from stained gels by using Strategene's ChemiDoc Image Analysis System (which employs VIS spectroscopy). Surprisingly, basal levels of both subunits were detected in dark grown tissues. The level of each subunit was approximately two-fold greater in light grown tissues. An additonal study exposed dark grown seedlings to 6, 18 and 24 hours of light in an attempt to document the timing required for induction of Rubisco synthesis. Preliminary results suggest that induction occurs between 18 and 24 hours of light exposure. This new exercise was piloted fall semester 2001 in BIOL 4420L. Class assessment (n = 12 students) indicated that the exercise was an interesting, challenging and valuable laboratory experience that furthered student understanding of key concepts in plant biology, strengthened basic laboratory skills, and provided specialized laboratory skills (e.g. SDS-PAGE). The exercise also received high marks for clarity (of instructions) and student success (83%). This work was supported by National Science Foundation DUE grant 9950288. (return to Student Directed Studies)

Michelle Hall Determination of Abscisic Acid Content in Water-Stressed Plants Using an Immunoassay: Development of a Laboratory Exercise for Plant Physiology (click for PDF format of exercise)

This directed study involved the development of a new laboratory exercise for a senior level plant physiology course. The role of plant hormones in growth and development is a major topic in plant physiology. Most published/available laboratory exercises dealing with plant hormones are designed to demonstrate an effect of a hormone(s) on a plant, plant part, or tissue (often observational in nature). Those that address detection and/or quantification of a hormone are dated in the methodology used (e.g. involve a bioassay) or require equipment and/or facilities not available at KSU. My directed study resulted in a laboratory exercise that involves the quantification of the hormone abscisic acid (ABA) in plant tissues using the newest method of hormone analysis an immunoassay. Following an established tissue extraction and sample purification procedure (Wang et al., 1994), students prepare extracts of 4 week old corn leaf tissue experiencing increasing levels of soil desiccation (0 7 days without water). The level of ABA in extracts is determined using a competitive ELISA (Enzyme-Linked Immunosorbent Assay). The immunoassay, available as a kit from Agdia (kit PDK 09347/0096), uses a monoclonal antibody specific for ABA and a competitive antibody binding method to measure concentrations of ABA in the plant extracts. Students measure the amount of competitive tracer (ABA-alkaline phosphatase conjugate) in antibody coated microwells by measuring A405using a microplate reader. They then calculate % binding for the standards and generate a standard curve using a Log-Logit data transformation (Logit% Binding vs. Log10 ABA Concentration). The amount of ABA in tissue samples is then determined. This exercise was piloted fall semester 2000 in BIOL 4420L. Class assessment (n = 13 students) indicated that the exercise was an interesting, challenging and valuable laboratory experience that furthered student understanding of key concepts in plant biology, strengthened basic laboratory skills, and provided specialized laboratory skills (e.g. immunoassay). The exercise also received high marks for clarity (of instructions). Student success rate was only 50% (probably due to micropipetting errors). This work was sponsored by National Science Foundation DUE grant 9950288. (return to Student Directed Studies)

Dominika James and Jason Welch The Use of PCR to Generate Molecular Fingerprints of Daylily Cultivars

Several thousand cultivars of daylilies are currently registered with the American Hemerocallis Society, with new cultivars added regularly.Currently, cultivars are identified by assessing an individual for defined morphological descriptors, such as flower color and size, foliage features, etc. Morphological characters, however, can often be influenced by growing conditions, plant health and plant age. Consequently morphological descriptors can be insufficient or unreliable for clear identification. This project initiated work to explore the potential use of a molecular technique, namely PCR, to generate a molecular fingerprint for a daylily cultivar that could be useful to distinguish it from other cultivars. We then proposed to use the fingerprints obtained for four daylily cultivars to develop a cultivar identification key. (return to Student Directed Studies)

Marc Hogan Cloning the Betty L. Siegel Daylily (KSU Symposium of Student Scholars poster abstract)

The Betty L. Siegel daylily was christened in 1997 by creator Ira Pegues, then a student at Kennesaw State University. In addition to sentimental value, this new hybrid has commercial value (e.g. KSU family and friends may be interested in the purchase of this daylily) and research value (e.g. cv. Betty L. Siegel daylily may be useful as parental material in future efforts designed to generate a daylily producing white flowers). Like any hybrid, the seed progeny from cv. Betty L. Siegel will not be true-to-type. Further, the plant may be infertile. Thus, propagation is limited to a natural asexual form of reproduction (e.g. duplication annually via tuberous roots). In June of 1998 efforts were begun to clone the Betty L. Siegel daylily using a method known as plant tissue culture. Plant tissue culture involves growing isolated plant cells, tissues, and/or organs in a "test tube" using a defined nutrient medium.This technique has the potential to ultimately result in rapid mass production of exact copies, or clones, of the original daylily. The undertaking of such a project often requires several years. We are pleased to announce that we have successfully produced over 60 putative clones of the Betty L. Siegel daylily during 1999. This poster leads the observer through the steps that led to the successful production of clones of the original Betty L. Siegel daylily. (return to Student directed Studies)

Ken Rogers The Effects of Mechanical Pruning on Transpiration Rates in Boltonia asteroids Using a Sap-Flow Sensor

This directed study examined the effect of mechanical damage via pruning on the transpiration rate of the perennial plant Boltinia asteroids(the star flower). Transpiration was monitored using the Flow2 Sap Flow System from Dynamax. This system uses on the heat balance method for monitoring transpiration rates whereby a heat source is applied to the stem surface, and sensors above, below, and at the point of stem heating measure heat dissipation via convection (e.g. sap flow). Mature vegetative plants (4) obtained from a local nursery were maintained in the laboratory close to a window. Temperature and irradiance (mmole/sec/m2) were continuously monitored using LiCor sensors and data logger. A well watered plant was found to have a transpiration rate directly related to the amount of sunlight available under constant temperature. Changes in irradiance due to change in cloud cover were followed by similar changes in transpiration rates. A fairly constant flow of 0.5 g H2O/hr was detected at night. Transpiration rates increased gradually during the AM hours as irradiance increased, peaked in mid-afternoon, and quickly dropped to basal level at dusk. Typical rates of 45 60 g/hr were detected during mid-day. On separate plants, 1, 2 and 3 lower branches were removed at mid-day, with no impact on sap flow rates detected. (return to Student Directed Studies)

Andrew Norman Assessment of Differential Display PCR To Identify Biomarkers Produced in Response to Permethrin Stress by Coral Reefs

This study was performed in collaboration with Georgia Institute of Technology (GIT). The investigation as a whole involves the use of a fairly new molecular technique, namely differential display PCR, to identify biomarkers produced by reef corals in response to various anthropogenic stressors. Collection of coral samples, exposure to stressors, isolation of total RNA, reverse transcription of mRNA, and differential display PCR were performed by Mike Morgan, graduate student at GIT. This directed study examined differential display PCR results for a single stressor, the insecticide permethrin. My role in this project, and the directed study completed, included the assessment of differential display results (autoradiograms) for the % of new, up-regulated and down- regulated transcripts/cDNAs, the selection and isolation of putatively differentially expressed cDNAs, and the completion of preliminary studies to test the authenticity of these differentially expressed/displayed cDNAs.

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