Daniel J. Arp
Botany and Plant Pathology
(541) 737-1294, arpd@science.oregonstate.edu
Microbial N cycle, biological nitrogen fixation, nitrification, bioremediation, microbial biochemistry

Anita N. Azarenko
Horticulture
(541) 737-5457, azarenka@science.oregonstate.edu
Hormonal regulation of plant growth and development

Barbara J. Bond
Forest Science
(541) 737-6110, Barbara.Bond@orst.edu
Physiological processes on the whole-plant and community scale; light distribution, photosynthesis, foliar chemistry, drought tolerance

Patrick J. Breen
Horticulture
(541) 737-5469, breenp@science.oregonstate.edu

Michael J. Burke
Horticulture
(541) 737-2211, mike.burke@orst.edu
Plant stress physiology; frost survival of plants, ice nucleation active bacteria

Paul M. Chen
Horticulture
(541) 386-2030, paul.chen@orst.edu
Post harvest physiology of pome fruits

Tony H. H. Chen
Horticulture
(541) 737-5444, chent@science.oregonstate.edu
Stress physiology; molecular basis of plant adaptation to freezing and desiccation stress

Larry S. Daley
Horticulture
(541) 737-2657, daleyl@science.oregonstate.edu
Physiological and biochemical characterization of plant germplasm

Paul S. Doescher
Rangeland Resources
(541) 737-1622, Paul.S.Doescher@orst.edu
Physiological processes and ecophysiological dynamics in rangeland ecosystems

Robert P. Doss
Horticulture
(541) 750-8773, dossr@science.oregonstate.edu
Physiology of flowering; plant-disease and plant-insect interactions

Leslie H. Fuchigami
Horticulture
(541) 737-5445, fuchigal@science.oregonstate.edu
Regulation of dormancy; stress physiology of woody plants

Barbara L. Gartner
Forest Products
(541) 737-4213, barbara.gartner@orst.edu
Physiological and structural aspects of the xylem; wood anatomy and quality; physiological ecology

David B. Hannaway
Crop and Soil Science
(541) 737-5863, david.hannaway@orst.edu
Crop physiology and expert system development for alfalfa

Terri L. Lomax
Botany and Plant Pathology
(541) 737-5278, lomaxt@science.oregonstate.edu
Molecular biology of plant growth and development; cellular signal transduction chains; auxin physiology and transport

Richard F. Miller
Rangeland Resources
(541) 573-2064, richard.miller@orst.edu
Processes and mechanism of plant competition and succession in rangelands

Machteld C. Mok
Horticulture
(541) 737-5456, mokm@science.oregonstate.edu
Genetic regulation of cytokinin metabolism; genetic improvement of plants using tissue culture techniques

David D. Myrold
Crop and Soil Science
(541) 737-5737, david.myrold@orst.edu
Forest soils and soil microbilogy

William M. Proebsting
Horticulture
(541) 737-5454, proebstw@science.oregonstate.edu
Physiological genetics; genetic and photoperiodic regulation of gibberellin metabolism

Steven R. Radosevich
Forest Science
(541) 737-6081, Steve.Radosevich@orst.edu
Physiological ecology; physiological basis for plant-plant interference; mechanism of herbicide resistance

Timothy L. Righetti
Horticulture
(541) 737-5466, righettt@science.oregonstate.edu
Mineral uptake, transport, and partitioning in woody plants

Bernadine C. Strik
Horticulture
(541) 737-5434, strikb@science.oregonstate.edu
Production physiology in small fruits and viticulture

David T. Tingey
Botany and Plant Pathology
(541) 754-4621, dtingey@mail.cor.epa.gov
Environmental stress physiology; effects of environmental of air pollutants

Nan C. Vance
Forest Science
(541) 750-7302, nan.vance@orst.edu
Stress physiology of forest species; genetics of taxane production; reintroduction of native plants at high elevations

Patricia A. Wheeler
Oceanography
(541) 737-0558, pwheeler@ocas.oregonstate.edu
Nitrogen metabolism in marine phytoplankton, macroalgae, and bacteria

William E. Winner
Botany and Plant Pathology
(541) 737-1749, winnerw@science.oregonstate.edu
Stress physiology; plant responses to multiple stresses

Ronald E. Wrolstad
Food Science and Technology
(541) 737-3591, ron.wrolsta@orst.edu
Chemical composition of fruits and vegetables; changes in composition with processing and storage

Donald B. Zobel
Botany and Plant Pathology
(541) 737-5280, zobeld@science.oregonstate.edu
Autecology of forest species

Mailing addresses of units with faculty in the Plant Physiology Program:

Department of Botany and Plant Pathology
Oregon State University
2082 Cordley Hall
Corvallis, OR 97331-2902

Department of Crop and Soil Science
Oregon State University
Crop Science 109B
Corvallis, OR 97331-3002

Department of Horticulture
Oregon State University
Ag. and Life Sciences 4017
Corvallis, OR 97331-7304

Department of Forest Products
Oregon State University
Richardson Hall 119
Corvallis, OR 97331-5751

Department of Forest Science
Oregon State University
Richardson Hall 321
Corvallis, OR 97331-5752

College of Oceanic and Atmospheric Sciences
Oregon State University
104 Oeanography Administration Buld.
Corvallis, OR 97331-5503

Department of Rangeland Resources
Oregon State University
202 Strand Agricultural Hall
Corvallis, OR 97331-6704

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Donald J. Armstrong

Date and Place of Degree: 1967, University of Wisconsin
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Hormonal regulation of plant growth and development; metabolism and mechanism of action in cytokinins

Description of Research:

Identification and characterization of the regulatory mechanisms and molecular sites controlling cytokinin metabolism and function are the primary objectives of this research program. Current investigations are focused on the regulation of cytokinin metabolism in tissue culture systems derived from various genotypes of Phaseolus (bean), with particular emphasis on the regulatory mechanisms controlling the production and activity of the enzyme cytokinin oxidase. Cytokinin oxidase is widely distributed in plant tissues and plays an important role in the control of cytokinin levels by catalyzing the oxidative degradation of cytokinins bearing unsaturated isoprenoid side chains. Specific problems under investigation include:
1. The physical, catalytic, and regulatory properties of cytokinin oxidase from Phaseolus callus tissues
2. The molecular basis of regulatory mechanisms controlling the levels of cytokinin oxidase activity in Phaseolus callus tissues
3. The biochemical basis of genetically determined variations in the rates of cytokinin degradation in Phaseolus callus tissues
4. Developmental regulation of cytokinin oxidase activity in Phaseolus

RELATED PUBLICATIONS:

Chatfield, J. M. and D. J. Armstrong. 1986. Regulation of cytokinin oxidase activity in callus tissues of Phaseolus vulgaris L. cv. Great Northern. Plant Physiol. 80:493-499.

Chatfield, J. M. and D. J. Armstrong. 1987. Cytokinin oxidase from Phaseolus vulgaris callus tissues. Enhanced in vitro activity of the enzyme in the presence of copper-imidazole complexes. Plant Physiol. 84:726-731.

Chatfield, J. M. and D. J. Armstrong. 1988. Cytokinin oxidase from Phaseolus vulgaris callus cultures: Affinity for concanavalin A. Plant Physiol. 88:245-247.

Armstrong, D. J. and R. A. Firtel. 1989. Cytokinin oxidase activity in the cellular slime mold Dictyostelium discoideum. Dev. Biology 136:491-499.

Kaminek, M. and D. J. Armstrong. 1990. Genotypic variation in cytokinin oxidase from Phaseolus callus culture. Plant Physiol. 93:1530-1535.

Abdelnour-Esquivel, A., M. Kaminek, and D. J. Armstrong. 1992. Inhibition of dopamine-ß-hydroxylase by cytokinins. J. Plant Growth Reg. 11:221-226.

Armstrong, D. J. 1994. Cytokinin oxidase and the regulation of cytokinin degradation. In: Cytokinins--chemistry, activity, and function. D. W. S. Mok and M. Mok, eds. CRC Press. pp. 139-154.

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Daniel J. Arp

Date and Place of Degree: 1980, University of Wisconsin
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Microbial N cycle, biological nitrogen fixation, nitrification, bioremediation, microbial biochemistry

DESCRIPTION OF RESEARCH:

The enzymes involved in the transformations of N-containing compounds in the N cycle are under investigation. One research project is focused on hydrogenase, the Ni and Fe containing enzyme which recycles the H2 produced by nitrogenase. Another project deals with ammonia monooxygenase, the enzyme that initiates the process of nitrification. Biological nitrification results in a loss to leaching and volatilization of fertilizer nitrogen applied to croplands. Because of the broad substrate range of ammonia monooxygenase, we are also investigating bioremediation of environmental pollutants.

RELATED PUBLICATIONS:

Ensign, S. A., M. R. Hyman, and D. J. Arp. 1993. In vitro activation of ammonia monooxygenase from Nitrosomonas europaea by copper. J. Bacteriol. 175:1971-1980.

Sayavedra-Soto, L. A. and D. J. Arp. 1993. In hydrogenase from Azotobacter vinelandii, substitution of the Cys 62, 65, 289, 292 for Ser in the small (HoxK) subunit affects H2 oxidation. J. Bacteriol. 175:3414-3421.

Juliette, L., M. R. Hyman, and D. J. Arp. 1993. Mechanism-based inactivation of ammonia mono-oxygenase in Nitrosomonas europaea by allylsulfide. Appl. Environ. Microbiol. 59:3728-3735.

Sayavedra-Soto, L., N. G. Hommes, and D. J. Arp. 1994. Characterization of the gene encoding hydroxylamine oxidoreductase in Nitrosomonas europaea. J. Bacteriol. 176:504-510.

Hommes, N. G., L. A. Sayavedra-Soto, and D. J. Arp. DNA sequence of hcy, a gene encoding cytochrome c-554 from Nitrosomonas europaea. Gene (in press).

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Anita N. Azarenko

Date and Place of Degree: 1987, University of Maryland
Rank and Department: Associate Professor, Horticulture

RESEARCH AREA: Tree fruit and hazelnut physiology; flower development; pollen-stigma interactions; metabolism in dormant Prunus persica flower buds and seed; vir gene induction in Pseudomonas syringae by bark constituents of Prunus avium

DESCRIPTION OF RESEARCH:

The major research focus is on identifying and studying physiological, environmental, and genetic factors involved in the floral biology of deciduous tree fruit and nuts. Research on pollen-stigma interactions in Corylus avellana (hazelnut) is being directed towards understanding the mechanism of sporophytic self-incompatibility (SSI). Associated with this is determining the similarity of Corylus sp. SSI with that of Brassica sp. SSI and t he identification and purification of s-allele specific glycoproteins from the stigma and pollen. Respiratory metabolism and its role in flower bud and seed dormancy is also being studied using a highly sensitive technology, differential scanning calorimetry, and other biochemical and molecular tools.

RELATED PUBLICATIONS:

Hampson, C. R., A. N. Azarenko, and A. Soeldner. 1994. Pollen-stigma interactions following compatible and incompatible pollinations in hazelnut. J. Amer. Soc. Hort. Sci. 118:814-819.

Hampson, C. R. and A. N. Azarenko. 1994. Hybridization of the Brassica self-incompatibility gene with hazelnut. HortScience 29:462 (Abstr.).

Gardea, A. A., Y. M. Moreno, A. N. Azarenko, P. B. Lombard, L. S. Daley, and R. S. Criddle. 1994. Changes in metabolic properties of grape buds during development. J. Amer. Soc. Hort. Sci. 119:756-760.

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Barbara J. Bond

Date and Place of Degree: 1992, Oregon State University
Rank and Department: Assistant Professor, Forest Science

RESEARCH AREA: Physiological processes on the whole-plant and community scale; light distribution, photosynthesis, foliar chemistry, drought tolerance

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Patrick J. Breen

Date and Place of Degree: 1967, University of Minnesota
Rank and Department: Professor, Horticulture

RESEARCH AREA: Phloem transport and fruit physiology

DESCRIPTION OF RESEARCH:

The research seeks to define the anatomical pathways and physical and biochemical mechanisms involved in the transport of products of photosynthesis, especially sugars, from leaves to the receiving cells of sink organs. Current emphasis is on the movement of the major translocated sugar in strawberry, sucrose, to, and its accumulation in, cells of the strawberry fruit. This involves evaluation of potential symplastic and apoplastic pathways, characterization of membrane transport mechanisms, and determining how sucrose transport and accumulation are regulated. Associated with this work are studies on metabolism of sucrose in strawberry fruit.

Research in fruit physiology is currently directed toward understanding the regulation of anthocyanin accumulation in ripening strawberry fruit. This involves measuring, during fruit development, the activity of key enzymes associated with anthocyanin synthesis and determining internal and environmental factors which influence their activity and/or biochemistry.

RELATED PUBLICATIONS:

Cheng, G. W. and P. J. Breen. 1991. Activity of phenylalanine ammonia-lyase (PAL) and concentration of anthocyanins and phenolics in developing strawberry fruit. J. Amer. Soc. Hort. Sci. 116:865-869.

Cheng, G. W. and P. J. Breen. 1992. Cell number and size in relation to fruit size among strawberry cultivars. J. Amer. Soc. Hort. Sci. 117:946-950.

Cheng, G. W., D. A. Malencik and P. J. Breen. 1994. UDP-glucoside:flavonoid O-glucosyltransferase from strawberry fruit. Phytochemistry 35:1435-1439.

Pomper, K. W. and P. J. Breen. 1995. Levels of apoplastic solutes in developing strawberry fruit. J. Expt. Bot. 46:743-752.

Pomper, K. W. and P. J. Breen. 1996. The effect of cell turgor on sugar uptake in strawberry fruit cortex tissue. Physiol. Plant. 96:324-332.

Pomper, K. W. and P. J. Breen. 1997. Expansion and osmotic adjustment of strawberry fruit during water stress. J. Amer. Soc. Hort. Sci. 122 (in press).

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Michael J. Burke

Date and Place of Degree: 1969, Iowa State University
Rank and Department: Professor, Horticulture

RESEARCH AREA: Plant stress physiology; frost survival of plants; ice nucleation active bacteria

DESCRIPTION OF RESEARCH:

My area of research and graduate teaching involves biophysical aspects of plant stress physiology. Most of this interest has been in plant behavior at low subfreezing temperatures. This has included characterizing the freezing process in plants and mechanisms of plant adaptation to freezing temperatures. Some specific areas of interest are:
1. Study of deep supercooling of plant tissue solutions to their homogeneous ice nucleation temperature near -40oC. Many angiosperm tree species supercool to -40oC in their stem tissues and flower buds. Research has characterized key properties of pla nts that allow supercooling.
2. Investigation of geographic and elevational (timberline) distributions of plants displaying deep supercooling as a survival mechanism. Plants that use deep supercooling have winter survival limits near or just below -40oC. This has ecological impli cations as -40oC temperatures occur on about half the land mass of North America and Eurasia.
3. Characterization of ice nucleation in plants in the temperature range from 0o to -10oC. Most of this work has involved ice nucleation active bacteria. We have been interested in molecular changes in the ice nucleator protein on the bacterial surfac e as the bacteria gain ice nucleation activity.

RELATED PUBLICATIONS:

George, M. F. and M. J. Burke. 1984. Supercooling of tissue water to extreme low temperature in overwintering plants. Trends Biochem. Sci. 9:211.

Burke, M. J. 1986. The glassy state and survival of anhydrous biological systems. In: Membranes, metabolism, and dry organisms. A. C. Leopold, ed. Cornell Press.

Rajashekar, C. and M. J. Burke. 1986. Methods to study the freezing process in plants. In: Protons and water: Structure and translocation, biomembranes, Part O. Methods of enzymology. L. Packer, ed. Academic Press.

Rogers, J. S., R. E. Stall, and M. J. Burke. 1987. Cold conditioning of the ice nucleation active bacterium, Erwinia herbicola. Cryobiology 24:270-279.

Burke, M. J. 1990. Surface properties and size of the ice nucleation site of ina bacteria: Theoretical considerations. Cryobiology 27:80-84.

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Paul M. Chen

Date and Place of Degree: 1976, University of Minnesota
Rank and Department: Professor, Horticulture

RESEARCH AREA: Postharvest physiology of pome fruits

DESCRIPTION OF RESEARCH:

The primary goal of the research project is to conserve pome fruit after harvest for a prolonged period and to ensure high dessert quality after storage. Current research is focused on different types of controlled atmosphere (CA) storage which will lengthen the storage life of fruit as well as minimize the storage disorder. Specific problems under investigation include:
1. Identification of certain biochemical changes in fruit during growth and development that may be used as maturity indices
2. A study of malic enzyme in fruit in relation to fruit maturity and storage life
3. A study of phospholipids and alcohol dehydrogenase in fruit in relation to storage disorders after storage

RELATED PUBLICATIONS:

Chen, P. M., D. M. Borgic, D. Sugar, and W. M. Mellenthin. 1986. Influence of fruit maturity and growing district on brown-core disorder in 'Bosc' pears. HortScience 21:1172.

Spotts, R. A. and P. M. Chen. 1987. Pre-storage heat treatment for control of decay of pear fruit. Phytopath. 77:1578.

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Tony H. H. Chen

Date and Place of Degree: 1981, University of Minnesota
Rank and Department: Professor, Horticulture

RESEARCH AREA: Stress physiology; molecular basis of plant adaptation to freezing and desiccation stress

DESCRIPTION OF RESEARCH:

Our laboratory is working on three research projects. The first project is on the molecular basis of cold hardening. We have found that abscisic acid (ABA) is capable of inducing freezing tolerance at warm temperatures, bypassing the requirement of low temperatures for cold acclimation. We have isolated cDNA clones representing the genes induced by ABA from bromegrass and a wild potato species. We are currently studying the roles of the ABA induced genes in the induction of freezing tolerance. The second project concerns the expression of the bacterial ice nucleation protein gene (inaZ) in plants. We have introduced the ice nucleation protein gene (inaZ) from Pseudomonas syringae pv. syringae into two diverse plant species: Nicotiana tabacum, a freezing sensitive species, and Solanum commersonii, a freezing tolerant species. In both species, expression of the inaZ protein results in an increase in ice nucleation activity over untransformed controls. The temperature of the warmest freezing event has been increased from approximately -12oC to -4oC. We are currently working on targeting the ice nuclei to different cellular locations, and studying the expression of ice nuclei on the freezing tolerance of plants. The third project is concerned with photoperiod controlled gene expression in woody plants. The annual cycle of woody plants consists of distinct physiological stages defined by bud burst, maturity induction, vegetative maturity, maximum rest, and end of rest. Although it is well established that dormancy and first stage of cold acclimation are responsive to photoperiod, little is known about photoperiod controlled gene expression in different growth stages of the annual growth cycle. We are studying the molecular events associated with photoperiod responses in poplars and their hybrids. Using this system, we have shown that the poplar 32 kD bark storage protein (BSP) accumulates rapidly in plants exposed to short days. We have isolated and sequenced a cDNA which encodes for the 32 kD BSP and have shown that short-day controlled protein accumulation is correlated with changes in the steady state levels of bark storage protein mRNA. Currently, we are characterizing the BSP gene and its regulation.

RELATED PUBLICATIONS:

Tanino, K. K., C. J. Weiser, L. H. Fuchigami, and T. H. H. Chen. 1990. Water content during abscisic acid induced freezing tolerance in bromegrass cells. Plant Physiol. 93:460-464.

Tanino, K. K., T. H. H. Chen, L. H. Fuchigami, and C. J. Weiser. 1990. Biochemical changes associated with abscisic acid induced frost hardiness in bromegrass cells. Plant and Cell Physiol. 31(4):505-511.

Lee, S. P., T. H. H. Chen, and L. H. Fuchigami. 1991. Changes in the translatable RNA population during abscisic acid induced freezing tolerance in bromegrass suspension culture. Plant and Cell Physiol. 32(1):45-56.

Coleman, G. D., T. H. H. Chen, S. G. Ernst, and L. H. Fuchigami. 1991. Photoperiod control of poplar bark storage protein accumulation. Plant Physiol. 96:686-692.

Coleman, G. D., T. H. H. Chen, and L. H. Fuchigami. 1992. Complementary DNA cloning of poplar bark storage protein and control of its expression by photoperiod. Plant Physiol. 98:687-693.

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Laurence (Larry) S. Daley

Date and Place of Degree: 1975, University of California, Davis
Rank and Department: Associate Professor, Horticulture

RESEARCH AREA: Physiological and biochemical characterization of plant germplasm

DESCRIPTION OF RESEARCH:

Laboratory-oriented physiological, biochemical, biophysical, biochemical-plant pathological, gene expression research to identify and characterize plant germplasm (Corylus, Fragaria, Mentha, Prunus, Pyrus, Rubus, Ribes, Vaccinium, Vitis, and others).

RELATED PUBLICATIONS:

Eskelsen, S. R., G. D. Crabtree, R. B. Boone, G. M. Volk, L. Ning, and L. S. Daley. 1994. Visible spectroscopy of herbicides: Monitoring in vivo effects and modeling off-target movement. Spectroscopy 7(2):34-40.

Ning, L., R. Ozanich, L. S. Daley, and J. B. Callis. 1994. Construction of an imaging spectrophotometer and its application to plant sciences. Spectroscopy 9(7):41-48.

Feng, W., L. Ning, L. S. Daley, Y. Moreno, A. Azarenko, and R. S. Criddle. 1994. Determination of effective temperature minima for CAM carboxylation in diverse plants by scanning microcalorimetry. Plant Physiol. Biochem. 32:319-330.

Feng, W., L. Ning, L. S, Daley, Y. Moreno, A. Azarenko, and R. S. Criddle. 1994. Theoretical fitting of energetics of CAM path to calorimetric data. Plant Physiol. Biochem. 32:591-598.

Gardea, A. A., L. S. Daley, R. L. Kohnert, A. H. Soeldner, L. Ning, P. B. Lombard, and A. N. Azarenko. 1994. Proton NMR signals associated with eco- and endodormancy in winegrape buds. Scientia Hort. 56:339-358.

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Paul S. Doescher

Date and Place of Degree: 1983, Oregon State University
Rank and Department: Associate Professor, Rangeland Resources

DESCRIPTION OF RESEARCH:

Physiological and morphological characteristics of grazed and ungrazed populations of Festuca idahoensis. Ecophysiological dynamics in juniper (Juniperus occidentalis) and sagebrush (Artemisia tridentata) dominated ecosystems. Effect of cattle on establishment and growth of conifer seedlings on plantations of southwest Oregon.

RELATED PUBLICATIONS:

Doescher, P. S., S. D. Tesch, and W. E. Drewien. 1989. Water relations and growth of conifer seedlings following three years of cattle grazing on a southwest Oregon plantation. NW Sci. 63:232-240.

Doescher, P. S., R. F. Miller, J. J. Wang, and J. Rose. 1990. Effects of nitrogen availability on growth and photosynthesis of Artemisia tridentata spp. wyomingensis. Great Basin Naturalist 50:9-19.

Karl, M. G. and P. S. Doescher. 1991. Monitoring roots of grazed rangeland vegetation with the root periscope/mini-rhizotron technique. J. Range Mgmt. 44:296-299.

Miller, R. F., P. S. Doescher, and J. Wang. 1991. Response of competing Artemisia tridentata spp. wyomingensis and Stipa thurberiana to nitrogen amendments. Amer. Midl. Nat. 125:104-113.

Karl, M. G. and P. S. Doescher. 1993. Regulating competition on conifer plantations with prescribed cattle grazing. For. Sci. 39:405-418.

Jaindl, R. G., P. S. Doescher, and L. E. Eddleman. 1993. Influence of water relations on the limited expansion of Pinus monaphylla into adjacent Cercocarpus ledifolius communities in the Great Basin. For. Sci. 39:629-643.

Nasri, M. and P. S. Doescher. 1994. Effect of competition by cheatgrass on shoot growth of Idaho fescue. J. Range Manage. (in press).

Nasri, M. and P. S. Doescher. 1994. Effect of temperature on growth of cheatgrass and Idaho fescue. J. Range Manage. (in press).

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Robert P. Doss

Date and Place of Degree: 1974, University of California, Davis
Rank and Department: Plant Physiologist, USDA - ARS, Associate Professor (Courtesy), Horticulture

RESEARCH AREA: Physiology of flowering; plant-disease and plant-insect interactions

DESCRIPTION OF RESEARCH:

Characterization of genes involved in floral induction and floral evocation. Characterization of plant-insect and (specific features of) plant-fungus interactions. Current work involves the following:
1. Isolation of photoperiodic-floral-induction-specific genes from Perilla crispa
2. Isolation and characterization of an insecticide synergists from yew
3. Investigation of the process of spore attachment exhibited by Botrytis cinerea

RELATED PUBLICATIONS:

Doss, R. P. and K. J. R. Johnson. 1991. (Z)-oxacyclotridec-10-en-2-one does not appear to be responsible for the resistance to adult alfalfa weevil feeding exhibited by Medicago rugosa. J. Chem. Ecol. 17:535-542.

Doss, R. P., C. H. Shanks, Jr., T. M. Sjulin, and T. K. L. Garth. 1991. Evaluation of some Fragaria chiloensis x (F. x ananassa) seedlings for resistance to black vine weevil. Scientia Hort. 48:233- 239.

Chastagner, G. A., K. L. Riley, and R. P. Doss. 1992. An attempt to produce an apothetical state of Botrytis elliptica in vitro. Acta Hort. 325:689-693.

Doss, R. P., S. W. Potter, G. A. Chastagner, and J. K. Christian. 1993. Adhesion of nongerminated Botrytis cinerea conidia to several substrata. Appl. Environ. Microbiol. 59:1786-1791.

Doss, R. P. 1992. Phytochemical factors that influence root weevil feeding on Rhododendron. A review. Phytochem. (Life Sci. Adv.) 11:253-259.

Doss, R. P. 1993. Flowering does not influence composition of abundant proteins from the duckweed Lemna aequinoctialis, strain 6746. Plant Physiol. (Life Sci. Adv.) 12:101-108.

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Leslie H. Fuchigami

Date and Place of Degree: 1969, University of Minnesota
Rank and Department: Professor, Horticulture

RESEARCH AREA: Regulation of dormancy and stress physiology

DESCRIPTION OF RESEARCH:

Regulation of the development and breaking of dormancy and the development of freezing and desiccation resistance in temperate woody plant species. Recent research has focused on the role of near-lethal (sub-lethal) stresses on the breaking of winter dormancy, plant hardiness, and recovery. We are also studying the relationship of oxidizing agents, free radicals, reducing agents, and scavengers of free radicals on dormancy and hardiness.

Other research interests include the postharvest physiology and establishment of deciduous and herbaceous plants.

RELATED PUBLICATIONS:

Shirazi, A. M. and L. H. Fuchigami. 1992. Recovery of plants from near-lethal stresses. Oecologia 93:429-434.

Coleman, G. D., J. M. Englert, T. H. H. Chen, and L. H. Fuchigami. 1993. Physiological and environmental requirements for poplar bark storage protein degradation. Plant Phys. 102:53-59.

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Barbara L. Gartner

Date and Place of Degree: 1990, Stanford University
Rank and Department: Assistant Professor, Forest Products

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David B. Hannaway

Date and Place of Degree: 1979, University of Kentucky
Rank and Department: Professor, Crop and Soil Science

RESEARCH AREA: Forage production, management, and computer modeling

DESCRIPTION OF RESEARCH:

Developing, validating, and implementing forage management systems for alfalfa and grass-legume pastures. Work has concentrated on nitrogen fixation of forage legumes and N nutrition and phenological development of alfalfa. Work is beginning on pasture renovation, feed budgeting, and pasture modeling.

RELATED PUBLICATIONS:

Mao, M. and D. B. Hannaway. 1990. Evaluation of Rhizobium meliloti transconjugant for increased nodulation and biological nitrogen fixation in alfalfa. J. Plant Nutr. 13:795-815.

Bolte, J. P., D. B. Hannaway, P. E. Shuler, and P. J. Ballerstedt. 1991. An intelligent frame system for cultivar selection. Al Applications 5:21-31.

Hu, S. T., D. B. Hannaway, and H. W. Youngberg. 1992. Forage resources of China. PUDOC. The Netherlands. 327 pp.

Hannaway, D. B., J. P. Bolte, P. E. Shuler, P. J. Ballerstedt, and M. Ben-Younes. 1992. ACE: Alfalfa cultivar expert. J. Prod. Agric. (in press).

Hannaway, D. B., P. E. Shuler, J. P. Bolte, and M. J. Miller. 1992. Legume ID: A ToolBook multimedia module. J. Nat. Res. Educ. (in press).

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Terri L. Lomax

Date and Place of Degree: 1983, Stanford University
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Molecular biology of plant growth and development; cellular signal transduction chains; auxin physiology and transport

DESCRIPTION OF RESEARCH:

The plant growth hormone auxin plays an integral role in the control of development and the response to environmental stimuli of higher plants. However, very little is known about the primary auxin receptors and subsequent steps in the mode of action within the cell. We are combining physiological, cellular, and molecular techniques to study the steps along the transduction chain between auxin perception and response, beginning with components of the plasma membrane which participate in the initial response to auxin; the carriers responsible for auxin uptake into the cell, GTP-binding proteins, and activation of protein kinases in response to auxin.

Auxin uptake and efflux receptors appear to be tightly regulated during development and they influence both the responsiveness of the cell to the hormone and the concentration of auxin throughout the tissue. Using membrane vesicles from isolated plant plasma membranes, we have demonstrated that auxin is taken up into the cell via a specific, electrogenic uptake carrier protein. We have identified the transport proteins using a photoaffinity label. Purification of the proteins will allow analysis of the regulation of expression of the corresponding genes, using the antibodies and oligonucleotide probes generated after microsequencing the isolated proteins.

We are also examining the role of second messengers in auxin action. The membrane proteins called G proteins (GTP-binding proteins) play a leading role in signal transmission for many animal hormones, neurotransmitters, and growth factors, as well as with the uncontrolled growth and other aberrant effects of oncogenes. Our interest lies in demonstrating that plant hormones utilize a similar mechanism, identifying the enzymes involved, and characterizing their regulation in response to auxin. Currently, this involves the study of auxin interaction with G proteins and CA++-dependent plasma membrane protein kinase activity and the isolation of the genes encoding those proteins.

RELATED PUBLICATIONS:

Hicks, G. R., D. L. Rayle, and T. L. Lomax. 1989. The diageotropic a mutant of tomato lacks high specific activity auxin-binding sites. Science 245:52-54.

Hicks, G. R., D. L. Rayle, A. M. Jones, and T. L. Lomax. 1989. Specific photoaffinity labeling of two plasma membrane polypeptides with an azido auxin. Proc. Natl. Acad. Sci. USA 86:4948-4952.

Lomax, T. L. 1990. Molecular communication in higher plants. The New Biologist 2:133-135.

Perdue, D. O. and T. L. Lomax. 1991. Characterization of GTP binding and hydrolysis in plasma membranes of zucchini (Cucurbita pepo z.). Plant Physiol. Biochem. 30:220-225.

Lomax, T. L. 1991. Specific auxin binding proteins in the plasma membrane: Receptors or transporters? Biochem Soc. Trans. 20:64-69.

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Richard F. Miller

Date and Place of Degree: 1976, New Mexico State University, Las Cruces
Rank and Department: Professor, Rangeland Resources

RESEARCH AREA: Plant community ecology and ecophysiology

DESCRIPTION OF RESEARCH:

Evaluation of processes and mechanism of plant competition and succession in the cold desert shrub steppe and juniper woodlands. Current work is the relationship of juniper woodland structure and plant competition with soil factors. Rainout shelters are also being completed to evaluate the impacts of changing precipitation patterns on chemical and physical processes in cold desert shrub communities.

RELATED PUBLICATIONS:

Miller, R. F. and L. I. Shultz. 1987. Water relations and leaf morphology of Juniperus occidentalis in the northern Great Basin. Forest Sci. 33(3):690-706.

Miller, R. F. 1988. Comparison of water use by Artemisia tridentata spp. wyomingensis and Chrysothamnus viscidiflorus spp. viscidiflorus. J. Range Manage. 40:58-62.

Miller, R. F., P. S. Doescher, and J. Wang. 1991. Response of Artemisia tridentata spp. wyomingensis and Stipa thurberiana to nitrogen amendments. Amer. Midland Naturalist 125:104-113.

Miller, R. F. and J. A. Rose. 1992. Growth and carbon allocation of Agropyron desertorum following autumn defoliation. Oecologia 89:482-486.

Angell, R. F. and R. F. Miller. 1994. Simulation of leaf conductance in Juniperus occidentalis. Forest Sci. 40:5-17.

Miller, R. F., T. Svejcar, J. A. Rose, and M. McInnis. 1994. Plant development, water relations and carbon allocation of heart-podded hoary cress. J. Agron. 86:487-491.

Miller, R. F. and P. E. Wigand. 1994. Holocene changes in semiarid woodlands: Response to climate, fire and human activities in the Great Basin. BioScience 44:465-473.

Miller, R. F., T. Svejcar, and N. E. West. 1994. Implications of livestock grazing the sagebrush steppe: Plant composition. In: Ecological implications of livestock herbivory in the west. M. Vavra, B. Laycock, and R.Pieper, eds. Soc. Range Management. Denver CO. pp. 101-147.

Miller, R. F. and J. A. Rose. The historic expansion of Juniperus occidentalis (western juniper) in southeastern Oregon. Great Basin Naturalist (in press).

Jandl, R., P. Doescher, and R. F. Miller. Persistence of Idaho fescue on degraded rangelands: Adaptation to defoliation or tolerance. J. Range Manage. (in press).

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Machteld C. Mok

Date and Place of Degree: 1975, University of Wisconsin, Madison
Rank and Department: Professor, Horticulture

RESEARCH AREA: Genetic regulation of cytokinin metabolism; genetic improvement of horticultural crops using biotechnology; molecular biology of Fe efficiency

DESCRIPTION OF RESEARCH:

Cytokinins are known to play a crucial role in plant development. However, the mechanisms controlling the levels of cytokinins in plant tissues are poorly understood. The goal of our research is to identify and characterize the mechanisms regulating cytokinin metabolism. Recent findings of the project are: identification of novel cytokinin metabolites, O-xylosylzeatin, and derivatives; isolation of four zeatin-specific enzymes; and generation of monoclonal antibodies to two of the enzymes. The antibodies have been used to isolate genes encoding the enzymes and to study the expression of the enzymes during development.

The second research area deals with the design and application of unconventional strategies aimed at the genetic improvement of horticultural plants. Ongoing projects include: regeneration and transformation of fruit tree germplasm, and selection of somaclonal variants of fruit tree rootstocks with increased tolerance to iron-limiting conditions; and regeneration and transformation of pepper.

The third research area concerns the mechanisms involved in the adaptation of dicots to low Fe. We have characterized the responses to low Fe in cultured tissues of Pyrus (pear) species and quince. Current efforts are focused on isolation and characterization of genes that play a role in these responses, with an emphasis on the genes encoding Fe reductases.

RELATED PUBLICATIONS:

Dolcet-Sanjuan, R., D. W. S. Mok, and M. C. Mok. 1992. Characterization and in vitro selection for iron efficiency in Pyrus and Cydonia. In Vitro Cell. Dev. Biol. 28P:25-29.

Mok, D. W. S., M. C. Mok, R. C. Martin, N. V. Bassil, and D. W. S. Lightfoot. 1992. Zeatin metabolism in Phaseolus: Enzymes and genes. In: Progress in plant growth regulation. C. M. Karssen, L. C. van Loon, and D. Vreugdenhil, eds. Kluwer Dordrecht. Netherlands. pp. 597-606.

Martin, R., M. C. Mok, and D. W. S. Mok. 1993. Cytolocalization of zeatin O-xylosyltransferase in Phaseolus. Proc. Natl. Acad. Sci. USA 90:953-957.

Bassil, N. V., D. W. S. Mok, and M. C. Mok. 1993. Partial purification of a cis-trans- isomerase of zeatin from immature seed of Phaseolus vulgaris L. Plant Physiol. 102:867-872.

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David D. Myrold

Date and Place of Degree: 1984, Michigan State University
Rank and Department: Professor, Crop and Soil Science

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William M. Proebsting

Date and Place of Degree: 1978, Cornell University
Rank and Department: Professor, Horticulture

RESEARCH AREA: Genetic and photoperiodic regulation of shoot development; gibberellin metabolism and molecular biology

DESCRIPTION OF RESEARCH:

My program presently centers on two sets of developmental mutants of pea with altered stem elongation and photoperiod response. The major genes controlling plant stature regulate biosynthesis of, and plant response to, gibberellins. We have been studying the effects of these genes on gibberellin metabolism and stem elongation. Efforts are underway to clone genes involved in gibberellin biosynthesis. By isolating these genes, we hope to determine their relationship to specific tissues and organs, and stage of development, as well as the effects of light, photoperiod and other environmental factors.

The major genes controlling flowering and photoperiod response comprise a classic system for the study of juvenility and photoperiod. In pea, hormones clearly mediate the effects of photoperiod on plant growth. Gibberellins play a role in photoperiodic control of internode elongation, but their effects on apical growth and development, including flowering, is less clear. We have identified gibberellins in pea associated with photoperiod and the photoperiod genes. We are presently confirming the identity of these gibberellins and assessing their effects on plant development.

Another mutant, designated Np (Neoplastic pod), regulates an organ-specific response to insect predation and plant hormones. When grown under low UV-light, pods on Np plants develop pustular growths called neoplasms. Seeds are the source of neoplastic stimulus and the plant growth regulators gibberellic acid and naphthaleneacetic acid mimic the effects of the seeds. When pea weevils lay their eggs on Np pods, callus forms under the egg, pushing the egg away from the pod surface. Extracts of gravid weevils also stimulate callus formation, which is anatomically and physiologically distinguishable from the neoplasms stimulated by seed. Thus, Np conditions control of cell division by a compound found in pea weevil and to compounds in developing seeds, presumably native gibberellins and auxins. We have begun both characterization of the compound extracted from weevil and isolation of the Np gene.

RELATED PUBLICATIONS:

Guo, W. W., W. M. Proebsting, S. W. Potter, L. S. Daley, and J. R. Potter. 1987. Development of the alt mutant of Pisum sativum L. Plant Physiol. 85:1089-1093.

Proebsting, W. M., S. P. Maggard, and W. W. Guo. 1990. The relationship of thiamine to the Alt locus of Pisum sativum L. J. Plant Physiol. 136:231-235.

Bassil, N. V., W. M. Proebsting, L. W. Moore, and D. Lightfoot. 1991. Propagation of hazelnut stem cuttings using Agrobacterium rhizogenes. HortScience 26:1058-1060.

Proebsting, W. M., P. Hedden, M. J. Lewis, S. J. Croker, and L. N. Proebsting. 1993. Gibberellin concentration and translocation in genetic lines of pea. Effect of grafting. Plant Physiol. 100:1354- 1360.

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Patricia A. Wheeler

Date and Place of Degree: 1976, University of California, Irvine
Rank and Department: Professor, Oceanography

RESEARCH AREA: Nitrogen metabolism in marine phytoplankton, macroalgae, and bacteria

DESCRIPTION OF RESEARCH:

Laboratory and field investigations of uptake of inorganic and organic sources of nitrogen. Current investigations are focused on the regulation of uptake and determination of the relationship between uptake rates, cell or tissue composition, and growth rates. Specific problems under investigation include:
1. The relative use of ammonium and nitrate nitrogen by marine phytoplankton
2. The competition between marine bacteria and phytoplankton for inorganic nitrogen sources
3. The relative roles of nitrogen and phosphorus in regulating macroalgal growth rates in estuarine and coastal waters
Current research activities include the application of 15N tracers to the analysis of ammonium uptake and remineralization rates in natural populations of marine plankton, use of continuous cultures to determine the relationship between nutrient supply rates and tissue composition of macroalgae, and analysis of the uncoupling of short-term uptake rates and growth rates of macroalgae.

RELATED PUBLICATIONS:

Wheeler, P. A. and D. L. Kirchman. 1986. Utilization of inorganic and organic forms of nitrogen by bacteria in marine systems. Limnol. Oceanogr. 31:998-1009.

Kokkinakis, S. A. and P. A. Wheeler. 1987. Nitrogen uptake and phytoplankton growth in temperate coastal upwelling regions. Limnol. Oceanogr. 32:1112-1123.

Kokkinakis, S. A. and P. A. Wheeler. 1988. Uptake of ammonium and urea in the northeast Pacific: Comparison between netplankton and nanoplankton. Mar. Ecol. Prog. Ser. (in press).

Fujita, R. M., P. A. Wheeler, and R. L. Edwards. 1988. Metabolic regulation of ammonium uptake by Ulva rigida (Chlorophyceae): A compartmental analysis of the rate-limiting step for uptake. J. Phycol. 24:560-566.

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Steven R. Radosevich

Date and Place of Degree: 1972, Oregon State University
Rank and Department: Professor, Forest Science and Crop and Soil Science

RESEARCH AREA: Physiological ecology; physiological basis for plant-plant interference; mechanisms of herbicide resistance

DESCRIPTION OF RESEARCH:

Initial research concentrated on the mechanism for developed herbicide resistance in formerly susceptible plant species. This research was the first that documented differential herbicide resistance, and ultimately led to the discovery of an altered mechanism of electron transport in PSII.

Insight also was gained concerning the mechanism of action of many photosynthetic inhibitors believed to function on the reducing side of PSII. The research was expanded later to include the causes for differential fitness noted between the herbicide resistant and susceptible biotypes. This project is continuing with plant material believed to be differentially tolerant to dinitroaniline and phenoxy-phenosypropanoate herbicides.

Other research focuses on the proximity, physiological, morphological, and environmental factors that influence the outcome of plant-plant associations. This research relies heavily on the basic yield-density relationships, while describing the outcome of competition on the basis of physiological, morphological, or anatomical differences among the species. The principles being generated are remarkably similar for both agricultural and early forest production systems.

RELATED PUBLICATIONS:

Sims, J. D., A. J. Stemler, and S. R. Radosevich. 1981. Differential light response to photosynthesis by triazine resistant and susceptible Senecio vulgaris biotypes. Plant Physiol. 67(4):744-748.

Holt, J. S., S. R. Radosevich, and A. J. Stemler. 1983. Differential efficiency of photosynthetic oxygen evolution in flashing light in triazine-resistant and triazine- susceptible biotypes of Senecio vulgaris L. Biochimica Biophysica Acta. 722:245-255.

Roush, M. L. and S. R. Radosevich. 1985. Relationship between growth rate and competitiveness of four annual weeds. J. Appl. Ecol. 22:895-905.

Shainsky, L. J. and S. R. Radosevich. 1986. Effects of manzanita density on the growth and water status of conifer seedlings. J. Appl Ecol. 23:957-965.

Radosevich, S. R. and M. L. Roush. 1988. The role of competition in agriculture. In: Perspectives on competition. J. Grace and D. Tillman, eds. Academic Press.

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Timothy L. Righetti

Date and Place of Degree: 1980, University of California, Davis
Rank and Department: Professor, Horticulture

RESEARCH AREA: Mineral uptake, transport, and partitioning in woody plants

DESCRIPTION OF RESEARCH:

The major research goals involve the identification of plant characteristics that affect the uptake and transport of nitrogen in perennial woody plants. Since high nitrogen fruit is associated with poor fruit quality, the nitrogen status of developing fruit is important. Current investigations are utilizing 15N as a nitrogen tracer in pear trees. The portions of leaf and fruit nitrogen that originate from either the soil or tree reserves are being evaluated. A strong emphasis is on developing strategies to maximize uptake efficiency and therefore minimize environmental hazards. At the same time, it is important to minimize the nitrogen concentration in fruit while maintaining optimal nitrogen levels in the rest of the tree. Specific research objectives include:
1. Evaluating the partitioning of nitrogen between leaves and fruit as affected by the nitrogen status of an entire tree and the position of leaves and fruit within the canopy
2. Developing nondestructive approaches to measure tree biomass and mineral concentrations to better describe the dynamics of tree behavior in an orchard setting
3. Developing diagnostic procedures to determine optimal management practices in tree fruit
Other areas of research interest include factors affecting nitrogen fixation in woody species. Work is concentrated on Frankia nodulated genera in the Rosaceae.

RELATED PUBLICATIONS:

Kyle, N. E., J. Jakobek, R. A. Backhaus, J. C. Stutz, and T. L. Righetti. 1986. Micrografting between N- fixing and non-N-fixing genera of the Rosaceae. Bot. Gazette 147(3):243-246.

Sanchez, E., T. L. Righetti, D. Sugar, and P. B. Lombard. 1991. Recycling of nitrogen in field-grown 'Comice' pear. J. Hort. Sci. 66:479-486.

Sanchez, E., T. L. Righetti, D. Sugar, and P. B. Lombard. 1992. Effects of timing of nitrogen application on nitrogen partitioning between vegetative, reproductive, and structural components of mature 'Comice' pears. J. Hort. Sci. 67(1):51-58.

Sugar, D., T. L. Righetti, E. E. Sanchez, and H. Khemira. 1992. Management of N and Ca in pear trees for enhancement of fruit resistance to postharvest decay. HortTech. 2(3):382-387.

Sanchez, E. E., H. Khemira, D. Sugar, and T. L. Righetti. 1994. Nitrogen management in orchards. In: Nitrogen fertilization and the environment. P. Bacon, ed. Marcel Dekker, Inc. (in press).

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Bernadine C. Strik

Date and Place of Degree: 1987, University of Guelph, Ontario, Canada
Rank and Department: Professor, Horticulture

RESEARCH AREA: Production research in berry and grape crops; factors that affect yield and quality in berry crops

DESCRIPTION OF RESEARCH:

Identification of environmental or cultural factors that affect flower bud initiation, yield, and/or quality in berry crops. Also, various modifications to current commercial production practices are being studied to maximize yield and quality. Specific problems under investigation include:
1. Effect on cane length, winter injury, and date of renovation (mowing) on yield components of 'Marion' blackberry
2. Factors affecting winter injury of 'Marion' blackberry
3. Effect of sand application on cranberry yield components and pest pressure
4. Biology and management of grape phylloxera in Oregon
5. Vegetative and reproductive growth responses of blueberry to pruning severity in Oregon

RELATED PUBLICATIONS:

Strik, B. C. and J. T. A. Proctor. 1988. Growth analysis of field-grown strawberry genotypes differing in yield. I. The matted row system. J. Amer. Soc. Hort. Sci. 113(6):894-899.

Strik, B. C. and J. T. A. Proctor. 1988. Growth analysis of field-grown strawberry genotypes differing in yield. II. The hill system. J. Amer. Soc. Hort. Sci. 113(6):899-904.

Strik, B. C. and J. T. A. Proctor. 1988. The relationship between achene number, achene density, and berry fresh weight in strawberry. J. Amer. Soc. Hort. Sci. 113:620-623.

Strik, B. C. and J. T. A. Proctor. 1988. The importance of growth during flower bud differentiation to maximizing yield in strawberry genotypes. Fruit Var. J. 42:45-48.

Strik, B. C. and J. T. A. Proctor. 1988. Yield component analysis of strawberry genotypes differing in productivity. J. Amer. Soc. Hort. Sci. 113:124-129.

Strik, B. C., T. R. Roper, C. J. DeMoranville, J. R. Davenport, and A. P. Poole. 1991. Cultivar and growing region influence return bloom of cranberry uprights. HortScience 26:1366-1367.

Strik, B. C. and A. Poole. 1991. Time and severity of pruning effects on cranberry yield components and fruit anthocyanin content. HortScience 26:1462-1464.

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David T. Tingey

Date and Place of Degree: 1972, North Carolina State University
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Environmental physiology; effects of environmental stresses (air pollutants) on plants and plant processes

DESCRIPTION OF RESEARCH:

Determination of the effects (growth and physiological) of air pollutants on plants. Current investigations are focused on understanding why plant sensitivity to air pollutants changes with plant phenology. Research is also being conducted to quantify pollutant uptake and the associated plant response. The ultimate goal is to develop a dose-response model which will model pollutant uptake and establish the internal concentrations required to elicit a response. Specific research problems include:
1. Plant water relations: The experimental control of plant water status and the influence of plant water status on plant response to air pollutants
2. Ozone physiology: Ozone-induced changes in plant metabolism and the quantification of ozone effects on plants
3. Plant gas exchange: Determination of ozone uptake rates and its subsequent effects on gas exchange
Additional research and data analysis is being conducted to determine the importance of temporal variation (e.g. peak concentration, duration, respite time, etc.) in pollutant exposure on plant response.

RELATED PUBLICATIONS:

Tingey, D. T. and W. E. Hogsett. 1985. Water stress reduced ozone injury via a stomatal mechanism. Plant Physiol. 77:944-947.

Taylor, G. E., Jr., D. T. Tingey, and C. A. Gunderson. 1986. Photosynthesis, carbon allocation, and growth of sulfur dioxide ecotypes of Geranium carolianum L. Oecologia 68:350-357.

Tingey, D. T., K. D. Rodecap, E. H. Lee, T. J. Moser, and W. E. Lee. 1986. Ozone alters the concentrations of nutrients in bean tissue. Agewandte Botanik 61:481-493.

Lee, E. H., D. T. Tingey, and W. E. Hogsett. 1988. Evaluation of ozone exposure indices in exposure- response relationships. Env. Pollution 53:43-62.

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Nan C. Vance

Date and Place of Degree: 1988, Oregon State University
Rank and Department: Plant Physiologist, USDA Forsest Service, Assistant Professor, Forest Science

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William E. Winner

Date and Place of Degree: 1978, University of Calgary
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Stress physiology; plant responses to multiple stresses; environmental physiology of plants

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Ronald E. Wrolstad

Date and Place of Degree: 1964, University of California, Davis
Rank and Department: Professor, Food Science and Technology

RESEARCH AREA: The chemical composition of fruits and vegetables and its influence on quality

DESCRIPTION OF RESEARCH:

The chemical composition of foods and its relationship to quality broadly describes my research interests. Fruit juices are the commodity of major interest, with the changes in the sugar, non-volatile acid, anthocyanin pigment, phenolic, and amino acid profiles during processing and storage being investigated. Color is the quality attribute receiving most attention, with both anthocyanin pigment degradation and nonenzymic browning reactions being studied. Both the analytical methods and the compositional data base are also used to develop better methods for determining the authenticity of fruit juices.

RELATED PUBLICATIONS:

Wrolstad, R. E., G. Skrede, P. Lea, and G. Enersen. 1990. Influence of sugar on anthocyanin pigment stability in frozen strawberries. J. Food Sci. 55:1064-1065, 1072.

Rommel, A., D. A. Heatherbell, and R. E. Wrolstad. 1990. Red raspberry juice and wine: Effect of processing and storage on anthocyanin pigment composition, color, and appearance. J. Food Sci. 55:1011-1017.

Spanos, G. A., R. E. Wrolstad, and D. A. Heatherbell. 1990. The influence of processing and storage on the phenolic composition of apple juice. J. Agric. Food Chem. 38:1565-1571.

Wrolstad, R. E. 1991. Ethical issues concerning food adulteration. Food Tech. 45(5):108, 112, 114, 116-117.

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Donald B. Zobel

Date and Place of Degree: 1968, Duke University
Rank and Department: Professor, Botany and Plant Pathology

RESEARCH AREA: Autecology of forest species

DESCRIPTION OF RESEARCH:

My interests are in the relationship of environment and plant characteristics to distributions of native plants. My physiologically-related research interests are: water relations, especially comparative water relations in trees from climates with dry periods in contrasting seasons; physiological changes in trees affected by grazing and lopping; and adaptive responses of plants to deposit of volcanic tephra.

RELATED PUBLICATIONS:

Zobel, D. B. and J. A. Antos. 1991. Growth and development of natural seedlings of Abies and Tsuga in old-growth forest. J. Ecology 79:985-998.

Zobel, D. B. and J. A. Antos. 1992. Survival of plants buried for eight growing seasons by volcanic tephra. Ecology 73:698-701.

Morrissey, L. A., D. B. Zobel, and G. P. Livingston. 1993. Significance of stomatal control on methane

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