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Plant Biology

2002

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Articles 1 - 28 of 28

Full-Text Articles in Life Sciences

Epigenetic History Of An Arabidopsis Trans-Silencer Locus And A Test For Relay Of Trans-Silencing Activity, Huaxia Qin, Albrecht G. Von Arnim Dec 2002

Epigenetic History Of An Arabidopsis Trans-Silencer Locus And A Test For Relay Of Trans-Silencing Activity, Huaxia Qin, Albrecht G. Von Arnim

Plant Sciences Publications and Other Works

Background

Meiotically heritable epimutations affecting transgene expression are not well understood, even and in particular in the plant model species, Arabidopsis thaliana. The Arabidopsis trans-silencer locus, C73, which encodes a fusion protein between the repressor of photomorphogenesis, COP1, and green fluorescent protein (GFP-COP1), heritably modifies the expression pattern and cop1-like cosuppression phenotypes of multiple GFP-COP1 target loci by transcriptional gene silencing.

Results

Here we describe three additional features of trans-silencing by the C73 locus. First, the silencing phenotype of C73 and of similar complex loci was acquired epigenetically over the course of no more than two plant generations via ...


Site-Specific Recombination-Based Genetic System For Reporting Transient Or Low-Level Gene Expression, N. Carol Casavant, Gwyn A. Beattie, Gregory J. Phillips, Larry J. Halverson Jul 2002

Site-Specific Recombination-Based Genetic System For Reporting Transient Or Low-Level Gene Expression, N. Carol Casavant, Gwyn A. Beattie, Gregory J. Phillips, Larry J. Halverson

Microbiology Publications

We report here the construction, characterization, and application of a plasmid-based genetic system that reports the expression of a target promoter by effecting an irreversible, heritable change in a bacterial cell. This system confers strong repression of the reporter gene gfp in the absence of target promoter expression and utilizes the site-specific recombination machinery of bacteriophage P22 to trigger high-level reporter gene expression in the original cell and its progeny after target gene induction. We demonstrate the effectiveness of this genetic system by tailoring it to indicate the availability of arabinose to the biological control agent Enterobacter cloacae JL1157 in ...


Myriophyllum Spicatum Invasion In Cave Run Lake, Kentucky, Rob A. Tewes May 2002

Myriophyllum Spicatum Invasion In Cave Run Lake, Kentucky, Rob A. Tewes

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Rob A Tewes on May 1, 2002.


Accumulation Of Microbial Biomass Within Particulate Organic Matter Of Aging Golf Greens, Mine Kerek, Rhae A. Drijber, William L. Powers, Robert C. Shearman, Roch E. Gaussoin, Anne Streich May 2002

Accumulation Of Microbial Biomass Within Particulate Organic Matter Of Aging Golf Greens, Mine Kerek, Rhae A. Drijber, William L. Powers, Robert C. Shearman, Roch E. Gaussoin, Anne Streich

Agronomy & Horticulture -- Faculty Publications

Microbial biomass (MB) is a key variable controlling soil organic matter dynamics in soil. Currently, there is little information on the amount and significance of MB in highly managed golf greens. Our objective was to determine the amount and distribution of MB within soil structural components of golf greens and its relationship to the location of organic substrates. During 1996, 47 greens were sampled from 12 golf courses within Nebraska (USA). Microbial biomass, determined as extractable lipid phosphate on field-moist soils, increased linearly with age of green (Y = 19.39 + 3.54x; r2 = 0.87, P = 0.001). In ...


Characterization Of Fro1, A Pea Ferric-Chelate Reductase Involved In Root Iron Acquisition, Brian M. Waters, Dale G. Blevins, David J. Eide May 2002

Characterization Of Fro1, A Pea Ferric-Chelate Reductase Involved In Root Iron Acquisition, Brian M. Waters, Dale G. Blevins, David J. Eide

Agronomy & Horticulture -- Faculty Publications

To acquire iron, many plant species reduce soil Fe(III) to Fe(II) by Fe(III)-chelate reductases embedded in the plasma membrane of root epidermal cells. The reduced product is then taken up by Fe(II) transporter proteins. These activities are induced under Fe deficiency. We describe here the FRO1 gene from pea (Pisum sativum), which encodes an Fe(III)-chelate reductase. Consistent with this proposed role, FRO1 shows similarity to other oxidoreductase proteins, and expression of FRO1 in yeast conferred increased Fe(III)-chelate reductase activity. Furthermore, FRO1 mRNA levels in plants correlated with ...


The Shca Protein Is A Molecular Chaperone That Assists In The Secretion Of The Hoppsya Effector From The Type Iii (Hrp) Protein Secretion System Of Pseudomonas Syringae, Karin V. Van Dijk, Vincent C. Tam, Angela R. Records, Tanja Petnicki-Ocwieja, James R. Alfano Mar 2002

The Shca Protein Is A Molecular Chaperone That Assists In The Secretion Of The Hoppsya Effector From The Type Iii (Hrp) Protein Secretion System Of Pseudomonas Syringae, Karin V. Van Dijk, Vincent C. Tam, Angela R. Records, Tanja Petnicki-Ocwieja, James R. Alfano

Faculty Publications from the Center for Plant Science Innovation

Pseudomonas syringae uses a type III protein secretion system encoded by the Hrp pathogenicity island (Pai) to translocate effector proteins into plant cells. One of these effector proteins is HopPsyA. A small open reading frame (ORF), named shcA, precedes the hopPsyA gene in the Hrp Pai of P. s. syringae 61. The predicted amino acid sequence of shcA shares general characteristics with chaperones used in type III protein secretion systems of animal pathogens. A functionally non-polar deletion of shcA in P. s. syringae 61 resulted in the loss of detectable HopPsyA in supernatant fractions, consistent with ShcA acting as a ...


Photosynthesis And Shoot Health Of Five Birch And Four Alder Taxa After Drought And Flooding, William R. Graves, Mark A. Kroggel, Mark P. Widrlechner Mar 2002

Photosynthesis And Shoot Health Of Five Birch And Four Alder Taxa After Drought And Flooding, William R. Graves, Mark A. Kroggel, Mark P. Widrlechner

Horticulture Publications

Selection of under-used taxa of birches (Betula L.) and alders (Alnus Miller) for use in managed landscapes can be guided by information on their responses to moisture extremes in the root zone. Our objective was to compare the photosynthesis, leaf surface area, and subjective health ratings of eight relatively obscure birches and alders when treated with drought and flooding in a greenhouse. We also treated ‘Whitespire Sr.’ birch (Betula populifolia) to demonstrate responses of a cultivar common in the nursery trade. Plants used as controls were irrigated daily, whereas pots of flooded plants were immersed. All water was withheld from ...


Characteristics Of Trees According To Community Population Level And By Land Use In The U.S. Midwest., Valasia Iakovoglou, Janette R. Thompson, C. Lee Burras Mar 2002

Characteristics Of Trees According To Community Population Level And By Land Use In The U.S. Midwest., Valasia Iakovoglou, Janette R. Thompson, C. Lee Burras

Agronomy Publications

Long-term urban tree growth is crucial because of the need for tree-derived benefits and high placement costs. This study was conducted in five U.S. midwestern states to examine how tree characteristics are related to community population level and land-use type. Age, height, diameter, and average growth rates for the last decade were measured on 328 trees. When evaluated in terms of community population, trees in rural parks were older than trees in small, medium, and large towns. Adjusted mean growth rate was lower in rural parks than in small, medium, and large towns. When evaluated in terms of land ...


Crop Updates 2002 - Weeds, Vanessa Stewart, Alexander Douglas, Peter Newman, Glen Adams, Andrew Blake, Natalie Lauritsen, Sally Peltzer, Paul Matson, Abul Hasham, Nerys Wilkins, David Minkey, Glen Riethmuller, Tim Cusack, Kathryn Steadman, Pippa Michael, Paul Blackwell, Dave Brindal, Glen Adam, Michael Walsh, Wayne Parker, Clinton Revell, Giles Glasson, Dean Thomas, Alister Draper, Bill Roy, Marta Monjardin, David Pannell, Stephen Powles, Robert Barrett-Lennard, Martin Bent, Paul Neve, Art Diggle, Patrick Smith, Mechelle Owen, Abul Hashem, Christopher Preston, Tracey Gillam, Rick Llewellyn, Richard Quinlan, Aik Cheam, Siew Lee, Mike Clarke, David Nicholson, Harmoohinder S. Dhammu, Terry Piper, Chad Sayer, Ian Rose, Andrew Blake, Jerome Critch, Gordon R. Cumming, Sam Taylor, John Moore, Rosyln Jettner, Stuart Bee, Lionel Martin, Keith Devenish, Felicity Flugge, Amir Abadi, Duncan Peter, Stuart Mcalpine Feb 2002

Crop Updates 2002 - Weeds, Vanessa Stewart, Alexander Douglas, Peter Newman, Glen Adams, Andrew Blake, Natalie Lauritsen, Sally Peltzer, Paul Matson, Abul Hasham, Nerys Wilkins, David Minkey, Glen Riethmuller, Tim Cusack, Kathryn Steadman, Pippa Michael, Paul Blackwell, Dave Brindal, Glen Adam, Michael Walsh, Wayne Parker, Clinton Revell, Giles Glasson, Dean Thomas, Alister Draper, Bill Roy, Marta Monjardin, David Pannell, Stephen Powles, Robert Barrett-Lennard, Martin Bent, Paul Neve, Art Diggle, Patrick Smith, Mechelle Owen, Abul Hashem, Christopher Preston, Tracey Gillam, Rick Llewellyn, Richard Quinlan, Aik Cheam, Siew Lee, Mike Clarke, David Nicholson, Harmoohinder S. Dhammu, Terry Piper, Chad Sayer, Ian Rose, Andrew Blake, Jerome Critch, Gordon R. Cumming, Sam Taylor, John Moore, Rosyln Jettner, Stuart Bee, Lionel Martin, Keith Devenish, Felicity Flugge, Amir Abadi, Duncan Peter, Stuart Mcalpine

Crop Updates

This session covers fifty eight papers from different authors:

1. INTRODUCTION Vanessa Stewart, DEPARTMENT OF AGRICULTURE

INTEGRATED WEED MANAGEMENT

IWM system studies / demonstration sites

2. Major outcomes from IWM demonstration sites, Alexandra Douglas Department of Agriculture

3. Integrated weed management: Katanning, Alexandra Douglas Department of Agriculture

4. Integrated weed management: Merredin, Vanessa Stewart Department of Agriculture

5. Long term resistance site: Get ryegrass numbers low and keep them low! Peter Newman and Glen Adams Department of Agriculture

6. Using pastures to manage ryegrass populations, Andrew Blake and Natalie Lauritsen Department of Agriculture

Weed biology and competition

7. Understanding the weed ...


Crop Updates 2002 - Lupins, Amelia Mclarty, Bob French, Laurie Wahlsten, Martin Harries, Paul Blackwell, Mike Collins, Bill Crabtree, Geoff Fosbery, Angie Roe, Matt Beckett, Abul Hashem, Nerys Wilkins, Geoff Thomas, Ken Adcock, Debbie Thackray, Jenny Hawkes, Roger Jones, Brenda Coutts, Manisha Shankar, Mark Sweetingham, Bevan Buirchell, Nichole Burges, Dominie Wright, Susan J. Barker, Jairo A. Palta, Neil C. Turner, Matt Evans, Brett Glencross, John Curnow, Wayne Hawkins, Jon C. Clements Feb 2002

Crop Updates 2002 - Lupins, Amelia Mclarty, Bob French, Laurie Wahlsten, Martin Harries, Paul Blackwell, Mike Collins, Bill Crabtree, Geoff Fosbery, Angie Roe, Matt Beckett, Abul Hashem, Nerys Wilkins, Geoff Thomas, Ken Adcock, Debbie Thackray, Jenny Hawkes, Roger Jones, Brenda Coutts, Manisha Shankar, Mark Sweetingham, Bevan Buirchell, Nichole Burges, Dominie Wright, Susan J. Barker, Jairo A. Palta, Neil C. Turner, Matt Evans, Brett Glencross, John Curnow, Wayne Hawkins, Jon C. Clements

Crop Updates

This session covers twenty four papers from different authors:

LUPIN INDUSTRY ISSUES AND RESEARCH DIRECTIONS

ACKNOWLEDGMENTS Amelia McLarty LUPIN CONVENOR DEPARTMENT OF AGRICULTURE

VARIETIES

1. Evaluation of lupinus mutabilis in Western Australia, Bob French, Laurie Wahlsten and Martin Harries, Department of Agriculture

2. Adaption of restricted-branching lupins in short-growing season environments, Bob French, Laurie Wahlsten, Department of Agriculture

ESTABLISHMENT

3. Moisture delving for better lupin establishment, Dr Paul Blackwell, Department of Agriculture

4. Lupins, tramlines, 600mm rows, rolling and shield spraying … a good result in a dry season! Paul Blackwell and Mike Collins, Department of Agriculture

5. Lupin wider row ...


Genomewide Identification Of Pseudomonas Syringae Pv.Tomato Dc3000 Promoters Controlled By The Hrpl Alternative Sigma Factor, Derrick E. Fouts, Robert B. Abramovitch, James R. Alfano, Angela M. Baldo, C. Robin Buell, Samuel Cartinhour, Arn K. Chatterjee, Mark D'Ascenzo, Michelle L. Gwinn, Sondra G. Lazarowitz, Na-Chun Lin, Gregory B. Martin, Amos H. Rehm, David J. Schneider, Karin V. Van Dijk, Xiaoyan Tang, Alan Collmer Feb 2002

Genomewide Identification Of Pseudomonas Syringae Pv.Tomato Dc3000 Promoters Controlled By The Hrpl Alternative Sigma Factor, Derrick E. Fouts, Robert B. Abramovitch, James R. Alfano, Angela M. Baldo, C. Robin Buell, Samuel Cartinhour, Arn K. Chatterjee, Mark D'Ascenzo, Michelle L. Gwinn, Sondra G. Lazarowitz, Na-Chun Lin, Gregory B. Martin, Amos H. Rehm, David J. Schneider, Karin V. Van Dijk, Xiaoyan Tang, Alan Collmer

Faculty Publications from the Center for Plant Science Innovation

The ability of Pseudomonas syringae pv. tomato DC3000 to parasitize tomato and Arabidopsis thaliana depends on genes activated by the HrpL alternative sigma factor. To support various functional genomic analyses of DC3000, and specifically, to identify genes involved in pathogenesis, we developed a draft sequence of DC3000 and used an iterative process involving computational and gene expression techniques to identify virulence-implicated genes downstream of HrpLresponsive promoters. Hypersensitive response and pathogenicity (Hrp) promoters are known to control genes encoding the Hrp (type III protein secretion) machinery and a few type III effector proteins in DC3000. This process involved (i) identification of ...


Galactose-Binding Lectin From The Seeds Of Champedak (Artocarpus Integer): Sequences Of Its Subunits And Interactions With Human Serum O-Glycosylated Glycoproteins, Onn Haji Hashim Jan 2002

Galactose-Binding Lectin From The Seeds Of Champedak (Artocarpus Integer): Sequences Of Its Subunits And Interactions With Human Serum O-Glycosylated Glycoproteins, Onn Haji Hashim

Onn Haji Hashim

Our group has previously reported the isolation, partial characterisation, and application of a Galbeta1-3GalNAc- and IgA1-reactive lectin from the seeds of champedak (Artocarpus integer). In the present study, we have subjected the purified lectin to reverse-phase high performance liquid chromatography and sequenced its subunits. Determination of the N-terminal sequence of the first 47 residues of the large subunit demonstrated at least 95% homology to the N-terminal sequence of the alpha chains of a few other galactose-binding Artocarpus lectins, The two smaller subunits of the lectin, each comprised of 21 amino acid residues, demonstrated minor sequence variability. Their sequences were generally ...


Compensation For Herbivory In Wild Sunflower: Response To Simulated Damage By The Head-Clipping Weevil, Diana Pilson, Karin L. Decker Jan 2002

Compensation For Herbivory In Wild Sunflower: Response To Simulated Damage By The Head-Clipping Weevil, Diana Pilson, Karin L. Decker

Diana Pilson Publications

Herbivore damage is generally detrimental to plant fitness, and the evolutionary response of plant populations to damage can involve either increased resistance or increased tolerance. While characters that contribute to resistance, such as secondary chemicals and trichomes, are relatively well understood, characters that contribute to a plant’s ability to tolerate damage have received much less attention. Using Helianthus annuus (wild sunflower) and simulated damage of Haplorhynchites aeneus (head-clipping weevil) as a model system, we examined morphological characters and developmental processes that contribute to compensatory ability. We performed a factorial experiment that included three levels of damage (none, the first ...


Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran Jan 2002

Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran

Journal of the Arkansas Academy of Science

We studied the effect of a late growing-season fire on the plant and foliar arthropod communities in a naturally occurring grassland. In central Arkansas, these grasslands are common on south-facing slopes where shallow soils and hot/dry weather conditions during the summer cannot support the growth of a forest community. Patches of grassland were burned in the autumn (4 November, late growing season), often the time of natural fires in Arkansas, and compared to unburned areas. Fire increased the biomass of forbs and decreased the biomass of grasses, although overall biomass was not different between treatments. Among the foliar arthropods ...


The P23 Protein Of Citrus Tristeza Virus Controls Asymmetrical Rna Accumulation, Satyanarayana Tatineni, Siddarame Gowda, Maria A. Ayllon, Maria R. Albiach-Marti, Shailaja Rabindran, William O. Dawson Jan 2002

The P23 Protein Of Citrus Tristeza Virus Controls Asymmetrical Rna Accumulation, Satyanarayana Tatineni, Siddarame Gowda, Maria A. Ayllon, Maria R. Albiach-Marti, Shailaja Rabindran, William O. Dawson

Papers in Plant Pathology

Citrus tristeza virus (CTV), a member of the Closteroviridae, has a 19.3-kb positive-stranded RNA genome that is organized into 12 open reading frames (ORFs) with the 10 3' genes expressed via a nested set of nine or ten 3'-coterminal subgenomic mRNAs (sgRNAs). Relatively large amounts of negative-stranded RNAs complementary to both genomic and sgRNAs accumulate in infected cells. As is characteristic of RNA viruses, wild-type CTV produced more positive than negative strands, with the plus-to-minus ratios of genomic and sgRNAs estimated at 10 to 20:1 and 40 to 50:1, respectively. However, a mutant with all of ...


Effects Of Excessive Nitrogen Deposition On Foliar Nutrient Dynamics, Nutrient Concentrations, And Nutrient Ratios In A Central Appalachian Hardwood Forest, Sarah Beth Burdette Jan 2002

Effects Of Excessive Nitrogen Deposition On Foliar Nutrient Dynamics, Nutrient Concentrations, And Nutrient Ratios In A Central Appalachian Hardwood Forest, Sarah Beth Burdette

Theses, Dissertations and Capstones

Many forested systems of the eastern US are becoming significantly nitrogen (N) saturated due to chronic N deposition from the atmosphere. Nitrogen saturation has the potential to alter important internal plant processes, such as nutrient cycling. While extensive research has been conducted on the responses of soil to N saturation, considerably less research has focused on the response of plant nutrient dynamics, nutrient concentrations, and nutrient ratios to excess N. Research was conducted on two watersheds at the Fernow Experimental Forest in West Virginia: WS3 (fertilized with ammonium sulfate annually since 1989) and WS7 (untreated control). Presenescent and senesced leaves ...


Identification And Characterization Of Proteins Expressed In The Nectar Of Ornamental Tobacco , Clay Jeremy Carter Jan 2002

Identification And Characterization Of Proteins Expressed In The Nectar Of Ornamental Tobacco , Clay Jeremy Carter

Retrospective Theses and Dissertations

A small set of proteins, termed Nectarins, are secreted into the nectar of ornamental tobacco (Nicotiana langsdorffii x Nicotiana sanderae). The most highly expressed protein, Nectarin I (29 kD monomer), was originally identified as a germin-like protein (GLP) of unknown function. This remarkably stable protein was later shown to possess manganese dependent superoxide dismutase activity. Hydrogen peroxide, the product of SOD activity, was found to accumulate in nectar at levels up to 4 mM. The promoter (1.2 kb) of the Nectarin I gene was fused to the reporter gene chloramphenicol acetyl transferase (CAT) and shown to be expressed in ...


Selected Soybean Plant Introductions With Partial Resistance To Sclerotinia Sclerotiorum, D. D. Hoffman, B. W. Diers, G. L. Hartman, C. D. Nickell, R. L. Nelson, W. L. Pedersen, E. R. Cober, George L. Graef, J. R. Steadman, C. R. Grau, B. D. Nelson, L. E. Del Rio, T. Helms, T. Anderson, V. Poysa, University Of Guelph, W. C. Stienstra Jan 2002

Selected Soybean Plant Introductions With Partial Resistance To Sclerotinia Sclerotiorum, D. D. Hoffman, B. W. Diers, G. L. Hartman, C. D. Nickell, R. L. Nelson, W. L. Pedersen, E. R. Cober, George L. Graef, J. R. Steadman, C. R. Grau, B. D. Nelson, L. E. Del Rio, T. Helms, T. Anderson, V. Poysa, University Of Guelph, W. C. Stienstra

Papers in Plant Pathology

Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is a major soybean (Glycine max) disease in north-central regions of the United States and throughout the world. Current sources of resistance to Sclerotinia stem rot express partial resistance, and are limited in number within soybean germ plasm. A total of 6,520 maturity group (MG) 0 to IV plant introductions (PIs) were evaluated for Sclerotinia stem rot resistance in the United States and Canada in small plots or in the greenhouse from 1995 to 1997. Selected PIs with the most resistance were evaluated for resistance in the United States and Canada in ...


Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox Jan 2002

Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox

Inquiry: The University of Arkansas Undergraduate Research Journal

In addition to having numerous applications as food flavorings and pharmaceuticals, terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by insects. Sequences of DNA encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicago truncatula leaves, were selected from an expressed sequence tag (EST) database. The eDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated with factors known to trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl ...


Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth Jan 2002

Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by chewing insects. Clones encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicagotruncatula leaves, were selected from an expressed sequence tag (EST) database. The cDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated by known factors that can trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl jasmonate (meJA) treatments, whereas salicylic acid (SA) and glucose oxidase (GOX) had ...


Greenhouse And Field Evaluation Of Biological Control Of Fusarium Head Blight On Durum Wheat, D. A. Schisler, N. I. Khan, Michael J. Boehm, P. J. Slininger Jan 2002

Greenhouse And Field Evaluation Of Biological Control Of Fusarium Head Blight On Durum Wheat, D. A. Schisler, N. I. Khan, Michael J. Boehm, P. J. Slininger

Papers in Plant Pathology

Fusarium head blight (FHB) is a devastating disease that causes extensive yield and quality losses to wheat and barley. In durum wheat, the pathogen-produced toxin deoxynivalenol (DON) is retained in semolina at ~50%, and the causal agent of FHB, Gibberella zeae, has a strong adverse effect on pasta color. Two bacteria and two yeast strains with known efficacy against G. zeae on hexaploid wheats were produced in liquid culture and assayed on two cultivars of durum wheat in greenhouse bioassays. All antagonists reduced FHB severity on cultivar Renville, and three of the four reduced severity on cultivar Ben, with Bacillus ...


Isoetes Toximontana (Isoetaceae), A New Quillwort With Green Megaspores From The Northern Cape Of South Africa, Lytton John Musselman, J. P. Roux Jan 2002

Isoetes Toximontana (Isoetaceae), A New Quillwort With Green Megaspores From The Northern Cape Of South Africa, Lytton John Musselman, J. P. Roux

Biological Sciences Faculty Publications

Isoetes toximontana is only the second quillwort reported from the Northern Cape region in South Africa. It occurs in shallow water on the Gifberg. Megaspores are uniformly tuberculate on the proximal surface; their distal surfaces may have occasional rugi along with bullae. They are olive green when dry. Microspores are brown and aculeate. Preliminary field studies suggest that an unexpected diversity of quillworts is found in this region.


Arbuscular Mycorrhizae Of Mojave Desert Plants, J. H. Titus, P. J. Titus, R. S. Nowak, S. D. Smith Jan 2002

Arbuscular Mycorrhizae Of Mojave Desert Plants, J. H. Titus, P. J. Titus, R. S. Nowak, S. D. Smith

Life Sciences Faculty Publications

Roots of 15 Mojave Desert plant species were assessed for arbuscular mycorrhizal (AM) colonization in spring and autumn 1999. Another 19 species were assessed in autumn only. Perennial species were AM colonized, whereas annual species contained very low levels of AM hyphae or were nonmycorrhizal. The nonnative tree Tamarix ramosissima was also nonmycorrhizal. Levels of hyphae changed over the season in 2 species, arbuscle levels increased in 1 species, and vesicles decreased in 7 species. Mycorrhizal inoculum potential (MIP) was assessed in the soils associated with spring-collected plants. All soils were found to contain MIP. MIP values were not correlated ...


Clone Size Of Andropogon Gerardii Vitman (Big Bluestem) At Konza Prairie, Kansas, Kathleen H. Keeler, Charles F. Williams, Linda S. Vescio Jan 2002

Clone Size Of Andropogon Gerardii Vitman (Big Bluestem) At Konza Prairie, Kansas, Kathleen H. Keeler, Charles F. Williams, Linda S. Vescio

Faculty Publications in the Biological Sciences

Clone size of plants of Andropogon gerardii from Konza Prairie Biological Station, Manhattan, Kansas was estimated from spatial patterns of genetic variation, using proteins detected by starch gel electrophoresis and DNA content (ploidy) measured by flow cytometry. Unique multi-locus protein banding patterns and differences in ploidy were used to exclude plants as members of the same clone. Individual clones averaged about 2 m in diameter and areas of prairie of 100 m2 were calculated to contain an average of 31.8 genetic individuals.


Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide Jan 2002

Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide

Agronomy & Horticulture -- Faculty Publications

Acquisition of metals such as iron, copper, and zinc by the yeast Saccharomyces cerevisiae is tightly regulated. High affinity uptake systems are induced under metal-limiting conditions to maintain an adequate supply of these essential nutrients. Low affinity uptake systems function when their substrates are in greater supply. The FET4 gene encodes a low affinity iron and copper uptake transporter. FET4 expression is regulated by several environmental factors. In this report, we describe the molecular mechanisms underlying this regulation. First, we found that FET4 expression is induced in iron-limited cells by the Aft1 iron-responsive transcriptional activator. Second, FET ...


Genetic Analysis Of Feed Quality And Seed Weight Of Sorghum Inbred Lines And Hybrids Using Analytical Methods And Nirs, C. Hicks, M. R. Tuinstra, Jeffrey F. Pedersen, F. E. Dowell, K. D. Kofoid Jan 2002

Genetic Analysis Of Feed Quality And Seed Weight Of Sorghum Inbred Lines And Hybrids Using Analytical Methods And Nirs, C. Hicks, M. R. Tuinstra, Jeffrey F. Pedersen, F. E. Dowell, K. D. Kofoid

Agronomy & Horticulture -- Faculty Publications

Eight lines of grain sorghum and their F1 hybrids were evaluated for contents of crude protein (CP), fat (FAT), and starch (STA); protein digestibility (PD); and in vitro dry matter disappearance (IVDMD). The effect of seed weight (SW) on these traits and the potential use of near infrared reflectance spectroscopy (NIRS) to predict them also were investigated. The male lines included three normal-seeded lines (TX2737, TX435, and P954063) and two largeseeded lines (PL-1 and Eastin1). The female lines included commonU.S. seed parent lines (Wheatland, Redlan, and SA3042). The lines and their hybrids were grown under dryland conditions at Kansas ...


Localization Of Expansin Expression During Adventitious And Lateral Rooting In Response To Auxin In Loblolly Pine, Fuyu Xu Jan 2002

Localization Of Expansin Expression During Adventitious And Lateral Rooting In Response To Auxin In Loblolly Pine, Fuyu Xu

Electronic Theses and Dissertations

Loblolly Pine is the most important and widely cultivated timber species in the southern United States. Due to its fast growth, it is extensively planted for lumber and pulpwood. Vegetative propagation will enhance gains from genetic improvement of tree species. Rooted-cutting is at present the most reliable non-somatic embryogenesis method for cloning specific genotypes. However, an abrupt decline of adventitious rooting capacity has hindered the application of vegetative propagation in loblolly pine. Unraveling the rooting mechanism may facilitate a way to overcome this barrier. Regulation of lateral and adventitious root formation by auxin has been demonstrated through the application of ...


Investigating The Relationship Between Cryptococcus Fagisuga And Fagus Grandifolia In Great Smoky Mountains National Park, Ashley B. Morris, Randall L. Small, Mitchell B. Cruzan Jan 2002

Investigating The Relationship Between Cryptococcus Fagisuga And Fagus Grandifolia In Great Smoky Mountains National Park, Ashley B. Morris, Randall L. Small, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Focuses on a study which investigated the relationship between Cryptococcus fagisuga and Fagus grandifolia in Great Smoky Mountains National Park. Potential for genetic resistance; Methods; Results and discussion.