Life Sciences Commons^™

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 …

Summaries Of Arkansas Cotton Research In Progress In 2001, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

Cotton yields in Arkansas increased steadily during the eighties, but in recent years there has been a leveling off. Of more significance, however, is that extreme year-to-year variability in yields has occurred in the last decade, which is a major point of concern with cotton producers. It has been suggested that this may be related to extreme weather conditions during the boll development period in July and August. Average maximum temperatures in the 2001 season were a few degrees above normal. Recent research in Arkansas has indicated that elevated night temperatures during boll development may be a major contributory factor …

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

Department of Agronomy and 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 Fe(III)-chelate reductase activity. Sites of FRO_{1 …}

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

Department of Agronomy and 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 …

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

Center for Plant Science Innovation: Faculty and Staff Publications

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 …

Crop Updates 2002 - Weeds, Vanessa Stewart, Peter Newman, Glenn Adam, Andrew Blake, Natalie Lauritsen, Sally Peltzer, Paul Matson, Nerys Wilkins, David Minkey, Glen Riethmuller, Tim Cusack, Kathryn Steadman, Pippa Michael, Paul Blackwell, Dave Brindal, 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. …

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 …

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

Center for Plant Science Innovation: Faculty and Staff Publications

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 …

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

Department of Plant Pathology: Faculty Publications

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 …

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

Department of Plant Pathology: Faculty Publications

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 the 3' genes …

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 two, …

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

Department of Plant Pathology: Faculty Publications

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 …

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

Life Sciences Faculty Research

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 …

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

Department of Agronomy and 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 State …

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

Department of Agronomy and 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 …

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.

2001 Wild Blueberry Csrees Project Reports, Alfred A. Bushway, Mary Ellen Camire, Kathy Davis-Dentici, Michael Dougherty, Kathleen Buzzard, Rodney J. Bushway, Kristi Crowe, Brian Perkins, Darrell W. Donahue, Frank Drummond, Judy Collins, Rose Mary Seymour, Maya Panangadan, Maribeth Haines, Heather Mclaughlin, S L. Annis, C S. Stubbs, John M. Smagula, Walter Litten, Karen Loennecker, Adam Nielsen, David E. Yarborough, Timothy M. Hess, John Jemison

Wild Blueberry Research Reports

The 2001 edition of the Wild Blueberry CSREES Progress Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:

1. Effect of Wild Blueberry Products on Oxidation in Meat Based Food Systems

2. Factors Affecting the Microbial and Pesticide Residues Levels on Wild Blueberries

3. Determination of Pesticide Residue Levels in Fresh and Processed Wild Blueberries

4. Separation of Maggot-Infested Wild Blueberries in the IQF Processing Line

5. Water Use of Wild Blueberries and the Impact of Plant Water …

Kinetic Properties Of Bifunctional 6-Phosphofructo-2-Kinase/Fructose-2,6-Bisphosphatase From Spinach Leaves, Jennifer E. Markham, Nicholas J. Kruger

Department of Biochemistry: Faculty Publications

A cDNA encoding 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase was isolated from a Spinacia oleracea leaf library and used to ex­press a recombinant enzyme in Escherichia coli and Spodoptera frugiperda cells. The insoluble protein expressed in E. coli was purified and used to raise antibodies. Western blot analysis of a protein extract from spinach leaf showed a single band of 90.8 kDa. Soluble protein was purified to homogeneity from S. frugiperda cells infected with recombinant baculovirus harboring the isolated cDNA. The soluble protein had a molecular mass of 320 kDa, estimated by gel filtration chromatography, and a subunit size of 90.8 kDa. The purified pro­tein …

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

School of Biological Sciences: Faculty Publications

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.

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.