Life Sciences Commons^™

Lake Mead National Recreation Area Vegetation Monitoring And Management: Quarterly Progress Report, Period Ending December 31, 2005, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Required reports on sticky buckwheat (Eriogonum viscidulum) and threecorner milkvetch (Astragalus geyeri var. triquetrus) to be submitted through appropriate protocols by December 30, 2005
• Summary report on several other rare plants to be submitted through appropriate protocols by December 30, 2005
• Invasive perennial pepperweed (also called tall whitetop; Lepidium latifolium) documented and treated by Weed Sentry within Black Canyon, Lake Mojave

Ecological Costs And Benefits Of Defenses In Nectar, Lynn S. Adler, Rebecca E. Irwin

Dartmouth Scholarship

The nectar of many plant species contains defensive compounds that have been hypothesized to benefit plants through a variety of mechanisms. However, the relationship between nectar defenses and plant fitness has not been established for any species. We experimentally manipulated gelsemine, the principal alkaloid of Carolina jessamine (Gelsemium sempervirens), in nectar to determine its effect on pollinator visitation, nectar robber visitation, and male and female plant reproduction. We found that nectar robbers and most pollinators probed fewer flowers and spent less time per flower on plants with high compared to low nectar alkaloids. High alkaloids decreased the donation of fluorescent …

Plant Controls Of Terrestrial Trace Gas Fluxes: Legumes, Microbes, Co And Hydrogen, Gary M. King

University of Maine Office of Research Administration: Grant Reports

This research seeks to determine the role of plant-microbe interactions on the production and fate of key trace gases in the atmosphere, particularly carbon monoxide (CO) and hydrogen (H2). Recent observations have revealed that the roots of all plants produce CO, and that the roots of nitrogen-fixing plants (Fabacae, commonly legumes) produce large amounts of both CO and H2. Production of these gases provides the basis for an interaction of plant roots with soil microbes that oxidize CO and H2. Field and greenhouse studies will involve a variety of cultivated and non-cultivated legumes and other plant taxa. Experimental analyses will …

First Report Of Crown And Stem Rot Of Orchid (Orchis Palustris) Caused By Sclerotinia Minor, C. Eken, S. Ercişli, A. Eşitken, E. Demirci, G. Y. Yuen

Department of Plant Pathology: Faculty Publications

Orchis palustris Jacq. is a wild orchid native to wetlands in eastern Anatolia. During June of 2003, near Erzurum, Turkey, a decline of this orchid was observed in several meadows that had been irrigated for forage production. Stems were chlorotic, wilted, and collapsed. There was a soft, watery rot at the crowns and lower stems. White mycelium and black sclerotia formed on necrotic stem and crown tissues. The fungus was isolated from sclerotia on potato dextrose agar (PDA) and identified as Sclerotinia minor Jagger on the basis of small sclerotia (0.5 to 2.5 mm long) scattered throughout the colonies (2). …

Mutagenesis Of Β-1,3-Glucanase Genes In Lysobacter Enzymogenes Strain C3 Results In Reduced Biological Control Activity Toward Bipolaris Leaf Spot Of Tall Fescue And Pythium Damping-Off Of Sugar Beet, Jeffrey D. Palumbo, Gary Y. Yuen, C. Christine Jochum, Kristin Tatum, Donald Y. Kobayashi

Department of Plant Pathology: Faculty Publications

Lysobacter enzymogenes produces extracellular lytic enzymes capable of degrading the cell walls of fungi and oomycetes. Many of these enzymes, including β-1,3-glucanases, are thought to contribute to the biological control activity expressed by several strains of the species. L. enzymogenes strain C3 produces multiple extracellular β-1,3-glucanases encoded by the gluA, gluB, and gluC genes. Analysis of the genes indicates they are homologous to previously characterized genes in the related strain N4-7, each sharing >95% amino acid sequence identity to their respective counterparts. The gluA and gluC gene products encode enzymes belonging to family 16 glycosyl …

Pseudomonas Syringae Type Iii Chaperones Shco1, Shcs1, And Shcs2 Facilitate Translocation Of Their Cognate Effectors And Can Substitute For Each Other In The Secretion Of Hopo1-1, Ming Guo, Scott T. Chancey, Fang Tian, Zhengxiang Ge, Yashitola Jamir, James R. Alfano

Center for Plant Science Innovation: Faculty and Staff Publications

The Pseudomonas syringae type III secretion system (TTSS) translocates effector proteins into plant cells. Several P. syringae effectors require accessory proteins called type III chaperones (TTCs) to be secreted via the TTSS. We characterized the hopO1-1, hopS1, and hopS2 operons in P. syringae pv. tomato DC3000; these operons encode three homologous TTCs, ShcO1, ShcS1, and ShcS2. ShcO1, ShcS1, and ShcS2 facilitated the type III secretion and/or translocation of their cognate effectors HopO1-1, HopS1, and HopS2, respectively. ShcO1 and HopO1-1 interacted with each other in yeast two-hybrid and coimmunoprecipitation assays. Interestingly, ShcS1 and ShcS2 were capable of substituting for …

Methods For Obtaining And Analyzing Whole Chloroplast Genome Sequences, Robert K. Jansen, Linda A. Raubeson, Jeffrey L. Boore, Claude W. Depamphilis, Timothy W. Chumley, Rosemarie C. Haberle, Stacia K. Wyman, Andrew J. Alverson, Riannon Peery, Sallie J. Herman, H. Matthew Fourcade, Jennifer V. Kuehl, Joel R. Mcneal, James Leebens-Mack, Liying Cui

All Faculty Scholarship for the College of the Sciences

During the past decade there has been a rapid increase in our understanding of plastid genome organization and evolution due to the availability of many new completely sequenced genomes. Currently there are 43 complete genomes published and ongoing projects are likely to increase this sampling to nearly 200 genomes during the next five years. Several groups of researchers including ours have been developing new techniques for gathering and analyzing entire plastid genome sequences and details of these developments are summarized in this chapter. The most important recent developments that enhance our ability to generate whole chloroplast genome sequences involve the …

Proposed Guidelines For A Unified Nomenclature And Phylogenetic Analysis Of Type Iii Hop Effector Proteins In The Plant Pathogen Pseudomonas Syringae, Magdalen Lindeberg, John Stavrinides, Jeffrey H. Chang, James R. Alfano, Alan Collmer, Jeffrey L. Dangl, Jean T. Greenberg, John W. Mansfield, David S. Guttman

Department of Plant Pathology: Faculty Publications

Pathovars of Pseudomonas syringae interact with their plant hosts via the action of Hrp outer protein (Hop) effector proteins, injected into plant cells by the type III secretion system (TTSS). Recent availability of complete genome sequences for a number of P. syringae pathovars has led to a significant increase in the rate of effector discovery. However, lack of a systematic nomenclature has resulted in multiple names being assigned to the same Hop, unrelated Hops designated by the same alphabetic character, and failure of name choices to reflect consistent standards of experimental confirmation or phylogenetic relatedness. Therefore, specific experimental and bioinformatic …

Crop Updates 2005 - Farming Systems, David Stephens, Nicola Telcik, Ross Kingwell, Wayne Pluske, Bill Bowden, Mike Collins, Frances Hoyle, D. V. Murphy, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Bill Crabtree, Geoff Anderson, Darren Kidson, Ross Brennan, Nick Drew, Craig Scanlan, Lisa Sherriff, Bob French, Reg Lunt, Jeff Russell, Angie Roe, Ian Maling, Matthew Adams, George Yan, Mohammad Hamza, Glen Riethmuller, Wal Anderson, Angela Loi, Phil Nichols, Clinton Revell, David Ferris, Phil Ward, Andrea Hills, Sally-Anne Penny, David Hall, Michael Robertson, Don Gaydon, Tress Walmsley, Caroline Peek, Megan Abrahams, Paul Raper, Richard O'Donnell, Trevor Lacey, Meredith Fairbanks, David Tennant, Cameron Weeks, Richard Quinlan, Alexandra Edward, Chris Carter, Doug Hamilton, Peter Tozer, Renaye Horne, Tracey Gianatti, Paul Carmody, Ian Foster, Michele John, Ross George, Imma Farré, Ian Kininmonth, Dennis Van Gool, Neil Coles, Bill Porter, Louise Barton, Richard Harper, Peter Ritson, Tony Beck, Chris Mitchell, Michael Hill, Fiona Barker-Reid, Will Gates, Ken Wilson, Rob Baigent, Ian Galbally, Mick Meyer, Ian Weeks, Traci Griffin, D. Rodriguez, M. Probust, M. Meyers, D. Chen, A. Bennett, W. Strong, R. Nussey, I Galbally, M. Howden

Crop Updates

This session covers forty four papers from different authors:

PLENARY

1. 2005 Outlook, David Stephens and Nicola Telcik, Department of Agriculture

FERTILITY AND NUTRITION

2. The effect of higher nitrogen fertiliser prices on rotation and fertiliser strategies in cropping systems, Ross Kingwell, Department of Agriculture and University of Western Australia

3. Stubble management: The short and long term implications for crop nutrition and soil fertility, Wayne Pluske, Nutrient Management Systems and Bill Bowden, Department of Agriculture

4. Stubble management: The pros and cons of different methods, Bill Bowden, Department of Agriculture, Western Australia and Mike Collins, …

Crop Updates 2005 - Cereals, Darsham Sharma, Brenda Shackley, Mohammad Amjad, Christine M. Zaicou-Kunesch, Wal Anderson, D. Tennant, Steve Penny Jr, Ben Curtis, Veronika Reck, Richard Richards, Gavin Knell, Steve Curtin, David Sermon, Alan Bedggood, T. B. Biddulph, T. L. Setter, J. A. Plummer, D. J. Mares, H. Khabaz-Saberi, I. Waters, G. Mcdonald, Harmohinder Dhammu, David Nicholson, Chris Roberts, Stephen Loss, Ross Brennan, Kith Jayasena, Eddy Pol, Simon Teakle, R. Loughman, C. Beard, B. Paynter, K. Tanaka, G. Poulish, A. Smith, Paul Damon, Zed Rengel, Lionel Martin, Narelle Hill, Ron Mctaggart, Ray Tugwell, Geoff Thomas, Manisha Shankar, John Majewski, D. Foster, H. Golzar, J. Piotrowski, Rob Grima, Jeff Russell, Angie Roe, Vivien A. Vanstone, Sean J. Kelly, Helen F. Hunter, Mena C. Gilchrist, C. R. Newman, Svetlana Micic, Phil Michael, Gabrielle Coupland, Ern Kostas, Mohammed Hamza, Tina Botwright Acuña, Len Wade, Ingrid Richardson

Crop Updates

This session covers thirty six papers from different authors:

WHEAT AGRONOMY

1. Optimum sowing time of new wheat varieties in Western Australia, Darshan Sharma, Brenda Shackley, Mohammad Amjad, Christine M. Zaicou-Kunesch and Wal Anderson, Department of Agriculture

2. Wheat varieties updated in ‘Flowering Calculator’: A model predicting flowering time, B. Shackley, D. Tennant, D. Sharma and C.M. Zaicou-Kunesch, Department of Agriculture

3. Plant populations for wheat varieties, Christine M. Zaicou-Kunesch, Wal Anderson, Darshan Sharma, Brenda Shackley and Mohammad Amjad, Department of Agriculture

4. New wheat cultivars response to fertiliser nitrogen in four major agricultural regions of Western Australia, Mohammad Amjad, …

Bloodroot Pollination: Bet-Hedging In Uncertain Times, W. John Hayden

Biology Faculty Publications

“Hurry up and wait.” The phrase that epitomizes life in the military or any other large, bureaucratic, organization, applies surprisingly well to bloodroot and similar ephemeral wildflowers. Each year these plants race to flower as early as possible to assure sufficient time for fruits to ripen and seeds to mature while sunshine is abundant at the forest floor, for all too soon the forest floor will be draped in shadows cast by the trees’ leafy canopy. Ephemerals do everything quickly: sprout, grow, flower, disperse seeds, and re-enter dormancy. But flowering in very early spring can be risky. Some days will …

Mutual Interference Between Genomic Rna Replication And Subgenomic Mrna Transcription In Brome Mosaic Virus, Valery Z. Grdzelishvili, Hernan Garcia-Ruiz, Tokiko Watanabe, Paul Ahlquist

Department of Plant Pathology: Faculty Publications

Replication by many positive-strand RNA viruses includes genomic RNA amplification and subgenomic mRNA (sgRNA) transcription. For brome mosaic virus (BMV), both processes occur in virus-induced, membrane- associated compartments, require BMV replication factors 1a and 2a, and use negative-strand RNA3 as a template for genomic RNA3 and sgRNA syntheses. To begin elucidating their relations, we examined the interaction of RNA3 replication and sgRNA transcription in Saccharomyces cerevisiae expressing 1a and 2a, which support the full RNA3 replication cycle. Blocking sgRNA transcription stimulated RNA3 replication by up to 350%, implying that sgRNA transcription inhibits RNA3 replication. Such inhibition was independent of the …

The Hrpk Operon Of Pseudomonas Syringae Pv. Tomato Dc3000 Encodes Two Proteins Secreted By The Type Iii (Hrp) Protein Secretion System: Hopb1 And Hrpk, A Putative Type Iii Translocator, Tanja Petnicki-Ocwieja, Karin V. Van Dijk, James R. Alfano

Center for Plant Science Innovation: Faculty and Staff Publications

Pseudomonas syringae is a gram-negative bacterial plant pathogen that is dependent on a type III protein secretion system (TTSS) and the effector proteins it translocates into plant cells for pathogenicity. The P. syringae TTSS is encoded by hrp-hrc genes that reside in a central region of a pathogenicity island (Pai). Flanking one side of this Pai is the exchangeable effector locus (EEL). We characterized the transcriptional expression of the open reading frames (ORFs) within the EEL of P. syringae pv. tomato DC3000. One of these ORFs, PSPTO1406 (hopB1) is expressed in the same transcriptional unit as hrpK. …

Morphogenesis In Germinating Fusarium Graminearum Macroconidia, Steven D. Harris

Department of Plant Pathology: Faculty Publications

Fusarium graminearum (teleomorph Gibberella zeae) is a significant pathogen of wheat and corn. F. graminearum forms multicellular macroconidia that play an important role in dissemination of the disease. The spatial pattern of morphogenesis in germinating macroconidia is described. Germ tubes preferentially emerge from the apical cells in a bipolar pattern that appears to be common to filamentous fungi. Chitin deposition occurs at two locations: the spore apices and cortical regions of macroconidial cells that subsequently produce a germ tube. The spatial pattern of morphogenesis requires the presence of functional microtubules, which may be responsible for the transport of key …

Flora Of The Gurvan Saykhan Mountains, Tseden Jamsran, Batlai Oyuntsetseg, Radnaakhand Tungalag

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Although two major books have been published on the Mongolian flora regional data are often still lacking due to the vast expanses of the country. Therefore we used published information and data from our own fieldwork to compile a relatively comprehensive inventory of the flora of the Gobi Gurvan Saykhan mountains in southern Mongolia.

Environmental Adaptations Of The Gobi Desert Plants In Mongolia: An Example Of C4-Plants, Ts. Tsendeekhuu, Clanton Candler Black

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This paper presents the results of our studies on the ecological adaptations and geographical distribution of plants with C4-photosynthesis in Mongolia using ¹³C isotope discrimination.

Previous studies identified about 80 C4-species in 8 families in the Mongolian flora. Our investigations lead to the identification of four additional species, which can be regarded as C4-plants. Orostachys spinosa (-16.26‰ ¹³C), O. thyrsiflora (-16.86‰ ¹³C), O. fimbriata (-16.15‰ ¹³C), and Euphorbia humifusa (-23.29‰ ¹³C). However, as the discrimination level for Euphorbia humifusa is very similar to that of C3-plants it may be switching between C3 and C4 types …

Reproductive Ecology Of Two Common Woody Species, Juniperus Sabina And Artemisia Santolinifolia, In Mountain Steppes Of Southern Mongolia, Katrin Ronnenberg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The present study describes the reproductive ecology of the prostrate shrub Juniperus sabina and the dwarf shrub Artemisia santolinifolia in dry mountain steppes of southern Mongolia. Whereas stands of the juniper are located at the drought limit of the genus’ distributional range, the genus Artemisia is typical of central Asian drylands. Both species produce large numbers of reproductive organs. For Juniperus sabina, however, only 2.5% of the morphologically intact seeds were found to be viable. Correspondingly, neither seedlings nor saplings were found in the field, and recruitment by reseeding happens at most rarely under the present climatic conditions.

Instead, …

2005 Virginia Wildflower Of The Year: Bloodroot, Sanguinaria Canadensis, W. John Hayden

Biology Faculty Publications

Bloodroot is an herbaceous perennial that grows from a persistent, branched underground stem or rhizome. Early each spring, while the forest canopy is still bare, each well-developed rhizome tip produces one leaf and one flower stalk. The leaf is kidney-shaped in its overall outline, but it is also divided into a pattern of rounded lobes and sinuses, rendering a complex overall shape. At flowering time, bloodroot leaves form a loose vertically-oriented collar around the flower stalk with the bluish-green lower leaf surface forming the outside of the collar; as the season progresses, the leaves open flat and expand to their …

The Glycosphingolipid Globotriaosylceramide In The Metastatic Transformation Of Colon Cancer, Olga Kovbasnjuk, Rakhilya Mourtazina, Boris Baibakov, Thomas Wang, Christian Elowsky, Michael A. Choti, Anne Kane, Mark Donowitz

Department of Plant Pathology: Faculty Publications

The most devastating aspect of cancer is the emergence of metastases. Thus, identification of potentially metastatic cells among a tumor cell population and the underlying molecular changes that switch cells to a metastatic state are among the most important issues in cancer biology. Here we show that, although normal human colonic epithelial cells lack the glycosphingolipid globotriaosylceramide (Gb₃), this molecule is highly expressed in metastatic colon cancer. In addition, a subpopulation of cells that are greatly enriched in Gb₃ and have an invasive phenotype was identified in human colon cancer cell lines. In epithelial cells in culture, …

The Role Of Peroxidases In The Development Of Plants And Their Responses To Abiotic Stresses., Deborah Vicuna

Doctoral

Peroxidases and its effects on plants were analysed. Peroxidases are involved in many physiological processes in plants, involving responses to biotic and abiotic stresses and the biosynthesis of lignin. Liglin is a polymer responsible for rendering the plant stronger and more rigid and also making the cell walls hydrophobic. Peroxidases are involved in the polymerization of the precursors of lignin. They are also involved in the scavenging of Reactive Oxygen Species (ROS), which are partially reduced forms of atmospheric oxygen, highly reactive, and capable of causing oxidative damage to the cell. Peroxidases can be a source of hydrogen peroxide (H2O2) …

Chlorella Virus Marburg Topoisomerase Ii: High Dna Cleavage Activity As A Characteristic Of Chlorella Virus Type Ii Enzymes, Jennifer S. Dickey, Tae-Jin Choi, James L. Van Etten, Neil Osheroff

Department of Plant Pathology: Faculty Publications

Although the formation of a covalent enzyme-cleaved DNA complex is a prerequisite for the essential functions of topoisomerase II, this reaction intermediate has the potential to destabilize the genome. Consequently, all known eukaryotic type II enzymes maintain this complex at a low steady-state level. Recently, however, a novel topoisomerase II was discovered in Paramecium bursaria chlorella virus-1 (PBCV-1) that has an exceptionally high DNA cleavage activity [Fortune et al. (2001) J. Biol. Chem. 276, 24401-24408]. If robust DNA cleavage is critical to the physiological functions of chlorella virus topoisomerase II, then this remarkable characteristic should be …

Review Of "Photosynthesis - Regulation Under Varying Light Regimes", Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This is a review of "Photosynthesis: Regulation Under Varying Light Regimes." By V S Rama Das. Enfield (New Hampshire): Science Publishers. $65.00. viii + 175 p; ill.; author and subject indexes. ISBN: 1-57808-343-5. 2004.

Effect Of Control Plot Density, Control Plot Arrangement, And Assumption Of Random Or Fixed Effects On Nonreplicated Experiments For Germplasm Screening Using Spatial Models, Boi Sebolai, Jeffrey F. Pedersen, D. B. Marx, D. L. Boykin

Department of Agronomy and Horticulture: Faculty Publications

Early generation selection experiments typically involve several hundred to thousands of lines. Various systematic and statistical techniques have been developed to increase effectiveness and efficiencies in such experiments, including the development and application of spatial statistical models. In this study, mixed model equations were used to provide least squares means (LSMEANs) and best linear unbiased predictors (BLUPs) and compare selection effectiveness and efficiencies to observed (Y) and true values in simulated experiments varying in size (10 X 10, 20 X 20 and 30 X 30 grids), control plots densities (0, 5, 10, 20, and 50%), control plot arrangements (high, medium, …

Variation In Isoprene Emission From Quercus Rubra: Sources, Causes, And Consequences For Estimating Fluxes, Jennifer L. Funk, Clive G. Jones, Dennis W. Gray, Heather L. Throop, Laura A. Hyatt, Manuel T. Lerdau

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoprene is the dominant volatile organic compound produced in many forest systems. Uncertainty in estimates of leaf level isoprene emission rate stems from an insufficient understanding of the patterns and processes controlling isoprene emission capacity in plant leaves. Previous studies suggest that variation in isoprene emission capacity is substantial; however, it is not known at what scale emission capacity is the most variable. Identifying the sources of variation in emission capacity has implications for conducting measurements and for model development, which will ultimately improve emission estimates and models of tropospheric chemistry. In addition, understanding the sources of variation will help …