Botany Commons^™

Arkansas Corn And Grain Sorghum Performance Tests 2014, R. D/ Bond, D. G. Dombek, J. A. Still

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.

South Loup River Valley Floristics: A Survey Of Selected Sites In Buffalo County, Nebraska, Steven J. Rothenberger, April M. Christman, Kevin Turek, Emmylou A. O'Brien

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Originating in the Nebraska Sand Hills, the South Loup River flows 30 km north of Kearney, Nebraska and traverses the northern edge of Buffalo County as it flows eastward to its confluence with the Middle Loup River in southwestern Howard County. Several diverse plant communities are associated with the South Loup Valley, including wet-meadows, wetland/oxbows, sand prairie, and riparian forest. Over a period of 6 years (2006-2012), we surveyed representative wet meadow, wetland, and sand prairie communities. We compiled an annotated vascular plant checklist that included 324 vascular plant species of which 11 were new county records. Three species of …

Perguson, Dee Carl, 1921-2010 (Sc 2861), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid only for Manuscripts Small Collection 2861. Letters of Ohio County, Kentucky native Dee Carl Perguson, written to Marjorie Clagett, his French teacher at Western Kentucky State Teachers College, during his World War II military service and afterward. He writes observantly of military life while training in Ohio, Georgia and Pennsylvania, of his experiences while serving in North Africa and Italy, and of his reassignment to Florida after suffering an arm wound. He also describes local plant life to Clagett, an accomplished amateur botanist. After the war, he writes from England during his postgraduate study. Settled in Seattle, Washington, …

Effects Of Genetic Modification Of Phosphoinositol Pathway On Light Signaling And Secondary Metabolism In Tomato Plants, Mohammad Alimohammadi

Theses and Dissertations

Inositol- (1,4,5) triphosphate (InsP3) is known as an important signaling factor and a regulator of plant responses to environmental and stress conditions. Overexpression of the InsP 5-ptase gene is found to enhance tolerance of transgenic tomato plants to abiotic stress and the induction of lycopene synthesis in InsP 5-ptase transgenic plants. Here, we demonstrated that the genetic reduction of InsP3 affected the overall phosphoinositol pathway, flavonoid metabolism, and light signaling in InsP 5-ptase transgenic plants. Transgenic plants that overexpress the InsP 5-ptase gene demonstrate an increase in the expression of major light signaling transcription factors (LeHY5, SIMYB12, LeELIP). We found …

Allopolyploidy, Diversification, And The Miocene Grassland Expansion, Matt Estep, Michael Mckain, Dilys Diaz, Jinshun Zhong, John Hodge, Trevor Hodkinson, Daniel Layton, Simon Malcomber, Rémy Pasquet, Elizabeth Kellogg

Biology Department Faculty Works

The role of polyploidy, particularly allopolyploidy, in plant diversification is a subject of debate. Whole-genome duplications precede the origins of many major clades (e.g., angiosperms, Brassicaceae, Poaceae), suggesting that polyploidy drives diversification. However, theoretical arguments and empirical studies suggest that polyploid lineages may actually have lower speciation rates and higher extinction rates than diploid lineages. We focus here on the grass tribe Andropogoneae, an economically and ecologically important group of C4 species with a high frequency of polyploids. A phylogeny was constructed for ca. 10% of the species of the clade, based on sequences of four concatenated low-copy nuclear loci. …

Leonard O. Marrow

Virginia Journal of Science

Obituary for Leonard O. Marrow who died August 24, 2014

Sfa Gardens Newsletter, Fall 2014, Sfa Gardens, Stephen F. Austin State University

SFA Gardens Newsletters

No abstract provided.

A Molecular Framework Phylogeny For Ptilotus (Amaranthaceae), Timothy A. Hammer

Biological Sciences Theses & Dissertations

Ptilotus (Amaranthaceae) is an Australian genus with over 100 species, most of which occur in arid Western Australia. Ptilotus has been a taxonomically difficult genus; despite rigorous morphological studies into the genus over many years, previous workers have found it difficult to delimit infrageneric groups due to inconsistent morphological variation. With the goal to establish a phylogenetic framework for the genus, 100 taxa were sampled, including 87 Ptilotus spp., and the ITS nrDNA and matK cpDNA were sequenced. The phylogeny was reconstructed using Bayesian, maximum likelihood and maximum parsimony analyses on separate and concatenated datasets. Morphological characters were assessed and …

Population Differentiation, Dispersal Limitation, And Local Adaptation In The Gametophytic Fern Vittaria Appalachiana, Sally M. Stevens

Open Access Dissertations

Species' distributions are driven by a variety of abiotic and biotic factors. As these factors become altered by global climate change, species are believed to respond to these projected environmental changes in four different ways. One response is the shifting of the species' geographic range to higher latitudes and elevations, which will be unlikely for those species that have limited dispersal potential. Alternatively, organisms may tolerate the change, which will be unlikely for those organisms that are not phenotypically plastic. A third potential response is to adapt to the new environment via rapid evolution, an unlikely response for those organisms …

Identification And Characterization Of Signal Components In Early Aba Signaling In Arabidopsis, Yueh-Ju Hou

Open Access Dissertations

The phytohormone abscisic acid (ABA) regulates growth, development, and response to abiotic stress in plants. The core ABA signaling has three key components: ABA receptors PYRABACTIN RESISTANCE 1 and PYR1-Like protein (PYR1/PYLs), type 2C protein phosphatases (PP2Cs) and SNF1- related protein Kinase 2s (SnRK2s). In the presence of ABA, PYR1/PYLs bind to and inhibit PP2Cs, leading to the release of SnRK2s from suppression, to activate downstream events such as ABA-responsive gene expression. To identify new components in the ABA signaling pathway, we performed a yeast two-hybrid screen for PYLs and SnRK2s interactors. We identified two proteins that interact with PYLs …

Identification And Characterization Of Factors Involved In Dna Demethylation And Anti-Silencing In Arabidopsis, Zhaobo Lang

Open Access Dissertations

DNA methylation is a key epigenetic mark for transcriptional gene silencing in many eukaryotes. DNA methylation status can be dynamically controlled by methylation and active demethylation processes. Compared to the well-known mechanisms of DNA methylation, the mechanisms of DNA demethylation and its regulation are poorly understood. In order to better understand the DNA demethylation pathway, we developed two genetic screening systems in Arabidopsis to identify new components involved in the DNA demethylation. In the first system, which is based on 35S promoter driven SUC2 (sucrose transporter 2) transgene, a mutant (91-1) was isolated and map-based cloning identified the …

Limited Alpine Climatic Warming And Modeled Phenology Advancement For Three Alpine Species In The Northeast United States, Michael L. Davis, Kenneth D. Kimball, Douglas M. Weihrauch, Georgia L. D. Murray, Kenneth Rancourt

Ecology Center Publications

• Premise of the study: Most alpine plants in the Northeast United States are perennial and flower early in the growing season, extending their limitedgrowing season. Concurrently, they risk the loss of reproductive efforts to late frosts. Quantifying long-term trends in northeastern alpine flower phenology and late-spring/early-summer frost risk is limited by a dearth of phenology and climate data, except for Mount Washington, New Hampshire (1916 m a.s.l.).
• Methods: Logistic phenology models for three northeastern US alpinespecies (Diapensia lapponica, Carex bigelowii and Vaccinium vitis-idaea) were developed from 4 yr (2008–2011) of phenology and air temperature measurements from 12 …

Spiranthes Lacera (Raf.) Raf., W. Mcclain

Specimens by Name

No abstract provided.

Phytochemical, Antioxidant And Antibacterialpotential Of Elaeagnus Kologa (Schlecht.) Leaf., Zoe Merculieff, Shubharani Ramnath, Seethalakshmi Madhukar Sankoli, Sivaram Venkataramegowda, Ganti S. Murthy, Ruben Michael Ceballos

Biological Sciences Faculty Publications and Presentations

Objective To screen different solvent extracts of Elaeagnus kologa (E. kologa) leaf to determine the phytochemicals, potent antioxidant and antibacterial activity to find out the possible source of applied pharmaceutical formulations. Methods Solvent extracts of leaf material were prepared using the Soxhlet apparatus. A study was performed on antioxidant activity of methanolic extract of leaf by 1-1-diphenyl-2-picrylhydrazyl method. The phenolic and flavonoid content of all the fractions were determined using high performance liquid chromatography. Leaves were also subjected to protein and carbohydrate test. Results The total phenols, flavonoids were found to be high in petroleum ether as compare to other …

Diatom Flora In Subterranean Ecosystems: A Review, Elisa Falasco, Luc Ector, Marco Isaia, Carlos E. Wetzel, Lucien Hoffmann, Francesca Bona

International Journal of Speleology

In scarcity of light and primary producers, subterranean ecosystems are generally extremely oligotrophic habitats, receiving poor supplies of degradable organic matter from the surface. Human direct impacts on cave ecosystems mainly derive from intensive tourism and recreational caving, causing important alterations to the whole subterranean environment. In particular, artificial lighting systems in show caves support the growth of autotrophic organisms (the so-called lampenflora), mainly composed of cyanobacteria, diatoms, chlorophytes, mosses and ferns producing exocellular polymeric substances (EPSs) made of polysaccharides, proteins, lipids and nucleic acids. This anionic EPSs matrix mediates to the intercellular communications and participates to the chemical …

Regulation Of Mor By Different Abiotic Stresses In Arabidopsis Thaliana, Luke Stepan, Rucha Karve, Anjali Iyer-Pascuzzi

The Summer Undergraduate Research Fellowship (SURF) Symposium

The climate is changing and as a consequence the environment is becoming hotter and drier. How different plants will react to these changes is unknown. Identification of genes involved in stress tolerance can help predict plant-environment interactions and lead to stress tolerant plants. The MOR gene (Modulator Of Root ROS, ROS = Reactive Oxygen Species) in the model plant Arabidopsis thaliana encodes a transcription factor that may regulate stress responses, as mor mutants are drought tolerant. We hypothesized that MOR expression changes in response to different abiotic stress stimuli. We tested MOR expression in response to salt (NaCl), abscisic acid …

Keys To The Families And Genera Of Vascular Plants In Northwestern California, James P. Smith Jr, John O. Sawyer Jr

Botanical Studies

No abstract provided.

Expression And Functional Characterization Of Mtp Genes From Arabidopsis Thaliana In Saccharomyces Cerevisiae, Yessica E. Cerino

Theses and Dissertations - UTB/UTPA

In this study the functional characterization and overexpression of Metal Tolerance Protein (MTP) cDNA were evaluated using a transgenic yeast (Saccharomyces cerevisiae) model system as a preliminary means for the characterization of metal tolerance conferred by putative Group III MTP genes from Arabidopsis thaliana. Metal disc assays for nickel, zinc, cobalt and cadmium treatments were performed to measure the tolerance imparted to yeast by the MTP cDNAs. Statistical analysis from zinc and cadmium assays showed AtMTP1 imparted the highest zinc tolerance in yeast, while AtMTPB1 imparted the highest cadmium and cobalt tolerance. However, AtMTPA2 and AtMTPB produced a decrease in …

Response Of Grassland Songbirds To Grazing System Type And Range Condition, Stephen K. Davis, Brenda C. Dale, Tom Harrison, David C. Duncan

The Prairie Naturalist

Much of the remaining prairie in Canada is grazed by cattle and most grassland birds of conservation concern occupy such habitat. Identifying vegetation features related to grassland bird habitat selection that can be easily understood and measured by professional range managers and livestock producers on private lands is an important step towards conserving and restoring remaining grasslands. We conducted grassland bird surveys on 28 native mixed-grass prairie pastures in southern Saskatchewan to determine whether grazing system type (season-long vs. rotational) influenced avian abundance. Grazing system had no influence on abundance of grassland passerines. Conservation agencies that promote particular grazing systems …

Legacy Effects In Prairie Restoration: A 73-Year Spatial History, Thomas D. Brock

The Prairie Naturalist

Black Earth Rettenmund Prairie State Natural Area, one of the highest quality prairie remnants in southern Wisconsin’s Driftless Area, has been the target of extensive restoration efforts since it was acquired by the Nature Conservancy (TNC) in 1986. In the present work, I analyzed the spatial history of this prairie using a Geographical Information System (GIS) and an extended series of air photos, on-the-ground surveys, early maps, and land-use records. In 1937, when the first air photo was taken, the site was nearly devoid of trees and shrubs. In subsequent years, the site became progressively woody until at the time …