Digital Commons Network^™

The Effects Of Water Stress On Datura Wrightii, Tony Festa, Kristin Lapointe, Sara Tandon

Featured Research

The Santa Monica Mountains are home to a unique Mediterranean type ecosystem. Due to the effects of global warming and human disruption, the native species are beginning to decrease in population. It is imperative to observe and study the native species in order to preserve the local plant and animal life. This project focuses on the native flower Datura wrightii, specifically the causes of the opening and closing of its flowers. For Datura wrightii to be pollinated, it must be open. The results of this project will help to educate the public on how to sustain an environment in which …

Critical Roles Of Rna-Binding Proteins In Mirna Biogenesis In Arabidopsis, Guodong Ren, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MicroRNAs (miRNAs) are key regulators of gene expression and play critical roles in modulating metabolism, development and physiology in animals and plants. miRNA levels are transcriptionally and post-transcriptionally controlled for their proper function. Recent studies have shown that RNA-binding proteins play important roles in producing miRNAs by affecting the accurate and/or efficient processing of precursors of miRNAs. Many of these RNA-binding proteins also have roles in general RNA metabolism, indicating potential connections between miRNA biogenesis and other RNA metabolism. Here, we focus on the function of several RNA-binding proteins in miRNA biogenesis in Arabidopsis.

Pseudomonas Syringae Catalases Are Collectively Required For Plant Pathogenesis, Ming Guo, Anna Block, Crystal D. Bryan, Donald F. Becker, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 must detoxify plant-produced hydrogen peroxide (H₂O₂) in order to survive in its host plant. Candidate enzymes for this detoxification include the monofunctional catalases KatB and KatE and the bifunctional catalase-peroxidase KatG of DC3000. This study shows that KatG is the major housekeeping catalase of DC3000 and provides protection against menadione-generated endogenous H₂O₂. In contrast, KatB rapidly and substantially accumulates in response to exogenous H₂O₂. Furthermore, KatB and KatG have nonredundant roles in detoxifying exogenous H₂O₂ and are …

Post-Transcriptional Control Of Mirna Abundance In Arabidopsis, Guodong Ren, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MicroRNAs (miRNAs) are a class of small non-coding RNAs (small RNAs) that are 20–24nt in length and predominantly repress gene expression at post-transcriptional levels. They regulate many biological processes including development, metabolism and physiology. Numerous studies have revealed that the steady-state levels of miRNA are under sophisticated control to ensure their proper function. In this review, we summarize recent advances on regulation of miRNA processing and stability in plants.

Uridylation Of Mirnas By Hen1 Suppressor1 In Arabidopsis, Guodong Ren, Xuemei Chen, Bin Yu

Center for Plant Science Innovation: Faculty Publications

HEN1-mediated 2′-O-methylation has been shown to be a key mechanism to protect plant microRNAs (miRNAs) and small interfering RNAs (siRNAs) as well as animal piwi-interacting RNAs (piRNAs) from degradation and 3′ terminal uridylation [1–8]. However, enzymes uridylating unmethylated miRNAs, siRNAs, or piRNAs in hen1 are unknown. In this study, a genetic screen identified a second-site mutation hen1 suppressor1-2 (heso1-2) that partially suppresses the morphological phenotypes of the hypomorphic hen1-2 allele and the null hen1-1 allele in Arabidopsis. HESO1 encodes a terminal nucleotidyl transferase that prefers to add untemplated uridine to the 3′ end of RNA, which is …

The Dna- And Rna-Binding Protein Factor Of Dna Methylation 1 Requires Xh Domain-Mediated Complex Formation For Its Function In Rna-Directed Dna Methylation, Meng Xie, Guodong Ren, Chi Zhang, Bin Yu

Center for Plant Science Innovation: Faculty Publications

Studies have identified a sub-group of SGS3-LIKE proteins including FDM1–5 and IDN2 as key components of RNA-directed DNA methylation pathway (RdDM). Although FDM1 and IDN2 bind RNAs with 5' overhangs, their functions in the RdDM pathway remain to be examined. Here we show that FDM1 interacts with itself and with IDN2. Gel filtration suggests that FDM1 may exist as a homodimer in a heterotetramer complex in vivo. The XH domain of FDM1 mediates the FDM1–FDM1 and FDM1–IDN2 interactions. Deletion of the XH domain disrupts FDM1 complex formation and results in loss-of-function of FDM1. These results demonstrate that XH domainmediated …

Botanist In Death Valley, Stanley L. Welsh

Books by Faculty of the Monte L. Bean Life Science Museum

Abstract

This book details the author’s trips to Death Valley, along with general ecological information about the region. Explorations by other natural historians are also recounted. Death Valley and its surrounding mountain ranges are stark and appear to lack vegetative cover, but that appearance is deceiving. The ranges and valley support a great diversity of living things, both plants and animals. Pages 10–17 contain photographs of various landscapes. Pages 18–20 list the plant species collected in Death Valley, 1970–1983. Voucher specimens are available for study at Stanley L. Welsh Herbarium, Brigham Young University.

Terrestrial Biosphere Models Need Better Representation Of Vegetation Phenology: Results From The North American Carbon Program Site Synthesis, Andrew D. Richardson, Ryan S. Anderson, M. Altaf Arain, Alan G. Barr, G. Bohrer, Guangsheng Chen, Jing M. Chen, Philippe Ciais, Kenneth J. Davis, Ankur R. Desai, Michael C. Dietze, Danilo Dragoni, Steven R. Garrity, Christopher M. Gough, Robert Grant, David Y. Hollinger, Hank A. Margolis, Harry Mccaughey, Mirco Migliavacca, Russell K. Monson, J. William Munger, Benjamin Poulter, Brett M. Raczka, Daniel M. Ricciuto, Alok K. Sahoo, Kevin Schaefer, Hanqin Tian, Rodrigo Vargas, Hans Verbeeck, Jingfeng Xiao, Yongkang Xue

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Phenology, by controlling the seasonal activity of vegetation on the land surface, plays a fundamental role in regulating photosynthesis and other ecosystem processes, as well as competitive interactions and feedbacks to the climate system. We conducted an analysis to evaluate the representation of phenology, and the associated seasonality of ecosystem- scale CO₂ exchange, in 14 models participating in the North American Carbon Program Site Synthesis. Model predictions were evaluated using long-term measurements (emphasizing the period 2000–2006) from 10 forested sites within the AmeriFlux and Fluxnet-Canada networks. In deciduous forests, almost all models consistently predicted that the growing season started …

Stanley L. Welsh Record Books: Botanical Collections, Stanley L. Welsh

Books by Faculty of the Monte L. Bean Life Science Museum

Abstract

This work attempts to present data available previously only in a set of bound field books in which location data was recorded along with numbers assigned to plant collections taken at the places cited. The record begins in 1953 and has been added to in all subsequent years including 2012. The records give indication of the species collected and of the localities where they were taken. Nomenclature has been updated in some instances where changes in names allow interpretation of early collections wherein names were derived from publications then out of date, but not in all instances. Especially not …

Creation Of A Natural History Information Database With Mobile Device Access For The Pace Campus In Pleasantville, Joshua J. Schwartz, Martina Blackwood

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.

Metabolic And Gene Expression Changes Triggered By Nitrogen Deprivation In The Photoautotrophically Grown Microalgae Chlamydomonas Reinhardtii And Coccomyxa Sp. C-169, Joseph Msanne, Di Xu, Anji Reddy Konda, J. Armando Casas-Mollano, Tala Awada, Edgar B. Cahoon, Heriberto Cerutti

Center for Plant Science Innovation: Faculty Publications

Microalgae are emerging as suitable feedstocks for renewable biofuel production. Characterizing the metabolic pathways involved in the biosynthesis of energy-rich compounds, such as lipids and carbohydrates, and the environmental factors influencing their accumulation is necessary to realize the full potential of these organisms as energy resources. The model green alga Chlamydomonas reinhardtii accumulates significant amounts of triacylglycerols (TAGs) under nitrogen starvation or salt stress in medium containing acetate. However, since cultivation of microalgae for biofuel production may need to rely on sunlight as the main source of energy for biomass synthesis, metabolic and gene expression changes occurring in Chlamydomonas and …

Influence Of The Neotyphodium--Tall Fescue Symbiosis On Belowground Processes, D. H. Mcnear Jr., Rebecca L. Mcculley

Plant and Soil Sciences Faculty Publications

Much of the work to date on the relationships between cool season grasses and Neotyphodium fungal endophytes has focused on the physiological, biochemical, and genetic ramifications of the host-fungus relationship and the subsequent influence these effects have on ruminant nutrition, plant adaptation to environmental stresses, and aboveground ecological processes. Relatively little attention has been paid to effects on belowground parameters. In this paper, we review the research evaluating the impact of one endophyte-grass association, the Neotyphodium – tall fescue symbiosis, on underground ecological and biogeochemical processes. We also present some preliminary data showing that the quantity and nature of tall …

Systematics, Biogeography And Leaf Anatomy And Architecture Of Bursera Subgen. Bursera (Burseraceae) In The Greater Antilles And The Bahamas, María Cristina Martínez-Habibe

CGU Theses & Dissertations

This dissertation presents a comprehensive study on the origin and evolutionary relationships of the species of Bursera in Cuba, Hispaniola, Jamaica and the Bahamas. The goals of the first chapter were to test monophyly of the group, revisit a recent transfer of two species of Bursera to Commiphora, and place recently discovered mainland species using the reconstructed phylogenies. Additionally, divergence estimations using fossils were used as independent tests of several hypotheses regarding the arrival of the modern biota to the Greater Antilles and Bahamas (GAB). I conclude that all endemic taxonomic entities of the genus in this region belong …

Stem Mechanical Strength In Thinned Versus Non-Thinned Ceanothus Spinosus, Ksp, David J. Kang, Hannah Y. Choe, Melinda L. Marchiano

Featured Research

What effect does the thinning of chaparral around building structures have on plant health? More specifically, does the thinning of Ceanothus spinosus influence mechanical strength? The ability of our native chaparral to withstand environmental factors, such as the Santa Ana winds, and overall health is directly related to plant strength. Seeking to answer these questions, we hypothesized that a difference in water potential between thinned and non-thinned chaparral affects the stem mechanical strength of the plants.We believed that thinned C. spinosus due to greater hydration will be mechanically stronger than non-thinned chaparral.The knowledge of what helps chaparral to be stronger …

The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn

Featured Research

Our project investigated the relationship between climate change and vegetation type conversion in the Santa Monica Mountains on north and south facing slopes. Our hypothesis is that with a shift in climate towards dryer, hotter, and longer summers, and shorter and dryer winters, we will see a shift in the density of native chaparral in the Santa Monica mountains, and possibly an influx of non-native species. We tested this hypothesis by choosing three study sites that were on north/south ridgelines to simulate a dryer, harsher climate (south) and a more temperate climate (north). Using the point-quarter method to measure the …

Exploring The Hydration Levels Of Malosma Laurina At Different Elevations On A Man-Made Trail, Eric S. Taylor, Brad J. Anderson, Brandon E. Stites

Featured Research

The purpose of this study is to examine the water potential of Malosma laurina at different elevations of a man made trail in the chapparal of the Santa Monica Mountains. Chaparral in the Santa Monica Mountains have been depleted because of human involvement effecting the chaparral ecosystem. Fire breaks and man made trails are a few of the major causes of the rapidly changing ecosystem and continues to cause stress among the plants. We are testing the effect that man made trails have on the water potential of Malosma laurina. This was measured by taking samples of Malosma laurina at …

A Comparison Of Water Potential And Mechanical Strength Of Tip And Base Leaves In Heteromeles Arbutifolia, Aaron Tsai, James Maynard

Featured Research

Heteromeles arbutifolia, commonly known as, Hollywood, is a plant that is extremely common in the California Chaparral ecosystem. It was observed that with Hollywood, the leaves grow on the tips of the branches predominantly. However, there are leaves that grow on the base of the branches that appear to be equally as healthy. The purpose of this investigation was to determine whether the leaves that grow at the tips of the branches or at the base of the branches were better suited to benefit the rest of the plant. Our hypothesis was that the leaves at the tips of the …

Mechanical Strength And Hydration Level Of Heteromeles Arbutifola And Eriogonium Cinerium, Erin Hayes, Allison Naasz, Ariel Mangum

Featured Research

The purpose of this study was to explore the hydration levels and mechanical strength of two species native to the same area: the dry Mediterranean region of the Santa Monica Mountains. The plants in this area must make adaptations to dry and arid climates, and We will compare how they stack up against each other in terms of drought resistance. Using Hollywood (heteromeles arbutifola) and Buckwheat (Eriogonium cinerium) we studied the different hydration levels and mechanical strengths and compared them. Both H. Arbutifola and the E. Cinerium are expected to mechanically stronger when hydrated.. We also expect the H. Arbutifola …

The Effect Of Historical Legacy On Adaptation: Do Closely Related Species Respond To The Environment In The Same Way?, Rachel Prunier, Kent E. Holsinger, Jane E. Carlson

EEB Articles

The many documented examples of parallel and convergent evolution in similar environments are strong evidence for the role of natural selection in the evolution of trait variation. However, species may respond to selection in different ways; idiosyncrasies of their evolutionary history may affect how different species respond to the same selective pressure. To determine whether evolutionary history affects trait-environment associations in a recently diverged lineage, we investigated within-species trait-environment associations in the white proteas, a closely related monophyletic group. We first used MANOVAs to determine the relative importance of shared response to selection, evolutionary history, and unique responses to selection …

Molecular And Biochemical Characterization Of Oleate- And Glycerol-3-Phosphate-Regulated Signaling In Plants, Mihir Kumar Mandal

Theses and Dissertations--Plant Pathology

Oleic acid (18:1), a monounsaturated fatty acid (FA), is synthesized upon desaturation of stearic acid (18:0) and this reaction is catalyzed by the plastidal enzyme stearoyl-acyl carrier protein-desaturase (SACPD). A mutation in the SSI2/FAB2 encoded SACPD lowers 18:1 levels, which correlates with induction of various resistance (R) genes and increased resistance to pathogens. Genetic and molecular studies have identified several suppressors of ssi2 which restore altered defense signaling either by normalizing 18:1 levels or by affecting function(s) of a downstream component. Characterization of one such ssi2 suppressor mutant showed that it is required downstream of low 18:1-mediated constitutive …

Characterization Of Sorghum Grain And Evaluation Of Sorghum Flour In A Chinese Egg Noodle System, Liman Liu, Thomas J. Herald, Donghai Wang, Jeff D. Wilson, Scott R. Bean, Fadi M. Aramouni

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Sorghum is a gluten free grain that has potential to be used as an alternative to wheat flour for the Celiac Sprue market. There are thousands of sorghum lines that have not been characterized for grain, flour or end product quality. The objective of the research was to gain an understanding among grain sorghum quality factors and Chinese egg noodles quality. Four sorghum hybrids were characterized and evaluated for kernel characteristics, proximate analysis, flour composition and end product in a Chinese egg noodle system. Kernel size and weight affected the flour particle size and the amount of starch damage. Flour …

Post-Biological Control Invasion Trajectory For Melaleuca Quinquenervia In A Seasonally Inundated Wetland, Philip W. Tipping, Melissa R. Martin, Ryan Pierce, Ted D. Center, Paul R. Pratt, Min B. Rayamajhi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The recruitment and mortality of Melaleuca quinquenervia seedlings were evaluated over a 3-year period in a seasonally inundated wetland in the western Everglades region. The mean (±SE) density of seedlings/ saplingsm^-1 declined from 64.8 (±4.5) to 0.5 (±0.2) over the 3 years, a population reduction of 99.2%. Four distinct water regimes characterized this site: dry, dry to wet transition, flooded, and wet to dry transition. Seedling recruitment was highest in the dry to wet transition and lowest in the flooded water regime, while mortality was highest under flooded and dry water regimes. The mean estimate of population growth (λ) …

Distribution Of Genes And Repetitive Elements In The Diabrotica Virgifera Virgifera Genome Estimated Using Bac Sequencing, Brad S. Coates, Analiza P. Alves, Haichuan Wang, Kimberly K. O. Walden, B. Wade French, Nicholas J. Miller, Craig A. Abel, Hugh M. Robertson, Thomas W. Sappington, Blair D. Siegfried

Department of Entomology: Faculty Publications

Feeding damage caused by the western corn rootworm, Diabrotica virgifera virgifera, is destructive to corn plants in North America and Europe where control remains challenging due to evolution of resistance to chemical and transgenic toxins. A BAC library, DvvBAC1, containing 109,486 clones with 104 ± 34.5 kb inserts was created, which has an ~4.56X genome coverage based upon a 2.58 Gb (2.80 pg) flow cytometry-estimated haploid genome size. Paired end sequencing of 1037 BAC inserts produced 1.17Mb of data (~0.05% genome coverage) and indicated ~9.4 and 16.0% of reads encode, respectively, endogenous genes and transposable elements (TEs). …

Osnabrück Botanical Expeditions To Mongolia, Barbara Neuffer, Nikolai Friesen, Batlai Oyuntsetseg, Tseden Jamsran, Herbert Hurka

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

Three botanical expeditions to Mongolia have been undertaken by the Botany Department of the University of Osnabrück in cooperation with the Botany Department of the National Mongolian University of Ulaanbaatar. The first expedition in 2000 took us to the Mongolian Altay, the second in 2001 to the Gobi and Gobi Altay, and the third in 2010 to East Mongolia including the Khingan Mts. (Numrug). In 2000, we were the first botanists being allowed to enter the border area between China and Russia in the Mongolian Altay since a long time, because this had been a prohibited area for decades. We …

Comparative Study Of Constituents Of Essential Oils Of Ocimum Basilicum L. Cultivated In The Mongolian Gobi, Shataryn Altantsetseg, Sandui Shatar, N. Javzmaa

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

The essential oils of the herb Ocimum basilicum L., cultivated in the Mongolian Gobi, have been examined. Oils were isolated by hydro-distillation and analyzed by GC-MS. The principle components of Common Basil were methyl chavicol (52.1 %), linalool (23.9 %). In the oils of the different varieties of Basil were the following compounds found: Sweet Basil: linalool (24.5–27.4 %), methyl chavicol (19.8–20.0 %), bergamotene (10.0 %), 1.8-cineole (8.5 %); Purple Basil: linalool (52.8 %), 1.8-cineole (8.7 %); Cinnamon Basil: methyl chavicol (60.4 %), 1.8-cine-ole (6.3 %), linalool (3.3 %) and cadinol (3.2 %); Italian large leaf Basil …

Diploid Allium Ramosum From East Mongolia: A Missing Link For The Origin Of The Crop Species A. Tuberosum?, Batlai Oyuntsetseg, Frank R. Blattner, Nikolai Friesen

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

In eastern Mongolia, a diploid close relative of the tetraploid (4x) crop species Allium tuberosum and its closest wild relative A. ramosum (4x) was found and characterized by karyotype analysis and with molecular marker techniques. An earlier analyses revealed A. ramosum to be sister of the crop but excluded it as its progenitor. At that time a putative diploid cytotype of A. ramosum was hypothesized as a potential progenitor taxon of the tetraploids. New phylogenetic analyses of chloroplast and nuclear DNA sequences including the recently found cytotype (A. aff. tuberosum) together with A. tuberosum and A. ramosum accessions …

Biochemical Research On Mongolian Lichens, Bryophytes And Vascular Plants – In Memoriam, Dr. Siegfried Huneck (1928–2011), Hans D. Knapp

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

Dr. Siegfried Huneck, biochemist and lichenologist from the Institute for Biochemistry of Plants in Halle/Saale, died on September 9, 2011. He was a world wide leading expert on lichen substances. An obituary with curriculum vitae and a complete list of publications was published by Stordeur et al. (2011)

Indicators Of Pasture Digression In Steppe Ecosystems Of Mongolia, Elena V. Danzhalova, S. N. Bazha, P. D. Gunin, Yu. I. Drobyshev, T. I. Kazantseva, A. V. Prischepa, N. N. Slemnev, E. Ariunbold

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

The research shows that widely used key measures of vegetation structure (species diversity, projected cover and above-ground phytomass) are not always suitable as indicators of pasture degradation. Based on an analysis above-ground phytomass composition, new quantitative indices are offered that give a more realistic picture of rangeland condition in Mongolia.

Structure And Productivity Of Haloxylon Ammodendron Communities In The Mongolian Gobi, Tamara I. Kazantseva, Nikolay N. Slemnev, Pjotr D. Gunin, Sh. Tsooj

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

Communities of Haloxylon ammodendron are widespread in the Mongolian Gobi where they play a significant role in biodiversity preservation. They occupy several main types of habitats, showing differences in density, projective cover, and productivity. Haloxylon ammodendron plays a similar, if not even more important role in the arid zone of Mongolia as the principal forest-making trees in the Northern part of the country. The complex set of quantitative parameters of Haloxylon ammodendron stands studied here in respect to temporal dynamics can serve as an indicator of both the vitality of desert ecosystems, and of environmental change.

Effect Of Nitrogen Fertilization On Net Nitrogen Mineralization In Grassland Soil Of Northern China: Implications For Grassland Management, X. Zhang, Q. Wang, Frank S. Gilliam, W. Bai, X. Han, L. Li

Biological Sciences Faculty Research

Nitrogen (N) applications can have a significant effect on soil N availability. The effect of 3 years of N fertilization on soil net N mineralization during the growing season (May–September) was studied in 2005 and 2006 in grassland of northern China. The experimental design was a randomized complete block with four replications of five rates of N addition as urea (0, 2, 4, 8 and 16 g N m⁻² year⁻¹). Results indicated that net N mineralization rate varied seasonally and between years, ranging from −0.04 to 0.52 μg g⁻¹ d⁻¹ in 2005 and from −0.09 …