Biology Commons^™

Arabidopsis Bhlh100 And Bhlh101 Control Iron Homeostasis Via A Fit-Independent Pathway, Alicia B. Sivitz, Victor Hermand, Catherine Curie, Grégory Vert

Dartmouth Scholarship

Iron deficiency induces a complex set of responses in plants, including developmental and physiological changes, to increase iron uptake from soil. In Arabidopsis, many transporters involved in the absorption and distribution of iron have been identified over the past decade. However, little is known about the signaling pathways and networks driving the various responses to low iron. Only the basic helix–loop–helix (bHLH) transcription factor FIT has been shown to control the expression of the root iron uptake machinery genes FRO2 and IRT1. Here, we characterize the biological role of two other iron-regulated transcription factors, bHLH100 and bHLH101, in iron homeostasis. …

Plant Calcium Content: Ready To Remodel, Jian Yang, Tracy Punshon, Mary Lou Guerinot, Kendal D. Hirschi

Dartmouth Scholarship

By identifying the relationship between calcium location in the plant cell and nutrient bioavailability, the plant characteristics leading to maximal calcium absorption by humans can be identified. Knowledge of plant cellular and molecular targets controlling calcium location in plants is emerging. These insights should allow for better strategies for increasing the nutritional content of foods. In particular, the use of preparation-free elemental imaging technologies such as synchrotron X-ray fluorescence (SXRF) microscopy in plant biology may allow researchers to understand the relationship between subcellular location and nutrient bioavailability. These approaches may lead to better strategies for altering the location of calcium …

Reproductive Characteristics Of A Populus Euphratica Population And Prospects For Its Restoration In China, Dechang Cao, Jingwen Li, Zhenying Huang, Carol C. Baskin, Jerry M. Baskin, Peng Hao, Weilei Zhou, Junqing Li

Biology Faculty Publications

Populus euphratica is a dominant tree in riparian ecosystems in arid areas of northwest China, but it fails to regenerate in these systems. This study evaluates causes for the failure of sexual and asexual regeneration of this species in the wild. P. euphratica disperses as many as 85743 seeds/m² during summer, and the seeds germinate to 92.0% in distilled water and to 60.8% on silt. However, very few seeds (3.6%) can germinate on unflooded soil. The seed-rain season is prolonged by temporal variability in seed dispersal among individuals, which ensures that seedling emergence can occur during favorable conditions (i.e., …

Tcp Transcription Factor, Branch Angle Defective 1 (Bad1), Is Required For Normal Tassel Branch Angle Formation In Maize, Fang Bai, Renata Reinheimer, Diego Durantini, Elizabeth Kellogg, Robert Schmidt

Biology Department Faculty Works

In grass inflorescences, a structure called the “pulvinus” is found between the inflorescence main stem and lateral branches. The size of the pulvinus affects the angle of the lateral branches that emerge from the main axis and therefore has a large impact on inflorescence architecture. Through EMS mutagenesis we have identified three complementation groups of recessive mutants in maize having defects in pulvinus formation. All mutants showed extremely acute tassel branch angles accompanied by a significant reduction in the size of the pulvinus compared with normal plants. Two of the complementation groups correspond to mutations in the previously identified genes, …

Invasional Interference Due To Similar Inter- And Intraspecific Competition Between Invaders May Affect Management, Emily S.J. Rauschert, Katriona Shea

Biological, Geological, and Environmental Faculty Publications

As the number of biological invasions increases, the potential for invader– invader interactions also rises. The effect of multiple invaders can be superadditive (invasional meltdown), additive, or subadditive (invasional interference); which of these situations occurs has critical implications for prioritization of management efforts. Carduus nutans and C. acanthoides, two congeneric invasive weeds, have a striking, segregated distribution in central Pennsylvania, USA. Possible hypotheses for this pattern include invasion history and chance, direct competition, or negative interactions mediated by other species, such as shared pollinators. To explore the role of resource competition in generating this pattern, we conducted three related experiments …

Five Nuclear Loci Resolve The Polyploid History Of Switchgrass (Panicum Virgatum L.) And Relatives, Jimmy Triplett, Yunjing Wang, Jinshun Zhong, Elizabeth Kellogg

Biology Department Faculty Works

Polyploidy poses challenges for phylogenetic reconstruction because of the need to identify and distinguish between homoeologous loci. This can be addressed by use of low copy nuclear markers. Panicum s.s. is a genus of about 100 species in the grass tribe Paniceae, subfamily Panicoideae, and is divided into five sections. Many of the species are known to be polyploids. The most well-known of the Panicum polyploids are switchgrass (Panicum virgatum) and common or Proso millet (P. miliaceum). Switchgrass is in section Virgata, along with P. tricholaenoides, P. amarum, and P. amarulum, whereas P. miliaceum is in sect. Panicum. We have …

Traversing Swanton Road, 9th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich

Lawrence University Honors Projects

Historical records from Lake Winnebago show minimal macrophyte growth; however, reports from recent years claim that macrophyte growth in some areas of the lake has reached nuisance levels. This study aimed to investigate the species of macrophytes present and their abundances in four near-shore locations, as well as measurements of multiple water quality conditions. Rake sampling was used to identify species and quantify their abundances and distributions. In addition, data were collected on light penetration, Secchi depths, and suspended algae chlorophyll concentrations at each site. These data from shallow near-shore sites reveal trends in changing water clarity and light penetration …

Traversing Swanton Road, 8th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Moss Mural, Chelsea Fredrikson

Senior Honors Projects

Moss Mural: Bridging the Arts and Sciences

Chelsea Fredrikson

Major: Fine Arts

Advisor: Robert Dilworth

Advisor Department: Fine Arts

Date 5-2012

Abstract

When we are young, in elementary school, we are encouraged to learn subjects together. Fine arts, science, math, and literature all work as one, and overlap to teach us valuable lessons and tools we can use as we grow. But as we become older school systems segregate subjects, forcing students to chose a direction. Do I have a creative mind, or a logical mind?

As an art student I’ve tried over the course of my college …

The Ecological Roles Of Podostemum Ceratophyllum And Cladophora In The Habitat And Dietary Preferences Of The Riverine Caddisfly Hydropsyche Simulans, Brenna Tinsley

Mahurin Honors College Capstone Experience/Thesis Projects

The net-spinning caddisfly Hydropsyche simulans can be a common inhabitant of shallow reaches in riverine systems, and is easily the most common hydropsychid in the upper Green River, Kentucky. This study was performed in summer 2011 and focused on two main questions: 1. Do the larvae of the riverine caddisflies H. simulans and Cheumatopsyche preferentially inhabit dense patches of P. ceratophyllum compared to bare substrates in the upper Green River?, and 2. Do larvae of H. simulans and Cheumatopsyche consume the filamentous alga Cladophora during the annual late summer algal bloom in the upper Green River? Densities of both hydropsychid …

Assessment Of Oxidative Stress Gene Expression In Brassicaceae Plant Species Using A Real-Time Pcr Method, Florestella Ruiz

Theses and Dissertations - UTB/UTPA

Many plant species in the Brassicaceae plant family possess the ability to accumulate heavy metals. One challenge in using these hyperaccumulator plants for phytoremediation is that they are slow growing and often have a low biomass. This is a limitation should they be utilized for phytoremediation. However, the mechanisms by which hyperaccumulators tolerate heavy metals are of interest as these characteristics can be engineered into a plant species that is more suited for use in phytoremediation. Therefore, modification of oxidative stress response (OSR) gene expression in Brassicaceae species has become of great interest. Oxidative stress gene induction in both non-accumulator …

Host Plant Use By Competing Acacia-Ants: Mutualists Monopolize While Parasites Share Hosts, Stefanie Kautz, Daniel J. Ballhorn, Johannes Kroiss, Steffen U. Pauls, Corrie S. Moreau, Sascha Eilmus, Erhard Strohm, Martin Heil

Biology Faculty Publications and Presentations

Protective ant-plant mutualisms that are exploited by non-defending parasitic ants represent prominent model systems for ecology and evolutionary biology. The mutualist Pseudomyrmex ferrugineus is an obligate plant-ant and fully depends on acacias for nesting space and food. The parasite Pseudomyrmex gracilis facultatively nests on acacias and uses host-derived food rewards but also external food sources. Integrative analyses of genetic microsatellite data, cuticular hydrocarbons and behavioral assays showed that an individual acacia might be inhabited by the workers of several P. gracilis queens, whereas one P. ferrugineus colony monopolizes one or more host trees. Despite these differences in social organization, neither …

Traversing Swanton Road, 7th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Trait Convergence And Plasticity Among Native And Invasive Species In Resource-Poor Environments, Rebecca E. Drenovsky, Albina Khasanova, Jeremy J. James

Biology

Premise of study: Functional trait comparisons provide a framework with which to assess invasion and invasion resistance. However, recent studies have found evidence for both trait convergence and divergence among coexisting dominant native and invasive species. Few studies have assessed how multiple stresses constrain trait values and plasticity, and no study has included direct measurements of nutrient conservation traits, which are critical to plants growing in low-resource environments. Methods: We evaluated how nutrient and water stresses affect growth and allocation, water potential and gas exchange, and nitrogen (N) allocation and use traits among a suite of six codominant species from …

Isolation And Biophysical Study Of Fruit Cuticles, Subhasish Chatterjee, Sayantani Sarkar, Julia Oktawiec, Zhantong Mao, Olivia Niitsoo, Ruth E. Stark

Publications and Research

The cuticle, a hydrophobic protective layer on the aerial parts of terrestrial plants, functions as a versatile defensive barrier to various biotic and abiotic stresses and also regulates water flow from the external environment.1 A biopolyester (cutin) and long-chain fatty acids (waxes) form the principal structural framework of the cuticle; the functional integrity of the cuticular layer depends on the outer 'epicuticular' layer as well as the blend consisting of the cutin biopolymer and 'intracuticular' waxes.2 Herein, we describe a comprehensive protocol to extract waxes exhaustively from commercial tomato (Solanum lycopersicum) fruit cuticles or to remove epicuticular and intracuticular waxes …

Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann

Biological Sciences

The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I …

Effects Of The Manipulation Of Aboveground Plant Diversity In Restoration Management On The Diversity Of Belowground Arthropod Assemblage, Claire E. Gilmore

College of Science and Health Theses and Dissertations

A missing element in restoring belowground soil systems to a relatively healthy state may lie in promoting microarthropod diversity. By contributing to healthy nutrient cycling and assisting in the breakdown of leaf litter a diverse microarthropod population helps improve the overall soil quality. My study evaluated how current restoration practices aimed at maintaining aboveground diversity affects belowground microarthropod populations. I examined how the aboveground manipulation of plant diversity in restoration management practices affects the hyperdiverse assemblage of belowground arthropod communities. Additionally, I examined the relationship between soil nutrient content and microarthropod diversity. This study was conducted within the boundaries of …

Computer Simulation And Mathematical Models Of The Noncentrosomal Plant Cortical Microtubule Cytoskeleton, Ezgi Can Eren, Natarajan Gautam, Ram Dixit

Biology Faculty Research

There is rising interest in modeling the noncentrosomal cortical microtubule cytoskeleton of plant cells, particularly its organization into ordered arrays and the mechanisms that facilitate this organization. In this review, we discuss quantitative models of this highly complex and dynamic structure both at a cellular and molecular level. We report differences in methodologies and assumptions of different models as well as their controversial results. Our review provides insights for future studies to resolve these controversies, in addition to underlining the common results between various models. We also highlight the need to compare the results from simulation and mathematical models with …

Evolution Of Plant Sucrose Uptake Transporters, Anke Reinders, Alicia B. Sivitz, John M. Ward

Dartmouth Scholarship

In angiosperms, sucrose uptake transporters (SUTs) have important functions especially in vascular tissue. Here we explore the evolutionary origins of SUTs by analysis of angiosperm SUTs and homologous transporters in a vascular early land plant, Selaginella moellendorffii, and a non-vascular plant, the bryophyte Physcomitrella patens, the charophyte algae Chlorokybus atmosphyticus, several red algae and fission yeast, Schizosaccharomyces pombe. Plant SUTs cluster into three types by phylogenetic analysis. Previous studies using angiosperms had shown that types I and II are localized to the plasma membrane while type III SUTs are associated with vacuolar membrane. SUT homologs were …

Single-Molecule Analysis Of The Microtubule Cross-Linking Protein Map65-1 Reveals A Molecular Mechanism For Contact-Angle-Dependent Microtubule Bundling, Amanda Tulin, Sheri Mcclerklin, Yue Huang, Ram Dixit

Biology Faculty Research

Bundling of microtubules (MTs) is critical for the formation of complex MT arrays. In land plants, the interphase cortical MTs form bundles specifically following shallow-angle encounters between them. To investigate how cells select particular MT contact angles for bundling, we used an in vitro reconstitution approach consisting of dynamic MTs and the MT-cross-linking protein MAP65-1. We found that MAP65-1 binds to MTs as monomers and inherently targets antiparallel MTs for bundling. Dwell-time analysis showed that the affinity of MAP65-1 for antiparallel overlapping MTs is about three times higher than its affinity for single MTs and parallel overlapping MTs. We also …

Herbivory Affects Patterns Of Plant Reproductive Effort And Seed Production, Natalie M. West

School of Biological Sciences: Dissertations, Theses, and Student Research

Insect herbivory can have a major influence on plant reproduction, and potentially drive selection for strategies that reduce or resist herbivore effects. I used a combination of field experiments and ecological modeling to examine how modifications in the patterns and timing of reproductive investment might ameliorate the consequences of herbivore damage for plant reproduction. I performed experiments to examine how changes in reproductive effort after apical damage and reduction of insect herbivory affected seed production in two thistles native to Nebraska. I then used field data to parameterize a life history model predicting the resource allocation among buds and size …

Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Coexistence Patterns Of Two Invasive Thistle Species, Carduus Nutans And C. Acanthoides, At Three Spatial Scales, Emily S.J. Rauschert, Katriona Shea, Ottar N. Bjørnstad

Biological, Geological, and Environmental Faculty Publications

To better understand the competitive processes involved in invasion by congeners, we examine coexistence patterns of two invasive species, Carduus nutans and C. acanthoides, at three spatial scales. A roadside survey of 5 × 5 km blocks in a previously identified overlap zone provided information about the regional scale. At smaller scales, we surveyed four fields of natural co-occurrence, quantifying the spatial patterns at the field scale by randomly placed 1 × 1 m quadrats and at the smallest scale by detailing plant position within the quadrats. The patterns observed are strikingly different at the different scales. At the regional …

The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Salve Regina University Tree Inventory And Management Plan 2012, Bartlett Tree Experts

Archives Books

The Bartlett Inventory Solutions Team from Bartlett Tree Experts conducted an inventory of trees on the campus of Salve Regina University in May 2012. The inventory included: identifying trees and attaching to each tree a tag with an assigned tag number; identifying the trees' condition, health, and vigor; recommending risk evaluations and removals of appropriate trees; recommending pruning, soil management, and pest management treatments to promote tree safety; health, appearance, and longevity; and mapping the trees using GPSr hardware and Geographic Information System (GIS) software.

This digital copy of the plan is redacted. Information about the estimated values of individual …

A Functional Trait Perspective On Plant Invasion, Rebecca E. Drenovsky, Brenda J. Grewell, Carla M. D'Antonio

Biology

Global environmental change will affect non-native plant invasions, with profound potential impacts on native plant populations, communities and ecosystems. In this context, we review plant functional traits, particularly those that drive invader abundance (invasiveness) and impacts, as well as the integration of these traitsacross multiple ecological scales, and as a basis for restoration and management.
We review the concepts and terminology surrounding functional traits and how functional traits influence processes at the individual level. We explore how phenotypic plasticity may lead to rapid evolution of novel traits facilitating invasiveness in changing environments and then oscale up' to evaluate the relative …

Investigation Of The Importance Of Rock Chemistry For Saxicolous Lichen Communities Of The New Idria Serpentinite Mass, San Benito County, California, Usa, N Rajakaruna, K Knudsen, A Fryday, R E. O’Del, N Pope, F C. Olday, S Woolhouse

Faculty Publications, Biological Sciences

Although several lichen inventories exist for European ultramafic sites, only four surveys of serpentine lichens for North America have been published to date. Of those, only one has been conducted in California. We conducted a survey of saxicolous lichens from ultramafic rocks (including nephrite, partially serpentinized peridotite, and serpentinite) and non-ultramafic rocks (including silica-carbonate, shale, and sandstone) at the New Idria serpentinite mass, San Benito County, California. X-ray Fluorescence Analysis of the rocks from which the lichens were collected revealed significant elemental differences between the ultramafic and non-ultramafic rocks for 26 of the 32 major and trace elements analyzed. We …

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.