Biology Commons^™

Ecophysiological Implications Of Low Lignin In Eastern Leatherwood (Dirca Palustris L.), Anna Cole, Kayla Marie Rigdon, D. Gordon Brown, Katharine Lora Cary

Biology Faculty Publications

Dirca palustris L. (eastern leatherwood) is an understory shrub found throughout much of eastern North America. Dirca palustris wood has a low concentration of lignin, which is a molecule that grants structural rigidity to cell walls. The branches of D. palustris are thus remarkably flexible, but their low lignin content could cause greater vulnerability to water stress. We examined the conductivity, vessel anatomy, and field water potential of D. palustris and conducted ecological surveys. The data showed that D. palustris was not experiencing substantial drought-induced dysfunction in the field, even during an exceptionally hot and dry summer. Its water potentials …

Effective Farm Management Promotes Native Amf And Benefit Organic Farming Systems, Pushpa Soti, Rupesh R. Kariyat, Alexis Racelis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Highlights

• Agricultural practices have significant influence on the AMF community dynamics.

• Soil nutrients regulate AMF spore abundance and diversity.

• Using grass cover crops can promote native AMF in farms.

Abstract

Using soil inoculants containing naturally occurring beneficial microorganisms has become a popular practice in sustainable agriculture. However, an understanding of the environmental variables that affect plant-microbe interactions and the benefit of using commercial inoculum is relatively sparse. To address this, we examined the efficiency of three different methods to inoculate AMF (Arbuscular Mycorrhizal Fungi) in organic vegetable farms in south Texas: cover cropping, application of farm-produced (indigenous) AMF inoculum, …

Investigating Plant Physiological Responses To Global Phylogenetic Diversity Of Glomeromycotina, David Z. Mowbray

Honors Undergraduate Theses

Arbuscular mycorrhizal (AM) fungi are ubiquitous symbionts of terrestrial plant species with associations predominantly characterized as mutualistic. In addition to well-documented enhancement of host growth response, more recent analyses have demonstrated the conferral of host benefits under numerous biotic and abiotic stressors. However, much of the established evidence originates from studies involving limited AM fungal diversity. Accordingly, this study sought to evaluate the potential effects of inoculation on plant host physiological traits within a growth chamber environment, investigate potential correlations between host trait responses, & assess the degree of phylogenetic signal observed in trait responses due to the presence of …

Alwan: Reef Monitoring With Citizen Science Methods Trainer's Manual, Denise Garcia, Reine Cabreira, Alexis Principe, Wilfredo Licuanan

De La Salle University Publishing House Publications (DLSU PH)

No abstract provided.

Molecular Regulation Of The Salicylic Acid Hormone Pathway In Plants Under Changing Environmental Conditions, Christina A. M. Rossi, Eric J. R. Marchetta, Jong Hum Kim, Christian Castroverde

Biology Faculty Publications

Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience. We especially highlight advances in the thermosensitive mechanisms underpinning SA-mediated immunity, including differential regulation of key transcription factors (e.g., CAMTAs, CBP60g, SARD1, bHLH059), selective protein–protein interactions of the SA receptor NPR1, and dynamic phase separation of the recently identified …

Sheep Ingestive Behavior And Tannin Selection In Pampa Grassland And Feedlot, Marina Terra Braga

Green Canyon Environmental Research Area, Logan Utah

The Pampa grassland biome has high plant biodiversity, some with significant secondary compound concentrations such as tannins. Tannin inclusion in ruminant diets may improve meat quality and productivity. However, voluntary intake of this phenolic compound can be a challenge. This dissertation includes three studies within this context. The first study documented whether sheep consume tannin-rich Desmodium incanum (DI), the most common Pampa herbaceous legume species. The second study evaluated how forage tannin and protein concentration influenced sheep feedlot feed selection and the diet affects performance parameters. The third study evaluated sheep feeding behavior in a Pampa native pasture, and how …

Seasonal Starch Allocation In Starry Stonewort (Nitellopsis Obtusa) Harvested From Lake Koronis, Mn, And Development Of Non-Chemical Management Recommendations, Alyssa M. Haram

All Graduate Theses, Dissertations, and Other Capstone Projects

Starry stonewort (Nitellopsis obtusa) (Desvaux in Loiseleur) J. Groves is an invasive macro alga that can take over entire water columns and outcompete native species. Previous research has quantified seasonal life history and phenology but there is no research quantifying carbohydrate allocation which was the aim for Chapter II. Management efforts to control Nitellopsis obtusa have been limited to stressing the thalli and have not been able to directly target the reproductive bulbils on larger scales. Smaller scale efforts such as the use of hand pulling can be used but hand pulling is not realistic for larger infestations. Chapter III …

Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang

Faculty Journal Articles

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, …

Modelling Pollinator And Nonpollinator Selection On Flower Colour Variation, Brigitte Tenhumberg, Agnes S. Dellinger, Stacey D. Smith

School of Biological Sciences: Faculty Publications

1. Flower colour variation is ubiquitous within and between populations, which is why it has long been a focal point for studies of natural selection. This body of work has uncovered a wide range of selective agents, including pollinators, herbivores, and various abiotic factors. Nevertheless, we lack an integrative framework for predicting the phenotypic outcome in terms of floral pigmentation when these forces act collectively and often in opposition. 2. We here present such a framework through a model that incorporates selection on pigmentation at the vegetative phase (i.e., through survival to reproduction) and at the flowering phase (i.e., on …

Propagation, Physiology And Biomass Of Giant Cane (Arundinaria Gigantea) For Conservation And Restoration, Sanjeev Sharm

Graduate Theses/Dissertations

Giant cane (Arundinaria gigantea) is a native species to 22 states in the U.S. The species and its ecosystem are considered critically endangered, and the species has been reduced to 2% of its original extent. The species has a long cultural and conservation history. Large canebrakes were commonly found in Missouri in bottomland forests, stream and riverbanks, and margins of lakes. My research goals were to: 1) examine methods for propagation success from field to greenhouse to field; 2) examine the physiology of cane at one of the few current canebrakes, for greenhouse propagated plants, and field planted …

Variation In Establishment Success For American Mistletoe [Phoradendron Leucarpum (Raf.) Reveal & M.C. Johnst. (Viscaceae)] Appears Most Likely To Predict Its Distribution In Virginia And North Carolina, United States, Nicholas P. Flanders, Christopher P. Randle, Eric L. Walters, Lytton J. Musselman

Biological Sciences Faculty Publications

Dispersal limitation and variation in habitat suitability may determine an association of American mistletoe [Phoradendron leucarpum (Raf.) Reveal & M.C. Johnst. (Viscaceae)] with forested wetlands in Virginia and North Carolina, United States. Here, we first tested the alternative hypothesis that variation in host availability drives this habitat relationship. We used a generalized linear model to show a positive effect of forested wetland habitat on American mistletoe occurrence after accounting for both variation in host availability and differences among regions in host use. We then used seed sowing experiments to quantify how light availability and flood regime determine the viability …

Of Transcription Factor And Transformation: Elucidating Gene Function In The Common Ice Plant, Mesembryanthemum Crystallinum, Chinenye Lilian Izuegbunam

Dissertations and Theses

Abiotic stresses negatively affect plant growth and development across the globe, which also affect the production of food, feed, biofuel, and fiber to meet the demands of a growing population. Thus, developing novel strategies to increase abiotic stress tolerance in crops is necessary. One of these strategies is exploring transcription factors (TFs) in Crassulacean Acid Metabolism (CAM) plants to improve plant abiotic stress tolerances. Therefore, the first objective of this dissertation determine the abiotic stress tolerance function of a CAM TF, McHB7opt in Arabidopsis. This study found that McHB7opt increased stress-responsive pathways related to seed germination and early seedling development. …

Buoyancy And Emergence In Elymus Species, Sandor Jakab

Williams Honors College, Honors Research Projects

It is important that native plants are able to successfully emerge in wetlands because they play an important role in maintaining diversity. The relationship between seed buoyancy and seedling emergence was analyzed for three wetland species of the same genus: Elymus canadensis (FACU), Elymus macgregorii (FACW), and Elymus virginicus (FACW). E. macgregorii seemed to be the most buoyant, and E. virginicus and E. canadensis demonstrated very similar, less buoyant levels. Based on the idea that more buoyant seeds will be deposited at a shallow depth, and less buoyant seeds will be deposited at a deeper soil level, a relationship between …

Effect Of Soil Transplantation On Fungal Communities During Restoration, Thomas Luehl

All Master's Theses

Ectomycorrhizal fungi are integral parts of natural ecological systems that provide access to nutrients that would otherwise be unavailable by forming symbiotic relationships with plants. Relationships with ectomycorrhizal fungi are known to improve plant growth rate, increase plant resistance to pathogens, and improve survival. Current revegetation practices often ignore this relationship between fungi and plants. During the revegetation of the Interstate 90 Keechelus Lake wildlife overcrossing (Easton, WA), soil from forest sites adjacent to the restoration area were collected and used to inoculate a set of experimental plots to determine whether ectomycorrhizal fungi would become established in the plots and …

Ascophyllum Nodosum Seaweed Extract Application As A Possible Mechanism For Mitigating Salt Stress In Soybeans (Glycine Max), Elena Hoang

Honors Program Theses

Soil salinity, an abiotic stressor associated with climate change effects, inhibits the normal growth and development of sensitive crop species. The excessive accumulation of salt ions in plant tissue induces oxidative stress, which is characterized by an increased production of reactive oxygen species (ROS) damaging plant organelles and disrupting normal metabolic functions. Seaweed extracts (SWE) may be a solution for mitigating the effects of salt stress on crop yield and quality, as they introduce bioactive ingredients that are able to regulate gene expression and enhance natural physiological processes in plants. However, the positive benefits of SWE applications differ between plant …

A Cladoxylopsid With Complex Vascular Architecture From The Early Devonian Battery Point Formation (Québec, Canada), Jessica Chu

Cal Poly Humboldt theses and projects

Cladoxylopsids are seed-free plants that formed the world’s earliest forests and gave rise to horsetails (sphenopsids), but their evolutionary origins are poorly understood. Here, I describe a new Early Devonian cladoxylopsid from the Emsian (400-395 Ma) Battery Point Formation (Québec, Canada). The structural features of this plant indicate taxonomic affinity to cladoxylalean cladoxylopsids and its phylogenetic position supports placement in genus Cladoxylon (the proposed name, Cladoxylon kespekianum sp. nov., to be formalized by peer-reviewed publication). Specimens of this plant are permineralized in calcium carbonate and were studied using the acetate peel technique with light and electron microscopy. Cladoxylon kespekianum is …

Assessing The Recovery Of Forest Understory Vegetation After Clearcut Logging Across A 445-Year Chronosequence, Molly Smith Metok

Cal Poly Humboldt theses and projects

The conversion of natural forested lands to managed forests has reduced the amount of older, structurally diverse forests worldwide. In conifer forests of the Pacific Northwest (USA) – where the understory plant communities comprise only 1% of forest biomass but represent 90% of the plant species richness – the long-term impacts of timber harvesting are not fully understood. I used a chronosequence of forests in southwestern Oregon that ranged from 25 to 445 years of age to compare changes in plant communities in logged (i.e., managed) stands with that of stands in late succession and old growth conditions. The chronosequence …

Novel Mechanistic Insight Into Ciliary Regulation: Old Pathways Yield New Mechanisms, Larissa L. Dougherty

Dartmouth College Ph.D Dissertations

Cilia are structures present on most eukaryotic cells which provide important signaling and motile components to cells from early development to fully differentiated and matured cells. Regulation of these structures is critical to proper functioning of the cell and is known to be tied to the cell cycle. Preparation for ciliary assembly following cell cycle exit and ciliary disassembly following cell cycle reentry requires components throughout the cell body and within the cilium to facilitate this process. Here I identify how the cell adapts to ensure modifications to cilia occur for assembly or disassembly using the model organism Chlamydomonas reinhardtii. …

Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 1, Peter-Jon A. Waddell, Paul Galloway

Technical Bulletins

This technical bulletin defines and maps the land resources of the southern Goldfields region of Western Australia (WA). The southern Goldfields region, as featured in this bulletin, covers 151,753 km². The western and eastern borders are variable because they align with various cadastral boundaries. The western survey border, which in part follows the WA State Barrier Fence, demarcates cleared agricultural land from the intact, western extent of the Great Western Woodlands. The eastern border abuts the westernmost Nullarbor pastoral lease boundaries, except for the north-easternmost and south-easternmost edges which continue into Crown land. Major towns are Coolgardie, Kalgoorlie …

Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 2, Peter-Jon A. Waddell, Paul Galloway

Technical Bulletins

This technical bulletin defines and maps the land resources of the southern Goldfields region of Western Australia (WA). The southern Goldfields region, as featured in this bulletin, covers 151,753 km². The western and eastern borders are variable because they align with various cadastral boundaries. The western survey border, which in part follows the WA State Barrier Fence, demarcates cleared agricultural land from the intact, western extent of the Great Western Woodlands. The eastern border abuts the westernmost Nullarbor pastoral lease boundaries, except for the north-easternmost and south-easternmost edges which continue into Crown land. Major towns are Coolgardie, Kalgoorlie …

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …

Investigating The Effects Of Disturbance And Competition On Establishment, Growth, And Reproduction Of The Endangered Ripariosida Hermaphrodita, Daniel Engelking

Theses and Dissertations (Comprehensive)

Ripariosida hermaphrodita (Virginia Mallow) is a perennial riparian plant with broad, maple-like leaves. It grows up to three meters high and is often found in large clonal patches, but sexually reproduces readily. While this plant may seem like a redoubtable competitor when growing in large colonies, it is declining across its range in North America. The only known occurrences in Canada are in southern Ontario. Prior to this study, no new populations had been recorded even though one of the known populations produces copious amounts of viable seed with potential to disperse. There are many hypotheses for its rarity, but …

Natural Variation In Temperature-Modulated Immunity To Pseudomonas Syringae Pv. Tomato (Pst Dc3000) In Arabidopsis Thaliana Plants, Christina A. M. Rossi

Theses and Dissertations (Comprehensive)

Studies conducted on the model plant-pathogen system Arabidopsis thaliana-Pseudomonas syringae pv. tomato (Pst) showed that elevated temperature suppresses the pathogen-induced production of salicylic acid (SA), which is a key plant defence hormone. This increased host vulnerability at higher temperatures is due to downregulated expression of CALMODULIN BINDING PROTEIN 60-LIKE G (CBP60g) and SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1 (SARD1), which encode master regulators of SA production. Collectively, these previous studies only focused on one natural accession of Arabidopsis called Columbia-0 (Col-0). However, the intraspecific variation in Arabidopsis immunity phenotypes under elevated temperature remains unknown. To fill this critical knowledge gap, my …

An Automatic System To Evaluate Bait Station Visitation By Brown Treesnakes And Mongooses, Robert T. Sugihara, William C. Pitt, Are R. Berentsen, Francis L. Benevides Jr.

Human–Wildlife Interactions

Understanding the temporal, spatial, and behavioral patterns of the free-ranging target species in response to candidate baits and baiting strategies is important to ensure control success. This information can also assist in the development and deployment of feeding stations and can exclude non-target species while constituting effective bait delivery and control strategies for certain invasive animals, especially at environmentally sensitive sites. We used passive integrated transponder (PIT) tags in conjunction with very-high frequency radio-telemetry to remotely record bait station visitations and evaluate bait attractiveness in separate field research studies of brown treesnakes (Boiga irregularis) on Andersen Air Force …

Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species, Patrick Strzalkowski

Theses and Dissertations (Comprehensive)

The vast majority of the research into the performance of stormwater management ponds (SWMPs) has been performed in warm regions or during the warmer seasons in temperate regions. It is presumed that SWMPs are inactive in the winter as any potential stormwater is trapped in snow and ice. The main goal of this thesis was to test this presumption and to study the dynamics and performance of three SWMPs during the winter. Remote water level loggers were installed into the three SWMPs and daily grab samples from the influents and effluents were taken and analyzed for total phosphorus (TP), chloride, …

Macrolichen Inventory Of The Horse Mountain Botanical Area, Six Rivers National Forest, California, Usa, Sarah Norvell Conway

Cal Poly Humboldt theses and projects

Macrolichen diversity and community composition was determined for an area of high botanical interest in the Coast Ranges of Northern California – the Horse Mountain Botanical Area (HMBA) in Six Rivers National Forest. The Coast Ranges have been suggested to have high epiphytic macrolichen diversity, yet detailed site-specific macrolichen surveys are lacking for the area. Here we present comprehensive data on macrolichens of the HMBA integrated with environmental metadata at the landscape level. Twenty 0.4 ha sampling plots were positioned across the varying habitats of the HMBA and macrolichens were intensively sampled from all substrata. Out of 888 total collections, …

Are Epicuticular Waxes A Surface Defense Comparable To Trichomes? A Test Using Two Solanum Species And A Specialist Herbivore., Sakshi Watts, Rupesh R. Kariyat

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Although plants possess a suite of structural defenses, most studies have focused on trichomes. Trichomes can have both pre- and post-ingestive effects and have been consistently found to reduce herbivory. Along with trichomes, a few studies have focused on epicuticular waxes as an important defense; however, manipulated comparisons examining herbivore growth and development is limited. In this study, using two Solanum species (Solanum glaucescens and Solanum macrocarpon) that vary in both defenses, we tested the hypothesis that variation in defenses will affect herbivore feeding, primarily by restricting feeding commencement. We used electron microscopy together with a series of plant- and …

Investigation Of The Function Of Protein Acyl Transferases Using Crispr-Cas9 To Create Null Mutants, Claire E. Christopher

Honors Theses and Capstones

24 Protein Acyl Transferases (PATs) have been identified in the model organism Arabidopsis thaliana. Despite knowing the enzymatic function of these genes (palmitoylation), the specific subcellular pathways, protein targets, and cellular activities of these proteins remain unknown. To investigate the pathways that PAT genes are involved in, deletion mutations were created in several genes and the phenotype of the organisms carrying homozygous mutations was observed. To introduce mutations, the CRISPR/Cas9 system was inserted into the plant’s genome using Agrobacterium tumefaciens to cause deletions in PAT genes of interest. To date, no CRISPR-induced pat mutants have a noticeable phenotype. These …

Phytochemical And Antibacterial Evaluations Of Chloroform Extract Of Mondia Whitei (Hook F) Skeels, Abdullahi Shehu, Ojochide Inikpi Egwemi, Olufunmilayo Adeola Ajayi, Abdulmumeen Amao Hamid

Tanzania Journal of Science

Mondia whitei, also known as Mondia, is an aromatic plant of Apocynaceae family. It is used as aphrodisiac, antidepressant, fertility medication and to improve appetite. The present study aimed to evaluate the phytochemical and antibacterial properties of the plant. The chloroform extract of M. whitei was screened for its antibacterial effects using agar diffusion method against five bacterial strains (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae and Salmonella typhi). The extract was active against S. typhi, K. pneumoniae and S. aureus at 400, 400 and 200 mg/mL, respectively. The antibacterial activity of the extract was observed in a dose-dependent …

Antibacterial Potency Of Allium Sativum, Psidium Guajava, Zingiber Officinale Roots Against The Food Poisoning Strains (Escherichia Coli 0157:H7 And Staphylococcus Aureus), Godfrey O. Mauti

Tanzania Journal of Science

Escherichia coli 0157:H7 and Staphylococcus aureus are notorious food poisoning bacteria of great effect on human health. This study determined the phytochemical constituents of ethanolic, vacuum liquid chromatography (VLC) filtrates of Allium sativum (garlic), Psidium guajava (guava), Zingiber officinale (ginger) and their antibacterial activities on E. coli 0157:H7 and S. aureus. In a laboratory-based controlled experiment, the antibacterial and inhibitory activities of the VLC filtrates in doses of 0.01, 0.02, 0.04, and 0.08g/mL were investigated on E. coli 0157:H7 and S. aureus using the agar well diffusion method and compared with a standard antibiotic. The indices of the zone of …