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Propagation Of Wild-Collected Prunus Americana Marsh. By Rooted Cuttings For Germplasm Conservation In The Southern Appalachians, Hannah Leianne Nelms

Masters Theses and Doctoral Dissertations

American plum, Prunus americana Marsh., is a native tree valued for wildlife and wildland restoration. To propagate this tree for germplasm conservation, this study investigated the optimal season of collection and indole-3-butyric acid (IBA) treatment for a viable rooted stem-cutting method. Cuttings were collected from trees in eight locations in May, July, and September, treated with 0-ppm, 1000-ppm, 3000-ppm, or 8000-ppm IBA for five seconds, and held in a mist propagation bed with basal heat for four to six weeks. The results of this study show that (1) rooted cuttings are a viable propagation method for wild-collected American plum, (2) …

Sweet Potato In The Lower Rio Grande Valley: Evaluating Performance Across Several Cultivars, Jon Dale

Theses and Dissertations

In Texas’ subtropical, semiarid Lower Rio Grande Valley (LRGV), citrus and sugarcane cultures have dominated specialty crop production for more than a half-century. However, the future of these high-dollar crops is becoming uncertain with increases in exotic pathogens, intensifying urbanization and the overarching complexities of both climate change and binational governance of Rio Grande Basin waters. For these reasons, the region’s specialty crop sector needs to be ready for alternatives that could benefit both market outlets and reduced input dependencies. Sweet potato (Ipomoea batatas), commercially grown in various similar climates worldwide with limited water resources, could be one …

Study Of Population Dynamics Of Sugarcane Aphid (Melanaphis Sacchari) In Rio Grande Valley, Texas, Neetu Khanal

Theses and Dissertations

Chapter 1: This chapter incorporates detailed information about the biotype concept, aphids, their types and their biotypes, importance of studying insect biotypes and their role in mediating host plant defenses.

Chapter 2: This chapter explains in detail about the biology, biotypes, feeding behavior, damage, and economic loss caused due to sugarcane aphid infestation. This chapter further elaborates on the need for studying population level differences and justifies the objectives and significance of this research study.

Chapter 3: This chapter provides information about the comprehensive work done on three different populations of sugarcane aphid collected from three different locations in Rio …

A Programmatic Geographic Information Systems Analysis Of Plant Hardiness Zones, Andrew Bowen

Electronic Theses and Dissertations

The Plant Hardiness Zone Map consists of thirteen geographical zones that describe whether a plant can survive based on average annual minimal temperatures. As climate change progresses, minimum temperatures in all regions are expected to change. This work programmatically evaluates predicted future climate projection data and converts it to United States Department of Agriculture-defined hardiness zones. Through the next 80 years, hardiness zones are projected to move poleward; in effect, colder zones will lose area and warmer zones will gain area globally. Some implications include changes in crop growing degree days, which could alter crop productivity, migration and settlement of …

Management Of Nematodes Associated With Tobacco And Sweet Potato Using Non-Fumigant Approach, Md Shah Alam

All Theses

Tobacco and sweet potato are attacked by several species of plant-parasitic nematodes leading to substantial yield losses. Because host-plant resistance is lacking in commercial cultivars and other common methods of nematode management either have low efficacy or pose adverse effects to the environment, controlled environment studies were conducted to evaluate the efficacy of non-fumigant chemical and biological nematicides against Meloidogyne enterolobii on tobacco and Rotylenchulus reniformis on sweet potato. Results suggest that fluensulfone was the most effective in suppressing M. enterolobii in tobacco, followed by oxamyl and fluopyram. The biological Burkholderia derived biological nematicide did not suppress the nematode population. …

Influence Of Cover Crops On Soybean Yield And Partial Returns As An Alternative To Double-Crop Soybean In Arkansas, Drew Kirkpatrick, Trenton L. Roberts, Kris Brye, Jeremy Ross

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The number of hectares dedicated to winter wheat (Triticum aestivum L.) in the southern United States has been trending downward for almost a decade, presenting an opportunity for producers to utilize alternatives in their soybean [Glycine max (L.) Merr.] rotations, such as winter cover crops. A study was established to compare the cover crops to traditional cropping systems by determining the effect each had on a successive soybean crop and to examine partial economic returns. Cropping systems implemented were winter fallow, winter wheat, and seven cover crop treatments, including cereal rye (Secale cereale L.), black-seeded oat ( …

Meta-Analysis Of The Effects Of Endophytes And Their Secondary Metabolites On Herbivory From Insects, Derrick Taylor

All Theses

Endophyte-infected plants have reduced the level of herbivory. The defense to herbivory can vary due to the metabolites in the plant and the method of feeding from the pest. Secondary metabolites produced by the endophytes are mainly alkaloids. The associations between endophytes and some alkaloid groups are studied in greater detail. The lack of research of certain alkaloid groups ultimately means that some alkaloids had more data that could be analyzed. As a result, the alkaloid groups were not evenly represented in the meta-analysis. The meta-analysis analyzed the relative effectiveness of the metabolites or endophytes in each of the articles …

Laser Inscribed Graphene Aptasensor For Detection Of Apple Stem Pitting Virus, Yifan Tang

All Theses

Apple stem pitting virus (ASPV) is a latent RNA virus that could cause significant loss to apple production; early-stage field diagnosis could reduce the economic loss caused by ASPV infection. Biosensor is a promising user-friendly detection tool that could transduce biological or chemical interactions into electric signals. Among various types of biosensors, aptasensor, which use aptamers as recognition elements show potential as a high throughput, in-field test. The goal of this thesis is to develop an electrochemical aptasensor testing system for ASPV detection. The quality control study of laser inscribed graphene (LIG) based working electrode of the biosensor was conducted …

Investigating Effect Of Seed Source And Developing Germination Protocols To Improve Success In Restoration Of Arkansas Tallgrass Prairies, Rhiannon Spencerosa

Graduate Theses and Dissertations

American tallgrass prairie has faced losses estimated at 87-98% of original land area since European settlement. Native seeds are often used to supplement struggling or extinct plant populations in tallgrass prairie restoration and establishment sites. Two main considerations in restoration and establishment are from where to source seed and how to obtain high germination rates. In order to determine the effect of seed source, a common garden experiment was performed in Fayetteville, Arkansas in 2022 with five prairie species: Andropogon gerardii (big bluestem), Bouteloua curtipendula (sideoats grama), Panicum virgatum (switchgrass), Schizachyrium scoparium (little bluestem), and Sorghastrum nutans (Indiangrass). Seed was …

Estimating The Functional Consequences Of Intra-Specific Trichome Variation Of Tomato, Solanum Lycopersicum On The Specialist Herbivore, Manduca Sexta, Satinderpal Kaur

Theses and Dissertations

Chapter 1: Plants have a wide array of defenses against herbivores and hence they must confer trade-offs between growth and defense related traits. By using Solanum as a model genus, the major plant defense fitness trade-off hypotheses are reviewed in this chapter along with their assumptions and examples.

Chapter 2: This chapter provides an overview of the enormous intra-specific diversity in trichome morphology in tomato, Solanum lycopersicum. Also, the trichome sub-types are analyzed for the variations in density and dimensions in 10 varieties of tomato by using desktop scanning electron microscope.

Chapter 3: This chapter examines the functional consequences …

Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah

Electronic Theses and Dissertations

Plants secrete peptide ligands and use receptor signaling to respond to stress and control development. Understanding these phenomena is key to improving plant health and productivity for food, fiber, and energy applications. Phytosulfokine (PSK), a sulfated peptide hormone, regulates plant cell division, growth, and stress tolerance via specific phytosulfokine receptors (PSKRs). This study uses fiber-optic fluorescence microscopy to elucidate trafficking of PSK in live plants. The microscope features two-color optics and an objective lens connected to a 1-m coherent imaging fiber mounted on either a conventional upright microscope body or 5-axis positioning system (X–Y–Z plus pitch and yaw). PSK and …

Influence Of Cover Cropping And Nitrogen Fertilization On Soil Properties And Cotton Productivity, Christianah Oladoye

All Dissertations

Conservation practices with cover crops have proven to be effective in nutrient enrichment, increased yield, and environmental stability. Field studies were conducted from 2019 to 2022 to evaluate the short-term effect of No cover crop [NC], RYE, a mix of rye + vetch [R+V], and mix of five species (radish, rye, vetch, clover, and lupin) [5W] on short term soil physical, chemical properties, cotton growth, and lint yield. Cover crops were planted in November and terminated in May of each year. Soil dry and wet aggregate fractions (0-0.05 m) and soil compaction (0-0.4 m depth) were measured at termination. The …

Effect Of Nanobubble-Oxygenated Water For Irrigation Of Sand-Based Golf Course Putting Greens, Eric Deboer

Graduate Theses and Dissertations

Nanobubbles (NBs) are sub-micron, stable cavities of gas. The properties of NBs theoretically allow long bubble residence times and high gas dissolution rates resulting in the supersaturation of oxygen in water. Adequate soil aeration is a constant concern for producers of agricultural and horticultural crops. Because of their unique properties, NBs have been investigated for oxygenating water used in the irrigation of various agricultural and horticultural crops to increase soil oxygen concentration. Creeping bentgrass (Agrostis stolonifera L.) is the most widely used turfgrass for golf course putting green surfaces. Golf course superintendents use various methods to increase soil oxygen in …

Investigating The Impact Of Edaphobacter Aggregans (Wbg-1) On Arabidopsis Thaliana Development, Julia Talbert

Undergraduate Research Symposium

Acidobacteria is a phylum of bacteria that make up 50% of soil microbes. While making up a large proportion of bacteria found in soil, this phylum is largely unexplored with limited information about the bacteria and their impact on plant growth. The selected target of this study is Edaphobacter aggregans, WBG-1, which is a part of a subdivision of acidobacteria. Examining the bacteria’s effects on the development of the model plant Arabidopsis thaliana will provide insight into understanding this unknown phylum of soil-dwelling bacteria. Acidobacteria are an important realm to investigate as they affect agriculture practices. With Missouri being such …

Sensing Is A Far Cry From Sentience, Antonio Damasio, Hanna Damasio

Animal Sentience

The hypothesis that plants might be sentient confuses the notion of sentience (or consciousness) with that of sensing. Sentience/consciousness implies feeling, experience, and subjectivity. Sensing does not. Plants can sense/detect and even respond appropriately in the absence of any sentience/consciousness.

What If Plants Compute?, Jordi Vallverdú

Animal Sentience

The unexpended cognitive capacities of plants suggest the possibility of combining them with advances in computation. It is important to explore such a new field of research despite the incompleteness of the empirical support for it.

The Intersection Of Herbicide Policy, Exposure, And Health At The University Of Connecticut, Katherine Hayward

Honors Scholar Theses

Pesticides play an extremely complicated role in our everyday lives. From the water you use to make your coffee, to the breastmilk your neighbor provides for their child, to the lake your dog swims in, chemical pesticides or their byproducts have been found in nearly every corner of our lives. The chemicals used in synthetic herbicides, a subcategory of pesticides, have far reaching negative impacts on human health, biodiversity, and water quality. Despite there being numerous published studies on the relationships between pesticide exposures and health, there is still ongoing discord and controversy surrounding their role in our lives. After …

Plant Sentience: The Burden Of Proof, Jon Mallatt, David G. Robinson, Michael R. Blatt, Andreas Draguhn, Lincoln Taiz

Animal Sentience

Segundo-Ortin & Calvo’s (2023) target article takes a less speculative and more evidence-based approach to plant sentience than did previous works promoting that idea. However, it retains many of the idea’s longstanding difficulties such as starting from a false dichotomy (plants must be either hardwired or sentient), not accepting the full burden of proof for an extraordinary claim, confusingly redefining accepted cognitive terms, implying cell consciousness, not adopting the most parsimonious explanations for plant behaviors, and downplaying all the counterevidence. We advise rectifying these problems before plant sentience can become a full-fledged scientific domain.

Bryophytes Of Goochland County, Virginia, Mikayla Quinn

Honors Theses

Bryophytes are non-vascular land plants that include mosses, liverworts, and hornworts. Although easier to overlook because of their smaller size, bryophytes are a fundamental part of the ecosystem. As such, maintaining record of their biodiversity is important. Yet, records of bryophyte species in Goochland County, VA were low compared to more thoroughly documented counties such as Prince Edward County. This study expands the documentation of bryophyte flora and presents a checklist of bryophyte species found Virginia’s Goochland County from 2020-2023. Fieldwork conducted at public and privately-owned properties throughout the county between January 2020 and March 2023 yielded 702 specimens that …

Impact Of Drought And Fertilizer Use On The Photosynthesis Rate Of Cucumber And Sweet Corn Under Ambient And Elevated Atmospheric Co2 Conditions, Kate Fenske

Celebrating Scholarship and Creativity Day (2018-)

No abstract provided.

A Deep Learning Framework For Processing And Classification Of Hyperspectral Rice Seed Images Grown Under High Day And Night Temperatures, Víctor Díaz-Martínez, Jairo Orozco-Sandoval, Vidya Manian, Balpreet K. Dhatt, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

A framework combining two powerful tools of hyperspectral imaging and deep learning for the processing and classification of hyperspectral images (HSI) of rice seeds is presented. A seed-based approach that trains a three-dimensional convolutional neural network (3D-CNN) using the full seed spectral hypercube for classifying the seed images from high day and high night temperatures, both including a control group, is developed. A pixel-based seed classification approach is implemented using a deep neural network (DNN). The seed and pixel-based deep learning architectures are validated and tested using hyperspectral images from five different rice seed treatments with six different high temperature …

Antibacterial Activity Of Native Plants In Arkansas, Kayla L. Medina, Raven L. Turner, Katie Huffman

ATU Scholars Symposium

American beautyberry (Callicarpa Americana), Sugarberry (Celtis laevigata) and Red buckeye (Aesculus pavia) are native plants of Arkansas. Plant families with species having high chemical compounds can have antimicrobial properties. In this study, the antibacterial properties of the plants are investigated against three gram positive (Bacillus cereus, Bacillus subtilis, and Staphylococcus epidermidis) and three negative bacteria (Alcaligenes faecalis, Escherichia coli, and Serratia marcescens). The disc diffusion assay method is employed to identify any potential antibacterial properties of the plants. For this experiment, 6.41 g of dehydrated plant material (leaves for both species) was combined with 50 mL of 75% ethanol creating …

Entropy And Energy Profiles Of Chemical Reactions, Johannes C. B. Dietschreit, Dennis J. Diestler, Rafael Gómez-Bombarelli

Department of Agronomy and Horticulture: Faculty Publications

The description of chemical processes at the molecular level is often facilitated by use of reaction coordinates, or collective variables (CVs). The CV measures the progress of the reaction and allows the construction of profiles that track the evolution of a specific property as the reaction progresses. Whereas CVs are routinely used, especially alongside enhanced sampling techniques, links between profiles and thermodynamic state functions and reaction rate constants are not rigorously exploited. Here, we report a unified treatment of such reaction profiles. Tractable expressions are derived for the free-energy, internal-energy, and entropy profiles as functions of only the CV. We …

Plant Sentience: A Hypothesis Based On Shaky Premises, Carel Ten Cate

Animal Sentience

Plants may produce fascinating behavioural phenomena for which the label ‘cognitive process’ may be applicable, at least by some definitions. Segundo-Ortin & Calvo (2023) base their hypothesis that plants might be sentient on the premise of demonstrated presence of cognitive complexity. However, the way phenomena are ascribed, and how the term ‘cognitive’ is used by Segundo-Ortin & Calvo, deviates from the common practice in studies of animal cognition, implying greater complexity than seems justified. It thus provides a questionable basis for attributing sentience to plants.

Plant Sentience: "Feeling" Or Biological Automatism?, Andrea Mastinu

Animal Sentience

Sentience refers to the ability of an organism to have subjective experiences such as sensations, emotions and awareness. Whereas some animals, including humans, are widely recognized as sentient, the question of whether plants are sentient is still debated among scientists, philosophers, and ethicists. Over the past 20 years, many scientists such as Trewavas, Baluška, Mancuso, Gagliano, and Calvo have reported interesting discussions about memory, behavior, communication, and intelligence in plants. However, the reported conclusions have not convinced the entire scientific community. In this commentary, I would like to focus on two critical aspects related to sentience: cognition and emotion

Soil Microbial Community Composition Of White Oak Mountain, Tennessee, Matthew Gano, Timothy D. Trott

Research in Biology

Abstract - Soil microbial communities are responsible for nutrient cycling in terrestrial ecosystems and have symbiotic and parasitic relationships with the plant community. However, little is known about the factors that determine the soil microbial community composition. In this study we examined how spring wildflower diversity and geographical factors influence the soil microbial community composition of the second growth oak hickory forests of White Oak Mountain in Southeast Tennessee. The characterization of the soil microbial community was completed with 16S/18S/ITS rDNA amplicon sequencing of total DNA extracted from soil samples that were normalized for each sample plot. Here we characterize …

The Bellarmine Bee Bed: Organizing A Native Plant Garden Using Feedback From The Local Community, Kate Moran

Undergraduate Theses

Animal pollinators are the cornerstone of healthy ecosystems. Their survival is essential for the persistence of entire food chains: from the flowers they cross-pollinate directly, to the animals who depend on those plants for nutrition. The establishment of pollinator gardens—particularly ones that consist of native plants—is an effective way to enhance their biodiversity, abundance, and well-being.

The main goal of this thesis is to construct a pollinator garden that maximizes the benefits for animal pollinators using feedback from local gardeners. A survey was used to gather information about the popularity and preferences of 40 flowering plants, and after analyzing the …

Divergent Metabolic Changes In Rhizomes Of Lowland And Upland Switchgrass (Panicum Virgatum) From Early Season Through Dormancy Onset, Nathan A. Palmer, Gautam Sarath, Michael J. Bowman, Aaron J. Saathoff, Serge J. Edmé, Robert B. Mitchell, Christian M. Tobias, Soundararajan Madhavan, Erin D. Scully, Scott E. Sattler

Department of Agronomy and Horticulture: Faculty Publications

High-biomass-yielding southerly adapted switchgrasses (Panicum virgatum L.) frequently suffer from unpredictable winter hardiness at more northerly sites arising from damage to rhizomes that prevent effective spring regrowth. Previously, changes occurring over the growing season in rhizomes sampled from a cold-adapted tetraploid upland cultivar, Summer, demonstrated a role for abscisic acid (ABA), starch accumulation, and transcriptional reprogramming as drivers of dormancy onset and potential keys to rhizome health during winter dormancy. Here, rhizome metabolism of a high-yielding southerly adapted tetraploid switchgrass cultivar, Kanlow—which is a significant source of genetics for yield improvement—was studied over a growing season at a northern …

Differential Behaviour Of Guineagrass (Panicum Maximum Jacq.) Hybrids, With Different Al+3 Reactions, As To Major Nutrient Translocations To The Leaves, R. S. Paterniani, J. A. Usberti Jr., J. C. Werner

IGC Proceedings (1977-2023)

Most of the Brazilian cultivated pasture fields presents soils with high Al⁺³ levels and liming is economically unfeasible. So, there is an urgent need for grasses with good forage yielding potentials that can withstand Al⁺³ deleterious effects (abnormal root development: short, thick and poorly branched roots, which are unable to effectively translocate water and essential nutrients to the leaves) (Foy, 1984); as a consequence, susceptible genetic materials have their field persistences greatly affected, mainly during drought periods. Researches on Al⁺³ reaction are usually compare supposedly resistant/tolerant genotypes with a resistant control check; doing so, the genotypic effect …

Animal Performance And Productivity Of New Ecotypes Of Brachiaria Brizantha In Brazil, Valéria P. B. Euclides, Manuel C. M. Macedo, Cacilda B. Do Valle, R. Flores, M. P. Oliveira

IGC Proceedings (1977-2023)

Brazil has the competitive advantage of a very dynamic and cost effective animal production system on pastures over other countries. The pursuit for more productive forages that will result in higher quality beef at a lower cost is then justified. Brachiaria is the most important forage genus utilised in Brazil, thus an intense search for new cultivars amongst collected and introduced ecotypes from Africa is underway. Following agronomic evaluation of this material in plots, 8 pre-selected Brachiaria ecotypes were tested under intermittent grazing in paddocks (Euclides et al., 2001). Continuing on the process of cultivar development, two out of …