Biology Commons^™

The Effects Of Caffeine On Activity Levels And Motor Behaviors In The Honeybee, Apis Mellifera, Johana Castro

Theses and Dissertations

Caffeine is produced by plants as a defense mechanism against herbivores and pathogens. However, caffeine was found in floral nectar, which contradicts nectar's role in attracting pollinators. Interestingly, low concentrations of caffeine were shown to increase alertness and locomotion in mammals and invertebrates, indicating it may enhance the productivity of pollinators. This investigation examined how caffeine affects activity levels and motor behaviors in the honey bee, Apis mellifera. To test overall activity, forager bees were collected and fed 1 M sucrose to satiation. The following day, bees received 10 µl of 1.0 M sucrose alone or with caffeine ranging from …

Understanding The Distribution And Abundance Of Asclepias Prostrata In South Texas, Elizabeth Ann Gonzalez

Theses and Dissertations

Asclepias prostrata, commonly referred to as prostrate milkweed, is a rare South Texas native plant species. In February of 2023, A. prostrata was listed as a federally endangered species by the U.S. Fish and Wildlife Service. Due to the limited available observations and literature for A. prostrata, this study was completed to bring new information that could be utilized for future restorative efforts. This study includes multiple field observations of the plant’s morphology, plant-insect interactions, extraction and transplanting of the species, and a seed viability study. Results indicate that although A. prostrata has many pressures that limit its …

How Enhancers Regulate Wavelike Gene Expression Patterns, Christine Mau, Heike Rudolf, Frederic Strobl, Benjamin Schmid, Timo Regensburger, Ralf Palmisano, Ernst Hk Stelzer, Leila Taher, Ezzat El-Sherif

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

A key problem in development is to understand how genes turn on or off at the right place and right time during embryogenesis. Such decisions are made by non-coding sequences called ‘enhancers.’ Much of our models of how enhancers work rely on the assumption that genes are activated de novo as stable domains across embryonic tissues. Such a view has been strengthened by the intensive landmark studies of the early patterning of the anterior-posterior (AP) axis of the Drosophila embryo, where indeed gene expression domains seem to arise more or less stably. However, careful analysis of gene expression patterns in …

Soil Moisture Dynamics In Cover Cropping Systems: From Local To Global Scales, Manish Gautam

Theses and Dissertations

Cover cropping systems, which have gained recognition for their ability to enhance soil health and promote sustainability are also associated with potential risks related with declining soil moisture and pose a dilemma for farmers considering the adoption of cover crops in water deficit semi-arid settings worldwide. To address this pressing issue, we conducted a participatory cover cropping trial in the Lower Rio Grande Valley (LRGV) region, encompassing four different farms and supplemented this experiment with a meta-analysis to answer our soil moisture and climate parameters and quantify the impact of cover crops on soil moisture levels. The findings revealed that …

Comparative Analysis Of Soil Properties, Microbial Community Composition, And Yield Responses To Cover Crops In Different Ecoregions Of South Texas, Daphne Zapsas

Theses and Dissertations

Comprehensive understanding of soil properties, their interdependencies, and the effects of management practices is crucial for designing sustainable agricultural strategies. By adopting site-specific and need-based practices that enhance soil health, farmers can optimize crop growth, increase yield, and contribute to long-term environmental sustainability. Cover crops have been recognized for enhancing soil fertility, promoting microbial activity, and increasing organic matter content. However, while their effectiveness is well documented in temperate regions with readily available water, their impact in water limited systems in subtropical regions remains mixed. The aim of this study is to assess soil conditions in four different farms across …

Biological Flora Of Coastal Freshwater And Brackish Marshes: Cladium Jamaicense Crantz, Richard Stalter, Robert I. Lonard

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

Cladium jamaicense Crantz, also known as sawgrass, has a broad distributional range from the Atlantic coast of Virginia to Florida, to southern Texas, the Caribbean, and along the Atlantic coast of Mexico to Central America, and to Brazil. Cladium jamaicense typically occurs in oligotrophic sloughs and fresh and brackish marshes where optimal salinity values range from 0 to 3.5 ppt. This species is a long-lived perennial with a highly developed rhizome system with rhizomes up to 20 cm long and 2.5 to 10 mm in diameter. Asexual reproduction is common. Its fibrous root system comprises short dauciform roots characterized by …

Oxymatrine Loaded Crosslinked Pva Nanofibrous Scaffold: Design And Characterization And Anticancer Properties, Salahuddin Ahmed, Megan Keniry, Narcedalia Anaya-Barbosa, Victoria Padilla, Md Noushad Javed, Robert Gilkerson, Acharan S. Narula, Eman Ibrahim, Karen Lozano

Mechanical Engineering Faculty Publications

This study focuses on the fabrication, characterization and anticancer properties of biocompatible and biodegradable composite nanofibers consisting of poly(vinyl alcohol) (PVA), oxymatrine (OM), and citric acid (CA) using a facile and high-yield centrifugal spinning process known as Forcespinning®. The effects of varying concentrations of OM and CA on fiber diameter and molecular crosslinking were investigated. The morphological and thermo-physical properties, as well as water absorption of the developed nanofiber-based mats were characterized using microscopical analysis, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In vitro anti cancer studies were conducted with HCT116 colorectal cancer …

Habitat Use And Winter Site Fidelity Of Lincoln’S Sparrow (Melospiza Lincolnii) In The Lower Rio Grande Valley Of Texas, Timothy Brush, Hugh E. Conway, Catherine C. Brush

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

No abstract provided.

Pathogenicity Of Multiple Providencia Species (Enterobacteriales: Morganellaceae) To The Mass-Reared Mexican Fruit Fly (Diptera: Tephritidae), Bacilio Salas, Hugh E. Conway, Don C. Vacek, Christopher Vitek, Erin Schuenzel

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

Mexican fruit fly (Anastrepha ludens (Loew)) (Diptera: Tephritidae) represents a major threat to fruit production in the Western Hemisphere. Sterile insect technique is used to suppress and eradicate wild populations. Success of this control method necessitates weekly production of hundreds of millions of flies, their sterilization by irradiation, and their aerial release. Diet needed to produce large fly numbers are conducive to the spread of bacteria. Pathogenic bacteria were isolated from 3 rearing facilities and from multiple sources: eggs, larvae, pupae and spent diet, and were found to include some isolates identified to the genus Providencia (Enterobacteriales: Morganellaceae). We …

Population Genetics Among Rhipicephalus Sanguineus Ticks In The Lower Rio Grande Valley, Bianca Liana Guerra

Theses and Dissertations

Rhipicephalus sanguineus is a common tick species in the lower Rio Grande Valley of both human and veterinary concern. Two lineages of R. sanguineus have been described across the United States known as the tropical and temperate lineage. Both lineages can be differentiated morphologically, genetically, biologically, and by vector competence. The species name for both lineages has not been well established therefore this thesis will utilize their widely used identification. Both lineages have been identified in Texas. While the distribution of these lineages has been well-defined in some regions across the world, recent studies have observed sympatric populations in certain …

Road Mitigation Structure And Road Effect Zone Impacts On Rodent Community Composition, Activity, And Predator-Prey Dynamics In South Texas, Adam F. Sanjar

Theses and Dissertations

The effects of road mortality mitigation structures on rodent activity and rodent community composition are not fully understood, both on the regional scale of south Texas and in the broader field of road ecology. This is primarily due to the low conservation priority of most rodent species and the difficulty of noninvasively surveying for rodents effectively. This thesis focused on characterizing how rodents were impacted by both roads and mitigation structures in south Texas, and if rodents are a significant factor to consider when studying the road ecology of rodent predators in south Texas, particularly ocelots, bobcats (Lynx rufus …

Identifying Direct Foxo Targets Through Chromatin Immunoprecipitation Assays With Sequencing, Alma Lopez

Theses and Dissertations

Glioblastoma Multiforme (GBM) and basal-like breast cancer (BBC) are aggressive cancers associated with poor prognoses. Basal-like breast cancer (BBC) and glioblastoma multiforme (GBM) are poor prognosis cancers that lack effective targeted therapies. A deregulation of FOXOs has been linked to cancer, as they regulate the expression of genes involved in multiple cellular processes. Canonically, the FOXO family of proteins is generally considered tumor suppressors, but evidence suggests that they may be involved in cancer metabolism as well as angiogenesis. Research in our lab has found that these factors play a role in glycolysis and the developmental WNT pathway. Here we …

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 …

Activation Of Opa1 Processing In Differentiated Myoblast Cells, Omar Agustin Carrillo

Theses and Dissertations

Mitochondria are eukaryotic cellular organelles that play a role in energy production, apoptosis, integrated stress response, and aging. Mitochondrial dynamics is the physical fusion (interconnection) and fission (fragmentation) of mitochondria within a cell and tightly regulates mitochondrial functions. Optic atrophy 1 (OPA1) is a dynamin-related GTPase located in the inner mitochondrial membrane, and is responsible for inner mitochondrial membrane fusion. OPA1 exists in five isoforms, the two fusion-active long OPA1 (L-OPA1) and the three fusion-inactive short OPA1 (S-OPA1) isoforms. When the transmembrane potential (∆ψm) is aggravated, the inner membrane metalloprotease OMA1 is activated, causing the complete cleavage of L-OPA1 to …

Microbial Associations With Metcalf's Tryonia, Tryonia Metcalfi (Gastropoda: Cochliopidae), An Imperiled Ciénega Endemic, Russell L. Minton, Kathryn E. Perez

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

The Chihuahuan Desert swamps are a hotspot for imperiled organisms including freshwater springsnails and bacteria. Many of these taxa are endemic to the desert and to the individual waterbodies where they occur. Efforts to conserve diversity in these threatened areas must account for the life history of the organisms, but also interactions between organisms including microbes. We documented the microbial assemblage associated with Tryonia metcalfi, a critically imperiled freshwater snail endemic to a ciénega system in western Texas. We identified 14 bacterial families in our snail samples and determined a core assemblage of 19 bacterial taxa (4 of which …

Detection Of A Diverse Endophyte Assemblage Within Fungal Communities Associated With The Arundo Leaf Miner, Lasioptera Donacis (Diptera: Cecidomyiidae), Marie-Claude Bon, John A. Goolsby, Guy Mercadier, Fatiha Guermache, Javid Kashef, Massimo Cristofaro, Ann T. Vacek, Alan Kirk

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

The larvae of Lasioptera donacis Coutin feed on fungal communities lining galleries within the mesophyll of leaf sheaths of Arundo donax in an aggregative manner. It has been stated that L. donacis could have established a fundamental symbiotic relationship with one fungus, although the fungal composition of these communities remains unsettled. Using a culture-dependent approach and ITS sequencing, the present work characterizes and compares the fungal communities associated with L. donacis in Eurasia with the endophytes of A. donax in Texas where L. donacis is absent. The 65 cultivable isolates obtained from L. donacis fungal communities were sorted into 15 …

The Photochemical Evolution Of Polycyclic Aromatic Hydrocarbons And Nontronite Clay On Early Earth And Mars, Nina Kopacz, Maria Angela Corazzi, Giovanni Poggiali, Ayla Von Essen, Vincent Kofman, Teresa Fornaro, Hugo Van Ingen, Eloi Camprubi, Helen E. King, John Brucato, Inge Loes Ten Kate

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

The photochemical evolution of polycyclic aromatic hydrocarbons (PAHs), an abundant form of meteoritic organic carbon, is of great interest to early Earth and Mars origin-of-life studies and current organic molecule detection efforts on Mars. Fe-rich clay environments were abundant on early Earth and Mars, and may have played a role in prebiotic chemistry, catalyzing the breakdown of PAHs and freeing up carbon for subsequent chemical complexification. Current Mars is abundant in clay-rich environments, which are most promising for harboring organic molecules and have comprised the main studied features by the Curiosity rover in search of them. In this work …

Morphological Characterization Of Intraspecific Variation For Trichome Traits In Tomato (Solanum Lycopersicum), Satinderpal Kaur, Neetu Khanal, Robert K. Dearth, Rupesh R. Kariyat

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

Trichomes, the hairlike protuberances in plants, have been well known to act as the first line of defense against herbivores, and abiotic stresses, along with other structural defenses such as spines, thorns, and waxes. We previously reported the tremendous variation in trichome traits among different wild and cultivated Solanum species and demonstrated that trichomes types and density are traditionally miscalculated and often misnamed. However, intraspecific variation in trichome traits is poorly understood, although this has implications for stress tolerance and resistance breeding programs in economically important crop species and can also mediate ecological interactions at multiple trophic levels in their …

Predicting The Impact Of Climate Change On The Distribution Of Rhipicephalus Sanguineus In The Americas, Marcos Sánchez Pérez, Teresa Patricia Feria-Arroyo, Crystian Sadiel Venegas Barrera, Carolina Sosa-Gutiérrez, Javier Torres, Katherine A. Brown, Guadalupe Gordillo Pérez

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

Climate change may influence the incidence of infectious diseases including those transmitted by ticks. Rhipicephalus sanguineus complex has a worldwide distribution and transmits Rickettsial infections that could cause high mortality rates if untreated. We assessed the potential effects of climate change on the distribution of R. sanguineus in the Americas in 2050 and 2070 using the general circulation model CanESM5 and two shared socioeconomic pathways (SSPs), SSP2-4.5 (moderate emissions) and SSP2-8.5 (high emissions). A total of 355 occurrence points of R. sanguineus and eight uncorrelated bioclimatic variables were entered into a maximum entropy algorithm (MaxEnt) to produce 50 replicates per …

Greenbug Feeding-Induced Resistance To Sugarcane Aphids In Sorghum, Heena Puri, Edith Ikuze, Jessica Ayala, Isabella Rodriguez, Rupesh R. Kariyat, Joe Louis, Sajjan Grover

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

Plants are attacked by multiple insect pest species and insect herbivory can alter plant defense mechanisms. The plant defense responses to a specific herbivore may also contribute to the herbivore growth/survival on plants. Feeding by one insect species can modulate the plant defenses, which can either facilitate or hamper the colonization of subsequent incoming insects. However, little is known about the effect of sequential herbivory on sorghum plants. In this study, we demonstrate that a specialist aphid, sugarcane aphid (SCA; Melanaphis sacchari) grows faster on sorghum than a generalist aphid species, greenbug (GB; Schizaphis graminum). We also determined …

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, …

Evidence Of An Established Population Of Cherax Quadricarinatus (Von Martens, 1868) In South Texas, Usa, Adam Sanjar, Drew R. Davis, Richard J. Kline

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

Cherax quadricarinatus (von Martens, 1868) is a large parastacid crayfish (Decapoda: Parastacidae) native to Australia and Papua New Guinea. Due to various factors, C. quadricarinatus is an emerging invasive species in an increasing number of regions across the world. Deleterious ecological effects of C. quadricarinatus introduction have been documented in many of these regions, and its spread has been monitored and restricted where possible. Previously, only a small, isolated population of C. quadricarinatus in southern California had been reported within the continental United States. Here, we report the collection of three adult C. quadricarinatus from Brownsville, Cameron County, Texas, the …

The Known And Unknowns Of Aphid Biotypes, And Their Role In Mediating Host Plant Defenses, Neetu Khanal, Christopher Vitek, Rupesh R. Kariyat

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

Insect species are subjected to disparate selection pressure due to various biotic and abiotic stresses. Management practices including the heavy use of chemical insecticides and introduction of insect-resistant plant cultivars have been found to accelerate these processes. Clearly, natural selection coupled with human intervention have led to insect adaptations that alter phenotypes and genetic structure over time, producing distinct individuals with specialized traits, within the populations, commonly defined as biotypes. Biotypes are commonly found to have better fitness in the new environment and, in the case of aphids, the most commonly studied system for biotypes, have the ability to successfully …

Diel Activity Patterns Of Vector Mosquito Species In The Urban Environment: Implications For Vector Control Strategies, André Barretto B. Wilke, Adequate Mhlanga, Allisandra G. Kummer, Chalmers Vasquez, Maday Moreno, William D. Petrie, Art Rodriguez, Christopher Vitek, Gabriel L. Hamer, John-Paul Mutebi, Marco Ajelli

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

Mathematical models have been widely used to study the population dynamics of mosquitoes as well as to test and validate the effectiveness of arbovirus outbreak responses and mosquito control strategies. The objective of this study is to assess the diel activity of mosquitoes in Miami-Dade, Florida, and Brownsville, Texas, the most affected areas during the Zika outbreak in 2016–2017, and to evaluate the effectiveness of simulated adulticide treatments on local mosquito populations. To assess variations in the diel activity patterns, mosquitoes were collected hourly for 96 hours once a month from May through November 2019 in Miami-Dade County, Florida, and …

Revisiting Plant Defense-Fitness Trade-Off Hypotheses Using Solanum As A Model Genus, Sakshi Watts, Satinderpal Kaur, Rupesh R. Kariyat

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

Plants possess physical and chemical defenses which have been found to deter herbivores that feed and oviposit on them. Despite having wide variety of defenses which can be constitutive or induced, plants are attacked and damaged by insects associated with different mouthparts and feeding habits. Since these defenses are costly, trade-offs for growth and defense traits play an important role in warding off the herbivores, with consequences for plant and herbivore growth, development and fitness. Solanum is a diverse and rich genus comprising of over 1,500 species with economic and ecological importance. Although a large number of studies on Solanum …

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 …

The Foxo1 Inhibitor As1842856 Triggers Apoptosis In Glioblastoma Multiforme And Basal-Like Breast Cancer Cells, David Flores, Alma Lopez, Shreya Udawant, Bonnie Gunn, Megan Keniry

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

Basal-like breast cancer (BBC) and glioblastoma multiforme (GBM) are poor-prognosis cancers that lack effective targeted therapies and harbor embryonic stem gene expression signatures. Recently, our group and others found that forkhead box transcription factor FOXO1 promotes stem gene expression in BBC and GBM cell lines. Given the critical role of cancer stem cells in promoting cancer progression, we examined the impact of FOXO1 inhibition with AS1842856 (a cell-permeable small molecule that directly binds to unphosphorylated FOXO1 protein to block transcriptional regulation) on BBC and GBM cell viability. We treated a set of BBC and GBM cancer cell lines with increasing …

The Justice Challenge: Honors Endeavors Innovative Pedagogies Through The Grand Challenge Scholars Program, Jonathan Kotinek, Rebecca C. Bott-Knutson, Leigh E. Fine, Joy L. Hart, William Ziegler, Paul Knox, Timothy Nichols, Susan Sumner, Heidi Appel, Mark C. Andersen

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

Honors practitioners from fourteen colleges and programs across the country at land-grant, public, and minority-serving institutions partner with agricultural experts to secure a United States Department of Agriculture (USDA) Higher Education Challenge grant focused on the themes of food justice, climate justice, and sustainable agriculture. Authors describe the program’s origin, objectives, and curricular outgrowths, highlighting its efficacy for empowering students in areas of systems thinking, career readiness, leadership in the service of addressing social needs, and learning through civic engagement.

Nilgai, Boselaphus Tragocamelus And White-Tailed Deer, Odocoileus Virginianus Use Of Water Troughs With And Without Remotely Operated Field Sprayers For Potential Treatment Of Cattle Fever Ticks, John A. Goolsby, Mauricio Cruz, Reyes Garcia Iii, Lauren P. Maestas, Teresa Patricia Feria-Arroyo

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

Nilgai antelope, Boselaphus tragocamelus and white-tailed deer (WTD), Odocoileus virginianus are hosts of cattle fever ticks, Rhipicephalus (=Boophilus) microplus, in the Lower Rio Grande Valley of South Texas. Daily use of water troughs and ponds were observed to determine if these locations could be used for field treatment methods for cattle fever ticks using remotely operated field sprayers. Game cameras (n=16) were deployed between June 2020 and September 2022 at two private ranches in Cameron County, TX. Both nilgai and WTD visited water troughs equipped with motion detecting sprayers in similar numbers to ponds, but numbers of animal visits were …

Bobcat Identification, Abundance, And Behavior At Road Mitigation Structures In South Texas, Victoria Hanley

Theses and Dissertations

Highways in South Texas fragment the landscape and result in high road mortality rates for the endangered US ocelot (Leopardus pardalis). In response, the Texas Department of Transportation constructed nine wildlife crossing structures (WCS) on Farm-to-Market (FM) 106 which adjoins Laguna Atascosa National Wildlife Refuge in Cameron County, Texas. With ocelots being rare and elusive, bobcats (Lynx rufus) are often used as a surrogate species to study felid behavior at road mitigation structures in South Texas. Bobcats have unique markings which allow them to be individually identified. Three methods of individual identification of bobcats using camera …