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Infection Rates And Distribution Of Trypanosoma Cruzi In Triatomine Insects From Several Public Parks Of Starr, Hidalgo And Cameron Counties, Carlos Guzman Jr.
Infection Rates And Distribution Of Trypanosoma Cruzi In Triatomine Insects From Several Public Parks Of Starr, Hidalgo And Cameron Counties, Carlos Guzman Jr.
Theses and Dissertations - UTB/UTPA
Chagas disease is caused by the protozoan Trypanosoma cruzi and is a major public health concern in many areas of the world, including the United States. The disease is transmitted by insect vectors known as kissing bugs from the subfamily Triatominae. While the majority of studies focus on domestic and peri-domestic collections, this study collected insect vectors from state parks in the Lower Rio Grande Valley. PCR analysis was done to obtain infection rates for collected insects, and a morphological examination was done to check insects for gender. In total 18 insects were captured with 12 of the captured insects …
Exploration Of Nickel Tolerance And Hyperaccumulation In Arabidopsis Thaliana Transformed With Streptanthus Polygaloides Metal Tolerance Protein 1 (Spmtp1) Cdna, Madeleine K. Sano
Exploration Of Nickel Tolerance And Hyperaccumulation In Arabidopsis Thaliana Transformed With Streptanthus Polygaloides Metal Tolerance Protein 1 (Spmtp1) Cdna, Madeleine K. Sano
Theses and Dissertations - UTB/UTPA
This study evaluated the role of hyperaccumulator S. polygaloides Metal Tolerance Protein 1 (SpMTP1) in conferring Ni tolerance and accumulation in the non-accumulator Arabidopsis thaliana. Analysis for Ni content in transgenic Arabidopsis transformed with SpMTP1, following a 12-day treatment of 100 µM Ni, showed a significant increase in Ni concentration in comparison to the wild-type Arabidopsis and empty vector transformed plants. Exposure of transgenic Arabidopsis to nickel also resulted in a coordinated increase of antioxidant enzyme (superoxide dismutase, glutathione reductase, and catalase) activities in the transgenic Arabidopsis, suggesting that increased activities of these oxidative stress response (OSR) proteins may be …
Characterization Of Oxidative Stress Response Proteins In Metal-Tolerant And Metal-Sensitive Brassicaceae Plant Species, Luis M. De Santiago
Characterization Of Oxidative Stress Response Proteins In Metal-Tolerant And Metal-Sensitive Brassicaceae Plant Species, Luis M. De Santiago
Theses and Dissertations - UTB/UTPA
In this study the expression of oxidative stress response (OSR) proteins in nonaccumulator and hyperaccumulator plant species of the Brassicaceae family were characterized. Oxidative stress was induced via nickel treatment and proteins were characterized through western blotting and image analysis. Statistical analysis indicated that the nonaccumulator species Arabidopsis thaliana significantly decreased catalase (CAT), glutathione reductase (GR), copper/zinc-dependent superoxide dismutase (Cu/ZnSOD), iron-dependent SOD (FeSOD), manganese-dependent SOD (MnSOD) and metal tolerance protein 1 (MPT1) expression in response to Ni-treatment. The hyperaccumulator species Thlaspi montanum variety montanum displayed either no significant change or a significant increase in OSR regulation following Ni-treatment with the …
Ecosystem Services Of Urban Trees And The Impacts Of Urbanization, Jorge E. Cantu
Ecosystem Services Of Urban Trees And The Impacts Of Urbanization, Jorge E. Cantu
Theses and Dissertations - UTB/UTPA
The University of Texas- Pan American has conducted a complete survey of campus trees in partial fulfillment of the requirements for membership in the International Society of Arboriculture Designation of Tree Campus USA. This tree inventory was accomplished with the help of students whom were trained by faculty and foresters. Other than the completion of the tree inventory, this thesis had two main goals; 1) valuate the ecosystem services provided by campus trees 2) create a unique service learning project that other institutions can model. According to our calculations, the trees on campus have sequestered 568,652 kg of CO2, avoided …
Loss Of Mitochondrial Dna Causes Decreased Cell Viability, Alan M. Herrera
Loss Of Mitochondrial Dna Causes Decreased Cell Viability, Alan M. Herrera
Theses and Dissertations - UTB/UTPA
Mitochondria are an organellar network involved in cellular bioenergetics and apoptosis, and dynamically balance their organization between fusion and fission events. Mitochondrial DNA (mtDNA) and nuclear DNA combine to encode polypeptides for the complexes of oxidative phosphorylation (OXPHOS) in the mitochondrial inner membrane, which generate a transmembrane potential (ΔΨm) to synthesize ATP. Loss of ΔΨm causes mitochondrial fission, which appears to be associated with the progression of apoptosis, a critical cell death mechanism that allows tissue homeostasis, developmental sculpturing, and the removal of unwanted cells. Using cultured human cell models of decreased ΔΨm (both genetic mtDNA-depleted ρ 0 and pharmacological …
Functional Analysis Of The Mms19 Gene In Carica Papaya, Jorge A. Trujillo
Functional Analysis Of The Mms19 Gene In Carica Papaya, Jorge A. Trujillo
Theses and Dissertations - UTB/UTPA
All organisms face DNA-damaging radiation in the form of UV light and must have mechanisms to repair or undo damage. Plants being stationary organisms must cope with damaging UV rays in a molecular fashion and so have developed many forms of resistance. MMS19 is implicated in DNA repair indirectly as a nuclear encoded gene that binds onto protein assembly complexes in the cytosol. A mutant within the SunUp variety of Carica papaya has a large deletion for MMS19 and presents a diminutive phenotype. Deficient DNA repair mechanisms will shunt cells out of the natural cell cycle and reduce cell proliferation …
Differential Gene Expression Between Two Developmental Stages Of The Gené'S Organ In The Cattle Fever Tick, Rhipicephalus (Boophilus) Microplus, Jason P. Tidwell
Differential Gene Expression Between Two Developmental Stages Of The Gené'S Organ In The Cattle Fever Tick, Rhipicephalus (Boophilus) Microplus, Jason P. Tidwell
Theses and Dissertations - UTB/UTPA
The southern cattle fever tick (SCFT), Rhipicephalus microplus, is considered the most economically important ectoparasite of livestock worldwide and ranks sixth among the most pesticide resistant arthropods globally. This single-host hard tick is a vector of the infectious agents causing bovine babesiosis and anaplasmosis. The estimated impact of these SCFT-borne diseases on the livestock industry in the world is $7 billion annually. This project focuses on the Gené’s organ and addresses the need to identify novel targets that can serve as the basis for sustainable SCFT control strategies. Wax secreted by the Gené’s organ protects tick eggs from desiccation, bacterial …
The Role Of Oxidative Stress In The Rotenone Model Lymnaea Stagnalis, Homero L. Cantu
The Role Of Oxidative Stress In The Rotenone Model Lymnaea Stagnalis, Homero L. Cantu
Theses and Dissertations - UTB/UTPA
Parkinson’s disease (PD) is the most common neurodegenerative movement disorder, characterized by progressive depletion of dopamine (DA). Rotenone, a common pesticide, can induce PD like symptoms in animal models. The goal of this thesis is to quantify the levels and effects of reactive oxygen species (ROS) in brain tissue of the common neurobiological gastropod model, Lymnaea stagnalis, after treatment with Rotenone. The results show that rotenone causes a behavioral deficit and increases ROS production, especially superoxide. Furthermore, glutathione was depleted and protein carbonyl formation increased. These results are consistent with findings in human PD and the high levels of ROS …
Preliminary Transcriptome Analysis And Homeobox Gene Isonlation For Tomocerus Minor (Entomobryomorpha: Tomoceridae), Alejandro Alaniz
Preliminary Transcriptome Analysis And Homeobox Gene Isonlation For Tomocerus Minor (Entomobryomorpha: Tomoceridae), Alejandro Alaniz
Theses and Dissertations - UTB/UTPA
Collembola, or “springtails,” are small, edaphic arthropods classified as Entognatha; a group traditionally included as part of Hexapoda and sister-group to the true insects. However, some genetic studies suggest that they may instead have derived from a separate crustacean lineage rather than from a proto-Insecta lineage. The unique abdominal structures that develop on the collembolan ventral abdomen appear to be appendicular in origin – atypical to the canonical, appendage-less insect abdomen ground plan. I developed culture and embryo fixation protocols for; and sequenced and analyzed a multi-stage embryo transcriptome for Tomocerus minor (Collembola: Entomobryomorpha). This analysis annotated 14,417 distinct genes, …
A Preventive Maintenance Framework In Dairy Production Operations, Maria F. Vargas
A Preventive Maintenance Framework In Dairy Production Operations, Maria F. Vargas
Theses and Dissertations - UTB/UTPA
Dairy operations suffer frequent stops. Product shrinkage is a consequence of downtime, which includes losses of packaging material, scraped finish product and capacity. This work proposes a troubleshooting methodology to identify causes of downtime, estimation of waste cost, and minimization of operation disruptions by applying a combination of a cost function to assess waste, and performance measurements. The drinkable yogurt process is evaluated to find the principal areas for wasted bottles and yogurt. In order to make a decision about which of those sources to address, a General Cost Function is used to estimate waste cost which include measurements that …
Expression And Functional Characterization Of Mtp Genes From Arabidopsis Thaliana In Saccharomyces Cerevisiae, Yessica E. Cerino
Expression And Functional Characterization Of Mtp Genes From Arabidopsis Thaliana In Saccharomyces Cerevisiae, Yessica E. Cerino
Theses and Dissertations - UTB/UTPA
In this study the functional characterization and overexpression of Metal Tolerance Protein (MTP) cDNA were evaluated using a transgenic yeast (Saccharomyces cerevisiae) model system as a preliminary means for the characterization of metal tolerance conferred by putative Group III MTP genes from Arabidopsis thaliana. Metal disc assays for nickel, zinc, cobalt and cadmium treatments were performed to measure the tolerance imparted to yeast by the MTP cDNAs. Statistical analysis from zinc and cadmium assays showed AtMTP1 imparted the highest zinc tolerance in yeast, while AtMTPB1 imparted the highest cadmium and cobalt tolerance. However, AtMTPA2 and AtMTPB produced a decrease in …
Management Of Silverleaf Whitefly, Bemisia Argentifolii Bellows And Perring (Hemiptera: Aleyrodidae), Using Non-Crop Companion Plants In Organically-Managed Cantaloupe Systems In South Texas, Ruth Renee Colyer
Theses and Dissertations - UTB/UTPA
Field trials in three separate phases of research were carried out from March, 2010, to August, 2012, to determine the effects of inter-cropping cantaloupe (Cucumis melo var. inodorus) with select non-crop companion plants in an effort to develop organic production strategies for melons in South Texas without the use of pesticides. A research program was designed and initiated to assess the effects of the companion plants and their ability to: 1) attract insect pollinators, and 2) repel or suppress pest species without affecting beneficial natural enemy complexes. The hypotheses were: 1) that organically-managed cantaloupe systems grown with non-crop companion plants …
Isolation And Characterization Of Polychlorinated Biphenyl (Pcb) Degrading Bacteria Isolated From A Pcb Contaminated Reservoir In Donna, Tx, Sergio Cepeda
Theses and Dissertations - UTB/UTPA
The Donna Irrigation System (DIS) located in Donna, Hidalgo County, TX, was confirmed to be contaminated with polychlorinated biphenyls (PCBs) in 1993 and remediation of the site will be attempted in the future. The need to isolate novel PCB degrading bacteria for bioremediation has been an active area of research in recent decades; thus, it was hypothesized that a variety of microorganisms able to degrade PCBs could be isolated from sediments taken from the DIS. Two genes of the PCB degradation pathway, bphA1 and bphC, were detected in 43 bacterial isolates grown from DIS sediments using molecular and culture-based methodology, …
Effects Of Climate Change On The Potential Distribution Of 12 Endemic Lizards Of The Genus Plestiodon Of Mexico, Mayra Oyervides
Effects Of Climate Change On The Potential Distribution Of 12 Endemic Lizards Of The Genus Plestiodon Of Mexico, Mayra Oyervides
Theses and Dissertations - UTB/UTPA
Anthropogenic global climate change is a large scale threat to biodiversity. Species distribution models (SDMs) were created to assess the possible effects of climate change on the distribution of 12 Plestiodon lizards of Mexico. Species presence data was obtained from online databases, literature, and field data. Occurrences were correlated with 19 climatic variables from www.worldclim.org to model species' current suitable habitat. These models were then projected to future (2050) conditions for which bioclimatic information was downloaded from the CCAFS website. Forecasts were made using 4 General Circulatory Models, 2 IPCC scenarios, and the software MaxEnt. Models were replicated 10 times …
Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez
Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez
Theses and Dissertations - UTB/UTPA
Soil fertility and plant nutrition is crucial for a better yield and consistent harvest in the Rio Grande Valley for local farmers growing citrus trees. A field of oranges and a field of grapefruits were monitored and nutrition deficiencies were noticed that played an important role during fruit set. Soil samples that were taken throughout the year were analyzed via a carbon dioxide extraction method that mimics the way plants naturally take up nutrients or extract nutrients from every soil type. Macronutrients such as the N, P, K, Na, Ca, Mg and some of the micronutrients (Zn, Fe, Mn, and …
Rates Of Evolution And Point Mutations Of Bacterial Plant Pathogens Compared To Bacterial Vertebrate Pathogens, Alejandro Cantu
Rates Of Evolution And Point Mutations Of Bacterial Plant Pathogens Compared To Bacterial Vertebrate Pathogens, Alejandro Cantu
Theses and Dissertations - UTB/UTPA
The relationship between a pathogen and its host is a constant interaction; as the host evolves defense mechanisms to protect itself from the pathogen, the pathogen will evolve in order to evade them. During this evolutionary process, the genomes of bacterial pathogens can change due to different selection pressures exerted by the immune system of their respective hosts. This study aimed to determine how differences in selection pressures affect the evolution of plant and vertebrate pathogens. The focus of this study was to analyze population level changes in conserved genes, as well as species level changes in the Type III …
Snow Monkeys In South Texas, A Thirty Year Study Of Behavioral Adaptation, Lou E. Griffin
Snow Monkeys In South Texas, A Thirty Year Study Of Behavioral Adaptation, Lou E. Griffin
Theses and Dissertations - UTB/UTPA
A thirty year study of a transplanted species of primate, Macaca fuscata, Japanese snow monkey, documents the environmental influences on an intact troop relocated from Arashiyama, Japan to south Texas. These influences include novel disease, toxins, and predation. The effects of the environment on the social structure, hierarchy, and population of the primates are presented. The study begins in 1972 and is completed in 2002.
Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez
Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez
Theses and Dissertations - UTB/UTPA
This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …
Effects Of Habitat Enrichment On The Stress Level Of The Sit-And-Wait Predator Sand Boa (Gongylophis Colubrinus), Jose Manuel Cantu Martinez
Effects Of Habitat Enrichment On The Stress Level Of The Sit-And-Wait Predator Sand Boa (Gongylophis Colubrinus), Jose Manuel Cantu Martinez
Theses and Dissertations - UTB/UTPA
Conditions in which the animals are housed vary according to animal use. Conditions unfamiliar or unsuited to organisms usually induce stress. Stress is mirrored by a hormone cascade resulting in glucocorticoids. Of the glucocorticoids corticosterone is regarded as the most important. The corticosterone levels of sand boas (Gongylophis colubrinus) were measured under enriched and barren soil and cage features. Enriched soil consisted of enough dirt to allow borrowing. Enriched cage featured consisted of a wooded ball. Barren soil consisted of newspaper as substrate. Barren cage features consisted of plane newspaper. Snakes were subject to treatment for two weeks. No significant …
Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles
Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles
Theses and Dissertations - UTB/UTPA
Epiphytic pathogenic bacteria on the thorns of native LRGV plants may provide a defense mechanism for the plants. To test this, plant thorns were collected from LRGV plant species and aerobic and anaerobic bacteria were isolated in thioglycollate medium. Tests were performed to characterize the bacterial cultures. The 16S rRNA gene was sequenced to allow for species identification. Sixty-nine bacterial cultures were isolated, including gram-positive and gram-negative cell types. All utilized a variety of carbon sources for nutrients and 23% of isolates displayed hemolysis. Bacterial identification included members of the genus Bacillus, Pseudomonas, Serratia, and others. Most were opportunistic pathogens. …
Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang
Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang
Theses and Dissertations - UTB/UTPA
The AHB program is a chronic disease prevention program which provides resources for community health centers along the U.S.-Mexico border. Healthy dietary habits and fruit/ vegetable intake play important roles in maintaining human health. Eight factors were used to evaluate the success of the AHB program. Another twenty factors were considered to predict dietary habits and fruit/vegetable intake status. Chi-square and multinomial logistic regression were used to study their correlation. Results from analysis showed that factors like birth country, employment, diabetes, baseline HbA1c, limited by problems, overall program quality, group, and program duration were correlated to the dietary habits, and …
Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza
Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza
Theses and Dissertations - UTB/UTPA
To evaluate metal tolerance conferred by the overexpression of Metal Tolerance Protein 1 (MTP1) in transgenic non-accumulator plants such as Arabidopsis thaliana, a model system was developed in Saccharomyces cerevisiae containing either SfMTP1 cDNA, from the metal tolerant plant Streptanthus farnsworthianus, or SpMTP1 cDNA, from the hyperaccumulator Streptanthus polygaloides. Nonquantitative RT-PCR showed constitutive expression of MTP1 in both plant species. Alignment of SfMTP1 and SpMTP1 protein sequences shows a gap in SpMTP1 in a variable histidine region known to affect metal transport. Disk assays revealed SfMTP1 cDNA imparted greater Ni tolerance to yeast than SpMTP1 cDNA; however, SpMTP1 showed higher …
Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia
Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia
Theses and Dissertations - UTB/UTPA
Kleberg bluestem (Dichanthium annulatum) is an invasive grass species native to Africa but now found in southern United States, Mexico, and other tropical and subtropical countries throughout the world. Using the modeling software MaxEnt, climatic variables from WorldClim, the Intergovernmental Panel on Climate Change (IPCC) scenario A1B, and two General Circulatory Models: the Canadian model (Canadian Centre for Climate Modelling and Analysis or CCCMA), and the Australian model (Commonwealth Scientific and Industrial Research Organisation or CSIRO), several models were developed to determine the possible implications of climatic change on the suitable habitat for D. annulatum, in the year 2050. Models …
Characterization Of A Serine/Threonine Phosphatase Encoded By Mg_207 Of Mycoplasma Genitalium, Mario A. Martinez
Characterization Of A Serine/Threonine Phosphatase Encoded By Mg_207 Of Mycoplasma Genitalium, Mario A. Martinez
Theses and Dissertations - UTB/UTPA
Mycoplasma genitalium is a bacterium with no cell wall and the second smallest free-living organism. It is an intracellular parasite that causes urethritis in men and women. Symptoms of infection in women can be missed and include vaginal malodor and discharge, painful urination and sexual intercourse. M. genitalium infection is a serious, though preventable and treatable, infection. Recently, due its notable characteristics, many studies have revealed an enormous amount of genetic and structural information on this bacterium. Furthermore, many of its genes have been characterized. The uncovering of roles of genes involved in signal transduction via phosphorylation and dephosphorylation mechanisms …
Responses To Predator Recognition Odors In Marmorkrebs, Loren Samantha Beard
Responses To Predator Recognition Odors In Marmorkrebs, Loren Samantha Beard
Theses and Dissertations - UTB/UTPA
Marmorkrebs is a parthenogenetic crayfish with no indigenous populations. They have been introduced in several countries and could become an invasive species. Individuals introduced in Germany had longer, sharper spines, suggesting an adaptation to predators via developmental plasticity. This was tested by exposing juveniles to the odor of a fish during development and comparing them to controls. Subsequent spine length or sharpness did not differ. Other crayfish detect predators via an alarm cue, hemolymph, and exhibit avoidant behavior in response. I hypothesized that Marmorkrebs would also treat hemolymph as an alarm cue. The behavior of adult crayfish exposed to food, …
Assessment Of Oxidative Stress Gene Expression In Brassicaceae Plant Species Using A Real-Time Pcr Method, Florestella Ruiz
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 …
Early Embryology Of The Insect Oligotoma Saundersii (Embiidina) Using Targeted Genes As Developmental Landmarks, Omar Doria
Theses and Dissertations - UTB/UTPA
Embiidina, or "webspinners", is a small, sexually dimorphic, polyneopterous insect order and is the only order to spin silk throughout their life cycle. Unique morphological features and the phylogenetic position of Embiidina make it an attractive subject for study of the evolution and development of the insect body plan and the origin of novel morphological features. Oligotoma saundersii is easily cultured and a viable laboratory organism. It has a fairly standard short-germ embryogenesis process requiring 453 hours at 28°C with progressive development beginning in the anterior region. Preliminary work on targeted developmental genes has yielded small portions of seven genes. …
The Study Of The Parasitic Fauna In Sciaenops Ocellatus, Lower Laguna Madre, Texas, Veronica Abrigo
The Study Of The Parasitic Fauna In Sciaenops Ocellatus, Lower Laguna Madre, Texas, Veronica Abrigo
Theses and Dissertations - UTB/UTPA
Parasitological investigations provide information on ecosystem health because parasite prevalence and abundance are influenced by biotic and abiotic environmental changes. This survey classified the parasitic fauna of red drum, Sciaenops ocellatus, in the Lower Laguna Madre, TX. Fish (n = 239) were collected from four study sites (May 2005 - June 2006). Parasite identification consisted of digenean and monogenean trematodes, cestodes, larval nematodes, copepods, and protozoans. Parasite prevalence and host length was positively correlated from South Bay (r=0.473), Port Isabel (r=0.533), Arroyo(r=0.314), and Port Mansfield (r=0.630). Significant differences (p<0.001) between zone and parasite prevalence from Arroyo site indicated a higher prevalence of protozoa and monogeneans and reduced prevalence of digeneans. Statistical analyses indicated the greatest difference between Port Isabel and Arroyo sites ( divided by 2= 48.195; p<0.001; df= 14), and the least difference between South Bay and Arroyo sites ( divided by 2= 20.847; p= 1.06; df= 14).
Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia
Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia
Theses and Dissertations - UTB/UTPA
Non-native grasses can modify the soils they invade. This study investigated microbial variation among native and non-native grasses in the Lower Rio Grande Valley. We hypothesized that rhizospheres of non-native grasses would support a higher density of microorganisms; therefore microbial communities of invasive plants would exploit more carbon sources than those of native plants. A second hypothesis stated that Streptomyces bacteria from the rhizosphere of non-native grasses would be better competitors. Samples of grasses, and soil from their respective rhizospheres were obtained in Arroyo City, TX. Results indicated a higher bacterial colony density, total activity and number of substrates utilized …
Investigating Heavy Metal Accumulation And Oxidative Stress Tolerance Of Non-Accumulators And Hyperaccumulators In The Brassicaceae Plant Family, Fritzie Joy Into
Investigating Heavy Metal Accumulation And Oxidative Stress Tolerance Of Non-Accumulators And Hyperaccumulators In The Brassicaceae Plant Family, Fritzie Joy Into
Theses and Dissertations - UTB/UTPA
Physiological and enzymatic analysis indicated that the non-accumulator A. thaliana showed an oxidative stress response in all assays except for protein carbonylation. Other non-accumulator plant species showed a significant difference in oxidative stress response in the TBARS assay; however, for some assays no stress response was evident. The hyperaccumulator plant species showed no significant difference in oxidative stress as indicated by the all of the assays with the exception of T. montanum var. montanum which showed an oxidative stress response in the SOD assay. Basal catalase enzyme activity was notably higher in the hyperaccumulators T. montanum var. montanum and T. …