Life Sciences Commons^™

Assessing Stress Tolerance Of Organelle Small Heat Shock Protein Mutants In Arabidopsis Thaliana, Parth Patel

Masters Theses

Molecular chaperones are proteins found in virtually every organism and are essential to cell survival. When plants are heat stressed, they upregulate and downregulate multiple genes, many of which are associated with the heat shock response. Small heat shock proteins (sHSPs) are one class of molecular chaperones that are upregulated during heat shock. They are proposed to act as the first line of defense by binding to heat sensitive proteins and preventing their irreversible aggregation. However, many details of sHSP function remain to be discovered and exactly what proteins they protect is unresolved. In addition to cytosolic sHSPs found in …

Microsite Requirements For Successful Regeneration In Lowland Northern White-Cedar (Thuja Occidentalis) Forests, Jeanette Allogio

Electronic Theses and Dissertations

Declines in stands of northern white-cedar (Thuja occidentalis L., hereafter cedar) have been observed as both shifts in species composition and reductions in cedar densities, particularly those stands in lowland sites (Curtis 1946, Boulfroy 2012). While several factors inhibiting cedar regeneration have been identified, a thorough understanding of the conditions that best promote regeneration is lacking. Our objectives for the first chapter were to characterize the site conditions associated with successful regeneration in lowland cedar stands and to describe how spatial patterns of various cedar size classes relate to site preference and to regeneration dynamics. These objectives were achieved …

Inaction On Lead Despite The Relevant Knowledge: Predictors, Covariates, And Outreach Implications, Alessandra Rossi, Bernabas Wolde, Pankaj Lal, Melissa Harclerode

Department of Biology Faculty Scholarship and Creative Works

Testing residential soil and paint for lead provides actionable information. By showing where and how much lead exists on the residence, it allows one to quantify risk and determine the best ways to reduce exposure along with the corresponding health and financial costs. For these reasons, several federal and state programs offer outreach to audiences on the benefits of testing residential soil and paint for lead. Not all individuals who know about lead’s adverse health effects, however, test their residence for lead, potentially limiting the actionable information that could have helped to reduce their exposure. Such individuals represent a challenge …

Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster

Electronic Theses and Dissertations

Regional vegetation patterns of Texas beach plant communities were analyzed using cluster analysis, ANOSIM, SIMPER, NMDS, and ISA for fives zones representing the foredune complex of twenty Gulf Coast beaches. ANOVA revealed that zones differ in terms of percent bare sand, percent vegetative cover, and species richness. Cluster Analysis, ANOSIM, and SIMPER results indicate that Texas beaches can be divided into northern and southern regions based on differences in species composition of plant communities. Indicator Species Analysis (ISA) indicates that northern beaches are characterized by the presence of Rayjacksonia phyllocephala, Ambrosia Strophostyles, Ambrosia psilostachya, and Panicum amarum …

Genome-Wide Association Mapping And Genomic Prediction Of Anther Extrusion In Cimmyt Hybrid Wheat Breeding Program Via Modeling Pedigree, Genomic Relationship, And Interaction With The Environment, Anil Adhikari, Bhoja Raj Basnet, Jose Crossa, Susanne Dreisigacker, Fatima Camarillo, Pradeep Kumar Bhati, Diego Jarquin, Yann Manes, Amir M.H. Ibrahim

Department of Agronomy and Horticulture: Faculty Publications

Anther extrusion (AE) is the most important male floral trait for hybrid wheat seed production. AE is a complex quantitative trait that is difficult to phenotype reliably in field experiments not only due to high genotype-by-environment effects but also due to the short expression window in the field condition. In this study, we conducted a genome-wide association scan (GWAS) and explored the possibility of applying genomic prediction (GP) for AE in the CIMMYT hybrid wheat breeding program. An elite set of male lines (n = 603) were phenotype for anther count (AC) and anther visual score (VS) across three field …

Development Of Mping-Based Activation Tags For Crop Insertional Mutagenesis, Alexander Johnson, Edward Mcassey, Stephanie Diaz, Jacob Reagin, Priscilla S. Redd, Daymond R. Parrilla, Hanh T. Nguyen, Adrian Stec, Lauren A.L. Mcdaniel, Thomas E. Clemente, Robert M. Stupar, Wayne A. Parrott, C Nathan Hancock

Department of Agronomy and Horticulture: Faculty Publications

Modern plant breeding increasingly relies on genomic information to guide crop improvement. Although some genes are characterized, additional tools are needed to effectively identify and characterize genes associated with crop traits. To address this need, the mPing element from rice was modified to serve as an activation tag to induce expression of nearby genes. Embedding promoter sequences in mPing resulted in a decrease in overall transposition rate; however, this effect was negated by using a hyperactive version of mPing called mmPing20. Transgenic soybean events carrying mPing-based activation tags and the appropriate transposase expression cassettes showed evidence of transposition. Expression analysis …

Phenotypic Responses Of Sagebrush To The Southwestern North America Megadrought: A Genotype-By-Environment (Gxe) Approach, Kara A. Navock

Boise State University Theses and Dissertations

The Southwestern North America megadrought is an extreme climate event. Artemisia tridentata (big sagebrush) is the dominant, keystone species of sagebrush-steppe ecosystems in arid and semi-arid habitats of western North America. I conducted a genotype-by-environment (GxE) experiment on two putative genotypes (drought-tolerant, G1 and drought-sensitive, G2) and two cytotypes, diploid (2x) and tetraploid (4x), to determine the phenotypic responses of big sagebrush seedlings to drought. For three chlorophyll fluorescence parameters, my results indicate a complex set of factors influence sagebrush responses to drought, including canalization, adaptive phenotypic plasticity, cryptic genetic diversity, and GxE interactions. Variation in leaf temperature profiles of …

Genomic Selection Of Forage Agronomic Traits In Winter Wheat, Frank Maulana, Ki-Seung Kim, Joshua D. Anderson, Mark E. Sorrells, Twain J. Butler, Shuyu Liu, P. Stephen Baenziger, Patrick Byrne, Xue-Feng Ma

Department of Agronomy and Horticulture: Faculty Publications

Genomic selection (GS) can improve genetic gain of complex traits in plant breeding. Phenotyping agronomic traits of winter wheat (Triticum aestivum L.) for dualpurpose use is expensive and time-consuming. In this study, we compared the prediction accuracies of four GS models (RR-BLUP, GBLUP, GAUSS, and BL) for forage yield (FY), plant height (PH) and heading date (HD) of the hard winter wheat diversity panel (n = 298) using random and stratified sampling methods. In addition, we determined the appropriate training population (TP) size and marker density for GS of the traits. Moderate to high prediction accuracies ranging from 0.66 …

Characterization Of Genetic Sources Associated With Restorability And Seed Dimension In Arkansas Restorer Rice Lines, Ozgur Azapoglu

Graduate Theses and Dissertations

Hybrid rice (Oryza sativa L.) breeding offers a significant opportunity to enhance rice production, and the cultivation of a male sterile line is the most important factor in the success of cross-breeding. One of the key elements of hybrid rice production is to develop a restorer line that is assigned as the male parent. The restorer lines provide viable pollen for fertilization of the male sterile plant due to the presence of a restorer gene (Rf) in their genomes. Any superior restorer line applied to hybrid rice production must contain genes/quantitative trait loci (QTL) associated with the desirable agronomic traits …

Root Phosphomonoesterase As A Vital Component Of Increasing Phosphorus Availability In Tropical Forests, Kristine Grace Manno Cabugao

Doctoral Dissertations

Tropical forests, relative to other terrestrial ecosystems, exchange the largest amount of carbon with the atmosphere and also constitute a significant carbon sink. However, nutrient limitation, particularly of phosphorus (P), could limit growth of tropical forests and their function with the global carbon cycle. Thus, understanding root mechanisms to acquire P is necessary to representing the P cycle and corresponding interactions with plant growth. A large portion of total soil P in tropical forests occurs in organic forms, only accessible through root and microbial production of phosphatase enzymes. These phosphatase enzymes mineralize organic P into orthophosphate, the form of P …

Fungicide Resistance: Surveillance, Risk Assessment And Evolution In Two Soil-Borne Pathogens, Nikita Gambhir

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Fungicide-resistant pathogens are an increasing threat to fungicide efficacy and plant health. The goal of this dissertation was to advance the foundational knowledge required to prevent and detect fungicide resistance development in the seedling disease pathogen, Rhizoctonia zeae and the white-mold pathogen, Sclerotinia sclerotiorum. Corn and soybean fields in 12 states (IA, IL, IN, KS, KY, MI, MN, MO, ND, NE, SD, and WI) were surveyed for R. zeae. In vitro fungicide sensitivity was determined for 91 isolates to fludioxonil, sedaxane, and/or prothioconazole. Rhizoctonia zeae was sensitive to all fungicides (EC₅₀ < 3 µg/ml) except azoxystrobin (EC₅₀ > 100 µg/ml). In planta application of …

Evaluating The Impact Of Grafting On Local Tomato Production In Nebraska, Raihanah Hassim

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Vegetable grafting has been known to improve plant production under both biotic and abiotic stresses. With an increase in interest among local growers towards grafting production, it is important to provide enough vegetable grafting information. Therefore, the objective of this study is to assess the impact of grafting, rootstock cultivar, and local conditions and management on the yield and quality of tomato across the diverse growing and environmental conditions, specifically in Nebraska. Three open-field and one limited growing condition study were conducted between 2018 and 2019 across Nebraska. In the open-field trial, two determinant fresh market tomatoes, ‘Nebraska Wedding’ and …

Influence Of Burning And Grazing Management Practices On Subirrigated Sandhill Meadow Hay Production, Tara M. Harms

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Subirrigated meadows are a valuable forage resource to Sandhills ranching operations being used for hay production, grazing, or a combination of both. Practices that sustain meadow productivity should be encouraged to ensure a consistent feed supply for cattle. The potential influence of prescribed burning or pre-freeze and post-freeze grazing on forage production and quality are not well understood on these meadows. In grasslands, including meadows, excess dead plant material can accumulate, causing a potential reduction in forage yield and quality. Results of our three-year field study suggest that burning meadows in the spring is a suitable management option to remove …

Critical Period Of Palmer Amaranth Removal And Effects Of Late Season Herbicide Applications On Palmer Amaranth Seed Production, Jose De Sanctis

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Palmer amaranth is the most troublesome weed in agronomic crops in United States. Therefore, an integrated weed management approach is necessary to successfully manage this weed. The use of residual pre-emergence (PRE) herbicide applied at planting can delays the is one of the critical time of Palmer amaranth removal (CTPAR) giving farmers more time to prepare the weed control tactics and to preventing an unacceptable yield loss in soybean due to Palmer amaranth competition. Field experiments were conducted in 2018 and 2019 in a grower’s field infested with GR Palmer amaranth near Carleton, Nebraska, to determine the CTPAR in soybean …

Evaluating The Untapped Potential Of U.S. Conservation Investments To Improve Soil And Environmental Health, Andrea Basche, Katherine Tully, Nora L. Alvarez-Berrios, Julian Reyes, Laura Lengnick, Tabitha Brown, Jennifer M. Moore, Rachel E. Schattman, Lana Koepke Johnson, Gabrielle Roesch-Mcnally

Department of Agronomy and Horticulture: Faculty Publications

There is increasing enthusiasm around the concept of soil health, and as a result, new public and private initiatives are being developed to increase soil health-related practices on working lands in the United States. In addition, billions of U.S. public dollars are dedicated annually toward soil conservation programs, and yet, it is not well quantified how investment in conservation programs improve soil health and, more broadly, environmental health. The Environmental Quality Incentives Program (EQIP) is one of the major U.S. public conservation programs administered on privately managed lands for which public data are available. In this research, we developed a …

Dct4—A New Member Of The Dicarboxylate Transporter Family In C4 Grasse, Sarit Weissmann, Pu Huang, Madeline A. Wiechert, Koki Furuyama, Thomas P. Brutnell, Mitsutaka Taniguchi, James C. Schnable, Todd C. Mockler

Center for Plant Science Innovation: Faculty and Staff Publications

Malate transport shuttles atmospheric carbon into the Calvin–Benson cycle during NADP-ME C4 photosynthesis. Previous characterizations of several plant dicarboxylate transporters (DCT) showed that they efficiently exchange malate across membranes. Here, we identify and characterize a previously unknown member of the DCT family, DCT4, in Sorghum bicolor. We show that SbDCT4 exchangesmalateacrossmembranesanditsexpressionpatternisconsistentwitharoleinmalatetransportduringC4 photosynthesis. SbDCT4 is not syntenic to the characterized photosynthetic gene ZmDCT2, and an ortholog is not detectable in the maize reference genome. We found that the expression patterns of DCT family genes in the leaves of Zea mays, and S. bicolor varied by cell type. Our results suggest that …

Reducing Mowing Requirements In Home Lawn And Golf Course Turfgrass, Mark A. Keck

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Turfgrass systems are routinely managed by frequent mowing to increase aesthetics and function. Mowing is resource intensive with a high labor and energy demand. Reducing the number of mowings events in a growing season will decrease the labor and energy but may reduce quality as well. Previous work has looked at reducing mowing by changing the frequency and by using a plant growth regulator (PGR). Limited information is available about how to reduce mowing while maintaining acceptable quality. We looked at two different management practices to reduce mowing and maintain quality. The first study evaluated seven different mowing frequencies at …

Can Modeling Save Florida’S Native Bromeliads From The Evil Weevil?, Erin N. Bodine, Zoe S. Brookover, Brian D. Christman, Sydney L. Davis, Alexis Kohnke

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Use Of An Active Canopy Sensor Mounted On An Unmanned Aerial Vehicle To Monitor The Growth And Nitrogen Status Of Winter Wheat, Jie Jiang, Zeyu Zhang, Qiang Cao, Yan Liang, Brian Krienke, Yongchao Tian, Yan Zhu, Weixing Cao, Xiaojun Liu

Department of Agronomy and Horticulture: Faculty Publications

Using remote sensing to rapidly acquire large-area crop growth information (e.g., shoot biomass, nitrogen status) is an urgent demand for modern crop production; unmanned aerial vehicle (UAV) acts as an effective monitoring platform. In order to improve the practicability and efficiency of UAV based monitoring technique, four field experiments involving different nitrogen (N) rates (0–360 kg N ha⁻¹ ) and seven winter wheat (Triticum aestivum L.) varieties were conducted at different eco-sites (Sihong, Rugao, and Xinghua) during 2015–2019. A multispectral active canopy sensor (RapidSCAN CS-45; Holland Scientific Inc., Lincoln, NE, USA) mounted on a multirotor UAV platform was used …

Perspectives On Low Temperature Tolerance And Vernalization Sensitivity In Barley: Prospects For Facultative Growth Habit, Maria Munoz-Amatriain, Javier Hernandez, Dustin Herb, P Stephen Baenziger, Anne Marie Bochard, Flavio Capettini, Ana Casas, Alfonso Cuesta-Marcos, Claus Einfeldt, Scott Fisk, Amelie Genty, Laura Helgerson, Markus Herz, Gongshe Hu, Ernesto Igartua, Ildiko Karsai, Toshiki Nakamura, Kazuhiro Sato, Kevin Smith, Eric Stockinger, William Thomas, Patrick Hayes

Department of Agronomy and Horticulture: Faculty Publications

One option to achieving greater resiliency for barley production in the face of climate change is to explore the potential of winter and facultative growth habits: for both types, low temperature tolerance (LTT) and vernalization sensitivity are key traits. Sensitivity to short-day photoperiod is a desirable attribute for facultative types. In order to broaden our understanding of the genetics of these phenotypes, we mapped quantitative trait loci (QTLs) and identified candidate genes using a genome-wide association studies (GWAS) panel composed of 882 barley accessions that was genotyped with the Illumina 9K single-nucleotide polymorphism (SNP) chip. Fifteen loci including 5 known …

Distribution Of Antibiotic-Resistant Enterobacteriaceae Pathogens In Potable Spring Water Of Eastern Indian Himalayas: Emphasis On Virulence Gene And Antibiotic Resistance Genes In Escherichia Coli, Ashish Kumar Singh, Saurav Das, Santosh Kumar, Varsha Rani Gajamer, Ishfaq Nabi Najar, Yanchen D. Lepcha, Hare Krishna Tiwari, Samer Singh

Department of Agronomy and Horticulture: Faculty Publications

Every year millions of people die due to fatal waterborne diseases around the world especially in developing countries like India. Sikkim, a northeastern state of India, greatly depends on natural water sources. About 80% of the population of Sikkim depends on natural spring water for domestic as well as agricultural use. Recent waterborne disease outbreaks in the state raises a concerning question on water quality. In this study, we analyzed water quality especially for the detection of Enterobacteriaceae members from four districts of the state. Isolation with selective culture media techniques and taxonomic characterization of Enterobacteriaceae bacteria with 16S rRNA …

Development Of A New Habitat Mimicking Tool For Assessing Larval Salamanders In Temperate Forest Streams, Margaret E. Maloney, Eric B. Borth, Chris Skalski, Ryan W. Mcewan

Biology Faculty Publications

Small streams are a high priority for conservation and an important target for biomonitoring. Stream salamanders are a useful indicator for biotic integrity of headwater streams; however, assessing stream salamanders is a challenging endeavor and existing methods can cause habitat disturbance or require expensive equipment. Our goal was to develop an artificial habitat that mimics the natural habitat that salamanders prefer, leading to rapid colonization and that also (1) represents a standardized area and (2) is easy to handle for rapid assessment. After developing a new artificial habitat (the Maloney Salamander Hotel), we tested the device in a variety of …

Dissecting The Regulatory Network Of Sphingolipid Biosynthesis In Plants, Ariadna Gonzalez-Solis

Department of Biochemistry: Dissertations, Theses, and Student Research

Sphingolipids are a diverse group of lipids recognized as important components of cellular membranes and regulators of processes during development and in response to environmental stresses. Serine palmitoyltransferase (SPT) catalyzes the first step in sphingolipid biosynthesis and is a primary regulatory point for homeostasis. ORM proteins have been identified as negative regulators of SPT activity, however the mechanistic details of the regulation are only beginning to be understood. In this work, we show that ORM1 and ORM2 are essential for life cycle completion in Arabidopsis thaliana. Furthermore, the study of a structural ORM1 variant provided information about a transmembrane …

Exploration Of Antiviral Effects Of Rna-Dependent Rna Polymerases 3, 4 And 5 In Arabidopsis., Eli R. Kallison, Aleksandra Beric, Blake Meyers

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Small RNAs play a number of vital roles in plants, including viral resistance. A particular class of small RNA that regulates plant defense from pathogens, among other functions, is known as small interfering RNAs (siRNAs). A key player in the biogenesis pathway of siRNAs are RNA-Dependent RNA Polymerases (RDRs). There are six RDR proteins in Arabidopsis thaliana, three of which have well documented roles (RDRs 1, 2 and 6), and three of which have no documented role. Here, we look at the functions of the unstudied RDRs, RDRs 3, 4 and 5, to see whether they affect antiviral resistance.

Reproductive Ecology And Phenology Of Thalassia Testudinum (Hydrocharitaceae) In Tampa Bay, Florida, Sheila Scolaro

USF Tampa Graduate Theses and Dissertations

Successful sexual reproduction and recolonization are critical in maintaining genetic diversity within seagrass meadows. Thalassia testudinum flower, fruit and seedling production were assessed visually at 10 sites within Tampa Bay, Florida approximately every 4 weeks from May to July 2017 to determine if there is spatial and temporal variation in sexual reproductive effort and if location within a meadow effects sexual reproductive effort. Results from this study reveal strong temporal variability throughout the reproductive season. The month of May was observed as peak Thalassia testudinum anthesis and June was peak fruiting in Tampa Bay during 2017. Flower and fruit density …

Inheritability Of Ciprofloxacin-Induced Mitochondrial Mutations From Parental To Offspring Generation Using Quantitative Polymerase Chain Reaction, Rose Mccoy

Honors Theses

In all eukaryotes, mitochondria are known as the powerhouse of the cell (Siekevitz, 1957). In plants, however, their mitochondrial genome is especially strange. Plant mitochondrial genomes are extremely large and contain both linear and circular subgenomic DNA fragments. Plant mitochondrial genomes undergo a significant amount of mutations in the form of rearrangements. However, it is not known how often these rearrangements are inherited by the next generation. It is thought that plant cells that are still dividing have higher rates of DNA repair, such as double-strand break repair, to ensure the quality of that plant lineage. As follows, it is …

Detailed Genetic Analysis For Identifying Qtls Associated With Drought Tolerance At Seed Germination And Seedling Stages In Barley, Yasser S. Moursi, Samar G. Thabet, Ahmed Amro, Mona F.A. Dawood, P Stephen Baenziger, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Drought induces several challenges for plant development, growth, and production. These challenges become more severe, in particular, in arid and semiarid countries like Egypt. In terms of production, barley ranks fourth after wheat, maize, and rice. Seed germination and seedling stages are critical stages for plant establishment and growth. In the current study, 60 diverse barley genotypes were tested for drought tolerance using two different treatments: control (0-PEG) and drought (20%-PEG). Twenty-two traits were estimated for seed germination and seedling parameters. All traits were reduced under drought stress, and a significant variation was found among genotypes under control and stress …

Molecular Identification And Characterization Of Viral Pathogens Infecting Sweet Cherry, Aaron J. Simkovich

Electronic Thesis and Dissertation Repository

Stone fruits are a valuable crop grown worldwide, however pathogens such as viruses threaten fruit production by reducing tree health and fruit yield. In an orchard within the Niagara region of Ontario, symptoms typical of viral infection such as chlorosis and leaf deformation were seen on sweet cherry (Prunus avium L.) trees. Next generation sequencing was performed on symptomatic and asymptomatic leaves and four viruses were identified. On the tree displaying the most severe symptoms, Prune dwarf virus (PDV), was the only virus detected. A survey conducted during this work showed 42% of cherry trees on a single …

Hu Aquaponics Monitoring And Control System : European Annual Edunet Conference 2020, Rachel L. Fogle, Glenn P. Williams, Josh R. Krug

Presidential Research Grants

The functional purpose of the HU Aquaponics Monitoring and Control System Project is to develop an environmental and plant monitoring and control system for the HU Aquaponics Lab, located in the Student Union. The project involves the design and implementation of technology that will regularly take measurements from the environment (e.g., air temperature, water temperature, pH, dissolved oxygen, etc). PLCnext Technology will systematically collect, store, and web-publish the measurement data for HU researchers and the public to use for scientific research.

Hot But Not Dry: Modest Changes In Water Relations For An Epiphytic Bromeliad In A Tropical Dry Deciduous Forest, Saúl Hernández-Robinson, Eric A. Graham, Olivia Hernández-González, Roberth Us-Santamaría, José Luis Simá, Fernando Arellano-Martín, José Luis Andrade

All Faculty Scholarship for the College of the Sciences

Premise of research. Epiphytic bromeliads endure intense seasonal environmental changes in the canopy of dry tropical deciduous forests. The analysis of the physiological responses of these epiphytes to environmental changes can be useful in assessing their plasticity, vulnerability, and adaptations to such extreme habitats.

Methodology. We measured microenvironmental variables and water relations for plants of the epiphytic bromeliad Tillandsia brachycaulos in three microhabitats within the canopy of a dry tropical forest. We measured individual plants for seasonal and spatial differences in light, leaf temperature, osmotic potential, cell wall elasticity, and relative capacitance as indications of their physiological responses …