Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Soybean (9)
- Arabidopsis thaliana (7)
- Photosynthesis (6)
- Phytophthora sojae (5)
- Arabidopsis (4)
-
- Cadmium (4)
- Climate change (4)
- MiR156 (4)
- Suberin (4)
- Abiotic stress (3)
- Abscisic acid (3)
- Alfalfa (3)
- Gene expression (3)
- Potato (3)
- Salt stress (3)
- TuMV (3)
- Acclimation (2)
- Antarctica (2)
- Arabidopsis thaliana. (2)
- Avirulence (2)
- Brachypodium (2)
- Brassinosteroids (2)
- Calmodulin (2)
- Colonization (2)
- Drought (2)
- Drought stress (2)
- Elevated CO2 (2)
- Epigenetics (2)
- Gene regulation (2)
- Gene silencing (2)
Articles 1 - 30 of 97
Full-Text Articles in Entire DC Network
The Role Of Mycorrhizal Associations In Modulating Poplar Growth, Phytohormone Responses, And Mortality Under Elevated Co2 And Temperature Conditions, Joshua Jr Frank-Webb
The Role Of Mycorrhizal Associations In Modulating Poplar Growth, Phytohormone Responses, And Mortality Under Elevated Co2 And Temperature Conditions, Joshua Jr Frank-Webb
Electronic Thesis and Dissertation Repository
Climate change poses significant challenges to forests worldwide, particularly the Canadian boreal forest. Populus spp. are ecologically and economically important tree species that have had declining growth and survival due to elevated temperatures and droughts associated with climate change. Symbiotic microbes, such as mycorrhizal fungi, may increase plant growth under climate change conditions by altering tree metabolic profiles and increasing tree access to water and nutrients. My thesis explores the relationship between mycorrhizal fungi and a Populus hybrid (Populus x canadensis) grown under a range of future climate scenarios: ambient CO2 (400 ppm) or elevated CO2 …
Identification And Characterization Of Isoflavone Reductase Family Members In Soybean, Negin Azizkhani
Identification And Characterization Of Isoflavone Reductase Family Members In Soybean, Negin Azizkhani
Electronic Thesis and Dissertation Repository
Soybean’s yield is threatened by Phytophthora sojae, a pathogen responsible for stem and root rot disease. Glyceollins, unique antimicrobial agents specific to soybeans in partially preventing P. sojae infection, are derived from the isoflavonoid branch of the general phenylpropanoid pathway. One pivotal enzyme exclusively involved in glyceollin synthesis in soybean is the isoflavone reductase (GmIFR), which catalyzes the 2'-hydroxydaidzein conversion to 2'-hydroxy-2,3-dihydrodaidzein as a precursor for glyceollin biosynthesis. To comprehensively identify all members of the GmIFR gene family within the soybean genome, keyword and blast protein searches were conducted, identifying 98 putative GmIFRs. Among these candidates, …
Freezing Tolerance Of Herbaceous Legumes Within Southwestern Ontario: Evidence Of Disproportionate Freezing Sensitivity, Samuel L. Rycroft
Freezing Tolerance Of Herbaceous Legumes Within Southwestern Ontario: Evidence Of Disproportionate Freezing Sensitivity, Samuel L. Rycroft
Electronic Thesis and Dissertation Repository
Legumes (Fabaceae) represent a diverse and ecologically significant plant taxon; most described legumes form mutualisms with diazotrophic rhizobia, potentially fixing substantial quantities of nitrogen within habitats where they are well-established. Stressors causing lethal or sub-lethal impacts in legumes or rhizobial symbionts may therefore impact the nitrogen dynamics of such habitats. In recent decades, variability of winter temperatures, precipitation, and soil freeze-thaw cycling has increased in temperate regions. Without adequate snow cover to insulate roots and shoot bases, herbaceous plants will likely be exposed to more frequent or severe freezing. In southwestern Ontario, a pattern of disproportionate freezing sensitivity relative to …
Investigating Soil Microbiome Changes During Panax Quinquefolius Cultivation In New Gardens, Pok Man Paul Wan
Investigating Soil Microbiome Changes During Panax Quinquefolius Cultivation In New Gardens, Pok Man Paul Wan
Electronic Thesis and Dissertation Repository
Ginseng (Panax quinquefolius) is susceptible to ginseng replant disease (GRD), resulting in root rot and decreased yield when ginseng is grown in soils previously used for ginseng crops. Although fungal and oomycete pathogens are implicated, GRD is a complex disease and the changes in the soil when initially cultivating ginseng that lead to GRD remain unclear. This thesis reported changes in the soil microbiome from three new gardens in Norfolk County, Ontario over three years starting from seeding with ginseng. Over this period of cultivation, metabarcoding of the V4 region of the 16S ribosomal RNA gene clearly showed …
Molecular Identification And Characterization Of Heat Shock Protein 70 Family Proteins Essential For Turnip Mosaic Virus Infection In Arabidopsis Thaliana, Ziwei Tang
Electronic Thesis and Dissertation Repository
Turnip mosaic virus (TuMV) belongs to the RNA virus family of Potyviridae and genus Potyvirus. TuMV incurs agricultural losses by causing diseases in vegetable, oilseed, forage, and biofuel crops globally. Viruses are obligate intracellular parasites depending on the host cellular machinery to proliferate. Thus, molecular identification and functional characterization of host factors essential in the viral infection process may open up a new avenue towards developing genetic virus resistance. Eukaryotic translation initiation factor 4E (eIF4E) or its isoform (eIF(iso)4E) is a critical host factor for many potyviruses including TuMV. Heat shock protein 70 family proteins (HSP70) have been identified in …
Nitrogen Transfer From Cover Crops To The Subsequent Grain Crop And The Influence Of Variability In Winter Conditions, Spencer Heuchan
Nitrogen Transfer From Cover Crops To The Subsequent Grain Crop And The Influence Of Variability In Winter Conditions, Spencer Heuchan
Electronic Thesis and Dissertation Repository
Cover crops, which are used to provide ground cover after the harvest of the grain crop, can potentially improve the sustainability of agroecosystems by reducing nutrient losses. However, few data are available to document the extent to which cover crops improve both the retention of soil nitrogen (N) and the transfer of this N to the grain crop. The efficiency of this N transfer may be further influenced by variation in winter soil temperature; for example, reduced snow cover can increase the frequency and intensity of soil freezing, which can affect the survival of cover crops and the timing of …
Herbicide Mediated Selection Of Sulfonamide Resistant E. Coli, Laura P. Muntz
Herbicide Mediated Selection Of Sulfonamide Resistant E. Coli, Laura P. Muntz
Electronic Thesis and Dissertation Repository
Asulam is an herbicide that is structurally analogous to sulfonamide antibiotics (sulfas), with the potential to contribute to the global antibiotic resistance crisis by cross-selecting for sulfa-resistant bacteria. To determine if asulam can select for antibiotic resistant bacteria, isothermal titration calorimetry (ITC) was used to assess the binding affinity of asulam with the target protein of sulfas, dihydropteroate synthase (DHPS). ITC confirmed asulam interacts with DHPS, and in vitro directed evolution experiments showed that prolonged asulam exposure can select for sulfa-insensitive DHPS in E. coli. Since mobile sul genes also encode for sulfa-insensitive DHPS, the potential effect of asulam on …
Cadmium Uptake In Plants As Influenced By Selenium Uptake And Sulphate Availability, Marnie J. Demand
Cadmium Uptake In Plants As Influenced By Selenium Uptake And Sulphate Availability, Marnie J. Demand
Electronic Thesis and Dissertation Repository
With cadmium uptake by plants posing a risk to plants and consumers alike, strategies to reduce metal uptake are desirable. One strategy may be to apply selenium (as selenate) to the growth medium. I hypothesized selenate would yield greater lignification, with a higher proportion of cadmium bound to root cell walls. Consequently, higher selenium in plants would result in greater tolerance to cadmium. Additionally, since selenate is taken up in place of sulphate, providing the plants with high sulphate would inhibit uptake and translocation of selenium, mitigating selenate’s benefits of reducing cadmium uptake and translocation. Experimental results did not support …
The Biosynthesis Of Non-Protein Sulfur Amino Acid In Developing Seeds Of Common Bean, Zixuan Lu
The Biosynthesis Of Non-Protein Sulfur Amino Acid In Developing Seeds Of Common Bean, Zixuan Lu
Electronic Thesis and Dissertation Repository
The protein quality of common bean (Phaseolus vulgaris) is associated with the level of dietary essential sulphur amino acids – methionine and cysteine. Extra sulphur that cannot be stored in the protein pool accumulates as the non-protein amino acid S-methylcysteine (S-methylCys) and its dipeptide γ-glutamyl-S-methylcysteine (γ-Glu-S-methylCys). Previous studies have indicated that S-methylhomoglutathione (S-methylhGSH) is present in the developing seed of common bean. It is hypothesized that S-methylhGSH is the key intermediate in the biosynthetic pathway of the γ-Glu-S-methylCys that leads to …
Manipulating The Root Mycobiome To Improve Plant Performance And Reduce Pathogen Pressure In Corn (Zea Mays), Noor F. Saeed Cheema
Manipulating The Root Mycobiome To Improve Plant Performance And Reduce Pathogen Pressure In Corn (Zea Mays), Noor F. Saeed Cheema
Electronic Thesis and Dissertation Repository
Crop yield often varies within a field of a single genetically uniform crop plant, with the causes presumed to be a mix of both biotic and abiotic factors. Manipulating crop root mycobiomes could potentially increase yield by reducing pathogen impacts and improving access to soil water and nutrients. This study aimed to identify different fungal inoculation treatments that could increase the growth of corn seedlings sown in low productivity soils to that in high productivity soils and shift the root mycobiome composition. Fungal inoculation treatments did not have significantly different root mycobiome composition than seedlings grown in low yield control …
Role Of Hxxxd-Motif Acyltransferases In Suberin Biosynthesis, Yudelkis Indira Queralta Castillo
Role Of Hxxxd-Motif Acyltransferases In Suberin Biosynthesis, Yudelkis Indira Queralta Castillo
Electronic Thesis and Dissertation Repository
Suberin is a complex polymer comprising an aliphatic polyester and an aromatic polymer, co-deposited with soluble waxes. The aliphatic polyester is composed of fatty acids, ω-hydroxy fatty acids, α,ω-dicarboxylic acids, fatty alcohols, glycerol, and ferulate. In potato, alkyl ferulates, are a major component of suberin-associated waxes. The lignin-like aromatic polymer is comprised of hydroxycinnamic acids and monolignols. Members of the HXXXD/BAHD acyltransferase family are required for the biosynthesis of the aliphatic suberin polyester and suberin-associated waxes, but their possible role in the biosynthesis of the phenolic domain of suberin remains unexplored. Here I studied the function of three BAHD candidate …
Long-Term Vs. Short-Term Plant Responses To Warming And Nitrogen Addition In A Temperate Old Field, Breanna Craig
Long-Term Vs. Short-Term Plant Responses To Warming And Nitrogen Addition In A Temperate Old Field, Breanna Craig
Electronic Thesis and Dissertation Repository
Climate warming and atmospheric nitrogen (N) deposition are expected to have strong effects on plant productivity in temperate ecosystems over the next century. However, short-term experiments may not adequately address their potential effects because of lags in changes in species composition. I added new plots to a pre-existing field experiment to compare the short-term (1-2 year; new plots) vs. long-term (14-15 year; old plots) effects of warming and N addition on plant productivity, relative species abundances, plant tissue N content, and litter decomposition. In 2020, N addition increased aboveground plant productivity most in old plots and only increased belowground biomass …
The Analysis Of Ginsenosides In Ginseng Garden Soil, Karina Marie Kaberi
The Analysis Of Ginsenosides In Ginseng Garden Soil, Karina Marie Kaberi
Electronic Thesis and Dissertation Repository
American ginseng (Panax quinquefolius L.) produces natural products called ginsenosides. The biggest challenge Ontario commercial ginseng farmers face is ginseng replant disease. To understand the function of ginseng root exudates, ginsenoside accumulation and persistence over time were investigated. Currently, no reliable ginsenoside specific extraction method, characterizing the changes in soil chemistry exists. Ginsenoside extraction protocol optimization was required to determine how ginsenoside composition changed over time. Overall, protocol optimization resulted in a 30% increase in yield of ginsenosides compared to previous extraction protocols. In the ginseng gardens, ginsenoside accumulation occurs slowly and did not reach significantly measurable amounts until the …
Reconstructing Carbon Dynamics Of Alpine And Temperate Zone Lakes Using Stable Isotopic Analysis, Rebecca M. Doyle
Reconstructing Carbon Dynamics Of Alpine And Temperate Zone Lakes Using Stable Isotopic Analysis, Rebecca M. Doyle
Electronic Thesis and Dissertation Repository
Lake sediments integrate signals from the catchment, atmosphere and water column, offering a unique window through which to view changes in the carbon cycle. Carbon dynamics in lakes are changing due to nitrogen loading and anthropogenic climate warming (ACW), threatening the water quality of lakes. This thesis identifies how the carbon dynamics of lakes have responded to anthropogenically-driven forcings by comparing pre- and post- AD 1850 records preserved in lake sediments. First, the carbon dynamics of Barry Lake (Ontario, Canada), a low-elevation temperate lake, are investigated. Effective moisture (the net of water inputs and evaporation) is reconstructed using the carbon …
Molecular Identification And Characterization Of Viral Pathogens Infecting Sweet Cherry, Aaron J. Simkovich
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 …
Floral Traits And Carbon Dynamics Of Cucumber In Response To Climate Change, Sarah Josina Mcdonald
Floral Traits And Carbon Dynamics Of Cucumber In Response To Climate Change, Sarah Josina Mcdonald
Electronic Thesis and Dissertation Repository
Pollination by animals is an important ecosystem service that contributes to the reproduction of many angiosperms. Climate change may alter this mutualism by affecting floral traits that are important to pollinators. Using Cucumis sativus, I tested the effects of experimentally elevated temperature and CO2 concentration on flowering onset, flower number, flower size, and floral rewards. Additionally, to better understand plant carbon balance and investment in reproduction, I measured biomass partitioning and leaf carbon fluxes of plants under their growth conditions. Carbon dynamics were similar across treatments, and plants grown under high [CO2] and temperature showed similar …
Characterization Of Squamosa Promoter Binding Protein Like (Spl), And Its Role In Drought Stress Tolerance In Medicago Sativa (Alfalfa)., Alexandria K. Hanly
Characterization Of Squamosa Promoter Binding Protein Like (Spl), And Its Role In Drought Stress Tolerance In Medicago Sativa (Alfalfa)., Alexandria K. Hanly
Electronic Thesis and Dissertation Repository
Traditional breeding involving Medicago sativa (alfalfa), has resulted in minimal yield increases. Moreover, extreme environmental conditions threaten to further limit production. Strategies that make use of molecular tools – such as small non-coding RNA, miR156 – represent an innovative means by which to influence tolerance to abiotic stress. miR156 functions, at least in part, through the SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL) family of transcription factors. In this study, the role of SPL9 in regulating alfalfa development and drought tolerance is evaluated. Examination of alfalfa plants with RNAi-mediated SPL9 (SPL9-RNAi) showed that plant height, stem thickness, and internode …
Investigating The Role Of Carbon Stress In The Mortality Of Tamarack Seedlings Under A Warming Environment, Bridget K. Murphy
Investigating The Role Of Carbon Stress In The Mortality Of Tamarack Seedlings Under A Warming Environment, Bridget K. Murphy
Electronic Thesis and Dissertation Repository
Climate warming is increasing the frequency of climate-induced tree mortality events. While drought combined with heat is considered the primary cause of this tree mortality, little is known about whether high temperatures alone can induce mortality, or whether rising CO2 will increase survival. I grew tamarack in two experiments combining warming (0-8 ˚C above ambient) and CO2 (400-750 ppm) to investigate whether high growth temperatures led to carbon limitations and mortality. Using glasshouses, +8 ˚C warming with ambient CO2 (8TAC) led to 40% mortality despite thermal acclimation of respiration. Dying 8TAC seedlings had lower needle carbon concentrations …
Soybean Root Exudates Increase The Physiological Diversity Of Bacteria In Cadmium-Treated Soil, Leily Kazemi Movahed
Soybean Root Exudates Increase The Physiological Diversity Of Bacteria In Cadmium-Treated Soil, Leily Kazemi Movahed
Electronic Thesis and Dissertation Repository
Three soybean cultivars with contrasting retention of cadmium (Cd) in the root were grown in Cd-spiked nutrient solution and used to determine that symplastic compartmentalization of Cd in roots is probably responsible for retention of Cd in roots. Roots of the low Cd-accumulator AC Hime treated with 30 mM Cd exuded up to 10-fold higher concentrations of citric, succinic, fumaric and malic acids into the hydroponic solution when compared to control; concentrations of the same organic acids from the high Cd-accumulator Westag 97 increased by up to 3-fold. The same cultivars were grown in Cd-spiked soil and the physiological profiles …
Microrna156: A Short Rna With A Major Role In Abiotic Stress Tolerance In Alfalfa, Biruk Ayenew Feyissa
Microrna156: A Short Rna With A Major Role In Abiotic Stress Tolerance In Alfalfa, Biruk Ayenew Feyissa
Electronic Thesis and Dissertation Repository
The highly conserved plant microRNA156, miR156, affects various aspects of plant development and stress response by silencing SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors. Our understanding of the role of miR156 and its mode of action in alfalfa’s (Medicago sativa L.) response to drought and flooding is still elusive, and thus this study was aimed at filling this gap in knowledge. Physiological parameters, metabolite and transcriptional analyses showed an interplay between miR156/SPL13 and WD40-1/DFR to mitigate drought stress. Low to moderate levels of miR156 overexpression suppressed SPL13 and increased WD40-1 to fine-tune the DIHYDROFLAVONOL-4-REDUCTASE (DFR) level for …
Effects Of Elevated Temperature And Elevated Co2 On Leaf Carbon Fluxes In Boreal Conifers: Lab And Field Studies, Mirindi Eric Dusenge
Effects Of Elevated Temperature And Elevated Co2 On Leaf Carbon Fluxes In Boreal Conifers: Lab And Field Studies, Mirindi Eric Dusenge
Electronic Thesis and Dissertation Repository
Rising CO2 may warm northern latitudes up to 10 °C by the end of the century. However, responses of plant physiological processes (such as photosynthesis and respiration) and growth to climate change remain uncertain. Seedlings and mature trees of tamarack (a deciduous species) and black spruce (an evergreen species), North America dominant conifers, were exposed to combined warming (up to +9 ˚C) and elevated CO2 (up to +300 ppm). In seedlings, stomatal conductance (gs) tended to increase with warming in tamarack seedlings, while gsdeclined with warming in spruce. In both species, CO2 had …
Genome-Wide Occupancy Of Polycomb Group Proteins And Chromatin Remodeler Splayed And Their Interplay In Arabidopsis, Jie Shu
Electronic Thesis and Dissertation Repository
The Polycomb group (PcG) proteins form two protein complexes, Polycomb repressive complex 1 (PRC1) and PRC2, which are key epigenetic regulators in eukaryotes. PRC2 represses gene expression by catalyzing trimethylation of histone H3 lysine 27 (H3K27me3). In Arabidopsis thaliana, CURLY LEAF (CLF) and SWINGER (SWN) are two major H3K27 methyltransferases, playing essential roles in plant growth and development. Despite their importance, genome-wide occupancy profiles of CLF and SWN have not yet been determined and compared. In this thesis, I generated transgenic lines expressing GFP-tagged CLF/SWN and determined the genome-wide distributions of CLF and SWN in Arabidopsis seedlings. I also …
Carbon And Nitrogen Dynamics In Plants Grown At Low Co2 Conditions Of The Past, Andre Galvao Duarte
Carbon And Nitrogen Dynamics In Plants Grown At Low Co2 Conditions Of The Past, Andre Galvao Duarte
Electronic Thesis and Dissertation Repository
For most of the recent evolutionary history of plants, atmospheric CO2 concentrations have been far below modern values. However, little is known about how plants grown in a low CO2 environment balance their carbon demand for growth while meeting their requirement for nitrogen acquisition, the establishment of mycorrhizal fungal associations, and the production of defense compounds. Here, I investigated how low CO2 affects Elymus canadensis and Picea mariana by comparing their growth at low and current CO2 concentrations. I found that reduced N availability exacerbated low CO2 effects on growth, and reduced stomatal index and …
Identifying Brachypodium Distachyon Proteins Interacting With Histone Deacetylase Bdhd1, Alberto Giovanni Torrez
Identifying Brachypodium Distachyon Proteins Interacting With Histone Deacetylase Bdhd1, Alberto Giovanni Torrez
Electronic Thesis and Dissertation Repository
Current evidence has revealed the involvement of epigenetic mechanisms, including histone deacetylases (HDACs), in plant stress responses. In Arabidopsis thaliana, HDA19, belonging to the RPD3/HDA1 class, interacts with transcription factors to form repressor complexes. HDAC research mainly exists for dicotyledons, whereas research on monocotyledons is limited. Brachypodium distachyon is used as a model plant to investigate questions unique to monocot crops. BdHD1 is the closest homologous gene to HDA19 in B. distachyon. This study investigated potential protein-protein interactions between BdHD1 and each of BdMYB22, BdWRKY24, and BdHOS15. Protein interactions were investigated using yeast two-hybrid (Y2H) and bimolecular fluorescence …
Partial Characterization Of Putative Cyp86a Genes From Soybean, Trish Tully
Partial Characterization Of Putative Cyp86a Genes From Soybean, Trish Tully
Electronic Thesis and Dissertation Repository
Soybean (Glycine max [L.] Merr.) is a globally cultivated crop that is important to the sustainability of many industries. However, like all plants, optimal cultivation of soybean is threatened by detrimental environmental factors. For example, high yield of soybean is threatened by soil-borne pathogens like Phytophthora sojae. Resistance against P. sojae was previously positively correlated with aliphatic suberin deposition in soybean. As such, a deeper understanding of the biosynthesis of suberin may assist in engineering a resistant form of soybean, based on enhanced suberin content. In soybean, the ω-OH fatty acid monomers are predominant and most strongly correlated …
Quantitative Proteome Analysis Of Alfalfa In Drought Stress Under The Influence Of Mir156, Alpa Puri
Quantitative Proteome Analysis Of Alfalfa In Drought Stress Under The Influence Of Mir156, Alpa Puri
Electronic Thesis and Dissertation Repository
Medicago sativa is one of the most produced perennial forage crops in Canada. Drought stress is a major form of abiotic stress affecting the productivity and annual yield of alfalfa. A small noncoding RNA, miR156 has a role in abiotic stress tolerance, while regulating downstream SPL genes. In this study, whole leaf proteome and amino acid concentrations of miR156OE (A8) genotype of alfalfa under drought stress were quantified. In results, 3,000 proteins groups were identified using MaxQuant when searched against Medicago truncatula protein sequence database. Gene ontology analysis showed enriched proteins were involved in biological and molecular processes such as …
Suberin Biosynthesis And Deposition In The Wound-Healing Potato (Solanum Tuberosum L.) Tuber Model, Kathlyn Natalie Woolfson
Suberin Biosynthesis And Deposition In The Wound-Healing Potato (Solanum Tuberosum L.) Tuber Model, Kathlyn Natalie Woolfson
Electronic Thesis and Dissertation Repository
Suberin is a heteropolymer comprising a cell wall-bound poly(phenolic) domain (SPPD) covalently linked to a poly(aliphatic) domain (SPAD) that is deposited between the cell wall and plasma membrane. Potato tuber skin contains suberin to protect against water loss and microbial infection. Wounding triggers suberin biosynthesis in usually non-suberized tuber parenchyma, providing a model system to study suberin production. Spatial and temporal coordination of SPPD and SPAD-related metabolism are required for suberization, as the former is produced soon after wounding, and the latter is synthesized later into wound-healing. Many steps involved in suberin biosynthesis remain uncharacterized, and the mechanism(s) that regulate …
Investigating The Role Of Brachypodium Distachyon Cellulose Synthase 8 In Gluconacetobacter Diazotrophicus Colonization, Xuan Yang
Electronic Thesis and Dissertation Repository
Nitrogen is an essential nutrient for plant growth. Significant amount of nitrogen fertilizer is applied to crop field to maintain high yield. Alternatives to chemical nitrogen fertilizer are needed to reduce the costs of crop production and offset environmental damage. Gluconacetobacter diazotrophicus is a nitrogen fixing bacterium that was originally isolated from sugarcane and has been proposed as a possible biofertilizer for monocot crop production. However, the colonization of G. diazotrophicus in most monocot crops is limited and deep understanding of the response of the host plants to G. diazotrophicus colonization is still lacking. In this study, research was conducted …
Characterization Of The Coat Protein Of Turnip Mosaic Virus And Its Arabidopsis Interactors In The Virus Infection Process, Zhaoji Dai
Electronic Thesis and Dissertation Repository
Viruses are infectious and obligate intracellular parasites. Turnip mosaic virus (TuMV) is a member of the genus Potyvirus which comprises many agriculturally important viral pathogens that threaten crop production. Potyviruses are fully dependent on the host cellular machinery to fulfil their infection cycle in plant hosts. It is well accepted that viral coat protein (CP) is a multifunctional protein that plays key roles in virus propagation and host-virus interactions. This dissertation project aimed to investigate the role of CP in TuMV cell-to-cell movement, to identify the host interactors of TuMV CP, and further to characterize their roles in TuMV infection. …
Phylogeny, Heat-Stress And Enzymatic Heat-Sensitivity In The Antarctic Psychrophile, Chlamydomonas Sp. Uwo 241, Marc Possmayer
Phylogeny, Heat-Stress And Enzymatic Heat-Sensitivity In The Antarctic Psychrophile, Chlamydomonas Sp. Uwo 241, Marc Possmayer
Electronic Thesis and Dissertation Repository
Psychrophilic species, micro-organisms which are unable to grow at temperatures of or above 20°C, are abundant in perennially cold ecosystems across the globe. Intensifying scientific investigation of these organisms from ecological to molecular scales has underscored the ability of life on Earth to adapt to environments which seem inhospitable due to high or low temperatures, high salinity, pressure and light, and ultra-low nutrient availability. Psychrophilic organisms that are also photosynthetic represent a much more limited group than psychrophiles generally, as their habitats must be well buffered against the warming influence of the infra-red energy accompanying sunlight. Photosynthetic psychrophiles face the …