Plant Biology Commons^™

Non-Target-Site Based Tolerance To Herbicides In Amaranthus Palmeri, Reiofeli Algodon Salas-Perez

Graduate Theses and Dissertations

Palmer amaranth, one of the most aggressive and damaging broadleaf weeds in the USA, has evolved resistance to multiple herbicide modes of action. The overall objective of this research was to elucidate the mechanisms by which Palmer amaranth adapt to herbicide selection stress. This research aimed (1) to evaluate the efficacy of fomesafen, glufosinate, glyphosate and trifloxysulfuron to Amaranthus populations; (2) identify candidate genes for endowing tolerance to glufosinate; (3) investigate the involvement of non-target-site resistance (NTSR) mechanism in an ALS-resistant population; and (4) to examine the molecular basis of resistance to PPO inhibitors in Palmer amaranth populations from Arkansas. …

The Role Of Ferric Reduction Oxidases In Plant Anti-Herbivore Defense., Virginia C. Nunamaker

College of Arts & Sciences Senior Theses

Iron is an essential element required for plants to carry out metabolic functions such as photosynthesis, heme biosynthesis, and chlorophyll biosynthesis. Within Arabidopsis thaliana, eight ferric reduction oxidase (FRO) genes function in iron uptake and homeostasis with tissue specific expression. However, little else is known regarding the biological role of FROs. Recent studies identify the FRO gene family as particularly responsive to the green leaf plant derived volatile (GLV) cis-3-hexenyl acetate (z3HAC). Since z3HAC acts as a wound signal and cues unaffected parts of the plant to prime defenses prior to herbivory, an increase in FRO activity in response …

Combining Translational And Functional Genomic Approaches To Augment Management Strategies Of Plant Parasitic Nematodes, Sandeep Sharma Khatiwada

Graduate Theses and Dissertations

Plant-parasitic nematodes pose a major threat to crop yield worldwide. Discontinued use of harmful chemicals has prompted the search for alternative management strategies that are effective yet environmentally friendly. Harpin proteins, which are derived from bacteria, and nematophagous fungi, natural predators of nematodes, are ideal for biological control of plant-parasitic nematodes. However, research on the efficacy of harpin proteins on nematodes, and biology of nematophagous fungi is minimal. Previously, a taxonomically uncharacterized nematophagous fungus designated ARF18 effectively suppressed nematode populations in soil. The overarching goal of this dissertation is to utilize applied and functional genomic approaches to augment management of …

Binding Of Maize Necrotic Streak Virus (Mnesv) 3’ I-Shaped Structure (3’ Iss) To Eukaryotic Translation Factors (Eifs) And Implication In Eif4f Mediated Translation Initiation, Qiao Liu

Dissertations, Theses, and Capstone Projects

5' m⁷GpppN cap and the 3' poly adenosine (A) tail of eukaryotic mRNAs are key elements for recruiting translation initiation machinery in canonical translation initiation. Unlike host mRNAs, many viruses lack these elements and yet they are translated efficiently. Plant viruses, in particular, have complex structures within their untranslated regions (UTR) that allow them to bypass some cellular translation control steps. In Maize necrotic streak virus (MNeSV) 3' UTR, an I-Shaped RNA Structure (ISS) has been reported to mediate the virus translation initiation progress. 3’ ISS binding with eIF4F has been shown to facilitate translation. 5’ -3’ kissing …

Interplay Of Dgat1, Pdat1 And Dgat2 Enzymes In Plant Triacylglycerol Assembly, Anushobha Regmi

Master's Theses

Acyl-CoA:diacylglycerol acyltransferase (DGAT) catalyzes the transesterification of fatty acid from acyl-CoA to diacylglycerol (DAG) forming triacylglycerol (TAG, a.k.a oils and fats). Most plants have at least two unrelated DGAT genes, DGAT1 and DGAT2. Plants predominantly express only one during oil synthesis; the reason, however is not clear. A few studies have indicated that each enzyme prefers DAG and acyl-CoA substrates with different fatty acid compositions. Industrially desirable seed oil composition can be obtained through genetic engineering by replacing the endogenous enzyme with one that has different substrate selectivity. In Arabidopsis thaliana, DGAT1 and another unrelated enzyme PDAT1 are essential …

Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price

Master's Theses

This study examines the effects of historical management by use of prescribed fire on Ilex glabra stems/m² and factors affecting the regrowth of I. glabra after a prescribed burn to gain beneficial knowledge for management purposes. Environmental factors and morphological parameters of I. glabra were sampled before and after a prescribed burn of the Longleaf Trace Nature Preserve in September 2016. The study site is located in Lamar County, Mississippi, just west of Hattiesburg, MS. Stem densities of I. glabra were collected once before the prescribed burn and twice after the prescribed burn at 2 month and 9 month …

Optimizing The Use Of A Liquid Handling Robot To Conduct A High Throughput Forward Chemical Genetics Screen Of Arabidopsis Thaliana, B. Kirtley Amos, Victoria G. Pook, Seth Debolt

Horticulture Faculty Publications

Chemical genetics is increasingly being employed to decode traits in plants that may be recalcitrant to traditional genetics due to gene redundancy or lethality. However, the probability of a synthetic small molecule being bioactive is low; therefore, thousands of molecules must be tested in order to find those of interest. Liquid handling robotics systems are designed to handle large numbers of samples, increasing the speed with which a chemical library can be screened in addition to minimizing/standardizing error. To achieve a high-throughput forward chemical genetics screen of a library of 50,000 small molecules on Arabidopsis thaliana (Arabidopsis), protocols using a …

Comparative Study Of Photosynthesis Rates Between Native Red Maple And Invasive Norway Maple In The Eastern Deciduous Forest, Evan M. Bourtis, Lindsey R. Heckman

The Review: A Journal of Undergraduate Student Research

Invasive species, such as the Norway Maple, are often able to outcompete native species, such as the Red Maple by performing more efficiently in the environment compared to the native species. In this study, we examined if the Norway maple was able to outcompete the Red Maple in the Eastern Deciduous Forest because the Norway Maple had a higher rate of photosynthesis. The study found that the Norway Maple leaves had a slightly higher rate of carbon dioxide consumption than Red Maple leaves and that the Red Maple leaves had a higher rate of oxygen production compared to the Norway …

Roles Of Phospholipases And Ribosomal S6 Kinase In Lipid Remodeling And Growth In Arabidopsis Response To Phosphate Deprivation, Yuan Su

Dissertations

Phosphate (Pi) is one of three macronutrients for plants, which is vital for plant growth and development. Understanding the mechanism by which plants respond and adapt to Pi deficiency not only unveils functions of genes and pathways involved, but also provides potential tools to manipulate crops to better stand Pi stress in low Pi-containing lands. One of the significant metabolic changes in plants under Pi starvation is the membrane lipid remodeling that converts Pi-containing lipids such as phospholipids to Pi-free lipids, such as glycolipids. To elucidate the metabolism and regulation of lipid remodeling, this dissertation characterizes the role of two …

Plant Biodiversity In The Face Of Climate Change: What Will Become Of Coastal Endemic Species?, Nila Le

Creative Activity and Research Day - CARD

How will longitudinally constrained coastal flora fare in the face of rapid anthropogenic climate change and disturbance? Coastal communities pose a unique problem for climate change and its associated risks. Species that are concentrated along the coast are naturally vulnerable to the influence of harsh abiotic ecology, such as coastal erosion and high salt concentrations. In addition, analogous to montane species-habitat interactions, coastal communities may be “pushed” off the coast edge as a result of tracking preferred climate in the face of climate variability and sea level rise. This can be problematic for species that cannot disperse quickly enough to …

Clarireedia: A New Fungal Genus Comprising Four Pathogenic Species Responsible For Dollar Spot Disease Of Turfgrass, Catalina Salgado-Salazar, Lisa A. Beirn, Adnan Ismaiel, Michael J. Boehm, Ignazio Carbone, Alexander I. Putman, Lane P. Tredway, Bruce B. Clarke, Jo Anne Crouch

Department of Plant Pathology: Faculty Publications

Dollar spot is one of the most destructive and economically important fungal diseases of amenity turfgrasses. The causal agent was first described in 1937 as the ascomycete Sclerotinia homoeocarpa. However, the genus-level taxonomic placement of this fungus has been the subject of an ongoing debate for over 75 y. Existing morphological and rDNA sequence evidence indicates that this organism is more appropriately placed in the family Rutstroemiaceae rather than the Sclerotiniaceae. Here we use DNA sequence data from samples of the dollar spot fungus and other members of the Rutstroemiaceae (e.g. Rutstroemia, Lanzia, Lambertella) collected throughout the world to determine …

2018 2nd Place: Identifying The Effectiveness Of Plant Extracts For Treating Biofilms Of Escherichia Coli And Myxococcus Xanthus, Micah Burton, Akeisha Belgrave, Rachel Fogle

Harrisburg University Research Symposium (2018 & 2019)

Antibiotic resistance is a topic that is of growing concern in the field of medicine. Antibiotics act as growth blockers or act as toxins, killing the organism they affect. These biological weapons generate selective pressure leading to the current antibiotic crisis. This selective pressure causes resistant organisms to begin to emerge and over generations antibiotic resistance can develop and be spread among a bacterial population.

One of the key factors contributing to antibiotic resistance in bacteria is the ability for some bacteria to form and shield themselves within biofilms. Biofilms are masses of bacteria protected by a polysaccharide/ extracellular DNA …

Speciation Of Lead, Chromium, Cadmium, Copper And Zinc In Sediments And Plants Along Msimbazi River In Dar Es Salaam, Tanzania, Faustin N Ngassapa, Othman C Othman, David Mihayo, Kessy F Kilulya

Tanzania Journal of Science

The speciation of lead, chromium, cadmium, copper and zinc in sediments and plants (pumpkin) along Msimbazi River in Dar es Salaam were determined using Atomic Absorption Spectrophotometry.  Results in sediments indicated that the heavy metal contents (mg/kg) in the form of total trace metals ranged from 50.34 to 161.63 for Pb, 68.38 to 501.85 for Zn, 18.43 to 66.61 for Cu, 20.93 to 76.46 for Cr and BDL to 0.23 for Cd. The contents (mg/kg) in the form of metals bound to organic matter ranged from 18.24 to 46.58 for Pb, 27.64 to 228.62 for Zn, 3.55 to 16.76 for …

The Plant Species Composition, Diversity And Natural Regeneration Of Indigenous Trees In The Disturbed Ruvu South Forest Reserve, Tanzania, Cosmas Mligo

Tanzania Journal of Science

Ruvu Forest Reserve is among coastal forests in Tanzania that has been impacted by the increased anthropogenic activities. It was determined the plant species composition, diversity and indigenous trees regeneration growth size structure in the degraded Ruvu South Forest. Transect method was used to collect data that were treated using t-test. A total of 110 plant species distributed among 38 families were recorded such that Holarrhena pubescens, Hymenocardia ulmoides, Millettia micans, Ochna mossambicensis, Pseudolachnostylis maprouneifolia and Strychnos madagascariensis were the most common trees in moderately disturbed site, whereas Albizia versicolor, Pteleopsis myrtifolia, Pterocarpus angolensis, Antiaris toxicaria, Diplorhynchus condylocarpon and Terminalia …

Application Of Regression Model To Identify A Parameter That Best Defines Species Diversity In The Coastal Forests Of Tanzania, Cosmas Mligo

Tanzania Journal of Science

Coastal forests of Tanzania are diverse in plant species that make them included as part of the 34 world biodiversity hotspots. This study aimed atdetermining plant species diversity, richness, and evenness as well as to identify the parameter that best defines plant species diversity in the three coastal forests; namely Zaraninge, Kazimzumbwi and Pande. Transect method was used for vegetation data collection and subjected to Analysis of variance and regression techniques. The plant species composition among forests ranged between 75 and 146 with a significantly lower diversity index in Zaraninge (2.057 ± 0.112) than those in Pande (2.415 ± 0.022) …

Similarity Coefficients Influence The Delimitation Of Species In The Genus Aloe L. (Xanthorrhoeaceae), Halima Amir, Mkabwa Manoko

Tanzania Journal of Science

The present study was designed to establish the influence of coefficients indices in delimiting species using phenetic approach based on morphological data. Data were collected from thirty nine Aloe species described in Flora of Tropical East Africa. A total of forty two qualitative and quantitative characters were compiled from 83 specimens of aloes. Ten coefficient indices were tested. Data were analysed using UPMA approach of PAST software. The analyses confirmed that, truly coefficient of indices influenced the resulting classification. Of the 10 coefficients used only three produced 36-38 of the 39 species. Almost a third produced less than ten species-specific …

Pengaruh Minyak Cengkeh Dan Jenis Kemasan Terhadap Mutu Benih Dua Kultivar Kacang Hijau (Vigna Radiata (L.) R. Wilczek) Setelah Periode Simpan, Sumadi, Anne Nuraini, Erni Suminar, Siti Sarah Rubaekah, Muhamad Alvianto

Jurnal Kultivasi

Seed storage is one of the efforts to maintain seed quality until the seed is ready to be planted. Some factors that influence seed quality after the storage period are seed storage pest attack, packaging type and seed charac-teristics of each cultivar. The objectives of the experiment was to determine the combination of dosage of clove oil, packaging type and mung bean cultivar. This research consisted of two series of experiments: to study the effectiveness of a combination of clove oil dosage with cultivars and tested combinations of packaging types with two mung bean cultivars. The first experiment was conducted …

Evaluating Effects Of Gene Mutation And Light Intensity On Arabidopsis Thaliana Development, Carolanne Bekus

Student Scholar Showcase

The completion of sequencing Arabidopsis thaliana’s genome has led to the next crucial challenge of determining gene function in these plants. A. thaliana is a model organism often compared to commercial crops. The discovery of gene function within these plants will aid in giving insight on how gene function can affect commercial crop production. Presented here is an analysis comparing wild-type Columbia (Col-O), to single gene mutants when knocking-out transcriptional factors VPI/ABI3-like 1 (val1) and basic region/leucine zipper motif (bZIP). These single gene mutations may affect several traits that in turn can result in morphological changes and/or …

Water Capacity Of Paramo Soils, Rafael Robert

Independent Study Project (ISP) Collection

The pȧramo ecosystems in the high Ecuadorian Andes are grasslands characterized by challenging abiotic factors such as low temperatures and high solar radiation. Another key feature of pȧramos is the humidity and water availability in the ecosystem. Pȧramos are very important to the hydrology of the inter-Andean valley because they are water reserves that distribute fresh water to lower elevations. These hydrologic properties are made possible by the porous volcanic ash soils formed by the volcanic arc along the mountain range. This study is focused in the region of Chimborazo approximately 20 km from Riobamba the capitol city of the …

Responses Of Marigold Cultivars To Saline Water Irrigation, Youping Sun, Genhua Niu, Christina Perez, H. Brent Pemberton, James Altland

Plants, Soils, and Climate Faculty Publications

Marigolds (Tagetes sp.) are ornamental plants with fine-textured, dark green foliage, and yellow, orange, or bicolored flowers. The relative salt tolerance of eight marigolds [‘Discovery Orange’, ‘Discovery Yellow’, ‘Taishan Gold’, ‘Taishan Orange’, and ‘Taishan Yellow’ African marigold (Tagetes erecta); ‘Hot Pak Gold’, ‘Hot Pak Orange’, and ‘Hot Pak Yellow’ French marigold (Tagetes patula)] was evaluated in a greenhouse experiment. Plants were irrigated weekly with nutrient solution at an electrical conductivity (EC) of 1.2 dS·m⁻¹ (control) or saline solutions at an EC of 3.0 or 6.0 dS·m⁻¹ (EC 3 or EC 6). Marigold plants …