Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Burkholderia glumae (2)
- Reniform nematode (2)
- Aflatoxin (1)
- Asian Soybean Rust (1)
- Aspergillus flavus (1)
-
- Bacterial panicle blight (1)
- Biological control (1)
- Cercospora kikuchii (1)
- Clostridium spp (1)
- Coevolution (1)
- Cotton cultivar (1)
- DIGE (1)
- Desiccation tolerance (1)
- End rot (1)
- Fungicide (1)
- Fusarium (1)
- Geneological species concept (1)
- Glycine max (1)
- Host-pathogen interaction (1)
- Host-specificity (1)
- Immature kernels (1)
- Macrophomina phaseolina (1)
- Maize (1)
- Mass Spectrometry (1)
- Mutation (1)
- Pathogenicity (1)
- Phosphorus (1)
- Potassium (1)
- Quorum sensing (1)
- RNA-seq (1)
Articles 1 - 10 of 10
Full-Text Articles in Entire DC Network
Proteomics-Based Study Of Host-Fungus Interaction Between Soybean And Phakopsora Pachyrhizi Using Recombinant Inbred Line (Ril) Derived Sister Lines, Mala Ganiger
LSU Master's Theses
Phakopsora pachyrhizi, the causal agent of Asian soybean rust (ASR), has the potential to cause severe yield losses as all United States commercial soybean varieties are susceptible. In this study, 10 soybean recombinant inbred line (RIL) derived sibling lines of two populations (RN06-32-2 and RN06-16-1) were evaluated for differences in response to infection by P. pachyrhizi. These lines, which had previously shown differential responses to Florida soybean rust isolates, were evaluated using Louisiana soybean rust isolates under both detached leaf assay and greenhouse in planta inoculation conditions. Sibling lines showed significant differences in response to P. pachyrhizi infection under both …
A Novel System To Study Seed Recalcitrance And Dormancy - Comparative Proteomics Between Two Spartina Species, Yi Wang
LSU Doctoral Dissertations
Spartina alterniflora is a dominant salt marsh cordgrass along the U.S. Atlantic and Gulf coasts, and the species is widely used for wetland restoration in Louisiana. S. alterniflora seeds are shed dormant from the mother plant. However, long-term preservation of S. alterniflora seeds is challenging because the seeds are recalcitrant, losing viability when dried below 45% water content. In this dissertation, I investigated the following three aspects of S. alterniflora: recalcitrance, dormancy release by cold stratification and the effect of drying temperature on the critical water content. Comparative proteomics between S. alterniflora and orthodox, desiccation tolerant Spartina pectinata seeds identified …
The Influence Of Commerce Silt Loam Soil Texture On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Déborah Magalhães Xavier
The Influence Of Commerce Silt Loam Soil Texture On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Déborah Magalhães Xavier
LSU Master's Theses
Greenhouse and microplot studies were conducted to evaluate the influence of soil texture on reproduction and pathogenicity of Rotylenchulus reniformis (reniform nematode) on cotton. A 45 day duration greenhouse experiment confirmed the pathogenicity of an isolate of R. reniformis from Avoyelles Parish on Stoneville LA887 cotton. A series of greenhouse experiments were conducted with three geographic isolates of R. reniformis (identified as Avoyelles, Evangeline, and Rapides to indicate the Parish of origin) on Stoneville LA887, Stoneville 5288B2F, and Phytogen 375WF cotton growing in soils with varying textures for 60 days. Soil types with sand, silt, and clay contents ranging from …
Influence Of Soil Nutrients On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Herath Mudiyanselage Manjula Thaminda Kularathna
Influence Of Soil Nutrients On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Herath Mudiyanselage Manjula Thaminda Kularathna
LSU Master's Theses
Among the variety of pathogens of cotton (Gossypium hirsutum), nematodes play a major role in reducing yield. Across the U.S. cotton belt, millions of dollars are lost annually due to nematode infestation. In the Mid-South and Southeast United States, root-knot nematode (Meloidogyne incognita) and reniform nematode (Rotylenchulus reniformis) are responsible for the highest percentage of damage. Crop rotation and nematicides are currently the most commonly used management strategies for nematode management. Soil fertility, which has a direct effect on plant growth, is also known to influence disease severity. Therefore, soil fertility would be an additional factor to consider for management …
Sensitivity And Resistance Of Cercospora Kikuchii, Causal Agent Of Cercospora Leaf Blight And Purple Seed Stain Of Soybean, To Selected Fungicides, Paul Patrick Price, Iii
Sensitivity And Resistance Of Cercospora Kikuchii, Causal Agent Of Cercospora Leaf Blight And Purple Seed Stain Of Soybean, To Selected Fungicides, Paul Patrick Price, Iii
LSU Doctoral Dissertations
ABSTRACT Isolates of Cercospora kikuchii, the causal agent of Cercospora leaf blight (CLB) and purple seed stain (PSS), were used to determine baseline sensitivities to selected quinone outside inhibitor (QoI) and demethylation inhibitor (DMI) fungicides by conducting radial growth assays on fungicide-amended media. The effective concentration to inhibit 50% radial growth (EC50) for each isolate was calculated by linear interpolation of the dose-response relationship. All baseline distributions were non-normal with outliers towards the less sensitive ends of the spectra, and median EC50 values for azoxystrobin, pyraclostrobin, trifloxystrobin, flutriafol, propiconazole, and tetraconazole were 0.081, 0.013, 0.012, 0.273, 0.143, 1.47 µg/ml, respectively. …
Integrated Functional Anlaysis Of Quorum-Sensing In The Rice Pathogenic Bacterium Burkholderia Glumae, Ruoxi Chen
Integrated Functional Anlaysis Of Quorum-Sensing In The Rice Pathogenic Bacterium Burkholderia Glumae, Ruoxi Chen
LSU Doctoral Dissertations
Quorum sensing (QS) is a cell-to-cell communication mechanism that allows bacterial cells to collectively behave like a multicellular organism. It regulates the expression of toxoflavin, one of the major virulence factors of the rice pathogen, Burkholderia glumae. The QS system of B. glumae is mediated by the core genes, tofI and tofR. N-octanoyl-L-homoserine lactone, the primary QS signal molecule of B. glumae, is synthesized by tofI and binds to the cognate receptor tofR at the quorum point. However, tofI and tofR null mutants produce toxoflavin in certain growth conditions, indicating the presence of tofI- and tofR-independent pathways for toxoflavin production. …
A Genetic Study On The Virulence Mechanism Of Burkholderia Glumae And, Rice Resistance To Bacterial Panicle Blight And Sheath Blight, Hari Sharan Karki
A Genetic Study On The Virulence Mechanism Of Burkholderia Glumae And, Rice Resistance To Bacterial Panicle Blight And Sheath Blight, Hari Sharan Karki
LSU Doctoral Dissertations
Burkholderia glumae is a rice pathogenic bacterium that causes bacterial panicle blight. Some strains of this pathogen produce dark brown pigments when grown on the casamino-acid peptone glucose (CPG) agar medium. A pigment-positive and highly virulent strain of B. glumae, 411gr-6, was randomly mutagenized with mini-Tn5gus, and the resulting mini-Tn5gus derivatives showing altered pigmentation phenotypes were screened on CPG agar plates to identify the genetic elements governing the pigmentation of B. glumae. In this study, several positive and negative regulators, for the pigmentation of B. glumae were identified. During this study, a novel two-component regulatory system (TCRS) composed of the …
A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen
A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen
LSU Master's Theses
There are more than 7800 species of Pucciniales (rust fungi) described. Aeciospores and urediniospores of rust fungi are a food source for the larval stage of members of the fly genus Mycodiplosis, hence these could be of interest as potential biological control agents. Currently, Mycodiplosis contains 49 described species based on adult male morphology. A survey of 1,350 rust-infected plants from 44 countries was recently conducted to assess the occurrence of Mycodiplosis fly larvae across a broad spectrum of Pucciniales. Larvae were found on 261 collections from 25 countries. Statistical analyses explored the distribution of larvae in relation to host …
Potential Roles Of Wrky Transcription Factors In Resistance To Aspergillus Flavus Colonization Of Immature Maize Kernels, Jake Clayton Fountain
Potential Roles Of Wrky Transcription Factors In Resistance To Aspergillus Flavus Colonization Of Immature Maize Kernels, Jake Clayton Fountain
LSU Master's Theses
The infection and colonization of maize (Zea mays L.) by the necrotrophic fungal pathogen Aspergillus flavus results in contamination of kernel tissues with carcinogenic mycotoxins known as aflatoxins, resulting in severe economic losses as well as negative effects on human and animal health. Resistance to A. flavus is mediated by both inducible and constitutively expressed defense proteins; however the mechanism regulating the expression of these defenses is poorly understood. This study examined the potential roles of six maize WRKY transcription factors, ZmWRKY19, ZmWRKY21, ZmWRKY53, ZmWRKY53.1, ZmWRKY67, and ZmWRKY68, in regulating defense responses against …
Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva
Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva
LSU Master's Theses
Sweetpotato production in the southern United States is being threatened by a soft rot that develops in storage roots when fields are flooded and by an important post-harvest disease caused mainly by the fungi Fusarium solani and Macrophomina phaseolina. To identify the pathogens responsible for development of the soft rot, samples were collected from storage roots with soft rot from intentionally flooded fields and decayed tissue was streaked on plates of nutrient dextrose agar plus 0.05% cysteine and incubated anaerobically. Two distinct groups of Gram positive strict anaerobic bacteria were re-isolated from rotting storage roots. Endospores were observed in all …