Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Entire DC Network

Evolutionary Relationships Among Fungal Soybean Pathogens And Molecular Marker Development In The Genus Cercospora, Sebastian Albu Jan 2015

Evolutionary Relationships Among Fungal Soybean Pathogens And Molecular Marker Development In The Genus Cercospora, Sebastian Albu

LSU Doctoral Dissertations

Cercospora leaf blight (CLB) and purple seed stain (PSS) are common soybean diseases in the Gulf South of the United States (USA). For nearly a century, Cercospora kikuchii has been considered as the only pathogen causing these diseases. However, previous reports of genetic diversity among isolates collected throughout Louisiana suggested the presence of multiple lineages or species. Recent systematic studies classified species of Cercospora using a taxonomic system based on phylogenetic analysis of five nuclear loci (legacy genes). Using a similar approach, cercosporoid fungi tentatively identified as C. kikuchii were evaluated along with 53 other species of Cercospora. No …


Study Of Factors Affecting Growth And Development Of Narrow Brown Leaf Spot Of Rice Caused By Cercospora Janseana (Racib.) O. Const., Kirandeep Kaur Mani Jan 2015

Study Of Factors Affecting Growth And Development Of Narrow Brown Leaf Spot Of Rice Caused By Cercospora Janseana (Racib.) O. Const., Kirandeep Kaur Mani

LSU Doctoral Dissertations

Studies evaluated the effects of planting date, cultivar susceptibility, fungicide application timing, nitrogen management, and tillage practices on the severity of narrow brown leaf spot of rice (NBLS) caused by Cercospora janseana. All factors evaluated affected NBLS severity. The mid-April planted rice had less NBLS as compared to mid-May, late planted rice. Propiconazole fungicide (Tilt) application at panicle initiation or early boot stage was found equally effective in terms of disease reduction in mid-April planting while panicle initiation stage was the best time to apply fungicide in the late planting (mid-May). Early onset and higher severity of NBLS was observed …


Effects Of Minor Elements On Cercospora Kikuchii, Cercospora Leaf Blight And Rust On Soybeans, Brian Michael Ward Jan 2015

Effects Of Minor Elements On Cercospora Kikuchii, Cercospora Leaf Blight And Rust On Soybeans, Brian Michael Ward

LSU Master's Theses

Soybean (Glycine max) is one of the most widely grown crops in the world. Many pathogens attack soybeans, but of particular importance to tropical and subtropical areas such as Louisiana is Cercospora leaf blight (CLB). This disease is caused by the fungus Cercospora kikuchii and favored by high temperatures. This fungus utilizes a toxin, cercosporin, as its primary pathogenicity factor. Soybean rust (SBR), caused by Phakopsora pachyrhizi, is another common disease that occurs in Louisiana under cooler environmental conditions of spring and fall. Both diseases occur regularly in Louisiana and may result in severe yield losses. Cercospora kikuchii has recently …


Genetic And Transcriptomic Analyses Of The Rice Pathogenic Bacterium, Burkholderia Glumae, Reveal The Important Roles Of The Regulatory Gene, Tepr, For Bacterial Survival In Environmental Stresses, Jingyu Peng Jan 2015

Genetic And Transcriptomic Analyses Of The Rice Pathogenic Bacterium, Burkholderia Glumae, Reveal The Important Roles Of The Regulatory Gene, Tepr, For Bacterial Survival In Environmental Stresses, Jingyu Peng

LSU Master's Theses

Burkholderia glumae causes bacterial panicle blight in rice by producing the phytotoxin, toxoflavin, as a major virulence factor. Production of toxoflavin is negatively regulated by tepR, which encodes a sigma 54-dependent response regulator. In order to gain insights into the comprehensive biological functions of tepR, the genome-wide transcriptional profile dependent on tepR was analyzed through comparative transcriptome analysis between a tepR defective mutant and the wild-type strain, resulting in the identification of 238 differentially expressed genes (DEGs). Gene Ontology (GO) enrichment analysis indicated that genes involved in flagella assembly and stress response were highly enriched in tepR defective strain. Kyoto …