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

Digital Commons Network

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

PDF

Plant Sciences

Theses/Dissertations

Louisiana State University

Bacterial panicle blight

Articles 1 - 7 of 7

Full-Text Articles in Entire DC Network

Development Of Alternative Materials And Strategies For Enhancing Rice Health, Jobelle S. Bruno Apr 2022

Development Of Alternative Materials And Strategies For Enhancing Rice Health, Jobelle S. Bruno

LSU Master's Theses

Bacterial panicle blight (BPB) and sheath blight (ShB) are economically important diseases of rice (Oryza sativa) in Louisiana and other rice-growing regions around the world. However, there are challenges in the current disease management practices for these diseases. Thus, the main goal of this study is to identify new materials and their application methods that effectively suppress BPB and ShB. To achieve this goal, we evaluated the effect of various materials and application methods against the rice diseases. In 2020 and 2021, various materials, such as ascorbic acid (AA), N-acetylcysteine, chitosan, the avirulent strain of Burkholderia glumae 257sh-1 …


Development Of Biological Tools To Promote Rice Health And Growth, Ateet Maharjan Jul 2019

Development Of Biological Tools To Promote Rice Health And Growth, Ateet Maharjan

LSU Master's Theses

Sheath blight (ShB - caused by Rhizoctonia solani) and bacterial panicle blight (BPB - caused by Burkholderia glumae) are economically important rice diseases in Louisiana and other rice-growing regions. Fungicides and oxolinic acid are used to manage ShB and BPB, respectively, but these chemical methods are not sustainable economically and ecologically. Besides diseases, plant utilizable nitrogen (N) in the soil is inadequate for optimum crop yield, leading to the use of inorganic fertilizers and making agriculture less sustainable. To develop alternative biological control methods for protecting rice plants from diseases, rice-associated bacteria were screened based on their antagonistic …


Genetics And Genomics Studies Of Rice Disease Resistance And Development Of Alternative Disease Management Methods For Bacterial Panicle Blight And Sheath Blight, Bishnu Kumar Shrestha Jan 2014

Genetics And Genomics Studies Of Rice Disease Resistance And Development Of Alternative Disease Management Methods For Bacterial Panicle Blight And Sheath Blight, Bishnu Kumar Shrestha

LSU Doctoral Dissertations

Bacterial panicle blight (BPB) and sheath blight (SB), caused by the bacteria Burkholderia glumae and B. gladioli, and the fungus Rhizoctonia solani, respectively, are two major rice diseases in southern rice growing regions of US. No completely resistant rice cultivars have been identified for these diseases. However, a medium-grain cultivar, Jupiter, showed partial resistance to BPB. In order to understand the mechanisms of rice resistance against BPB and SB, rice genetics and genomics studies have been conducted. Alternative methods to suppress BPB and SB were also studied. Broad-sense heritability and correlations were calculated for the traits, BPB and SB disease …


Characterization Of A Σ54-Dependent Response Regulator, Tepr, In The Rice-Pathogenic Bacterium Burkholderia Glumae And Development Of Biocontrol Strategies For Bacterial Panicle Blight Of Rice, Surendra Osti Jan 2014

Characterization Of A Σ54-Dependent Response Regulator, Tepr, In The Rice-Pathogenic Bacterium Burkholderia Glumae And Development Of Biocontrol Strategies For Bacterial Panicle Blight Of Rice, Surendra Osti

LSU Master's Theses

Bacterial panicle blight, caused by Burkholderia glumae, is a major bacterial disease of rice in Louisiana. This bacterium contains several virulence factors required for disease development such as toxoflavin, lipase and flagella. In a genome-wide search for regulatory factors related to the virulence of B. glumae, tepR was identified as a negative regulator for toxoflavin production and found to encode a sigma 54-dependent response regulator. TepR is homologous to LuxO, a quorum-sensing signaling component of Vibrio spp. A markerless tepR deletion mutant of B. glumae 336gr-1, LSUPB401, produced more toxoflavin and showed higher lipase and protease activities compared to the …


A Genetic Study On The Virulence Mechanism Of Burkholderia Glumae And, Rice Resistance To Bacterial Panicle Blight And Sheath Blight, Hari Sharan Karki Jan 2013

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 …


Comparative Genomics, Transcriptome Analysis And Characterization Of Selected Regulatory Genes Of Burkholderia Glumae, Felix Francis Jan 2012

Comparative Genomics, Transcriptome Analysis And Characterization Of Selected Regulatory Genes Of Burkholderia Glumae, Felix Francis

LSU Master's Theses

Burkholderia glumae is the primary causal agent of bacterial panicle blight of rice, which is becoming a major threat to global rice production. The genome of a highly virulent B. glumae strain, 336gr-1 that was isolated from rice in Louisiana, was sequenced to better understand the genome-scale characteristics, particularly that of its pathogenicity. Comparative genomic analyses with another strain, BGR1 that was isolated from Korea, revealed several unique regions present in the genomes of these two geographically separated phytopathogenic bacteria. Genome plasticity, primarily caused by a horizontal gene transfer, was observed in these closely related strains of Burkholderia that are …


Identification Of Bacterial Pathogens Causing Panicle Blight Of Rice In Louisiana, Xianglong Yuan Jan 2004

Identification Of Bacterial Pathogens Causing Panicle Blight Of Rice In Louisiana, Xianglong Yuan

LSU Master's Theses

Four hundred and two bacterial isolates isolated on the semi-specific S-PG medium from diseased rice tissues showing symptoms of panicle blighting. These isolates were purified using serial dilution in sterile water and replating on S-PG medium. A total of 420 single isolates were obtained. These isolates were subjected to pathogenicity tests on rice (Oryza sative L. cv. Cypress). Based on these tests, 339 isolates were used in BiologTM tests and identified to the species level. Bacterial strains from 39 species in 16 genera were identified, including 52 isolates representing15 Pseudomonas species and 261 isolates representing six Burkholderia species. The remaining …