Search results for "RALSTONIA SOLANACEARUM"

The combined action of 9 lipoxygenase and galactolipase is sufficient to bring about programmed cell death during tobacco hypersensitive response

2005

International audience; Oxylipins, derived from fatty acid hydroperoxides (FAHs), are thought to play different roles during plant pathogen interactions. During hypersensitive response (HR) some of them serve as signals necessary for defence gene activation whereas others could contribute to pathogen killing or could participate in the execution of plant programmed cell death (PCD) associated with this resistance. In order to address the role of these compounds in the latter process, we have closely observed lipid peroxidation, the first step of this metabolic pathway, under different situations which led either to accelerated or inhibited HR cell death. The oxidative process has been studi…

Bacteriophage-Based Bacterial Wilt Biocontrol for an Environmentally Sustainable Agriculture

2017

Bacterial wilt diseases caused by Ralstonia solanacearum, R. pseudosolanacearum and R. syzygii subsp. indonesiensis (former R. solanacearum species complex) are among the most important plant diseases worldwide, severely affecting a high number of crops and ornamentals. Difficulties of bacterial wilt control by non-biological methods are related to effectiveness, bacterial resistance and environmental impact. Alternatively, a great many biocontrol strategies have been carried out, with the advantage of being environmentally friendly. Advances in bacterial wilt biocontrol include an increasing interest in bacteriophage-based treatments as a promising re-emerging strategy. Bacteriophages agai…

Engineering of a bacterial tyrosinase for improved catalytic efficiency towards D-tyrosine using random and site directed mutagenesis approaches

2013

The tyrosinase gene from Ralstonia solanacearum (GenBank NP518458) was subjected to random mutagenesis resulting in tyrosinase variants (RVC10 and RV145) with up to 3.2-fold improvement in kcat, 5.2-fold lower Km and 16-fold improvement in catalytic efficiency for D-tyrosine. Based on RVC10 and RV145 mutated sequences, single mutation variants were generated with all variants showing increased kcat for D-tyrosine compared to the wild type (WT). All single mutation variants based on RV145 had a higher kcat and Km value compared to the RV145 and thus the combination of four mutations in RV145 was antagonistic for turnover, but synergistic for affinity of the enzyme for D-tyrosine. Single muta…

PERBANDINGAN DAYA HAMBAT BAKTERI Pseudomonas fluorescens ASAL TOMAT, KEDELAI, DAN JAGUNG TERHADAP Ralstonia solanacearum SECARA IN VITRO

2018

<em>Inhibition of Pseudomonas fluorescens isolates the origin of tomato, soybean and corn against Ralstonia solanacearum tested using a completely randomized design (CRD).        P. fluorescens growth was measured at King's B medium by way of suspension antagonist put on filter paper of 0.5 cm in diameter. Inhibition of P. fluorescens is done by placing the antagonist suspension of 0.5 cm diameter filter paper on NA media that has been deployed R. solanacearum. The results showed that: (a) the growth of P. fluorescens origin of tomato, soybean and corn on King's B media were not significantly different, (b) the inhibition of P. fluorescens isolates against R. solanacearum not signific…

Biocontrol of the Major Plant Pathogen Ralstonia solanacearum in Irrigation Water and Host Plants by Novel Waterborne Lytic Bacteriophages

2019

Three new lytic bacteriophages were found to effectively control the pathogen Ralstonia solanacearum, a quarantine bacterium in many countries, and causative agent of bacterial wilt, one of the most important vascular plant diseases. Bacterial wilt management has been carried out with fluctuating effects, suggesting the need to find alternative treatments. In this work, three lytic phages were isolated from environmental water from geographically distant regions in Spain. They proved to specifically infect a collection of R. solanacearum strains, and some of the closely related pathogenic species Ralstonia pseudosolanacearum, without affecting non-target environmental bacteria, and were abl…

Survival strategies and pathogenicity of Ralstonia solanacearum phylotype II subjected to prolonged starvation in environmental water microcosms

2008

Survival strategies exhibited over 4 years by Ralstonia solanacearum phylotype (ph) II biovar (bv) 2 in environmental water microcosms were examined. The bacterium is a devastating phytopathogen whose ph II bv 2 causes bacterial wilt in solanaceous crops and ornamental plants. Outbreaks of the disease may originate from dissemination of the pathogen in watercourses, where it has to cope with prolonged nutrient limitation. To ascertain the effect of long-term starvation on survival and pathogenicity of R. solanacearum in natural water microcosms, survival experiments were conducted. Microcosms were prepared from different sterile river water samples, inoculated separately with two European s…

Innovation in bacteriophage-based biocontrol of the plant pathogen ralstonia solanacearum through irrigation water

2017

In silico evaluation of molecular probes for detection and identification of Ralstonia solanacearum and Clavibacter michiganensis subsp. sepedonicus.

2004

Ralstonia solanacerum and Clavibacter michiganensis subsp. sepedonicus are the two most relevant bacterial pathogens of potato for which a large number of molecular diagnostic methods using specific DNA sequences have been developed. About one hundred oligonucleotides have been described and thoroughly tested experimentally. After having compiled and evaluated all these primers and probes in silico to check their specificity, many discrepancies were found. A detailed analysis permitted the recognition of different possible reasons for such discrepancies: sequencing errors in public sequences, wrong supposed specificity (sometimes due to more recent sequences than the oligonucleoticles being…

Survival ofRalstonia solanacearum Biovar 2 in River Water: Influence of Water Microbiota

2008

Current Technologies for Pseudomonas spp. And Ralstonia solanacearum Detection and Molecular Typing

2008

Standard protocols for detection of phytopathogenic Pseudomonas spp. and Ralstonia solanacearum in plant material, soil, water or other sources, often still rely on the isolation of bacterial colonies on appropriate media, and/or on the use of serological techniques. However, over the last several years, molecular techniques, mainly based on PCR methods after extraction of nucleic acids from samples, have improved enough to allow a more rapid, reliable detection of these bacteria. When maximum accuracy is required the use of multiple techniques in an integrated approach is advised. Other promising technologies like flow cytometry, electronic nose or microarrays are emerging due to the need …