Jaap D. Janse

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The potential of Biological Soil Disinfestation (BSD) to control potato brown rot, caused by Ralstonia solanacearum race 3 biovar 2, was investigated. BSD involves the induction of anaerobic soil conditions by increasing microbial respiration through incorporation of fresh organic amendments (here: grass or potato haulms) and by reducing re-supply of oxygen(More)
The population dynamics of the brown rot bacterium Ralstonia (Pseudomonas) solanacearum in surface water of two selected water-areas were monitored over a two-year period. In some cases during summer, high bacterial numbers (up to 106 cfu l−1) were observed. In a host plant survey a few plants of stinging nettle (Urtica dioica) were found to be a natural(More)
A polyphasic approach was used to describe the phylogenetic position of 22 chitinolytic bacterial isolates that were able to grow at the expense of intact, living hyphae of several soil fungi. These isolates, which were found in slightly acidic dune soils in the Netherlands, were strictly aerobic, Gram-negative rods. Cells grown in liquid cultures were(More)
The effect of temperature and the availability of nutrients on the transition of spiral Campylobacter jejuni cells to coccoid forms was investigated. Ageing of spiral C. jejuni cells in either nutrient-poor or nutrient-rich environments resulted in the formation of nonculturable coccoid cells at 4, 12, and 25 degrees C after different periods, with the(More)
During the last two decades bacterial strains associated with necrotic leaf spots of pepper and tomato fruit spots were collected in Serbia. Twenty-eight strains isolated from pepper and six from tomato were characterized. A study of their physiological and pathological characteristics, and fatty acid composition analysis revealed that all of the strains(More)
Within a nitrate-reducing bacterial community, a niche differentiation between denitrifying and nitrate ammonifying bacteria may be determinated by a complex of environmental parameters, such as the availability of carbon, nitrate, and oxygen. Hence, oxygen- and carbon-releasing aerenchymatous plants may affect the composition of the nitrate-reducing(More)
Immunofluorescence microscopy is a very sensitive serological test which harnesses both the power of antibodies to bind to targets along with the use of the fluorescence microscope to visualise the structures to which they bind. Antibody binding is visualised by the fluorescent emission from a marker molecule bound to the antibody. The technique is of(More)
At present, much attention is being given to the potential of plant pathogens, including plant-pathogenic bacteria, as biological weapons/bioterror weapons. These two terms are sometimes used interchangeably and there is need for care in their application. It has been claimed that clandestine introduction of certain plant-pathogenic bacteria could cause(More)
Stenotrophomonas maltophilia was isolated from the rhizosphere of eggplant in the Nile Delta of Egypt, and its antagonistic potential against Ralstonia solanacearum race 3 biovar 2, the causal agent of potato brown rot, was in vitro evaluated on KB agar medium and in vivo on potato plants. In vitro, four isolates of S. maltophilia (PD3531, PD3532, PD3533,(More)
During the past few years, Ralstonia (Pseudomonas) solanacearum race 3, biovar 2, was repeatedly found in potatoes in Western Europe. To detect this bacterium in potato tissue samples, we developed a method based on fluorescent in situ hybridization (FISH). The nearly complete genes encoding 23S rRNA of five R. solanacearum strains and one Ralstonia(More)