While most commonly associated with prokaryotes, horizontal gene transfer (HGT) can also have a significant influence on the evolution of microscopic eukaryotes. Systematic analysis of HGT in the genomes of the oomycetes, filamentous eukaryotic microorganisms in the Stramenopiles-Alveolates-Rhizaria (SAR) supergroup, has to date focused mainly on intradomain transfer events between oomycetes an...

Composts are known for their suppressive properties toward many different seed- and root-infecting pathogens and diseases. Although disease and pathogen suppression induced by composts is believed to be mediated by microbial activities, the nature of the microbial species and processes responsible for suppressiveness remain unknown. We demonstrated previously that seed-colonizing microbial cons...

Soil-borne pathogens are a key component of the belowground community because of the significance of their ecological and socio-economic impacts. However, very little is known about the complexity of their distribution patterns in natural systems. Here, we explored the patterns, causes and ecological consequences of spatial variability in pathogen abundance in Mediterranean forests affected by ...

Twenty-eight isolates of Pythium insidiosum and P. destruens from Asia, Australia and the Americas were compared on the basis of restriction fragment-length polymorphisms of the amplified ribosomal intergenic spacer. Comparison of band profiles yielded three distinct clusters and an isolate that did not fall into any of the clusters. Cluster I consisted of 16 isolates, all from the Americas (Co...

AIMS Four well-described strains of Pseudomonas fluorescens were assessed for their effect on pea growth and their antagonistic activity against large Pythium ultimum inocula. METHODS AND RESULTS The effect of Pseudomonas strains on the indigenous soil microflora, soil enzyme activities and plant growth in the presence and absence of Pythium was assessed. Pythium inoculation reduced the shoot...

ABSTRACT A series of laboratory tests were conducted to investigate potential effects of fungus gnat (Bradysia impatiens) feeding damage on susceptibility of geranium seedlings (Pelargonium x hortorum) to infection by the root rot pathogen Pythium aphanidermatum. Effects were compared with those from similar tests in which the seedlings were mechanically wounded by severing the root tip with a ...