The specific gravity of spores of Pasteuria penetrans collected from Meloidogyne arenaria was found to be around 1.28. Increasing the sucrose concentration used for the extraction of Pratylenchus scribneri from a specific gravity of 1.14 to 1.26 led to the recovery of higher numbers of specimens filled with spores of Pasteuria sp. (P </= 0.05). The numbers of spore-filled specimens of Hoplolaim...

The last ten years have witnessed increasing interest in host-pathogen interactions involving invertebrate hosts. The invertebrate innate immune system is now relatively well characterised, but in a limited range of genetic model organisms and under a limited number of conditions. Immune systems have been little studied under real-world scenarios of environmental variation and parasitism. Thus,...

Protein-encoding and 16S rRNA genes of Pasteuria penetrans populations from a wide range of geographic locations were examined. Most interpopulation single nucleotide polymorphisms (SNPs) were detected in the 16S rRNA gene. However, in order to fully resolve all populations, these were supplemented with SNPs from protein-encoding genes in a multilocus SNP typing approach. Examination of individ...

The bacteria Pasteuria spp. have been identified as among the most promising of several microbial organisms currently under investigation as biological control agents of plant-parasitic nematodes. As part of our goal to develop methods to discriminate isolates of Pasteuria penetrans with different host preferences, we investigated the potential of developing antibody probes to identify endospor...

Endospores of Pasteuria penetrans were evaluated for their vertical distribution in field soil and their downward movement through soil in the laboratory. In the field trial, the number of endospores attached to second-stage juveniles (J2) of Meloidogyne arenaria race 1 varied greatly in different soil depths. There were higher percentages of J2 with endospores attached in former weed fallow pl...

Attachment of relatively low numbers of endospores from two isolates of Pasteuria spp. to several species of nematodes was consistently achieved in 2-5 minutes with a centrifugation technique. The rate of attachment of Pasteuria penetrans at 10 endospores/0.1 ml/tube to second-stage juveniles (J2) of Meloidogyne javanica, M. incognita race 1, M. incognita race 3, and M. arenaria races 1 and 2 i...

The endospore and central core diameters of 69 isolates of Pasteuria spp. showed a relationship with the body wall thickness of their corresponding host nematodes. A relationship was also observed when cuticle and hypodermis layer data were derived from transmission electron microscopy micrographs. Principal component analysis and hierarchical cluster analysis based on endospore and central cor...