Biodiversity of entomoparasitic and entomopathogenic nematodes in Italy

Due to the renewed interest in entomopathogens, EPNs in particular, and to important research projects in which we have been involved, in the last ten years several investigations were carried out on the distribution and biodiversity of entomoparasitic and entomopathogenic (steinernematid and heterorhabdtid) nematodes in North and South Regions of Italy. More than 8000 samples were collected from 850 localities and more than 100 of them yielded entomoparasitic or/and entomopathogenic specimens. A mapping of EPN’s distribution in Italy was update with new indigenous entomoparasitic and entomopathogenic strains some of which are currently being studied in depth because they could be new species (which would be added to the 13 species already known for Italy: Heterorhabditis bacteriophora, H. downesi, H. megidis, Steinernema feltiae, S. affine, S. kraussei, S. apuliae, S. ichnusae, S. carpocapsae, S. vulcanicum, S. arenarium, Oscheius onirici, O. myriophilus and Hexamermis sp.). Steinernematids are more widespread than heterorhabditids and S. feltiae, S. carpocapsae and H. bacteriophora are the most commonly encountered species. Sampling sites were grouped into 11 habitats: uncultivated land, orchard, field, seacoast, pinewood, broadleaf wood, grasslands, river and lake borders, caves, salt pan and moist zones. The habitat preferences of each species were assessed and, except for the three dominant species, S. feltiae, S. carpocapsae and H. bacteriophora, EPN’s occurrence tends to be correlated with a specific vegetation habitat and soil type.