EFFECTIVENESS OF DIFFERENT DOSES OF HETERORHABDITIS BACTERIOPHORA AGAINST POPILLIA JAPONICA 3rd INSTARS: LABORATORY EVALUATION AND FIELD APPLICATION

The recent introduction into Italy of the Japanese beetle (Popillia japonica Newman) has triggered new research on biological control agents aimed at limiting the spread of this alien pest. From the scientific literature it is known that the entomopathogenic nematode Heterorhabditis bacteriophora Poinar is very effective against P. japonica. Here we present a laboratory test comparing the lethal activity at three different concentrations of the commercial product Nematop (R) (CBC, Europe), containing H. bacteriophora, against P. japonica 3rd instars. The results showed that the lower dose (25 IJs/cm(2)) maintained an effectiveness of about 90%, thus not differing on the whole from the values of the other concentrations. Afterwards, this dose was tested in the field both in the spring and summer with grub killing values of 25 and 45%, respectively.