Assessment of Pathogenicity and Infectivity of Heterorhabditis Bacteriophora Against Galleria Mellonella

Entomopathogenic nematodes (EPNs) belonging to the families Steinernematidae and Heterorhabditidae are widely recognized as effective biological control agents against insect pests of agricultural importance. In the present study, entomopathogenic nematodes were isolated from soil samples collected in the Vere Valley, Tbilisi, Georgia, and their pathogenicity and infectivity were evaluated under laboratory conditions using Galleria mellonella larvae as a model host. Isolation was conducted using an insect baiting technique, followed by nematode recovery through a modified White trap method. Larvae were exposed to a standardized dose of eight infective juveniles per individual. Successful infection by Heterorhabditis spp. was confirmed by the appearance of characteristic brick-red coloration in larval cadavers, absence of putrefactive odor, and preservation of cadaver integrity. The results demonstrated high infectivity and rapid host mortality within 48–72 hours. These findings support the potential application of entomopathogenic nematodes as environmentally friendly alternatives to chemical pesticides and highlight their relevance in integrated pest management programs.