Assessing the Pathogenicity of Two Bacteria Isolated from the Entomopathogenic Nematode Heterorhabditis indica against Galleria mellonella and Some Pest Insects

The entomopathogenic nematodes are parasites of insects and are associated with mutualist symbiosis enterobacteria of the genus ; these bacteria are lethal to their host insects. MOR03 was isolated from sugarcane soil in Morelos state, Mexico. The molecular identification of the nematode was confirmed using sequences of the ITS1-5.8S-ITS2 region and the D2/D3 expansion segment of the 28S rRNA gene. In addition, two bacteria HIM3 and NA04 strains were isolated from the entomopathogenic nematode. The genomes of both bacteria were sequenced and assembled de novo. Phylogenetic analysis was confirmed by concatenated gene sequence datasets as HIM3 (16S rRNA, 23S rRNA, , , and genes) and NA04 (16S rRNA, 23S rRNA and genes). MOR03 infects , , , and larvae with LC50 values of 1.4, 23.5, 13.7, and 21.7 IJs/cm², respectively, at 48 h. These bacteria are pathogenic to various insects and have high injectable insecticide activity at 24 h.