Isolation and evaluation of bacteria associated with entomopathogenic nematode Heterorhabditis spp. against the spider mite, Tetranychus truncatus Ehara (Acari: Tetranychidae)

Abstract Background Entomopathogenic nematodes (EPNs) belonging to the Heterorhabditis spp. harbour symbiotically associated bacteria which are toxic a wide range of insect pests. Isolation, purification, characterization and mass multiplication such will be promising strategy in management This study was carried out isolate EPN from different locations, purify bacterial colonies, characterize through morphological molecular strategies test efficacy control polyphagous Tetranychus truncatus Ehara mites. Results EPNs were isolated soil samples at 11 localities Kerala State, India, used infect Galleria mellonella L. larvae. Bacteria with haemolymph infected larvae isolated, on NBTA medium have produced circular irregular, entire, opaque smooth colonies. Sequence 16S rRNA revealed nine isolates namely: one symbiotic bacterium Photorhabdus luminescens , two Pseudomonas aeruginosa five Ochrobactrum sp. Stenotrophomonas maltophilia. Phylogenetic analysis using sequences has further confirmed identity. Evaluation cell suspension (CS) cell-free supernatant (CFS) P. for their adulticidal ovicidal efficiencies T. had identified significant effects by luminescens, followed aeruginosa. After 96 h treatment, 10 8 cells/ml resulted significantly higher mortality rate adult mites (64.00 60.67%, respectively, CFS CS), compared that (38.67 33.33%). Conclusions this showed is biocontrol agent .