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Abstract
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Soil-dwelling nematodes from Steinernematidae family are obligate parasites of insects and usually referred
to as entomopathogenic nematodes (EPNs). These nematodes are symbiotically associated with entomopathogenic
bacteria Xenorhabdus spp. The bacterial symbionts are carried monoxenically in a special vesicle in the infective
juveniles (IJs). In the present study we report the isolation of two species of non-symbiotic bacteria from infected
insect cadavers by the EPN, Steinernema feltiae. Galleria mellonella L. larvae were exposed to surface sterilized
infective juveniles of S. feltiae and transferred to sterile Petri dishes for a further 24 hours. Hemolymph was
collected and streaked onto both MacConkey and NBTA agar. Bacteria were identified using biochemical and
phylogenetic analysis. 16S-rRNA gene sequence based maximum parsimony, maximum likelihood and neighbour
joining phylogenetic analyses were conducted. Two non-symbiotic species including Citrobacter freundii and
Staphylococcus succinus were identified and reported to be associated with S. feltiae. Our results provide further
evidence for the existence of non-symbiotic bacteria associated with EPNs infection
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