Early colonization events in the mutualistic association between Steinernema carpocapsae nematodes and Xenorhabdus nematophila bacteria

Monitoring of nematodes throughout their reproductive cycle, using an in vitro culturing technique, reveals that the infective juvenile colonization is initiated by the Xenorhabdus nematophila bacteria by competing for colonization sites within the Steinernema carpocapsae nematode intestine. Data indicate that the final population of bacteria in the nematode is monoclonal originating from one or two bacterial clones.