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Meeting Abstract
Entomopathogenic nematodes (EPNs) are insect-parasites that typically kill their hosts within 48 hours of infection and have been used in the biological control of insects. When free-living infective juveniles (IJs) infect a host, they release their bacterial symbiont, and undergo notable morphological changes such as shedding of the cuticle, opening of the mouth, and expansion of their pharyngeal bulb. All of these characteristics can classify an IJ as “activated”, which describes the initial process of transitioning into an active parasite. These EPNs are known to infect and kill different hosts at varying rates. Studying how EPNs activate in different hosts can help us better understand the intricacies of parasitism, host preference, and the initiation of parasitism. Here we investigated EPNs from the genus Steinernema, and quantified their levels of activation based on morphological changes. We found that nematode activation is context dependent, and that IJs that have recently emerged are less likely to activate than IJs that have emerged after a longer period of time.