Abstract
Entomopathogenic nematodes (EPN) infect and kill their insect host with the help of symbiotic bacteria. The only known hermaphroditic (androdiecious) EPN, the clade IV Steinernema hermaphroditum , offers opportunities for exploring both parasitic and mutualistic symbiosis, as well as for evolutionary and developmental studies. Experimental and genetic analysis of this animal is now facilitated through the development of forward and reverse genetic tools and improved culturing techniques. Here, we describe a liquid-culture technique adapted for this worm. The method can be a starting point for the development of large-scale cultivation of the worm and provides a method to generate infective juveniles without an insect host and either with or without its native symbiotic bacteria.