Meeting Abstract
Previous research demonstrated that Steinernema carpocapsae infective juveniles (IJs) exposed to a host cuticle were more attracted towards certain host volatile odors. We wanted to test the specificity of attraction that results from exposure to host cuticle. To do so, S. carpocapsae host recognition behavior was analyzed after stimulating IJs by allowing them to physically interact with Galleria mellonella cuticles. We measured the behavioral response and the percentage of the population participating in chemotaxis behavior to multiple host odors in volatile chemotaxis assays after the IJs were exposed to the host cuticle of G. mellonella or a sham control. We found that exposure to host cuticles resulted in a higher percentage of the population participating in chemotactic behavior. We tested whether exposure to live host cuticle or dead host cuticle resulted in a different response and found that a higher percentage of IJs exposed to a live host cuticle participated in chemotactic behavior than IJs exposed to a dead host cuticle, but that IJs exposed to a dead host demonstrated significantly higher participation than was observed for non-stimulated IJs. To test whether the increase in IJ participation in host-seeking behaviors after exposure to a live host cuticle was specific, we exposed stimulated IJs to a known repulsive odor, a neutral odor, and a known attractant. We found that stimulation of IJs through physical contact with a host cuticle induces a specific enhancement of host-seeking behavior to host-specific odors rather than a general increased chemotactic response to all volatile stimuli. Future work will be aimed at elucidating the mechanism through which contact with live host cuticle stimulates increased behavioral response.
