Nematodes are microscopic roundworms that live in soil, oceans, and lakes. Scientists estimate that there could be a million species of nematodes and that many of them are parasites. Sometimes farmers use parasitic nematodes as a natural enemy to kill some pests. This is one type of biological pest control.
We studied a particular parasitic nematode called Steinernema scapterisci. It infects insects and has been used as biological pest control in the United States.
Some parasites are generalists and can infect a wide variety of hosts while others are specialists and only infect certain hosts. We wanted to determine if S. scapterisci really is a specialist parasite and why it is a picky eater (showing a preference for one insect over another). To do this we studied how these nematodes behave when given different insects as food.