ABSTRACT
With the widespread distribution of entomogenous nematodes for biological control, there is always concern of possible effects on nontarget organisms such as plants, other invertebrates, and vertebrates, including man. The species of fungi involved are considered harmful in many cases, and therefore their possible reduction by feeding nematodes would not be significant. Since many stream invertebrates are important entities in the food chain for fish and other vertebrates, some tests have been conducted with the mermithid Romanomermis culicivorax to determine if nontarget invertebrates are susceptible. Another nematode that has been mass produced, Neoaplectana carpocapsae, has also been tested against vertebrates. The wide range of entomogenous nematodes, only members of the family Mermithidae have occasionally been reported as accidental parasites of man. None of the invertebrates tested were able to support the complete development of R. culicivorax, and on the basis of these tests, one can assume that the widespread distribution of this mermithid will not affect organisms other than mosquitoes.
