|Shapiro Ilan, David|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/7/2001
Publication Date: 12/1/2002
Citation: LEWIS, E.E., SHAPIRO ILAN, D.I., MCCOY, D.W. DEVELOPMENT RATES IN ENTOMOPATHOGENIC NEMATODES: INFECTED HOSTS VERSUS AQUEOUS SUSPENSION. JOURNAL OF NEMATOLOGY. 2002. Journal of Nematology. v.34. p.340-342. Interpretive Summary: Entomopathogenic nematodes are tiny round worms that kill many important insect pests, but do not harm humans, other animals, or the environment. It is important to understand the factors that affect the biology of these beneficial nematodes so that we can apply them more effectively. In this study, we found that the presence of a nematode-infected insect cadaver increases the development rate of certain juvenile nematodes in subsequent infections. It is likely that a specific chemical is responsible for the observed increase in development-rate. Identification of this chemical may lead to more efficient production methods for these nematodes, and better control of insect pests.
Technical Abstract: The effects of rearing conditions have been shown to affect several aspects of entomopathogenic nematode biology, including dispersal behavior and infectivity. The present study explores the differences in developmental-rate of Heterorhabditis bacteriophora and Steinernema carpocapsae when infective juveniles (IJs) were collected using a White trap, which is standard laboratory practice, versus when they are allowed to emerge naturally into sand. We exposed Galleria mellonella to IJ entomopathogenic nematodes that were treated in one of three ways: collected in a White trap, allowed to emerge directly into sand, or collected in a White trap and treated with a cadaver homogenate. Steinernema carpocapsae IJs developed into adults at a faster rate when they were allowed to emerge directly into sand than when they were collected by other means. The difference in development was shown not to be attributable to differential infection rates. This difference was not found in H. bacteriophora