|Shapiro Ilan, David|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2004
Publication Date: 12/1/2004
Citation: Perez, E.E., Lewis, E.E., Shapiro Ilan, D.I. 2004. Effect of application method on fitness of entomopathogenic nematodes emerging at different times. Journal of Nematology. 36:534-539. Interpretive Summary: Insect-killing nematodes are small round worms that kill insect pests but don't harm people or the environment. Generally, these nematodes are applied in water by spraying them onto the target area. It may also be possible to apply the nematodes while they are inside the insect cadavers that they have killed. In this study, the two application methods were compared: application in dead insects vs. the normal method of applying nematodes in water. Nematodes applied in dead insect cadavers tended to survive longer in soil and kill insects better than nematodes applied in water. This study shows that application of nematodes in infected insect cadavers can be superior to the usual method of application.
Technical Abstract: The entomopathogenic nematode species Steinernema feltiae and Heterorhabditis bacteriophora were used to compare survival and infectivity of infective juveniles (IJ) collected into aqueous suspension (treatment A) vs. IJ allowed to emerge from hosts directly into sand (treatment C). For S. feltiae IJ percentage survival and infectivity decreased with time and was greater for IJ from treatment C than for IJ from treatment A. For H. bacteriophora IJ percentage survival decreased and percentage infectivity increased with time. While percent survival was higher for treatment C compared to treatment A, percent infectivity was not different between treatments. These data provide further evidence that nematodes emerging directly from infected hosts into the soil may be superior in biological control than nematodes applied in aqueous suspension