Location: Fruit and Tree Nut ResearchTitle: Aggregative group behavior in insect parasitic nematode disperal Author
|Shapiro Ilan, David|
Submitted to: International Journal for Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/4/2013
Publication Date: 1/10/2014
Citation: Shapiro Ilan, D.I., Schliekelman, P., Lewis, E.E. 2014. Aggregative group behavior in insect parasitic nematode disperal. International Journal for Parasitology. 44: 49-54. Interpretive Summary: Entomopathogenic (insect-killing) nematodes are small round worms that are used as natural bio-insecticides. These nematodes only kill insects and are not harmful to human or the environment. In order to use these beneficial nematode more effectively in biological pest suppression we need to understand their behavior. The study of movement behavior in nematodes is critical to understanding how nematodes find insects pests to attack in the soil. In this study movement behavior of six different entomopathogenic nematodes was explored. We discovered that nematode movement was not random but rather the nematodes moved together in a group. One might liken their movement to group behavior in other animals such as a herd or a pack of wolves. These findings contribute to the elucidation of nematode ecology, and may be leveraged to enhance biocontrol potential.
Technical Abstract: Movement behavior is critical to determination of spatial ecology and success of foraging in predators and parasites. In this study movement behavior of entomopathogenic nematodes was explored. Movement patterns in sand were investigated when nematodes were applied to a specific locus or when the nematodes emerged naturally from infected insect hosts; six nematode species were tested (Heterorhabditis bacteriophora, H. indica, Steinernema carpocapsae, S. feltiae, S. glaseri, and S. riobrave). Nematodes were applied in aqueous suspension via filter paper discs or in infected insects host cadavers (to mimic emergence in nature). We discovered that nematode dispersal followed an aggregate pattern rather than a random or uniform distribution; the only exception was S. glaseri when emerging directly from infected hosts. These findings have implications for parasitic nematode spatial distribution and suggest that group behavior is involved in nematode foraging.