|Shapiro ilan, David|
Submitted to: Journal of Nematology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/11/2005
Publication Date: 8/15/2006
Citation: Shapiro Ilan, D.I., Stuart, R.J., Mccoy, C.W. 2006. A comparison of entomopathogenic nematode longevity in soil under laboratory conditions. Journal of Nematology. 38:119-129. Interpretive Summary: Entomopathogenic nematodes are environmentally friendly natural insecticides. These small round worms kill insect pests but don't harm people or other animals. The nematode's success in killing insects relies heavily on how long they survive in the soil. We tested a wide variety of different nematode species and strains for their ability to survive in soil (11 species and 29 strains). A species is a taxonomic group of organisms that can mate with each other. A strain is a more narrow division within a species. We found that the nematode species called Steinernema diaprepesi and S. carpocapsae had the greatest longevity, whereas the species Heterorhabditis indica, H. mexicana and H. marelatus had the lowest survivability. A number of other species had intermediate survival capabilities.
Technical Abstract: In the laboratory, we compared the longevity of 11 entomopathogenic nematode species and 29 strains in soil. Substantial within species (strain) variation in longevity was observed in Steinernema carpocapsae with the Sal strain exhibiting the greatest survival. In contrast, little inter-species variation was observed in S. riobrave. Overall, we estimated S. carpocapsae (Sal) strain and S. diaprepesi to have the highest survival capability. A second level of longevity was observed in Heterorhabditis bacteriophora (Lewiston), H. megidis, S. feltiae, and S. riobrave. Lower levels of survivability were observed in other H. bateriophora strains (Hb, HP88, and Oswego), as well as S. glaseri and S. rarum. Relative to S. glaseri and S. rarum a lower tier of longevity was observed in H. indica and H. marelatus, and H. mexicana, respectively. Our experiments concerning nematode longevity and persistence should be helpful when considering which nematode strain or species to use in field applications for pest control.