|Shapiro Ilan, David|
Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/23/2003
Publication Date: 9/1/2003
Citation: Shapiro Ilan, D.I., Stuart, R., Mccoy, C.W. 2003. Comparison of beneficial traits among strains of the entomopathogenic nematode, steinernema carpocapsae, for control of curculio caryae (coleoptera: curculionidae). Biological Control. 28:129-136. Interpretive Summary: Insect-killing nematodes are small round worms that kill insect pests but don't harm people or the environment. Certain characteristics, such as a high level of virulence (killing power) and the ability to withstand hot or dry conditions, make these nematodes better at killing harmful pests. We compared several characteristics among eight different strains (kinds) of the nematode species Steinernema carpocapsae to see which one(s) might be the best at killing the pecan weevil (an important pest of pecan. Three of the strains (Agriotos, All, and Sal) were the best overall. This study will help us choose which strains to test further, and allow us to improve the strains through genetic methods.
Technical Abstract: Our objective was to compare beneficial traits among strains of Steinernema carpocapsae in order to identify or develop a superior biocontrol candidate for suppression of the pecan weevil, Curculio caryae. Virulence, environmental tolerance to heat and desiccation, and reproductive capacity were compared among eight strains. Fitness (in vitro growth) of the symbiotic bacteria, Xenorhabdus nematophilus, which is associated with this nematode, was also compared among six nematode strains. Significant differences were detected among strains for each trait. Overall, Breton, DD136, and Kapok strains were ranked inferior to other strains. Agriotos, All, and Sal strains were superior when desiccation was a factor. When desiccation was removed as a factor, Italian and Mexican strains also tended to fall into the superior rankings.