ARS | Publication request: VIRULENCE OF ENTOMOPATHOGENIC NEMATODES TO PECAN WEEVIL LARVAE, CURCULIO CARYAE (COLEOPTERA: CURCULIONIDAE), IN THE LABORATORY

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 2, 2000
Publication Date: January 1, 2001
Citation: Shapiro Ilan, D.I. 2001. Virulence of entomopathogenic nematodes to pecan weevil larvae, Curculio caryae (Coleoptera: Curculionidae), in the laboratory. Journal of Economic Entomology. v.94. p.7-13.

Interpretive Summary: The pecan weevil is a devastating insect pest of pecans in the Southeastern United States. Insect-killing nematodes are natural pesticides that may represent an environmentally-friendly solution to the pecan weevil problem. In this study we compared 15 different kinds of nematodes to see which might be the best candidate for killing pecan weevils. All the nematodes tested were able to kill pecan weevils, but no nematode stood out above the rest. Additionally, data indicated that, as pecan weevils age, they may become resistant to nematode infection. This study was a good first step toward developing a non-chemical method of controlling pecan weevils.

Technical Abstract: The pecan weevil, Curculio caryae (Horn) is a key pest of pecans in the Southeast. Prior to this research only three species of entomopathogenic nematodes had been tested against pecan weevil larvae. In this study, we tested the virulence of 9 species and 15 strains of nematodes towards pecan weevil larvae. Steinernatids did not produce greater mortality than the control whereas Heterorhabditids did. Heterorhabditis megidis (UK211) but not H. indica (original) displayed a positive linear relationship between nematode concentration and larval mortality. Results suggested that, as pecan weevil larvae age, they may have become more resistant to infection with entomopathogenic nematodes.