Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/29/2003
Publication Date: 6/1/2004
Citation: Shapiro Ilan, D.I., Mizell, R.F., Cottrell, T.E., Horton, D.L. 2004. Measuring field efficacy of steinernema feltiae and steinernema riobrave for suppression of plum curculio, conotrachelus nenuphar, larvae. Biological Control. 30:496-503. Interpretive Summary: The plum curculio is a devastating pest of peaches, apples and other stone or pome fruits. Due to environmental and regulatory concerns, alternative non-chemical methods of controlling the plum curculio are needed. Insect-killing nematodes are a potential alternative. These nematodes are small round worms that kill insect pests but don't harm people or the environment. We conducted field tests to determine the ability of two nematodes (called Sf and Sr nematodes) for their ability to control plum curculio larvae. The tests were conducted in peach orchards located in Byron, GA and Quincy, FL. The Sr nematode caused more than 97% control of plum curculio larvae in three out of the four tests and 78% control in the fourth test. The Sf nematode was not effective. This study indicates that the Sr nematode may have great potential to control plum curculio larvae. Further testing will determine how these results might fit into commercial plum curculio management.
Technical Abstract: The plum curculio, Conotrachelus nenuphar, is a major pest of pome and stone fruit. Our objective was to determine the ability of Steinernema feltiae and Steinernema riobrave to control C. nenuphar larvae in the soil. The nematodes were applied in peach orchards at two locations (Byron, GA and Quincy, FL) in 2002 and 2003. The treatments were compared to an untreated control and, in Byron, GA only, application of imidacloprid. In all trials, S. riobrave was the only treatment that caused a significant reduction in weevil emergence. Steinernema riobrave applications resulted in greater than 97% C. nenuphar control (according to Abbott's formula) in two out of three trials, and 77.5% control in the fourth trial (Quincy, FL, 2003). The observed high levels of C. nenuphar control are intriguing. Further studies are required to verify our results in commercial-scale production, and to determine how entomopathogenic nematode applications might fit into an efficacious C. nenuphar management strategy.