6: Running after the truth: Methods of attraction and deterrence of codling moth larvae

Dr. Pete Landolt had a significant impact on my life both professionally and personally. From 1996 to 1998, I worked as a biological specialist at the USDA ARS laboratory in Wapato Washington studying methods to control and reduce the effects of fruit pest insects. Pete and I spend many hours running marathons together and found the time to coauthor manuscripts together. Here, I discuss three manuscripts that studied the effects of volatiles on codling moth Cydia pomonella larval orientation. We tested attraction and deterrence of neonate codling moth larvae to 27 plant essential oils and volatiles such as alpha-farnesene released by infested apples. Using olfactometer assays, we found that infested apples and the compound alpha-farnesene increased taxis and upwind movement to these volatiles while oils such as lavender, pennyroyal, and cypress were most effective in preventing larvae from moving upwind in the olfactometer. In a barrier assay, the most effective repellents were rue, garlic, patchouli, and tansy oils. These materials, or their active ingredients, can be useful in protecting fruit from attack by codling moth larvae by preventing larvae from orienting to and arriving at fruit. Pete was a prolific scientific writer and made many discovers that pushed the field of insect chemical ecology and we are grateful for his openness, friendship, curiosity, and leadership.