Piperitone (p-menth-1-en-3-one): A new repellent for tea shot hole borer (Coleoptera: Curculionidae) in Florida avocado groves

Authors: Kendra, Paul; Montgomery, Wayne; Tabanca, Nurhayat; Schnell, Elena; VAZQUEZ, AIME - Oak Ridge Institute For Science And Education (ORISE); MENOCAL, OCTAVIO - University Of Florida; CARRILLO, DANIEL - University Of Florida; Cloonan, Kevin

Submitted to: Biomolecules EISSN 2218-273X
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2023
Publication Date: 4/6/2023
Citation: Kendra, P.E., Montgomery, W.S., Tabanca, N., Schnell, E.Q., Vazquez, A., Menocal, O., Carrillo, D., Cloonan, K.R. 2023. Piperitone (p-menth-1-en-3-one): A new repellent for tea shot hole borer (Coleoptera: Curculionidae) in Florida avocado groves. Biomolecules. 13(4): 656. https://doi.org/10.3390/biom13040656.
DOI: https://doi.org/10.3390/biom13040656

Interpretive Summary: The tea shot hole borer (TSHB) is a new invasive wood-boring beetle first detected in Florida in 2012. Female beetles carry fungal spores that they transfer to host trees during initial infestation, and these spores develop into fungal gardens which provide food for immature beetles. This fungus also causes a lethal disease in avocado called Fusarium dieback. The avocado industry in Florida is already threatened by another lethal vascular disease, laurel wilt, that is spread by the redbay ambrosia beetle, and growers need new tools to manage TSHB in their groves. Scientists from the USDA-ARS (Miami, FL) and the University of Florida, Tropical Research and Education Center (Homestead, FL) conducted trapping tests to examine the efficacy and field longevity of two candidate TSHB repellents, piperitone and a-farnesene, as compared to verbenone, the standard bark beetle repellent. Laboratory tests were also conducted to quantify the emissions from formulated repellent dispensers and test the sensitivity of TSHB antennae to each candidate repellent. All tests indicated that a-farnesene was ineffective, that piperitone and verbenone achieved 50-70% reduction in TSHB capture in lure-baited traps, and that repellency for both repellents lasted for 10-12 weeks in the field. Piperitone is less expensive than verbenone making it an economical repellent for the TSHB. The use of repellent compounds as part of an integrated pest management program may offer avocado growers a new tool to prevent TSHB infestation in their groves and prevent dieback disease.

Technical Abstract: The tea shot hole borer, Euwallacea perbrevis, recently established in Florida, USA, where it vectors fungal pathogens that cause Fusarium dieback in avocado. Pest monitoring uses a 2-component lure containing quercivorol and a-copaene. Incorporation of a repellent into IPM programs may reduce the incidence of dieback in avocado groves, particularly if combined with lures in a push-pull system. This study evaluated piperitone and a-farnesene as potential repellents for E. perbrevis, comparing their efficacy to that of verbenone. Replicate 12-wk field tests were conducted in commercial avocado groves. Each test compared beetle captures in traps baited with 2-component lures versus captures in traps containing lures plus repellent. To complement field trials, Super-Q collections followed by GC analyses were performed to quantify emissions from repellent dispensers field-aged for 12 weeks. Electroantennography (EAG) was also used to measure beetle olfactory response to each repellent. Results indicated that a-farnesene was in-effective; however, piperitone and verbenone were comparable in repellency, achieving 50-70% reduction in captures, with longevity of 10-12 weeks. EAG responses to piperitone and verbenone were equivalent, and significantly greater than response to a-farnesene. Since piperitone is less expensive than verbenone, this study identifies an economical new repellent for IPM of E. perbrevis in Florida.