Fumigant and contact toxicity of 22 wooden essential oils and their major components against Drosophila suzukii (Diptera: Drosophilidae)

Abstract Fumigant and contact toxicities of 22 plant essential oils (EOs) from 14 families and their constituents against the adult spotted wing drosophila (SWD), Drosophila suzukii were examined. Analyses by GC, GC-MS, and NMR led to the identification of 2, 16, 13, 4, 6, 9, and 10 compounds from Gaultheria fragrantissima , Croton anistatum , Illicium verum , Liquidamabar orientalis , Cinnamomum cassia , Rosa damasena , and Santalum album , respectively. In fumigant toxicity test, G. fragrantissima , C. anistatum , and I. verum exhibited 100, 93.8, and 95.8, and 100, 70.0, and 80.0% mortalities against the adult male and female SWD at 4.41 mg/L air, respectively. LC 50 values (mg/L air) of G. fragrantissima , C. anistatum , and I. verum were 3.46, 3.67, and 3.16 against male, and 3.48, 4.31, and 4.01 against female SWD. LC 50 values (mg/L air) of methyl salicylate and trans -anethole were 2.17 and 1.75 against male and 2.65 and 3.00 against female SWD, respectively. In contact toxicity tests, L. orientalis , C. cassia , R. damasena , and S. album showed insecticidal activity with LD 50 values (μg/fly) of 2.64, 1.84, 3.40 and 2.18 against male SWD and of 3.74, 2.24, 8.91 and 5.61 against female SWD, respectively. 2-Phehy-1-ethanol, 3-phenyl-1-propanol, trans -cinnamaldehyde, trans -cinnamyl alcohol, and α-santalol also exhibited insecticidal activity with LD 50 values of 9.79, 5.52, 2.39, 3.02 and 2.37 against male SWD and of 11.77, 7.04, 2.94, 3.32, and 3.99 against female SWD, respectively. trans -Cinnamaldehyde exhibited the highest AChE inhibition but its inhibition is likely due to a non-specific chemical inhibition. Our results indicate that wooden EOs and their components can be used as fumigants or spray-type control agents against SWD