BACKGROUND Drosophila suzukii (Matsumura), spotted‐wing drosophila (SWD), is a major invasive pest of soft‐skinned fruits in North America and Europe. Although insecticides are currently the primary method of SWD control, it is imperative to develop alternative management approaches, such as behavioral control through the use of repellents and attractants. This study explores the repellent properties of 2‐pentylfuran as an oviposition deterrent on raspberries. RESULTS 2‐Pentylfuran was found to be aversive to SWD in laboratory multiple‐choice tests. When co‐released from a vial (loaded as neat compound) with a synthetic SWD lure, 2‐pentylfuran reduced SWD attraction to the SWD lure by 98% and the effect appeared 17% stronger compared to 1‐octen‐3‐ol, a known SWD repellent. Releasing 50% 2‐pentylfuran mixed with mineral oil from a vial located near ripe raspberries resulted in 30% reduction in SWD oviposition in the field. In laboratory no‐choice assays, 2‐pentylfuran reduced SWD oviposition on raspberries above 2.5 mg h−1 with greater repellency achieved at higher release rates. A release rate of 10 mg h−1 from a polyethylene sachet reduced egg‐laying on raspberries by 60% in a semifield cage choice experiment. In a field experiment using fruiting raspberry clusters, 14 mg h−1 release rate of 2‐pentylfuran was effective at reducing SWD infestations by 56% compared to untreated plots. CONCLUSION 2‐Pentylfuran acts as a repellent for SWD and can significantly reduce fruit infestations under field conditions and high SWD pressure. Given that 2‐pentylfuran is a registered food additive and generally regarded as safe, 2‐pentylfuran has a potential use in behavioral control strategies against SWD. Published 2020. This article is a U.S. Government work and is in the public domain in the USA

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Ethyl formate (EF) was evaluated as a potential alternative to methyl bromide (MB) for phytosanitary treatment of imported citrus fruit in the Republic of Korea. Planococcus citri (Risso) (Hemiptera: Pseudococcidae), a mealybug with known tolerance against EF and MB, was used as a representative pest to test efficacy of the two fumigants against eggs. In nine commercial-scale refrigerated container (67.5 m3) trials using imported orange, lemon and grapefruit, EF applied at the currently approved dose for citrus (70 g·m-3 at 5°C for 4 h, developed for Aspidiotus excisus Green (Hemiptera: Diaspididae), a species less EF tolerant than P. citri) resulted in 76.9–98.3% mortality of P. citri eggs. The EF treatment did not affect the sugar content or the color of peel and pulp of the treated fruit. When oranges were treated according to the current MB (64 g·m-3 at >5°C for 2 h) or EF treatment guidelines, the concentration of fumigant around the fruit fluctuated between 9.4 and 185.1 ppm for EF and 9.5–203.0 ppm for MB during the 72-h post-fumigation processes (venting [0–2 h], transportation to storage [2–24 h], and storage periods [24–72 h]) with both EF and MB maintained between 10 and 100 ppm during the storage period. Considering the efficacy of EF, its apparent lack of phytotoxicity, and its more manageable threshold limit value for humans (100 ppm EF compared to 1 ppm MB for an 8-h time weighted average exposure), our results suggest that EF may be a promising alternative to MB for the phytosanitary treatment of imported citrus in Korea.