Sweet persimmons are a valuable export commodity. However, the presence of live insects such as Asiacornococcus kaki limits their access to many export markets. Methyl bromide, traditionally used for pest control, is damaging to human health and the environment. Ethyl formate (EF) is a viable alternative; however, its effectiveness against A. kaki on sweet persimmon fruit is unknown. We evaluated the effectiveness of EF fumigation in controlling A. kaki present under the calyx of persimmon fruit. The hatching rate of eggs and the survival rates of nymphs and adults of A. kaki at low temperatures, its LCt₅₀ and LCt₉₉ after EF exposure, and phytotoxic damage caused by EF were evaluated in laboratory-scale and commercial-scale tests. The dose–response tests showed that the EF LCt₉₉ at 5 °C was 9.69, 42.13, and 126.13 g h m⁻³ for adults, nymphs, and eggs, respectively. Commercial-scale tests demonstrated EF efficacy against all A. kaki stages without causing phytotoxic effects on persimmons, though the eggs of A. kaki were not completely controlled in linear low-density polyethylene (LLDPE)-packaged fruit. This study demonstrated that EF is a potential fumigant for quarantine pretreatment, especially before persimmon fruit is packed with LLDPE film, to control A. kaki infesting sweet persimmon fruit.

Pineapple mealybug, Dysmicoccus brevipes (Hemiptera: Pseudococcidae), is a significant pest in pineapple production and a key trade barrier. We explored the potential use of ethyl formate (EF) as a methyl bromide alternative for the postharvest fumigation of D. brevipes in imported pineapples. When treated at 8 °C for 4 h, EF fumigation was effective against D. brevipes with LCt_99, the lethal concentration × time product of EF necessary to achieve 99% mortality of D. brevipes nymphs and adults at 64.2 and 134.8 g h/m³, respectively. Sorption trials conducted with 70 g/m³ EF for 4 h at 8 °C using 7.5, 15 and 30% pineapple loading ratios (w/v) indicated that loading ratio lower than 30% is necessary to achieve the LCt₉₉ values required to control D. brevipes. In a scaled up trial using 1 m³ chamber, EF fumigation with 70 g/m³ for 4 h at 8 °C with 20% pineapple loading ratio (w/v) resulted in a complete control of D. brevipes treated. There were no significant differences in hue values, sugar contents, firmness, and weight loss between EF-treated and untreated pineapples. Our results suggest that EF is a promising alternative to methyl bromide fumigation for the postharvest phytosanitary disinfection of D. brevipes in pineapples.

Invasive snails and flies are major pests of imported orchids, controlled by methyl bromide (MB) fumigation in Korea. We compared the efficacy and phytotoxicity of ethyl formate (EF) and MB on four species of imported orchids using juvenile stages of Achatina fulica and third and fourth instars of Lycoriella mali. EF was as effective as MB. The LCt₉₉ values of EF were 68.1 and 73.1 g h/m³ at 15 °C; and those of MB were 95.9 and 78.4 g h/m³ at 15 °C for A. fulica and L. mali, respectively. In the scale-up trials, EF treatment at 35 g/m³ for 4 h at 15 °C resulted in complete control of both pests. MB treatment based on the current treatment guidelines for imported orchids (48 g/m³, 2 h, at >15 °C) resulted in complete control of L. mali but not of A. fulica. Chlorophyll content and hue values of treated orchids were not affected by EF treatment but significantly changed by MB (p-value < 0.05). All four treated species of orchids died within 30 d of MB treatment, while only one species died from EF treatment. Our results suggest that EF is a potential alternative to MB in phytosanitary treatment of imported orchids.

In East Asia, especially in South Korea, Perilla frutescens L. is widely cultivated for food and industrial uses. Root-lesion nematodes, particularly Pratylenchus penetrans Cobb, are significant pests in Korean perilla fields, leading to chlorosis, root necrosis, and decreased yields. This study examined the effectiveness of hot-water treatment for controlling P. penetrans in P. frutescens under large-scale conditions at two different temperatures and durations. Additionally, because ornamental plants are often a main route for the international spread of quarantine plant-parasitic nematodes, two commonly traded ornamental species (Syngonium podophyllum L. and Schefflera arboricola L.) were examined alongside P. frutescens to assess how hot water treatment affected their health by measuring weight, chlorophyll content, and root length. Results indicated that the relative reduction in P. penetrans recovery was 99.66% at 48 °C for 20 min and 99.98% at 50 °C for 3 min. While some thermal damage was observed in P. frutescens following both treatments, exposing the plants to 50 °C for 3 min did not significantly affect the quality of S. podophyllum and S. arboricola. These results highlight that hot water treatment effectively controls plant-parasitic nematodes and maintains ornamental plant quality, which could aid in developing quarantine protocols for traded planting materials.