Though quarantine use of methyl bromide(MB) is currently permitted in Korea, there has been phasing out and considering ban in many countries due to their ozone depletion properties. VapormateTM, a new gas formulation of ethyl formate(EF) with carbon dioxide, and VivakilTM, a new gas formulation of phosphine(PH3) with carbon dioxide, are MB alternative fumigants to methyl bromide(MB). For applying on import commodities, the efficacy of EF and PH3 was evaluated for 2hr fumigation on egg, nymph and adult stage of citrus mealybug(CMB), Planococcus citri, at two different temperatures(8, 13℃). The CT(Concentration X Time) product of EF to be expect 99% mortality to egg, nymph and adult stage of CMB were 108.3, 22.4 32.4 gh/m3 at 8℃ and 83.2, 25.1, 29.8 gh/m3 at 13℃, respectively. The CT product of PH3 gas to be expect 99% mortality to nymph and adult stage of CMB were 6.50, 2.55 gh/m3 at 8℃ and 3.72, 3.64 gh/m3 at 13℃, respectively. However, PH3 gas applied at high CT(4.2 gh/m3) for 2hr fumigation was not enough to obtain CT to egg stage of CMB at both temperature conditions. These efficacy data based on CT will be useful to predict the CT model in scale-up fumigation at diverse practical conditions.

For replacement of methyl bromide(MB) in Korea, VapormateTM, a gas formulation of ethyl formate(EF) with carbon dioxide, are firslty introduced in import bananas and VivakilTM, a gas formulation of phosphine(PH3) with carbon dioxide, are ready to commercial use in export cut flowers. Their applications are being extended for other import and export commodities. Ethyl formate have been shown to have effectiveness short exposure time(<4hr) but it has a limited application at low temperature for TSM(Two spotted spider mites) due to some phytotoxic to strawberry. Phosphine gas has demonstrated their efficacy to TSM at low temperature but only meets quarantine requirement when applying longer fumigation time(>24hr) to control CA(cotton aphids). We firstly evaluated two MB alternatives, EF and PH3, have enhansive effect within short exposure time(4hr) at low temperature(5℃) for controlling both TSM and CA without any injury to export strawberries.