As global warming and consumer’s preference for tropical/subtropical fruits increase, the number of orchards cultivating tropical/subtropical fruits in Korea is increasing. Accordingly, concerns about the introduction of exotic invasive pests that host tropical fruits. In this study, efficacy of ethyl formate(EF), as alternative to methyl bromide(MB), was evaluated. Commercial trial of EF was conducted in mango post-harvest storage conditions for controlling Scirtothrips dorsalis. Application of 10 g/m3 of EF for 4 hours at 10 ℃ showed proven efficacy on S. dorsalis without any phytotoxic damage on mango fruits in that condition.
Ethyl formate (EF) is a potent fumigant replacing methyl bromide. The use of EF is limited to a quarantine process. Appling EF to agricultural field as a safe insecticide in greenhouse give us valuable benefits including less residual concern. In this regard, residual pattern after EF fumigation in greenhouse should be undertaken. In the previous study, we have established agricultural control concentration of EF to control pests in a greenhouse. EF was fumigated at 5 g m-3 level for 2 h. The concentration of EF inside a greenhouse was analyzed to be 4.1-4.3 g m-3 at 30 min after fumigation. To prepare an analytical method for residues in cucumber crops and soil in the greenhouse, the limit of detection (LOD) of the method was 100 ng g-1 and the limit of quantitation (LOQ) of this method was 300 ng g-1. R2 values of calibration curves for crops and soil were 0.991-0.997. In samples collected immediately after ventilation, EF concentration was determined to be below LOQ level. In addition, EF level was below LOQ in samples collected at 3 h after ventilation except that leaf samples of melon during the flowering period showed a level of 1,068.9 ng g-1. Taken together, these results indicate that EF used in quarantine can be applied to agricultural fields without residual issue as an effective fumigant for insect pest control.
에틸포메이트는 살충 효과가 빠르고 환경에 무해하며 특히 인축독성이 낮아 검역용 훈증제로 등록되어 있다. 이러한 에틸포메이트를 이용하여 훈증 챔버 (0.275 m3) 내에서 4종의 농업 해충 (오이총채벌레, 담배가루이, 복숭아혹진딧물, 점박이응애)과 4종의 작물 (참외, 오이, 토마토, 고추) 유묘기를 대상으로 12시간 훈증 처리하여 약효와 약해를 평가하였다. 에틸포메이트 1.5 g/m3의 약량으로 12시간 훈증 했을 때 담배가루이와 복숭아혹진딧물은 93.3% 이상의 높은 살충력를 나타내었으나, 점박이응애는 2.0 g/m3 약량에서도 20% 미만의 낮은 살충력을 나타내었다. 그리고 에틸포메이트의 CT값(농도ⅹ시간)이 훈증 처리 온도 20 ± 1.5℃에서 8.9 g・h/m3 이상일 때 점박이응애를 제외한 나머지 3종의 해충에 대해서 90% 이상의 살충 효과를 얻을 수 있었다. 에틸포메이트 1.5 g/m3의 약량으로 상기 4작물을 12시간 훈증했을 때 약해 증상은 나타나지 않았다. 따라서 에틸포메이트 훈증기술은 시설 내 해충방제를 위한 새로운 방식이 될 수 있으며 관행적인 살충제의 사용을 줄일 수 있을 것으로 생각된다. 그러나 해충의 충태별, 작물의 생육 시기별 에틸포메이트 약효 및 약해에 대한 많은 연구가 이루어져야 할 것으로 생각된다.