The utilization of methyl bromide (MB) for quarantine purposes has been hampered by its designation as an ozone-depleting substance under the Montreal Protocol. The International Plant Protection Convention's (IPPC) call for alternatives to MB and a reduction in its usage. There is an urgent need to explore and implement substitutes. Despite some substitute agents like EDN being developed for wood, EDN has been limited due to various factors such as occupational risks. This study focuses on evaluating the efficacy of Sulfuryl Fluoride (SF) as a viable alternative fumigant against Reticulitermes speratus, one of major wood destroying pests. Experimental trials conducted at ambient temperature (23°C) revealed promising results, with SF demonstrating LCT50 and LCT99 values of 30.87 mg·h/L and 42.53 mg·h/L, respectively. Under low-temperature conditions (5°C), SF remained effective but with slightly higher LCT50 and LCT99 values of 151.62 mg·h/L and 401.90 mg·h/L, respectively. The penetration test, conducted using R. speratus-infested pine wood cubes, further highlighted SF's efficacy, with LCT50 and LCT99 values of 31.59 mg·h/L and 53.34mg·h/L at 23°C, indicating powerful penetration capabilities. When tested at a loading ratio of 90% (v/v) at 5.0mg/L for 24 hours in a 500L chamber as a middle-scale trial, SF achieved a 100% mortality, showing its potential as a suitable replacement for MB. These findings suggest that SF could open new markets as an MB substitute and enhance safety at quarantine sites when applied to imported and exported timber.
Research on alternative fumigants to replace methyl bromide (MB), a harmful ozone-depleting substance and highly toxic pesticide, began in 2007. Initial tests focused on using ethyl formate for fruits and EDN for wood. Subsequently, alternative techniques were developed for a total of 94 plant types using ethyl formate, EDN, and phosphine, demonstrating Korea's superior performance compared to other countries, especially in practical applications. However, when it comes to wood products, the primary users of methyl bromide, EDN is scarcely used due to concerns about worker safety. An emerging alternative to MB is sulfuryl fluoride (SF), widely employed in North America to control wood-damaging pests like termites. SF's advantages include a lower boiling point and higher vapor pressure, making it effective against wood pests. Yet, certain bark beetle eggs require higher doses and longer treatment periods, resulting in established international standards (e.g., 120g/m3 for 48 hours at 20℃), posing challenges for field applications. Recently, the APQA initiated basic research to apply SF to wood. They are assessing SF's effectiveness against various wood-destroying pests, including termites, bark beetles, and long horn beetles, while also evaluating the feasibility of mixed treatments to reduce dosage. Once SF fumigation standards are established, it is expected to significantly reduce methyl bromide use in commonly used wood types, contributing to ozone layer protection and enhancing fumigation work safety.
Methyl bromide (MB) has been still routinely used in quarantine fumigation on imported citrus, although there had been issuing chronic inhalation toxicity to fumigators and related workers as well as phytotoxic damages after fumigation. Ethyl formate (EF), is the only option to replace MB in terms of its safety for consumers (food additive and naturally occurred) and worker with higher threshold level limit (TLV = 100 ppm). Its application technology also provide cost effectiveness, good commercial practice in terms of application time (< 10 min) for 40 ft container. The replacement of MB with EF is recommended not to fumigate with hazardous and phasing-out MB on imported oranges.
Whitefly (Hemiptera: Aleyrodidae) pests, including the tobacco whitefly, Bemisia tabaci, and the greenhouse whitefly, Trialeurodes vaporariorum, are economically important in agriculture. With the annual growth of the domestic fresh fruit export market, various quarantine treatment methods are being used to export strawberries of better quality. The objective of the present study was to evaluate the effects of gamma rays on the development and reproductive sterility of B. tabaci and T. vaporariorum. In both species, the eggs were completely inhibited from hatching at 50 Gy, and the emergence of 3rd instar nymphs was completely suppressed at 150 Gy. Some adult B. tabaci and T. vaporariorum spawning occurred at 100 Gy and 70 Gy, respectively; however, at these irradiation levels, F1 hatchability was completely inhibited. Dosimetry results showed that the penetrating power of gamma ray in the strawberry-filled box was the lowest at the mid-box position. Therefore, B. tabaci and T. vaporariorum were placed in the middle of the strawberry-filled box and irradiated. A gamma-ray irradiation of 100 Gy suppressed the development and reproduction of eggs and adults in both B. tabaci and T. vaporariorum. However, the development of 3rd instar nymphs was inhibited at 300 Gy for B. tabaci and 200 Gy for T. vaporariorum. Our data suggest that at least 300 Gy should be used for the control of these two types of whitefly for strawberry export.
The spotted wing drosophila (SWD), Drosophila suzukii, is classified exotic quarantine pest in Australia and EU, soSWD-free must be supported by evidence of surveys and phytosanitary measures in exported host agricultural commoditiesin Korea. From a quarantine control point of view, SWD is importantly considered as model insect pest for exotic fruitflies (Bactrocera dorsalis) in Korea as well because of similarity in ecological cycles. In evaluations of ethyl formate(EF) only and combined cold treatment to kill eggs and larvae of SWD, the combined EF fumigation applied at LCt50%(50% killed lethal concentration X time) and cold treatement (5℃) for > 5 days showed the promise to new conceptfor eradicating quarantine pest and these could be helpful to pre-develop exotic fruit fly management in Korea.
Rapid growth in trade of agricultural products has increased the risk of introduction of exotic pests into new area. In order to fulfill quarantine obligations, several treatments are in practice: fumigation with methyl bromide (MB), application of extreme temperatures, controlled atmospheres, and combinations of them. Although MB was most effective and widely applied for quarantine treatment, its use was banned by the Montreal Protocol. Ionizing irradiation phytosanitary treatments – gamma radiation, electron beam, and X-ray are being used as an alternative to MB currently. For applying ionizing irradiation as a quarantine treatment, there is a research protocol which should be followed, International Standards for Phytosanitary Measure 18 [ISPM #18] and Phytosanitary Treatment Regulation of Korea (Notice 2014-35).
We have evaluated the effect of gamma radiation, electron beam, and X-ray on H. armigera as quarantine treatments. In this presentation, ISPM #18 and Notice 2014-35 will be talked with the example of H. armigera.
Postharvest insect pest control is highly demanding in agricultural industry including domestic consumer markets and exporting products for a quarantine purpose. Especially, the organic or environmentally friendly agricultural products do not fit to the traditional chemical postharvest treatments using methyl bromide (MeBr) or phosphine (PH3). As an alternative, a physical treatment called CATTS (controlled atmosphere and temperature treatment) has been developed to control various insect and mite pests on ornamental products. The oriental fruit moth, Grapholita molesta, infects the apple or pear fruits and is limited in importing and exporting the infected products. To apply CATTS on this insect pests, the most heat-tolerant stage was determined. Among the immature stages locating on the fruits, the fifth instar larvae were the most tolerant to 44℃ for 20 min. A ramping step of CATTS is to increase chamber temperature from 25℃ to 46℃ under 15% CO2 and less than 1% O2. The ramping rate was positively correlated with the CATTS efficiency. After the ramping step, the duration of CATTS was positively correlated with CATTS efficiency. However, fruit damage by CATTS was negatively correlated with the ramping rate was positively correlated with the CATTS duration. in addition, the CATTS efficiency was highly dependent on the fruit internal temperature at 44℃. From all these parameters, we developed a standard protocol yielding 100% control efficiency of CATTS.