Control efficacy of controlled atmosphere and temperature treatment system against the hawthorn spider mite, Tetranychus viennensis.
The hawthorn spider mite, Tetranychus viennensis, is a pest of apples and a quarantine pest from some countries that import apples from Korea. A controlled atmosphere and temperature treatment system (CATTS) was developed as an alternative disinfestation method to methyl bromide fumigation treatment, and has been applied to control various insects and other arthropod pests on fruits. We applied CATTS to disinfect T. viennensis under conditions that were previously developed to control the peach fruit moth, Carposina sasakii. First, T. viennensis was sampled from Japanese apricot, Prunus mume, and identified by its morphological characters. In addition, both cytochrome oxidase I (COI) and internal transcribed spacer (ITS) sequences supported the morphological identification. Second, the heat-tolerant developmental stage was determined in T. viennensis. When a 46°C heat treatment was applied to egg, nymph, and adult stages of T. viennensis, adults were the most tolerant stage. Third, when heat temperature was used along with 1% O2 and 15% CO2, the mites showed a significant increase in susceptibility to the heat treatment. Finally, CATTS at 46°C with 15% CO2 and 1% O2 for 30 min resulted in 100% mortality of all T. viennensis development stages. These results indicated that CATTS is applicable to disinfest T. viennensis in post-harvest apples.