Effects of exposure duration in a normal freeze process on the elimination of durian seed borer larvae, Mudaria luteileprosa halloway (Lepidoptera: Noctuidae)
摘要
Mudaria luteileprosa Halloway is a major durian seed borer that restricts international trade. This study evaluated the efficacy of freezing treatments at -15 °C for various durations (0, 5, 10, 15, and 20 min) across four local durian varieties: Mas, Sitokong, Cijambe, and Siketan. The research aimed to determine the most effective exposure time for larval elimination and identify the most resistant larval stage. Results showed that the freezing process followed a second-order polynomial model (R2 = 0.9984–0.9993). Large larvae (> 20 mm) were the most predominant (73–76%) and exhibited the highest cold resistance. Probit analysis estimated the 99% Lethal Time (LT99) to be between 19.23 and 19.26 min for all varieties. Complete mortality (100%) of all larval stages was successfully achieved with a 20-minute exposure at -15 °C. This freezing method is a highly effective post-harvest phytosanitary treatment, ensuring quarantine security and supporting market access for fresh durian exports without compromising fruit quality.