Akademik Veri Yönetim Sistemi
International Balkan Agriculture Congress 2025, Balıkesir, Türkiye, 15 - 18 Ekim 2025, cilt.1, sa.1, ss.49-50, (Özet Bildiri)
In biological control, mass production of host insects is essential for the production of beneficial insects, as they are used as food and breeding grounds. To produce sufficient numbers of beneficial insects, it's crucial to have a high host insect population not only during production but also during application periods to boost beneficial insect populations. To achieve this, lowtemperature storage studies are of great importance for both backup and synchronization with the beneficial insects during periods when the host population is high. This study aimed to determine the survival rates of first-instar larvae of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) and Plodia interpunctella Voegele (Lepidoptera: Pyralidae), which are mass-rearing hosts for many beneficial insects, at two different temperatures and six different storage durations. For this purpose, larvae were stored at 5°C and 8°C for 2, 4, 6, 8, 10, and 12 days in refrigerators. The experiments were set up with 10 replicates for each storage duration. Each replicate consisted of 10 first-instar larvae, 0-6 hours old, in an Eppendorf tube. At the end of the storage periods, the Eppendorf tubes were removed from the refrigerators and placed in a climate chamber (25 ± 1°C temperature, 60-65% relative humidity). After a 30-minute acclimatization period, the number of live and dead larvae was determined under a stereobinocular microscope. Survival rates were calculated from these data, and ANOVA was used to compare the means to determine the effect of different storage temperatures and durations. In cases where significant differences were found, Tukey's multiple comparison test was used to identify which means were statistically different from each other. The study's results showed no significant difference in the survival rates of first-instar E. kuehniella and P. interpunctella larvae at 5°C across all storage durations. However, at 8°C, the survival rates of E. kuehniella larvae were statistically higher than those of P. interpunctella larvae across all storage durations. For Ephestia kuehniella stored at 5°C, no significant difference was observed between 2-day and 4-day storage, but the survival rate progressively decreased with longer storage periods. For the same species at 8°C, the 2-day storage duration resulted in a significantly higher survival rate compared to all other storage periods. When comparing the storage temperatures for the same storage durations for E. kuehniella, the survival rate of larvae stored at 8°C was significantly higher than at 5°C for all storage durations. Regarding the survival rates of P. interpunctella larvae at 5°C, the 2-day and 4-day storage durations resulted in significantly higher survival rates compared to other durations. The 6-day storage duration also showed a statistically significant higher survival rate compared to the 8, 10, and 12-day storage periods. For the same species at 8°C, the 2-day storage duration had a significantly higher survival rate than other durations, and the 4-day storage duration also showed a higher survival rate than the other days. When examining the differences between temperatures for P. interpunctella at different storage durations, no significant difference was found between temperatures for the 2, 6, 8, and 10-day storage periods. However, at 4 days of storage, the survival rate at 5°C was determined to be higher than at 8°C. A statistical comparison could not be made for the 12-day storage duration as all larvae died at both temperatures. In conclusion, both storage temperature and duration have a significant impact on the survival rates of firstinstar E. kuehniella and P. interpunctella larvae. In both species, the survival rates of larvae significantly decreased as the storage duration increased, with nearly all larvae dying after 12 days of storage. The only exception was E. kuehniella at 8°C, where some larvae remained alive 50 on the 12th day. This suggests that 8°C is a more suitable temperature for longer-term storage of E. kuehniella. The complete mortality of P. interpunctella larvae even at 8°C indicates that this species is more sensitive to the adverse effects of low temperatures than E. kuehniella. The data obtained from this study are considered preliminary and valuable for future research on the storage of host insects in other life stages.
Keywords: Biological control, cold storage, host, mass production, synchronization.