The effect of microwave radiation with cold storage on the egg mortality of Indian meal moth (Plodia interpunctella Hub.)

The effect of microwave radiation with cold storage on Indian meal moth eggs was investigated. The eggs were exposed to (2450 MHZ) at power levels of 100, 300 and 500W with 2, 4, 6, 8 and 10 min duration. After treatment, the samples were kept under cold storage conditions (4±1°C) for 24 and 48h. Upon termination of cold storage period, the samples were placed under rearing conditions (27 ± 1°C, 65 ± 5% r. h.). In overall, mortality rate had direct relation with microwave radiation power and exposure time. Moreover after 24 and 48 h cold storage 100% mortality was achieved. The results showed that the maximum mortality (90.0 and 85.5%) was achieved for 1 and 2 day old eggs after 48 h cold storage duration respectively. In case of 1 and 2 day old eggs, 24 h cold storage treatment was sufficient to achieve the highest mortality and 1 and 2 day old eggs were more tolerant. It can be concluded that due to low rate of embryonic development within the first 2 days of incubation, the mortality rate of younger eggs could be significantly less.