Developmental period of Trogoderma variabile can be affected by many factors. The larvae of Trogoderma variabile enter diapause in unfavorable conditions. In this study, a comparison will be made between feeds (wheat flour, mixture of wheat flour and bran, dried pollack) and humidity (15%, 60%) in the same temperature (30℃ ±0.5) for 6 months. In the results, there are differences between feeds. Feeding mixture of wheat flour and bran was the shortest developmental period. Feeding dried pollack took few months to emerge, although we could not observe emergence for wheat flour. Even though humidity makes differences for feeding dried pollack, there were no significant differences for mixture on the different humidity. From that results, we could assume that the strongest affect on the developmental period is feeding material. Additionally, depends on feeding material, the other factors may affect on the developmental period.
Trogoderma variabile B. is one species of well-known stored product insect. This study was conducted to test the perforation ability of larvae of T. variabile on different packaging films which has been widely used in food industry at different thickness. The tested packaging films are polypropylene (PP) 20μm, low density polyethylene (LDPE) 20μm, polyethylene terephthalate (PET) 12μm, PP 30μm and PP 40μm. This investigation was carried out for 7 days. In the same order as the films mentioned above, the perforation rate are 33.33%, 0%, 14.81%, 29.62%, 0%. From these results, the easiest film to perforate among PP, LDPE, PET is PP, and there are significant differences on thickness. Therefore, different type of materials and thickness would be considered to be used for food packaging.