Low temperature to control Plodia interpunctella and Stegobium paniceum

Plodia interpunctella (Indianmeal moth) and Stegobium paniceum (drugstore beetle) are two of the most common insects in dried fruits, nuts, grain products, herb teas or spices. All the stages of both these insects were held at-10,-14 and-18°C for 5 to 480 min and the survival noted. The following times and temperatures were required to control all stages: P. interpunctella; 480 min at-10°C (1 % survival of eggs), 240 min at-14°C, 60 min at-18°C; S. paniceum; over 480 min at-10°C, over 240 min at-14°C, 60 min at-18°C. For P. interpunctella, eggs were the most cold hardy stage. For S. paniceum, adults were the most cold hardy stage with the exception of –14°C, where about 10 % of the eggs but no adult beetles survived 240 min of exposure