Abstract
The effect of temperature on the growth of Lasioderma serricorne (F.) individually reared on bread crumbs was studied. The insect was kept at 20, 22.5, 25, 27.5 and 30°C, and at a relative humidity of 70% with alternating 16-hr light and 8-hr dark cycles. The mean values for the preadult development period were 217 days at 20°C, 94 days at 22.5°C, 81 days at 25°C, 62 days at 27.5°C and 57 days at 30°C, respectively. At lower temperatures the developmental velocity decreased and the mortality increased. The regression equation between the developmental velocity and temperature was Y=0.0013X-0.0192 in the developmental period. The developmental zero corresponded to 15.0°C and the total effective temperature was estimated to be 781.9 day-degrees. The frequency of larval moulting increased at lower temperatures: four moults were observed mostly between 22.5°C and 30°C, and five moults at 20°C. The head of the final instar larva was wider at lower temperatures than at higher temperatures, and the largest value was found in the larvae reared at temperatures ranging between 22.5°C and 25°C. The mean growth rate of the larval head width was lowest in larvae with five moults (1.34) and highest in larvae with three moults (1.54).
