The photoperiodic regulation of larval growth and pupation in the large mealworm Tenebrio molitor L. (Coleoptera, Tenebrionidae)
Tyshchenko, V.P.; Ba, A.S.
Entomologicheskoe Obozrenie 65(1): 3-12
The rates of growth and the dynamics of pupation of the larvae of Tenebrio molitor at 20 and 25 degrees C were shown to be controlled by a 2-peaked photoperiodic reaction. At 25 degrees C, a 12-h day induced pupation of all larvae in the 2 months following the formation of the first pupae. In other light regimes, some larvae (37.3-76.5%) pupated after a longer interval. The photoperiodic reaction controlled not only the initiation of the delay in pupation but also its duration. A long-day photoperiod caused a longer delay than a short-day one. Temperature had a strong modifying effect on the photoperiodic reaction. An inversion of the photoperiodic response occurred at 30 degrees C: a 12-h day delayed pupation, but long-day (18 h) and entire-day illumination had a stimulatory effect.