LARVAL DIAPAUSE IN FANNIA CANICULARIS (L.)

Abstract:
When parent adults were kept and allowed to oviposit at 20'C in a long day (14L:lOD) regime, and the eggs and hatching larvae were reared at 20°C under the same conditions or in darkness, no or very few (less than 12%) fully-grown larvae entered diapause. When parent adults were kept and allowed to oviposit at 20'C and in a short-day (8L:16D or 10L:14D) regime, the incidence of larval diapause under the same condition or in darkness was high (usually 32% to 100%). This suggests that the short-day regime, especially in parent flies, is an important diapause inducing factor for fully grown larvae of F. canicularis. Chilling treatment of diapausing larvae at 6'CXC, longer than enough to terminate the larval diapause, allowed the larvae to pupate under the chilling temperature, even giving rise to emergence of a few adults at between 127-134 days. More than 30% of non-diapause pupae could emerge into adults under the same chilling temperature.