Juvenile Hormone Involvement in Pupal Diapause of the Flesh Fly Sarcophaga Crassipalpis: Regulation of Infradian Cycles of O2 Consumption

Abstract

1. A cyclic pattern of juvenile hormone (JH) activity is retained during pupal diapause in the flesh fly, Sarcophaga crassipalpis. 2. Cycles of JH activity correlate with infradian cycles of O2 consumption. JH activity progressively increases during a 4-day cycle and appears to trigger the onset of an M02 peak. 3. During the first 2 days of an MOO2 cycle, pupae are insensitive to an application of JH analogue, but when JH analogue is applied during the last 2 days of the cycle, M02 rises and the cyclic M02 pattern is destroyed. When JH analogue is applied to third instar larvae, O2 consumption is sustained at a steady, high rate throughout pupal diapause. 4. The MOO2 cycles persist in abdomen-ligated pupae but disappear following head ligation.