The Fate of 14C-Glycerol in the Rice Stem Borer, Chilo suppressalis WALKER (Lepidoptera : Pyralidae)

The interconversion between glycogen and glycerol was examined during diapausing and post-diapausing stages by injecting 14C-glycerol.Redioactive glycerol injected was rapidly incorporated into glycogen in diapausing larvae at 25°C even during increase of glycerol, showing that the interconversion between glycogen and glycerol may easily occur on warmer days in winter. However, this interconversion proceeded in the direction of glycerol synthesis at such low temperature as 4 °C.The isotope injected was incorporated into various tissues to varying degrees, especially it was found predominantly in fat body glycogen.The degradation rate of 14C-glycerol in diapausing larvae was lower than in post-diapausing larvae. On the other hand, in non-diapausing larvae which were shown to contain no glycerol, 14C-glycerol was rapidly degraded in comparison with hibernating larvae. A cause of no glycerol accumulation in non-diapausing larvae may be attributed to such high activity of glycerol degradation.