Effect of Anaerobiosis on Glycerol Formation in Larvae of the Rice Stem Borer, Chilo suppressalis WALKER

Abstract

Effect of anaerobiosis on glycerol formation was investigated in developing and dia pausing larvae of the rice stem borer, Chilo suppressalis WALKER. Glycerol accumulation was stimulated in both the pre-diapausing and diapausing larvae exposed to hypoxia, especially to 20% nitrogen-air mixed gas and the accumulation was gradually reduced with increasing nitrogen rates. On the other hand, glycerol formation could not be detected in developing larvae incubated anaerobically. This fact was also confirmed by experiments using ¹⁴C-glucose and ¹⁴C-glucerol. Lactic acid content was increased in developing larvae exposed to nitrogen gas, but was not increased so much in diapausing larve. Pyruvic acid content decreased with increase in lactic acid content. These metabolisms were greatly dependent on the activites of α-glycerophosphate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase and lactate dehydrogenase. Anaerobic metabolism changed according to physiological state of larvae and environmental temperatures.