Effect of low rearing temperature on development of Galleria mellonella larvae and their sensitivity to juvenilizing treatment

Abstract

1. 1. The development of Gallena mellonella is strongly affected by a low temperature of 18°C (the last instar persists for more than one year, instead of about 9 days at 30°C). At 18°C the last instar Galleria mellonella larvae respond to juvenilizing treatment—chilling stress or juvenile hormone analogue—with a very low percentage or no supernumerary moults, respectively. 2. 3. Experiments in which larvae subjected to such treatments were transferred from 18°C to 30°C and vice versa showed that for the realization of the larval programme after chilling stress application the higher (30°C) temperature is needed. 3. 4. In last instar larvae reared at 18°C there coexist very high juvenile hormone titre and high juvenile hormone esterase activity. 4. 5. This phenomenon which is found in both, chilled and unchilled larvae, is discussed.