Daily changes in the cold sensitivity of Galleria mellonella larvae
Titel:
Daily changes in the cold sensitivity of Galleria mellonella larvae
Auteur:
Bogus, M. I. Cymborowski, B.
Verschenen in:
Biological rhythm research
Paginering:
Jaargang 15 (1984) nr. 1 pagina's 33-43
Jaar:
1984-03
Inhoud:
Cold sensitivity of last instar Galleria mellonella larvae was investigated by measuring (1) the number of extra-larval molts, (2) the number of larvae retaining ability to secrete silk, and (3) the number of larvae showing arrested development, after 2 h exposure to 0°C. Daily changes refer to the production of extra-larval molts only, which are not generated by photoperiod. These variations result from (a) the time of day at which larvae molt from the penultimate into the last larval instar, (b) the sex of larvae, (c) the age of larvae at cooling, and (d) the time of day at which cooling stress was given. The time of molting into the last larval instar determines the sex ratio in the group of molting insects. Because females show higher sensitivity to cooling than males, the general sensitivity of an examined group of larvae is influenced by the time of molting, and sensitivity is increased when females are in majority. The course of the daily changes in the sensitivity to cooling results, in turn, from the age of the larvae and the time of day at which larvae were exposed to low temperature.