Institute of Medicine, M.K. Ammosov North Eastern Federal University, Kulakovskogo Street 36, Yakutsk, Sahka Republic (Yakutia) 677007, Russia. Electronic address: li_natalia@mail.ru.
Source
Comp Biochem Physiol A Mol Integr Physiol. 2020 04; 242:110649
Low temperatures limit the distribution and abundance of ectotherms. However, many insects can survive low temperatures by employing one of two cold tolerance strategies: freeze avoidance or freeze tolerance. Very few species can employ both strategies, but those that do provide a rare opportunity to study the mechanisms that differentiate freeze tolerance and freeze avoidance. We showed that overwintering pupae of the cabbage white butterfly Pieris rapae can be freeze tolerant or freeze avoidant. Pupae from a population of P. rapae in northeastern Russia (Yakutsk) froze at c. -9.3 °C and were freeze-tolerant in 2002-2003 when overwintered outside. However, P. rapae from both Yakutsk and southern Canada (London) acclimated to milder laboratory conditions in 2014 and 2017 froze at lower temperatures (