Supercooling and freezing as eco-physiological alternatives rather than mutually exclusive strategies: A case study in Pyrrhocoris apterus

0495566 - BC 2019 RIV GB eng J - Článek v odborném periodiku
Rozsypal, Jan - Košťál, Vladimír
Supercooling and freezing as eco-physiological alternatives rather than mutually exclusive strategies: A case study in Pyrrhocoris apterus.
Journal of Insect Physiology. Roč. 111, NOV-DEC 2018 (2018), s. 53-62. ISSN 0022-1910. E-ISSN 1879-1611
Institucionální podpora: RVO:60077344
Klíčová slova: Insects * supercooling * freeze tolerance
Obor OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology
Impakt faktor: 2.862, rok: 2018

Overwintering insects are categorized either as freeze tolerant or freeze avoiding(supercooling). Some supercooling insects, however, were found to survive in frozen state when freezing occurred through inoculation by external ice at mild subzero temperatures. We assessed the potential relevance of inoculative freezing and freeze tolerance strategy in an insect that was so far considered as a classical example of a ‘supercooler’, the linden bug (Pyrrhocoris apterus). Here we show that: 1) overwintering microhabitat of P. apterus presents a high risk of inoculative freezing, 2) overwinering P. apterus will readily freeze when in contact with external ice, 3) inoculatively frozen insects will survive, 4) the limits of freeze tolerance are set by the critical fraction of ice, and 5) the evolution of overwintering strategy in P. apterus might have been driven, at least partially, by a necessity to seasonally suppress the actual ice fraction below the critical ice fraction. Since many insect species overwinter in habitats similar to that of P. apterus, the ability to tolerate freezing after inoculation by external ice crystals could be much more common among ‘supercooling’ insects than it is currently appreciated.

Trvalý link: http://hdl.handle.net/11104/0292233