Adult plasticity of cold tolerance in a continental-temperate population of Drosophila suzukii. (August 2015)

• Record Type: Journal Article
• Authors: Jakobs, Ruth; Gariepy, Tara D.; Sinclair, Brent J.
• Is Part Of: Journal of insect physiology. Volume 79(2015:Aug.)
• Page Start: 1
• Page End: 9
• Publication Date: 2015-08
• Subjects: Cold tolerance -- Winter -- Phenotypic plasticity -- Chill coma -- Spotted wing drosophila -- Fluctuating thermal regime; Insects -- Physiology -- Periodicals; Insectes -- Physiologie -- Périodiques; Insects -- Physiology; Periodicals; 571.157
• DOI: 10.1016/j.jinsphys.2015.05.003
• Languages: English
• ISSNs: 0022-1910

Abstract

Graphical abstract: Highlights: Adult Drosophila suzukii are chill-susceptible and die around −7 °C. They can remain active at relatively low temperatures. Fluctuating-temperature acclimation significantly improves cold tolerance. Adult plasticity is likely insufficient for overwintering in cool-temperate zones. Abstract: Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a worldwide emerging pest of soft fruits, but its cold tolerance has not been thoroughly explored. We determined the cold tolerance strategy, low temperature thermal limits, and plasticity of cold tolerance in both male and female adult D. suzukii . We reared flies under common conditions (long days, 21 °C; control) and induced plasticity by rapid cold-hardening (RCH, 1 h at 0 °C followed by 1 h recovery), cold acclimation (CA, 5 days at 6 °C) or acclimation under fluctuating temperatures (FA). D. suzukii had supercooling points (SCPs) between −16 and −23 °C, and were chill-susceptible. 80% of control flies were killed after 1 h at −7.2 °C (males) or −7.5 °C (females); CA and FA improved survival of this temperature in both sexes, but RCH did not. 80% of control flies were killed after 70 h (male) or 92 h (female) at 0 °C, and FA shifted this to 112 h (males) and 165 h (females). FA flies entered chill coma (CTmin ) at approximately −1.7 °C, which was ca. 0.5 °C colder than control flies; RCH and CA increased the CTmin compared to controls. Control and RCH flies exposed to 0 °C for 8 h took 30–40 min to recover movement, but this was reduced to <10 min in CA and FA. Flies placed outside in a field cage in London, Ontario, were all killed by a transient cold snap in December. We conclude that adult phenotypic plasticity is not sufficient to allow D. suzukii to overwinter in temperate habitats, and suggest that flies could overwinter in association with built structures, or that there may be additional cold tolerance imparted by developmental plasticity.