Population-specific patterns of longevity and thermal induced lifespan extension in Drosophila suzukii

Drosophila suzukii is an invasive pest that damages fruits of soft skin, provoking economic losses for commercial fruit producers. Understanding its biology is key for developing pest management strategies, with particular attention to life-history traits such as longevity and thermal tolerance. While previous studies mainly analyzed temperature effects on longevity, response to sub-lethal thermal treatments and its potential beneficial effects on longevity have not been explored. We examined thermal induced changes in longevity and explored heat and cold tolerance in two D. suzukii stocks derived from climatically different regions of Argentina. Longevity was assessed at two constant temperatures (25 and 30 °C) and at 25 °C with either a heat or a cold-stress treatment. Differences in mean longevity between populations were dependent on temperature regimen and thermal-stress treatment, with differences being significant at 25 °C both with and without a heat-stress. A reduced longevity was observed for flies of both stocks exposed at constant 30 °C. Longevity extension induced by heat was found in flies from the temperate/subtropical region which were also the shortest-lived flies at 25 °C. No effects of the cold-stress treatment on longevity were observed. Regarding thermal tolerance, flies from the cold region were more heat-susceptible and recovered faster after cold-stress than flies from the temperate/subtropical region. Our results evidence heat-induced lifespan extension in D. suzukii and suggest that this phenomenon could be an important aspect of population phenotypic plasticity for this species.