Synergistic effects of developmental temperature and rearing diet on the thermal tolerance and performance of a cactophilic Drosophila

KREIMAN LUCAS; SOTO EDUARDO; PELUSO DANIELA; HASSON ESTEBAN; SCHILMAN, PABLO E.; MENSCH, JULIÁN

Rennes

Simposio; 9th International Symposium on the Environmental Physiology of Ectotherms and Plants; 2022

The developmental temperature has a profound effect on the fitness of ectotherms. Also, dietcomposition has been shown to affect a range of relevant characters in these organisms.However, the combined effects of these factors have been rarely tested. The present study willfocus on the combining effect of developmental temperature and rearing diet on the thermaltolerance and performance of the cactophilic species Drosophila buzzatii. Specically, wemeasure chill coma recovery time, as well as the fitness components of juvenile survival,developmental rate and ovariole number at six developmental temperatures to construct thermalperformance curves for each diet. Using these data, we tested the synergy of these factors onthe plasticity of thermal performance and tolerance. Remarkably, we found that only when flieswere reared on a semi-natural diet and under a daily temperaturefluctuation (DTF) (4-16C; mean = 10C) cactophilic flies can complete development in about90 days (duration of winter) and attained a high cold tolerance. Conversely, if flies were rearedunder constant temperature (10C) or on a standard diet (with or without variable temperatures)they failed to complete their development. So, only when more than one natural treatment wasincluded, i.e., seminatural diet and DTF, we found that flies can overwinter as larvae and pupae.The natural diet of necrotic cactus consumed by cactophilic Drosophila combined with winterthermal variability allows overwintering survival and enhanced cold tolerance.