The lifespan of starving flies of different Drosophila melanogaster stocks: effects of caffeine and He-Ne laser light

Abstract

Aim. Analysis of the chronic effects of caffeine and laser radiation on starvation resistance in Drosophila melanogaster, in depends on the genotype. Methods. The experiments were carried out in wild type stocks of Drosophila melanogaster: Canton-S and Oregon; mutant stock ebony and stocks with mutation ebony saturated by stocks Canton-S and Oregon – ebonyC-S and ebonyOr. Caffeine was applied in concentration of 0.5 mg/ml in the cultural medium. Flies were exposed to He-Ne laser light of wavelength 632.8 nm and surface power density 0.03 mW/cm2 for 5 minutes. Control flies were grown under standard living conditions. Results. The lifespan during starvation dependence on a genotype (17.62 % and 19.51 %), external factors (h = 17.02 % and 19.64 %) and on the combined factors – h = 4.37 % and 2.42 % (for males and males, respectively) was shown. Conclusions. Almost in all experimental variants caffeine and laser light induced the extension lifespan during starvation. The simultaneous applying of both factors (caffeine+laser light) induced the maximal lifespan extension in Drosophila stocks C-S, ebony, and ebonyOr. Such additive effect was not observed in ebonyC-S flies. We connect the observed effects of caffeine and laser light with hormesis effect.Keywords: drosophila, genotype, lifespan during starvation, mutation, stress tolerance.