Raw data used in: Variations in effects of ectosymbiotic microbes on the growth rates among different species and genotypes of Daphnia fed different algal diets

<p>Several recent studies have shown that ectosymbiotic bacterial microbiota, including gut microbes, affect the growth and reproduction of <span class="MsoSubtleEmphasis">Daphnia</span>, a key organism in lake ecosystems. However, these studies examined specific species, such as the model organism, <i>D. magna,</i> and used green algae as food. It is unclear if symbiotic bacteria affect fitness in other <span class="MsoSubtleEmphasis">Daphnia</span> species common in lakes and ponds in Japan. In this study, we examined the growth rates of sterilized individuals of two <i>D. pulex</i> genotypes with <i>D. magna</i> using the green algae <i>Scenedesmus</i> and the diatom <i>Cyclotella</i> as algal diets. In addition, we examined the growth rate of the sterilized <span class="MsoSubtleEmphasis">Daphnia</span><i> pulex</i> individuals infected by <i>Limnohabitans</i> spp., previously reported to promote the fitness of <i>D. magna</i> as ectosymbiotic bacteria. We found that the effects of ectosymbiotic bacteria on growth rate differed not only between different genotypes of <i>D. pulex</i> but also between individuals fed the different algal diets. The results suggest that the genotype- and diet-specific differences in fitness-dependency on the ectosymbiotic microbiota can be factors affecting the genetic structures of <i>D. pulex</i> populations.</p>