In an experimental approach fruit and vegetable puree was inoculated with allochthonous and autochthonous fly fecal microbiota to record life-history parameters (time until eclosion and weight upon eclosion) of single Drosophila melanogaster flies. The experimental set up was repeated 5 times between March 2020 and November 2021 at the laboratory facilities of University of Bremen, Germany. Maternal microbiota are crucial for Drosophila melanogaster larval development in ephemeral breeding substrates. However, microbiota are known to vary in composition based on the nutritional substrate of the maternal flies (Riedel & Rohlfs, in preparation). Here we collected data on life-history traits of flies developing in different plant substrate and fly-microbiota combinations, to assess fitness outcomes under autochthonous (microbiota collected from a microcosm with same plant substrate) and allochthonous (microbiota collected from microcosm with different plant substrate) developmental conditions. Microbiota was collected as fecal material of 30 gravid female flies in 15 mL screw-cap tubes overnight and subsequently washed into a suspension with 5 mL of sterile Phosphate buffered saline. In a 2 mL collection tube, 1 mL of plant substrate (apple, banana, cucumber, lemon and tomato) was inoculated with 50 µL of fly fecal microbiota suspension; or 1 mL of artificial lab diet was used without microbiota inoculation. Single axenic first instar larvae, collected as eggs from an outbred Drosophila melanogaster population (Wölfle et al., 2009) were added gently, using a sterile brush. Larvae that succumbed due to the procedure were excluded. Freshly eclosed flies were dried over silica gel and weighed on a precision scale (SE2 ultra-micro balance, Sartorius AG). In the first run of the assay development time and weight of individual flies could not be linked and are thus presented separately with the respective column "Weight" or "Days_to_adult" empty. To further emphasize this missing link "Identifier" is only given with Treatment number for the first set of the overlapping samples that include development time information. Information on microbiota community is included in Riedel and Rohlfs (in preparation), Riedel et al. (preprint, https://doi.org/10.1101/2025.10.14.682149) and raw sequences may be accessed at European Nucleotide Archive (ENA) at EMBL-EBI under accession number PRJEB96953 (fungal) and PRJEB96936 (bacterial).

Funded by the State of Bremen