Fig. 4. Olfactory pathways required for D. sechellia oviposition.

a Single-fly oviposition preference assays for noni juice versus apple cider vinegar in agarose for the indicated genotypes (Supplementary Table 1). The plots show the number of eggs laid per fly; N = 30–60 flies across 1-2 technical replicates. DsecIr75b^1/2 is a transheterozygous mutant combination. b Quantification of the number of eggs and indentations on different substrates of the indicated genotypes; N = 30 (Dsec 07) and 58 (DsecIr8a^GFP;Orco¹) across 1-2 technical replicates. c Mean number (± SEM) of mature eggs per fly (i.e., a pair of ovaries) of the indicated genotypes. NS P > 0.05 (two-sample t-test); N = 9–10 flies. d Left: oviposition preference index for the assays shown in a. Statistically-significant differences from 0 (no preference) are indicated: ***P < 0.001; **P < 0.01; *P < 0.05; NS P > 0.05 (Wilcoxon test with Bonferroni correction for multiple comparisons); N = 30–60 flies across 1-2 technical replicates. Dsec 07 and DsecIr8a^RFP are statistically-significantly different: P = 0.0328 (Wilcoxon test with Bonferroni correction). Right: egg-laying rate. Statistically-significant differences from the Dsec 07 strain are indicated: ***P < 0.001; *P < 0.05; NS P > 0.05 (Kruskal-Wallis rank sum test with Nemenyi post-hoc test). The non-significant preference index for the DsecIr8a^GFP,Orco¹ double mutant was calculated from the 4/60 animals that laid >2 eggs. Exact P values for the statistical comparisons are provided in the Source Data files.