Figure 1.
Crossing design and reproductive phenotype of the F1, F2 and F3 progeny.
The name of each lineage is shown below the aphid picture and the color of the aphid picture stands for the reproductive phenotype of each lineage used as parent in crossings (grey for obligately parthenogenetic [OP] and black for cyclically parthenogenetic [CP]). The lines show which individuals were crossed (the cross ID is shown below), plain lines indicating that the lineage was used as female and dotted lines, as male. For each cross, the number of progeny determined as CP and OP is also shown. Only crosses 3 to 7 were included in the QTL analyses (crosses 8 and 9 - identified with an asterisk - were not used because progeny was selected according to genotype at the candidate region and was genotyped only at a subset of markers).
Figure 2.
Localization of the genomic region controlling reproductive phenotype on genetic maps of the pea aphid.
On these maps of each chromosome (LG1 to LG4), we show results from two independent approaches to identify genomic regions that control reproductive mode variation (i.e. the production of sexual females) in the pea aphid. 1) QTL approach: Likelihood ratio (LR) along chromosomes for the presence of a QTL are shown (solid blue curves correspond to LR values for % of sexual females, and solid black curves to LR values for occurrence of sexual females). The LR thresholds corresponding to a p-value of 0.05 at the genome-level (i.e. adjusted for multiple testing) are also shown (dashed blue line for % of sexual females and dashed black line for occurrence of sexual females). Threshold lines for the two traits are almost superimposed. The blue and black bars show the location of the 95% CI of the QTL for % of sexual females and occurrence of sexual females, respectively. 2) Population genomic approach: a hierarchical genome scan was performed using ARLEQUIN 3.5 to identify genomic regions involved in reproductive mode variation. The genetic differentiation values (FCT) among three OP and three CP populations are shown along chromosomes. Loci identified as significant outliers (hence candidate loci for reproductive mode variation) at 1%, 5% or 10% are shown in red, orange and yellow, respectively, and non-outlier markers with a cross. The black line corresponds to a moving average on FCT (calculated on a 15 cM window).
Table 1.
Reproductive phenotype of F2 and F3 individuals according to their genotype in the candidate region.
Table 2.
Outlier loci identified by genome scans.