Figure 4

Principal component analyses (PCAs) of the N. ceranae haplotypes frequencies in A. mellifera isolates from the South West Indian Ocean (SWIO). Honeybees were sampled in La Réunion (blue), Mauritius and Rodrigues (green), the Comoros archipelago (orange), the Seychelles archipelago (pink) and Madagascar (red). Outgroup from Europe (grey) and from A. ceranae and A. dorsata in Thailand (black) were included. For details on the isolates, see Table 1. (a) PCA of all the 636 haplotypes, whatever their frequency, representing 83 coding and non-coding genetic markers from the 7 considered groups. The three first components represented 52.7% of the variance. (b) PCA (53.7% of the variance represented) of the 636 haplotypes from the SWIO isolates, i.e. without the outgroups. (c) PCA (53.7% of the variance) of the 305 major haplotypes from the SWIO isolates. (d) PCA (57.3% of the variance) of the 274 haplotypes, whatever their frequency, representing 43 coding markers from the SWIO isolates. (e) PCA (56.1% of the variance) of the 362 haplotypes, whatever their frequency, representing 29 non-coding markers from the SWIO isolates. (f) PCA (68.4% of the variance) of the 142 haplotypes, whatever their frequency, representing 11 microsatellites markers from the SWIO isolates.