Figure 3 Results of STRUCTURE based on nrDNA and cpDNA samples of Primulina heterotricha populations collected in 2016 and 2022.
The Bayesian clustering using cpDNA sequences was somewhat different compared to the nrDNA (Figures 3c and 3d), as there were only two genetic clusters (K = 2) (Figures S1c, S1d), suggesting that the dam acts as the main genetic barrier in both datasets. The first cluster included all the populations except JF (i.e., group SW) and partially XA (i.e., group S) for the 2016 dataset, while six years later the population XA fell within the second cluster.
AMOVA results showed that most ITS genetic variation resides among the four regions (Table 4), although this component declined from 71% (2016) to 62% (2022), and the within-population component increased from 9% (2016) to 16% (2022). CpDNA genetic variation residing among regions increased from 2016 (72%) to 2022 (90%), and, unlike the nrDNA, the within-population component decreased from 10% (2016) to 4% (2022).