Identification of S-RNase sequences in Petunia. a) A maximum likelihood phylogenetic tree of the Petunia S-RNase sequences generated by Nanopore sequencing with five Antirrhinum ones as outgroups. The percentage of 1,000 bootstrap replicates are shown on the branches when ≥90%. Assigned names of S-alleles are also shown. b) Pair-wise genetic distance between S-RNase sequences. Distances between different and the same S-allele pairs are indicated by red and blue, respectively. The distributions of genetic distances for within and between S-alleles were significantly different (P < 2.2 × 10−16, Wilcoxon rank-sum test). c) Nucleotide diversity along the coding region of the S-RNase genes (blue line) and positively selected sites (red vertical lines). Gray shaded areas indicate hypervariable regions I and II.
