Figure 2

The phylogenetic tree of 535 R genes in S. italica. The tree was built with the maximum-likelihood algorithm by MEGA software. The red full circles denote S. italica specific R genes, i.e., S. italica R genes that have no syntenic orthologs in any of the other 11 grass species. Branches colored in orange are R genes from tandem duplication arrays, others are R gene singletons.