Fig. 2

Evolution of the I. trifida genome and gene families. a Phylogenetic tree showing the divergence times of eight species. The blue dots represent WGD events, and the red dots represent WGT events. The grey circles indicate the genome sizes of the eight species. b Distribution of 4dTv values of syntenic genes. The dotted lines represent comparisons of each species with its own sequences, and peaks indicate genome duplication/triplication events. The solid peaks indicate divergence events between species. Itr: I. trifida, Stu: S. tuberosum, Cca: C. canephora, Ini: I. nil. c The large circle shows I. trifida - I. trifida intragenomic syntenic regions putatively derived from WGT, which were detected by a series of paralogous genes (only chromosomes 4, 9, 13 and 15 are shown). The bottom circle shows collinear blocks between chromosome 1 of C. canephora and chromosomes 6, 7 and 11 of I. trifida. The right circle shows collinear blocks between chromosome 4 of C. canephora and chromosomes 5, 12 and 13 of I. trifida. The colour of each link corresponds to the colour of the chromosome. d The expansion of gene families associated with SR in I. trifida