Fig. 2. Evolution of the H. citrina genome and gene families.

a Phylogenetic tree of 19 plant species and the sizes of expanded and contracted gene families: A. trichopoda, M. cordata, P. mume, T. cacao, A. thaliana, C. sinensis, R. williamsianum, C. arabica, S. tuberosum, P. nil, L. japonica, C. nankingense, Z. mays, O. sativa, D. catenatum, P. equestris, A. officinalis, A. sativum, and H. citrina. b The distribution of single-copy, multiple-copy, unique, other orthologous and unclustered genes in the 19 plant species. c Distribution of Ks values between L. japonica, A. thaliana, A. officinalis, S. tuberosum, and H. citrina (Ks distribution chart showing that H. citrina experienced a relatively recent WGD event). d Dot plots of paralogs in the H. citrina genome