Phylogenetic relationships of sequence variants of CEVd and HSVd. The CEVd (A) and HSVd (B) sequence variants were obtained from Taiwan and the representative isolates of the world. Trees were constructed by MEGA 6.0 using the neighbor-joining method with 1000 bootstrap replications. Potato spindle tuber viroid (PSTVd) from the same family Pospiviroidae (KF418767.1) was as outgroup. Bars indicated numbers of nucleotide substitutions per site.