Phylogeny of Weigela and Diervilla (Caprifoliaceae) Based on Nuclear rDNA ITS Sequences: Biogeographic and Taxonomic Implications

摘要: and three species of Diervilla were inferred from nucleotide sequence variation in the internal transcribed spacer (ITS) regions 18-26S nuclear ribosomal DNA. Phylogenetic trees obtained using parsimony, distance, maximum likelihood methods. The ITS phylogenies did not support monophyly Weigela, which comprises major clades. first clade includes a single species, W. middendorffiana, is more closely related with American genus, Diervilla. second consisted maximowiczii, but its relationship to other Weigela equivocal. third one strongly supported core contains remaining species. Within group, hortensis exhibits most distinct type. hybrid origin putative parents, florida subsessilis, supported. evidence favors taxonomic hypothesis proposed by Nakai who recognized four evolutionary lines (Diervilla, Macrodiervilla, Weigelastrum Weigela). However, recognition two sections, Calysphyrum was phylogenies. Substantial morphological differences between middendorffiana do stasis concept has been considered as general mode among Asian North disjunct taxa.