Accessions of Kolkwitzia amabilis Graebn. of wild origin with collection information and cultivated sources with or without collection information were grown under the same environments to observe the differences in morphology and flowering time. The morphological variation was further documented by analyzing the nuclear internal transcribed spacers 1, 2 in ribosomal RNA gene (ITS 1, 2 region) and randomly amplified polymorphic DNA (RAPD) markers. US National Arboretum accession NA64889 of wild origin with collection information (known wild origin) flowered earlier than cultivated sources with (cultivars of known wild origin) or without (cultivars of unknown wild origin) collection information for two years. However, significant variations were observed in sequences of the polymerase chain reaction (PCR) products of all clones of all accessions with the exception of AA20447C. Four out of five clones of NA64889 showing haplotype H were together in the same sub-clusters separated from other accessions. We conclude that NA64889 of known wild origin that flowers early was different from other accessions of cultivated sources of known wild origin (AA816-84A) or of unknown wild origin (AA20447 and AA181-2005). Moreover, the analysis performed on the on the ITS 1, 2 region sequence and RAPD markers were shown that all accessions of cultivated origin, analyzed in this study, are derived from germplasm of known wild origin (AA816-84A).
