Species-specific SCAR markers for authentication of Sinocalycanthus chinensis

Sinocalycanthus chinensis, an endangered species endemic to China, is cultivated as an ornamental landscape tree in China. However, S. chinensis, Chimonanthus species and Calycanthus floridus are difficult to be distinguished in seedling market because of their similar morphological characters. In this study, ISSR (inter-simple sequence repeats) were applied to detect S. chinensis from its closely related species. A unique 748-bp band was found in all accessions of S. chinensis. SCAR (sequence characterized amplified regions) markers were created by cloning and sequencing the specific band, and designing a pair of primers to amplify the band of 748 bp. Diagnostic PCRs were performed using the primer pair with the total DNAs of S. chinensis, Chimonanthus species and C. floridus as templates, with only S. chinensis being able to be amplified. This amplification is not only rapid (results can be obtained in less than 3 h), but is also easy to perform. Hence it is a feasible method for identifying S. chinensis in seedling market.