关键词: ITS, matK, 形态分类学

Abstract: DNA barcoding is a new biological tool for accurate, rapid and automated species identification by use of short, standardized genes or DNA regions that can be amplified easily by PCR. Although DNA barcoding involves controversial theoretical and practical aspects, it has received considerable attention since Paul Hebert proposed the concept in 2003. The research into and application of DNA barcoding in plants is still in its early exploration stage and is inferior to that in animals. Three underlying problems for plant DNA barcoding still persist. First, no consistent criteria exist for the selection and assessment of barcodes. Second, research into DNA barcoding based on thorough morphological taxonomic revision is necessary but is lacking. Third, previous studies in plants were mainly carried out on a large scale, with only a few species within one genus and single or few individuals from the same species sampled, which resulted in a superficially high rate of discrimination and low credibility of the reference database. Until now, rbcL and matK are undoubtedly the most useful barcodes and provide a universal framework for land plants at and above generic levels. However, they do not provide enough informative sites to identify all the species within some genera, in particular those with recent rapid radiation. Thus other markers with faster evolutionary rate than these 2 genes are needed, although the plant working group of the Consortium for the Barcode of Life has recommended the 2-locus combination of rbcL and matK as the barcode for plants.

Key words: internal transcribed spacer, matK, morphological taxonomy