DNA Barcoding Of Da Xinggan Ling

DNA barcoding is a new technique that uses a short DNA sequence from a standardized and agreed-upon position in the genome as a molecular diagnostic for species-level identification, it is an effective complement for traditional taxonomy based on morphology.In this study, we used DNA barcoding as a tool for identifying plants that we could not identify by the traditional taxonomy. We also aimed to test the effectiveness of different candidate barcodes for identifying plants at Da Xinggan Ling.1. It is very important but usually difficult to extract highly quality DNA from plants for molecular work since there exist a great deal of polysaccharides, hydroxybenzenes, esters and other secondary metabolites. We provide a simple modified CTAB (mCTAB) protocol for extracting plant DNA. We compared our protocol with four frequently use3and commercially available kits. The result showed that our mCTAB method yielded much more DNA of high quality that is suitable for PCR amplification but with much lower cost.2. We identified22plants that we could not identify by the traditional taxonomy. After extracting DNA,PCR amplification, statistical analysis,8plants were identified at species level,9plants were identified at genus level and5plants were identified at family level.3. We identified42plants that we could not identify by the traditional taxonomy in Poaceae. After extracting DNA,PCR amplification, statistical analysis,5plants were identified at species level,29plants were identified at genus level.4. We tested the applicability of four DNA regions (matK,rbcL,ycfl and ITS) as the barcodes to identify species at Da Xinggan Ling. Based on assessmenting of the success rates of PCR amplification, the extent of specific genetic divergence,the DNA Barcoding Gap and the ability for species discrimination, our results suggestde that ycfl was the best of the four loci tested for identifying plants at Da Xinggan Ling.matK and ycfl could be used to identify plants as candicate DNA barcodes.