| 【Objective】The identification ability of ITS2, ITS, psbA-trnH,rbcL, matK sequences to Euphorbiaceae
plants in Hainan was compared.【Method】Bidirectional sequencing was conducted on the target sequence of the test
sample by PCR sequencing. Sequence assembly and consensus sequence generation were performed by using Codon Code
Aligner. Phylogenetic study was performed by using software MEGA 6.0 in accordance with Kimura-2-parameter (K2P)
mode. The distribution of intra-specific and inter-specific variation was analyzed by TAXON DNA software and analysis
on DNA barcoding gaps was carried out.【Result】The sequence acquisition rates of the five candidate sequences were
86.96%, 76.81%, 89.86% , 79.71% and 49.28%, respectively. The coefficient of variation and information site coefficient
of ITS2 sequence were the largest. ITS2 sequence had obvious barcoding gap, and the distribution of interspecific and
intraspecific variation tended to be separated on both sides. Although its sequence had barcoding gap, there were more overlap regions between intraspecific variation and interspecific variation. The barcoding gap of psbA-trnH and matK sequences
was not obvious, and there were more overlap regions between intraspecific variation and interspecific variation; while the
barcoding gap of rbcL sequence was not obvious, but the overlap ratio between intraspecific variation and interspecific variation
was small.【Conclusion】ITS2 has strong ability to identify the Euphorbiaceae plants in Hainan, while rbcL can not be used as
a single DNA barcode to identify species, but it can be used as a supplementary for ITS2. |
