Evaluation of Genetic Diversity by DNA Barcoding of Local Lotus Populations from Thua Thien Hue Province

Abstract

Background: DNA barcoding is a relatively new method of identifying plant species using short sequences of chloroplast DNA. Although there is a large number of studies using barcoding on various plant species, there are no such studies in the genus Nelumbo. Methods: Three chloroplast DNA regions (rbcL, matK, trnH-psbA) were tested for their suitability as DNA barcoding regions of thirty three lotus samples which were collected in Thua Thien Hue province, Vietnam. Universal primers were used and sequenced products were analyzed using Minimum Evolution method in the MEGA 7.0 program.Result: We did not observe high variability in nucleotide sequences within the rbcL region (0.135%). White Nelumbo, while, the most encoding matK (8.013%) and variable trnH-psbA (with different number of repeating regions TAAAA) intergenic regions was the most useful for Nelumbo barcoding. Individual application of the studied regions did not provide the expected results. None of the regions used in the study allowed the division of white and pink lotus varieties of N. nucifera specie according to the adopted classification of the genus Nelumbo. The results confirm that the use of matK, rbcL and trnH-psbA or combine all three regions together is insufficient for DNA barcoding in white and pink lotus varieties of N. nucifera specie and better discrimination within the genus Nelumbo. Our results also indicate the necessity of using a different region. All of the new sequences have been deposited in GeneBank under the following accession numbers: rbcL (MN011708 to MN068956); matK (MN011719 to MN068978) and trnH-psbA (MN011730 to MN086252).