DNA barcoding of the invasive alien aquatic weed Heteranthera reniformis Ruiz and Pavon using chloroplast DNA markers

Abstract Morphology-based species identification may not be accurate and necessitates extensive taxonomic knowledge. Regarding Heteranthera reniformis Ruiz and Pavon, an invasive alien species in Japan, it is difficult to find appropriate information on molecular data. DNA barcoding is a convenient method of identifying species based on the nucleotide diversity of conserved sequences. In this study, we aim to assess the suitability of chloroplast maturase K ( matK ) and ribulose-1,5-bisphosphate carboxylase large ( rbcL ) as DNA barcode markers by collecting molecular data and comparing them with related species available in the gene bank. Both matK and rbcL markers exhibited a 100% success rate in their amplification and sequencing, with gene sizes of 833 bp and 552 bp, respectively. The subsequent sequence analysis confirmed biological homology with closely related species. The highest homology of 99.52% in the matK sequence was found with H. callifolia . Moreover, the rbcL sequence showed a higher homology of 99% with seven species of the same family. This study highlights the utility of both chloroplast gene regions as barcode primers in elucidating fundamental molecular aspects of H. reniformis plant.