Vol.17. Nos.1 (2018) pp.1-10
Title:

Limitations of the Recommended DNA Barcode Regions in Slow Evolving Plants: A Case Study of Rattans in the Western Ghats of India

Authors:Anoja Kurian, SumaArun Dev, Sreekumar V. B., Muralidharan E. M.

Abstract:Presence of environmental plasticity, homoplasies, look-alike species and species complexes, makes morphology based identification within genus Calamus very complicated. DNA barcoding is employed to enable accurate species identification within this genus in order to resolve these taxonomic complexities. We investigated the species discriminatory power of standard barcode loci (rbcL, matK and psbA-trnH) and their different combinations (rbcL+matK, matK+psbA-trnH, rbcL+psbA-trnH, rbcL+matK+psbA-trnH) using distance and similarity based analyses for 20 species of Calamus found in Western Ghats of India. In the present study standard DNA barcodes could not discriminate Calamus species. rbcL sequences did not show any nucleotide differences while barcoding gap exhibited by matK and psbA-trnH barcode regions and their combinations is not significant enough for successful species delimitation. The candidate DNA barcode regions adopted in the analysis failed to provide species- specific DNA barcodes, due to slow evolutionary rate in palms. This necessitates the need to explore new barcode regions other than plastid regions to delimit species boundaries in genus Calamus. Fast evolving regions like low copy nuclear regions can be exploited for their ability in species discrimination.

Keywords:Calamus, palms, lowcopynuclearregion, DNA barcoding, species discrimination

Permalink: https://www.jbronline.org/article.asp?id=293