Molecular diversity of benthic diatoms in intertidal mudflats of the west coast of Korea

Abstract

Identification and classification of benthic diatoms are one of the most challengeable tasks because of its morphological similarity and complexity with small size of cell. In present study, we isolated and developed 64 strains of benthic diatom from several sampling stations of intertidal mudflat, in the west coast of Korea. The new strains were represented 56 species of 14 genera, and subjected to molecular analyses using two different genes (i.e., rbcL and 18S rDNA), as well as various morphological analyses. Most of strains belong to the Bacillariaceae (23 strains) and Naviculaceae (21 strains) family groups, including 20 newly identified species. The rbcL and 18S rDNA sequences were useful to identifying 8 and 12 strains, respectively. Genetic distances (P-distance) of rbcL and 18S rDNA compared in the genus and family levels of each group. In the nitzschoid diatom group, Bacillaria and Cylindrotheca were monophyletic, however, Nitzshia andTryblionella were polyphyletic. Naviculoid diatoms group includes monophyletic Haslea, Gyrosigma, Pleurosigma and Navicula. Two tube dwelling diatoms (i.e. Berkeleya and Parlibellus) were grouped within asymmetrical biraphid diatoms comprising of the genus Entomoneis and Petrodictyon. These results will useful for better understandings on molecular and morphological diversity studies of benthic diatoms.iatom from several sampling stations of intertidal mudflat, in the west coast of Korea. The new strains were represented 56 species of 14 genera, and subjected to molecular analyses using two different genes (i.e., rbcL and 18S rDNA), as well as various morphological analyses. Most of strains belong to the Bacillariaceae (23 strains) and Naviculaceae (21 strains) family groups, including 20 newly identified species. The rbcL and 18S rDNA sequences were useful to identifying 8 and 12 strains, respectively. Genetic distances (P-distance) of rbcL and 18S rDNA compared in the genus and family levels of each group. In the nitzschoid diatom group, Bacillaria and Cylindrotheca were monophyletic, however, Nitzshia andTryblionella were polyphyletic. Naviculoid diatoms group includes monophyletic Haslea, Gyrosigma, Pleurosigma and Navicula. Two tube dwelling diatoms (i.e. Berkeleya and Parlibellus) were grouped within asymmetrical biraphid diatoms comprising of the genus Entomoneis and Petrodictyon. These results will useful for better understandings on molecular and morphological diversity studies of benthic diatoms.