Department Of Botany

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    DNA Barcoding, Phylogeny and Phylogeography of Green Sea Weed Ulva from Indian Subcontinent
    (Central University of Punjab, 2019) Rani, Pooja; Bast, Felix
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    Diversity of green and red macroalgee distributed in indian west-coast using morphometry and DNA barcoding
    (Central University of Punjab, 2013) Aijaz Ahmad John; Bast, Felix
    Modern algal systematists exploit genetic tools for molecular assisted alpha taxonomy and DNA barcoding is one such molecular tool that relies on the use of a standardized DNA region as a tag for rapid and accurate species identification. In this study Nuclear Internal Transcribed Spacer (ITS) was used as a marker for identification and phylogenetic analysis of marine green and red macroalgae in Indian subcontinent. Using Bayesian Inference for phylogenetic reconstruction with T3P model of molecular evolution and gamma distribution (T3P+G) using ITS dataset revealed that the bloom forming Ulva intestinalis found in west coast of Indian subcontinent showed strong endemism, supporting the view that that the genus Ulva encompasses a number of endemic cryptic species in addition to cosmopolitan species. Although there were two morphotypes present in Indian isolates, they constituted a single clade with robust Bayesian Posterior Probability support, confirming conspecificity of these morphotypes. Our results also indicate latitudinal gradients in the distribution of tubular Ulva, with a clade encompassing all nontropical isolates. Higher genetic heterogeneity of tropical isolates as evidenced by highest within-group T3P (Tamura-3-Parameter) distances comparing with that of non-tropical isolates is suggestive of tropics being the geographic origin of these species. While U. compressa and U. intestinalis were monophyletic within nontropical superclade, these morphotypes were polyphyletic within the tropical clade. Due to the polyphyly of currently accepted morphospecies concept and formation of distinct phylogenetic clade among Indian isolates forces us to propose a new bloom forming species of Ulva paschima. Further molecular assessment of invasive Carrageenophyte Kappaphycus alvarezii using ITS-1 region showed affinity to phylogenetic clade of mixed geographical origin confirming that the species was introduced in the subcontinent by human intervention. Surprising result of our study was an endophytic green algae Ulvella leptochaete that was found growing inside Caldophora glomerata, a first report of its kind from India.
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    Taxonomic reappraisal of Monostromataceae (Ulvophyceae: Chlorophyta) based on multi-locus phylogeny
    (Taylor and Francis Ltd., 2015) Bast, Felix
    Monostromataceae have been considered a morphologically discrete group of green algae having thalli made up of a single layer of cells; the family is ubiquitous in intertidal zones of marine and estuarine habitats across the world., However, this view blocks the real complexity of these algae. Using phylogeny reconstruction methods based on five independent molecular data sets (namely, ITS1, ITS2, 5.8S, nrDNA 18S, and rbcL), evolutionary history of this family was inferred for the first time. Results show that monostromatacean algae that have the typical Codiolum-stage sporophyte in the life cycle belong to three clades within Ulotrichales. The present study also suggests that both Ulotrichales and Ulvales are polyphyletic. This report demonstrates for the first time that the 5.8S gene, an often overlooked nucleoribosomal cistron, is a powerful locus for algal phylogeny reconstruction at higher taxonomic levels. ? 2015 ? 2015 Dipartimento di Biologia, Universit? di Firenze.
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    Brown barcoded as red but reality is green! How epiphytic green algae confuse phycologists?
    (Taylor and Francis Ltd., 2015) Bast, Felix; Bhushan, S.; John, A.A.
    Promises and perils of DNA barcoding are now well-known, but no studies have revealed the extent of taxonomic misidentification of algal specimens available in primary DNA sequence repositories. Our original objective was to assess the molecular identity of the ubiquitous brown alga Turbinaria ornata (Sargassaceae:, Fucales) from the southeast Indian coast. We extracted total genomic DNA from freshly collected algal thalli and sequenced the nuclear ribosomal DNA Internal Transcribed Spacer-1 (nrDNA ITS1) barcode locus. Following a BLASTn DNA sequence similarity search, the identity of our alga was Laurencia thyrsifera, a Pacific red alga that has never been reported in India, which came as a big surprise. Further analyses of BLAST hits using a robust phylogenetic framework of Bayesian Inference led to the conclusion that our sequence belonged to an epiphytic Ulvellacean green algal genus Ulvella, which might have been extracted and amplified with our universal ITS primers. This is the first report for Ulvella from India, and detection of this alga growing on Turbinaria. Our Bayesian analyses revealed that a number of GenBank accessions of this epiphyte are misidentified as red algae, which are published in some of the reputed phycological and botanical journals. This finding could have a profound impact on several of the fallacious phylogenetic conclusions arrived at in these publications. ? 2015 Dipartimento di Biologia, Universit? di Firenze.