Department Of Botany

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Author: search.filters.author.Gupta, KritiHas files: No

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    First report of Planomicrobium okeanokoites associated with Himantothallus grandifolius (Desmarestiales, Phaeophyta) from Southern Hemisphere
    (Public Library of Science, 2023-04-14T00:00:00) Chand Saini, Khem; Gupta, Kriti; Sharma, Sheetal; Gautam, Ajay K.; Shamim, Samrin; Mittal, Divya; Kundu, Pushpendu; Bast, Felix
    Gram-positive, aerobic, motile, rod-shaped, mesophilic epiphytic bacterium Planomicrobium okeanokoites was isolated from the surface of endemic species Himantothallus grandifolius in Larsemann Hills, Eastern Antarctica. The diversity of epiphytic bacterial communities living on marine algae remains primarily unexplored; virtually no reports from Antarctic seaweeds. The present study used morpho-molecular approaches for the macroalgae and epiphytic bacterium characterization. Phylogenetic analysis was performed using mitochondrial genome encoded COX1 gene; chloroplast genome encodes rbcL; nuclear genome encoded large subunit ribosomal RNA gene (LSU rRNA) for Himantothallus grandifolius and ribosomal encoded 16S rRNA for Planomicrobium okeanokoites. Morphological and molecular data revealed that the isolate is identified as Himantothallus grandifolius, which belongs to Family Desmarestiaceae of Order Desmarestiales in Class Phaeophyceae showing 99.8% similarity to the sequences of Himantothallus grandifolius, from King George Island, Antarctica (HE866853). The isolated bacterial strain was identified on the basis of chemotaxonomic, morpho-phylogenetic, and biochemical assays. A phylogenetic study based on 16S rRNA gene sequences revealed that the epiphytic bacterial strain SLA-357 was closest related to the Planomicrobium okeanokoites showing 98.7% sequence similarity. The study revealed the first report of this species from the Southern Hemisphere to date. Also, there has been no report regarding the association between the Planomicrobium okeanokoites and Himantothallus grandifolius; however, there are some reports on this bacterium isolated from sediments, soils, and lakes from Northern Hemisphere. This study may open a gateway for further research to know about the mode of interactions and how they affect the physiology and metabolism of each other. � 2023 Saini et al.
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    Abiotic stress in algae: response, signaling and transgenic approaches
    (Springer Science and Business Media B.V., 2022-05-02T00:00:00) Kaur, Manpreet; Saini, Khem Chand; Ojah, Hiramoni; Sahoo, Rajalakshmi; Gupta, Kriti; Kumar, Adesh; Bast, Felix
    High salinity, nutrient deficiency, heavy metals, desiccation, temperature fluctuations, and ultraviolet radiations are major abiotic stress factors considered inhospitable to algal growth and development in natural and artificial environments. All these stressful conditions cause effects on algal physiology and thus biochemical functioning. For instance, long-term exposure to hyper/hypo salinity conditions inhibits cell differentiation and reduces growth. Photosynthesis is completely blocked in algae's dehydrated state, resulting in photoinhibition or photodamage. The limitation of nutrients in aquatic environments inhibits primary production via regulating phytoplankton community development and structure. Hence, in response to these stressful conditions, algae develop plenty of cellular, physiological, and morphological defences to survive and thrive. The conserved and generalized defence responses in algae include the production of secondary metabolites, desaturation of membrane lipids, activation of reactive species scavengers, and accumulation of compatible solutes. Moreover, a well-coordinated and timely response to such stresses involves signal perception and transduction mainly via phytohormones that could sustain algae growth under abiotic stress conditions. In addition, the combination of abiotic stresses and plant hormones could further elevate the biosynthesis of metabolites and enhance the ability of algae to tolerate abiotic stresses. This review aims to present different kinds of stressful conditions confronted by algae and their physiological and biochemical responses, the role of phytohormones in combatting these conditions, and, last, the future transgenic approaches for improving abiotic stress tolerance in algae. � 2022, The Author(s), under exclusive licence to Springer Nature B.V.
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    Arctic biodiversity amidst looming climate apocalypse: Current status and way forward
    (Elsevier, 2021-08-27T00:00:00) Rani, Alka; Gupta, Kriti; Saini, Khem Chand; Narwal, Sahil; Bast, Felix
    Arctic region is at the forefront of climate crisis; this is where the planet is warming maximally and the effects of climate change are most obvious. In this review, we introduce the topic in broader perspective by discussing first on why Arctic biodiversity matters, and scientific evidences for a changing Arctic biodiversity due to climate change. The Arctic then dwells into the current status of Arctic biodiversity covering species diversity and its conservation status with an emphasis on species important for bioprospecting. Subsequently, threats to Arctic biodiversity will be reviewed including climate change, shipping, oil exploration, overfishing, and overharvesting. This essay would then further deliberate why Arctic matters to India in particular. Himadri-Indian research station at Svalbard, Norway-will be briefed followed by an overview of Svalbard Global Seed Vault and why signing a pact with this international facility would benefit the country. The essay concludes with final thoughts and way forward including strategies to minimize Arctic biodiversity loss, UN SDGs (Ssustainable Ddevelopment Ggoals), and climate action. � 2021 Elsevier Inc. All rights reserved.
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    Morphophylogenetic assessment of a new moss species Bryum bharatiense sp. nov. (Bryaceae) from Larsemann Hills, Eastern Antarctica
    (National Science Museum od Korea, 2021-07-16T00:00:00) Rehman, Wahid Ul; Gupta, Kriti; Bast, Felix
    Bryum is recognized as a cosmopolitan genus of mosses in the family Bryaceae that contains the largest diversity of mosses. Although there are around 100 species of moss species reported from Antarctica to date, the actual species diversity remains elusive, as the continent remains one of the least explored habitats globally. Here, we describe a new species of Bryum from the Larsemann Hills, Eastern Antarctica, with several synapomorphic characters, including unbranched plant body, ovate-lanceolate leaves, reflexed leaf margins with slightly serrulate apex, and percurrent coasta. In nuclear ribosomal DNA internal transcribed spacer 1 phylogram, our isolate did not cluster with any known species of this genus. The closest BLASTn hit was found to be Bryum pseudotriquetrum, but our isolate had several distinct synapomorphic traits. Based on morphological and molecular data, a new moss species, Bryum bharatiense sp. nov. is formally proposed herein. Besides, two new taxonomic records are also presented in this study, viz. Bryoerythrophyllum recurvirostrum from Larsemann Hills and Coscinodon lawianus from Schirmacher Oasis. � 2021 National Science Museum of Korea (NSMK) and Korea National Arboretum (KNA)
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    First report of Planomicrobium okeanokoites associated with Himantothallus grandifolius (Desmarestiales, Phaeophyta) from Southern Hemisphere
    (Public Library of Science, 2023-04-14T00:00:00) Chand Saini, Khem; Gupta, Kriti; Sharma, Sheetal; Gautam, Ajay K.; Shamim, Samrin; Mittal, Divya; Kundu, Pushpendu; Bast, Felix
    Gram-positive, aerobic, motile, rod-shaped, mesophilic epiphytic bacterium Planomicrobium okeanokoites was isolated from the surface of endemic species Himantothallus grandifolius in Larsemann Hills, Eastern Antarctica. The diversity of epiphytic bacterial communities living on marine algae remains primarily unexplored; virtually no reports from Antarctic seaweeds. The present study used morpho-molecular approaches for the macroalgae and epiphytic bacterium characterization. Phylogenetic analysis was performed using mitochondrial genome encoded COX1 gene; chloroplast genome encodes rbcL; nuclear genome encoded large subunit ribosomal RNA gene (LSU rRNA) for Himantothallus grandifolius and ribosomal encoded 16S rRNA for Planomicrobium okeanokoites. Morphological and molecular data revealed that the isolate is identified as Himantothallus grandifolius, which belongs to Family Desmarestiaceae of Order Desmarestiales in Class Phaeophyceae showing 99.8% similarity to the sequences of Himantothallus grandifolius, from King George Island, Antarctica (HE866853). The isolated bacterial strain was identified on the basis of chemotaxonomic, morpho-phylogenetic, and biochemical assays. A phylogenetic study based on 16S rRNA gene sequences revealed that the epiphytic bacterial strain SLA-357 was closest related to the Planomicrobium okeanokoites showing 98.7% sequence similarity. The study revealed the first report of this species from the Southern Hemisphere to date. Also, there has been no report regarding the association between the Planomicrobium okeanokoites and Himantothallus grandifolius; however, there are some reports on this bacterium isolated from sediments, soils, and lakes from Northern Hemisphere. This study may open a gateway for further research to know about the mode of interactions and how they affect the physiology and metabolism of each other. � 2023 Saini et al.
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    Abiotic stress in algae: response, signaling and transgenic approaches
    (Springer Science and Business Media B.V., 2022-05-02T00:00:00) Kaur, Manpreet; Saini, Khem Chand; Ojah, Hiramoni; Sahoo, Rajalakshmi; Gupta, Kriti; Kumar, Adesh; Bast, Felix
    High salinity, nutrient deficiency, heavy metals, desiccation, temperature fluctuations, and ultraviolet radiations are major abiotic stress factors considered inhospitable to algal growth and development in natural and artificial environments. All these stressful conditions cause effects on algal physiology and thus biochemical functioning. For instance, long-term exposure to hyper/hypo salinity conditions inhibits cell differentiation and reduces growth. Photosynthesis is completely blocked in algae's dehydrated state, resulting in photoinhibition or photodamage. The limitation of nutrients in aquatic environments inhibits primary production via regulating phytoplankton community development and structure. Hence, in response to these stressful conditions, algae develop plenty of cellular, physiological, and morphological defences to survive and thrive. The conserved and generalized defence responses in algae include the production of secondary metabolites, desaturation of membrane lipids, activation of reactive species scavengers, and accumulation of compatible solutes. Moreover, a well-coordinated and timely response to such stresses involves signal perception and transduction mainly via phytohormones that could sustain algae growth under abiotic stress conditions. In addition, the combination of abiotic stresses and plant hormones could further elevate the biosynthesis of metabolites and enhance the ability of algae to tolerate abiotic stresses. This review aims to present different kinds of stressful conditions confronted by algae and their physiological and biochemical responses, the role of phytohormones in combatting these conditions, and, last, the future transgenic approaches for improving abiotic stress tolerance in algae. � 2022, The Author(s), under exclusive licence to Springer Nature B.V.
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    Arctic biodiversity amidst looming climate apocalypse: Current status and way forward
    (Elsevier, 2021-08-27T00:00:00) Rani, Alka; Gupta, Kriti; Saini, Khem Chand; Narwal, Sahil; Bast, Felix
    Arctic region is at the forefront of climate crisis; this is where the planet is warming maximally and the effects of climate change are most obvious. In this review, we introduce the topic in broader perspective by discussing first on why Arctic biodiversity matters, and scientific evidences for a changing Arctic biodiversity due to climate change. The Arctic then dwells into the current status of Arctic biodiversity covering species diversity and its conservation status with an emphasis on species important for bioprospecting. Subsequently, threats to Arctic biodiversity will be reviewed including climate change, shipping, oil exploration, overfishing, and overharvesting. This essay would then further deliberate why Arctic matters to India in particular. Himadri-Indian research station at Svalbard, Norway-will be briefed followed by an overview of Svalbard Global Seed Vault and why signing a pact with this international facility would benefit the country. The essay concludes with final thoughts and way forward including strategies to minimize Arctic biodiversity loss, UN SDGs (Ssustainable Ddevelopment Ggoals), and climate action. � 2021 Elsevier Inc. All rights reserved.
  • No Thumbnail Available
    Item
    Morphophylogenetic assessment of a new moss species Bryum bharatiense sp. nov. (Bryaceae) from Larsemann Hills, Eastern Antarctica
    (National Science Museum od Korea, 2021-07-16T00:00:00) Rehman, Wahid Ul; Gupta, Kriti; Bast, Felix
    Bryum is recognized as a cosmopolitan genus of mosses in the family Bryaceae that contains the largest diversity of mosses. Although there are around 100 species of moss species reported from Antarctica to date, the actual species diversity remains elusive, as the continent remains one of the least explored habitats globally. Here, we describe a new species of Bryum from the Larsemann Hills, Eastern Antarctica, with several synapomorphic characters, including unbranched plant body, ovate-lanceolate leaves, reflexed leaf margins with slightly serrulate apex, and percurrent coasta. In nuclear ribosomal DNA internal transcribed spacer 1 phylogram, our isolate did not cluster with any known species of this genus. The closest BLASTn hit was found to be Bryum pseudotriquetrum, but our isolate had several distinct synapomorphic traits. Based on morphological and molecular data, a new moss species, Bryum bharatiense sp. nov. is formally proposed herein. Besides, two new taxonomic records are also presented in this study, viz. Bryoerythrophyllum recurvirostrum from Larsemann Hills and Coscinodon lawianus from Schirmacher Oasis. � 2021 National Science Museum of Korea (NSMK) and Korea National Arboretum (KNA)