An alternative in vitro propagation protocol for shoot differentiation from callus culture has be... more An alternative in vitro propagation protocol for shoot differentiation from callus culture has been developed for Hippophae rhamnoides using hypocotyle part of in vitro germinated seedlings. Massive callus was obtained in WP medium containing 5.0 μm BA. Subsequently callus was transferred to WP medium containing various concentrations and combinations of BA and GA 3 for shoot differentiation. The combination of BA (5.0 μM) and GA 3 (1.0 μM) resulted in maximum response in terms of shoot differentiation i.e., 8 shoots per callus lump after 28 days of culture. However, lower concentration of BA (0.5 μM) in the same medium resulted in better growth of shoots. Maximum rooting (78.0%) was obtained within 30 days when micro shoots (2-3cm) were cultured in WP medium with 0.5 μM NAA. The rooted plantlets were successfully transferred to soil mix (soil and farmyard manure, 3: 1) and hardened in nursery under shadehouse conditions. Abbreviations: BA: 6-benzyladenine; GA 3 : Gibberellic acid; ...
The Journal of Horticultural Science and Biotechnology, 2010
Summary We have developed a two-step procedure for rooting of tea microshoots in vitro. The effec... more Summary We have developed a two-step procedure for rooting of tea microshoots in vitro. The effectiveness of different auxin treatments for root formation was found to differ. Among the auxins tested, 25 μM -naphthalene acetic acid (NAA) gave the best results, with 100% rooting, compared to 25 μM indole-3-butyric acid (IBA) or 25 μM indole-3-acetic acid (IAA), which induced 17% and 58% rooting, respectively. Incubation of tea microshoots on 0.33 Murashige and Skoog (MS) medium, supplemented with 25.0 μM NAA or 175.0 μM IBA for 10 d, followed by transfer to auxin-free 0.33 MS medium resulted in 100% rooting, whereas 50.0 μM IAA induced 91.7% rooting. Besides the different auxin treatments, the strength of the MS medium, the duration of incubation of microshoots in auxin-containing medium, the sucrose concentration, the gelling agent, the pH of the medium, the incubation temperature, the light intensity, and the quality of the shoots also played a significant role during in vitro rooting of micropropagated tea shoots. Among the combinations tested, the most effective results were obtained when green microshoots were incubated on 0.33 MS medium supplemented with 25.0 μM NAA, 50.0 mM sucrose, pH 5.5, gelled with 0.2% (w/v) PhytagelTM for 10 d at 25° – 30°C at a light intensity of 40 μmol m–2 s–1, followed by transfer of shoots to auxin-free 0.3 MS medium. This resulted in 100% rooting and, on average, 11 long roots were formed per shoot. Anatomical changes during adventitious rooting of micropropagated tea shoots in vitro were also studied to understand the process of rooting.
... Niladri Bag, Anil Kumar, Shyamal K. Nandi, Anita Pandey and Lok Man S. Palni ... A two step I... more ... Niladri Bag, Anil Kumar, Shyamal K. Nandi, Anita Pandey and Lok Man S. Palni ... A two step Inethod has been developed (culture of microshoots in % MS medium containing 25.0 JlM NAA or 175.0 JlM IBA for 10 days, followed by transfer to plant growth regulator (PGR)-free ...
Cancer Epidemiology, Biomarkers & Prevention, 2008
In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive o... more In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive oxygen species generated by mitochondrial respiratory chain. Mitochondrial superoxide dismutase [SOD; manganese SOD (MnSOD) or SOD2] neutralizes highly reactive superoxide radical (O•-2), the first member in the plethora of mitochondrial reactive oxygen species. A polymorphism in the target sequence of MnSOD enzyme, Val16Ala, is known to disrupt proper targeting of the enzyme from cytosol to mitochondrial matrix where it acts on O•-2 to dismutate it to hydrogen peroxide (H2O2). A change in the level of O•-2 and of H2O2 in mitochondria modulates the molecular mechanisms of apoptosis, cellular adhesion, and cell proliferation and thus play key role in cancer development. Previous studies investigating the association between MnSOD Val16Ala polymorphism and cancer risk have revealed inconsistent results. We conducted a meta-analysis on these studies. Our meta-analysis on total of 7,366 cance...
In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive o... more In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive oxygen species generated by mitochondrial respiratory chain. Mitochondrial superoxide dismutase [SOD; manganese SOD (MnSOD) or SOD2] neutralizes highly reactive superoxide radical (O.-2), the first member in the plethora of mitochondrial reactive oxygen species. A polymorphism in the target sequence of MnSOD enzyme, Val16Ala, is known to disrupt proper targeting of the enzyme from cytosol to mitochondrial matrix where it acts on O.-2 to dismutate it to hydrogen peroxide (H2O2). A change in the level of O. 2 and of H2O2 in mitochondria modulates the molecular mechanisms of
Thamnocalamus spathiflorus (Trin.) Munro an evergreen, temperate bamboo is important in the Himal... more Thamnocalamus spathiflorus (Trin.) Munro an evergreen, temperate bamboo is important in the Himalayan context. In this study seed storage, effect of temperature, GA3 and seven different type of lights were used for enhancing/uniform seed germination of this bamboo species. Sun- dried seeds were stored at room temperature (20-25°C) for four years and viability was 90-93% for the entire period. 25°C was found to be the best temperature in which after 3 days of sowing seed germination was started and 93.3% germination was recorded 12 days after sowing. Treatment of GA3 (250-5000 μM) was significant under the limitation of this experiment. Among the seven types of light treatments yellow light treatment gave the best performance with 43.3% germination at day three, 73.3% at day 5 and 100% by day 10. Red light was found to be the least effective and maximum 76.7% seeds were germinated with this treatment.
The application of tissue culture techniques for rapid and clonal mass propagation and improvemen... more The application of tissue culture techniques for rapid and clonal mass propagation and improvement of tea is well known. While several laboratories have successfully developed in vitro propagation protocols, the use of this technology for mass multiplication of tea at commercial level is still limited largely due to difficulty in the quality of rooting of microshoots, and problems associated with subsequent hardening and field establishment. The present study reports a reproducible protocol for 100% rooting of in vitro propagated tea microshoots using a two-step method. This involves culture of microshoots on IBA (indole-3-butyric acid; 175.0 pM) containing Murashige and Skoog (1962; MS) medium for 10 days followed by transfer to 113 strength MS medium without any plant growth regulator. Besides the concentration of IBA, the period of exposure of microshoots to IBA containing medium (prior to transfer to PGR-free medium) also played a significant role in rooting. In addition, the cu...
The rooting ability of air layered shoots of Myrica esculenta Buch. - Ham. ex D. Don, a commercia... more The rooting ability of air layered shoots of Myrica esculenta Buch. - Ham. ex D. Don, a commercially important and difficult to root species, has been examined using different chemicals. Various concentrations (100, 500 &1000 ppm) of auxins (IBA and NAA), and a systemic fungicide Bavistin (containing 50% Carbendazim) were applied using a soil paste to the shoots during the rainy season. The lower concentrations of IBA (100 & 500 ppm) only resulted in rooting (20.0 & 53.33% respectively, compared to no rooting in control shoots); the highest number of roots per air layered shoot was formed when 500 ppm IBA was applied. Clonal plants raised through this method have been successfully established in earthen pots.
Niladri Bag*, Lok Man S. Palni, Suman Chandra and Shyamal K. Nandi G.B. Pant Institute of Himalay... more Niladri Bag*, Lok Man S. Palni, Suman Chandra and Shyamal K. Nandi G.B. Pant Institute of Himalayan Environment and Development, Kosi-Katarmal, Almora 263 643, India Present address: Sikkim University, Department of Plantation Management and Studies, 6th Mile, Samdur, P.O. Tadong, Gangtok 737 102, India Present address: National Center for Natural Products Research, Research School of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS 38677, USA
Large cardamom (Amomum subulatum Roxb.) is now affected by several diseases caused by both viruse... more Large cardamom (Amomum subulatum Roxb.) is now affected by several diseases caused by both viruses and fungi. At present, leaf blight is considered a major threat to cardamom cultivation in Sikkim. During the past two decades, cultivation of the crop in this region has dropped by almost 60%. Hence, to quantify the severity of leaf blight damage and identification of the causal organism for the disease, a survey was conducted from May to August 2017 in different large cardamom growing regions of Sikkim. During this survey, a typical symptom of leaf blight was observed on cardamom leaves in many locations. The leaves with blights were collected, surface sterilized, and inoculated on potato dextrose agar (PDA). The pathogen was isolated as pure culture, and on the basis of morphological and microscopic characteristics, the fungus was identified species of Curvularia. Molecular characterization of the fungal isolate with ITS-rDNA partial gene amplification using universal primers (ITS4 and ITS5), showed 100% similarity with Curvularia eragrostidis (family: Pleosporaceae). The fungal isolate and nucleotide sequence was deposited in National Fungal Culture Collection of India (NFCCI), Pune and NCBI with accession numbers NFCCI 4541 and MN710527, respectively. This is the first report on the occurrence of C. eragrostidis pathogen causing leaf blight of large cardamom grown in Sikkim.
Tea polyphenols are secondary metabolites of tea plants and are well known for beneficial health ... more Tea polyphenols are secondary metabolites of tea plants and are well known for beneficial health effects. They can protect from a variety of illnesses including cancers. Tea polyphenols can prevent cancer by modulating epigenetic aberrations taking place in DNA methylation, histone modifications, and micro-RNAs. By altering these epimutations, they regulate chromatin dynamics and expression of genes those induce or suppress cancer formation. However, majority of the studies in existing literature are carried out for green tea polyphenols rather than black tea polyphenols despite the fact that black tea is the most commonly consumed form of tea (78%) followed by green tea (20%) and other forms of tea. Research findings indicate that tea polyphenols may be potential source from which drugs with less side effects and affordable price can be developed.
An alternative in vitro propagation protocol for shoot differentiation from callus culture has be... more An alternative in vitro propagation protocol for shoot differentiation from callus culture has been developed for Hippophae rhamnoides using hypocotyle part of in vitro germinated seedlings. Massive callus was obtained in WP medium containing 5.0 μm BA. Subsequently callus was transferred to WP medium containing various concentrations and combinations of BA and GA 3 for shoot differentiation. The combination of BA (5.0 μM) and GA 3 (1.0 μM) resulted in maximum response in terms of shoot differentiation i.e., 8 shoots per callus lump after 28 days of culture. However, lower concentration of BA (0.5 μM) in the same medium resulted in better growth of shoots. Maximum rooting (78.0%) was obtained within 30 days when micro shoots (2-3cm) were cultured in WP medium with 0.5 μM NAA. The rooted plantlets were successfully transferred to soil mix (soil and farmyard manure, 3: 1) and hardened in nursery under shadehouse conditions. Abbreviations: BA: 6-benzyladenine; GA 3 : Gibberellic acid; ...
The Journal of Horticultural Science and Biotechnology, 2010
Summary We have developed a two-step procedure for rooting of tea microshoots in vitro. The effec... more Summary We have developed a two-step procedure for rooting of tea microshoots in vitro. The effectiveness of different auxin treatments for root formation was found to differ. Among the auxins tested, 25 μM -naphthalene acetic acid (NAA) gave the best results, with 100% rooting, compared to 25 μM indole-3-butyric acid (IBA) or 25 μM indole-3-acetic acid (IAA), which induced 17% and 58% rooting, respectively. Incubation of tea microshoots on 0.33 Murashige and Skoog (MS) medium, supplemented with 25.0 μM NAA or 175.0 μM IBA for 10 d, followed by transfer to auxin-free 0.33 MS medium resulted in 100% rooting, whereas 50.0 μM IAA induced 91.7% rooting. Besides the different auxin treatments, the strength of the MS medium, the duration of incubation of microshoots in auxin-containing medium, the sucrose concentration, the gelling agent, the pH of the medium, the incubation temperature, the light intensity, and the quality of the shoots also played a significant role during in vitro rooting of micropropagated tea shoots. Among the combinations tested, the most effective results were obtained when green microshoots were incubated on 0.33 MS medium supplemented with 25.0 μM NAA, 50.0 mM sucrose, pH 5.5, gelled with 0.2% (w/v) PhytagelTM for 10 d at 25° – 30°C at a light intensity of 40 μmol m–2 s–1, followed by transfer of shoots to auxin-free 0.3 MS medium. This resulted in 100% rooting and, on average, 11 long roots were formed per shoot. Anatomical changes during adventitious rooting of micropropagated tea shoots in vitro were also studied to understand the process of rooting.
... Niladri Bag, Anil Kumar, Shyamal K. Nandi, Anita Pandey and Lok Man S. Palni ... A two step I... more ... Niladri Bag, Anil Kumar, Shyamal K. Nandi, Anita Pandey and Lok Man S. Palni ... A two step Inethod has been developed (culture of microshoots in % MS medium containing 25.0 JlM NAA or 175.0 JlM IBA for 10 days, followed by transfer to plant growth regulator (PGR)-free ...
Cancer Epidemiology, Biomarkers & Prevention, 2008
In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive o... more In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive oxygen species generated by mitochondrial respiratory chain. Mitochondrial superoxide dismutase [SOD; manganese SOD (MnSOD) or SOD2] neutralizes highly reactive superoxide radical (O•-2), the first member in the plethora of mitochondrial reactive oxygen species. A polymorphism in the target sequence of MnSOD enzyme, Val16Ala, is known to disrupt proper targeting of the enzyme from cytosol to mitochondrial matrix where it acts on O•-2 to dismutate it to hydrogen peroxide (H2O2). A change in the level of O•-2 and of H2O2 in mitochondria modulates the molecular mechanisms of apoptosis, cellular adhesion, and cell proliferation and thus play key role in cancer development. Previous studies investigating the association between MnSOD Val16Ala polymorphism and cancer risk have revealed inconsistent results. We conducted a meta-analysis on these studies. Our meta-analysis on total of 7,366 cance...
In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive o... more In normal state of a cell, endogenous antioxidant enzyme system maintains the level of reactive oxygen species generated by mitochondrial respiratory chain. Mitochondrial superoxide dismutase [SOD; manganese SOD (MnSOD) or SOD2] neutralizes highly reactive superoxide radical (O.-2), the first member in the plethora of mitochondrial reactive oxygen species. A polymorphism in the target sequence of MnSOD enzyme, Val16Ala, is known to disrupt proper targeting of the enzyme from cytosol to mitochondrial matrix where it acts on O.-2 to dismutate it to hydrogen peroxide (H2O2). A change in the level of O. 2 and of H2O2 in mitochondria modulates the molecular mechanisms of
Thamnocalamus spathiflorus (Trin.) Munro an evergreen, temperate bamboo is important in the Himal... more Thamnocalamus spathiflorus (Trin.) Munro an evergreen, temperate bamboo is important in the Himalayan context. In this study seed storage, effect of temperature, GA3 and seven different type of lights were used for enhancing/uniform seed germination of this bamboo species. Sun- dried seeds were stored at room temperature (20-25°C) for four years and viability was 90-93% for the entire period. 25°C was found to be the best temperature in which after 3 days of sowing seed germination was started and 93.3% germination was recorded 12 days after sowing. Treatment of GA3 (250-5000 μM) was significant under the limitation of this experiment. Among the seven types of light treatments yellow light treatment gave the best performance with 43.3% germination at day three, 73.3% at day 5 and 100% by day 10. Red light was found to be the least effective and maximum 76.7% seeds were germinated with this treatment.
The application of tissue culture techniques for rapid and clonal mass propagation and improvemen... more The application of tissue culture techniques for rapid and clonal mass propagation and improvement of tea is well known. While several laboratories have successfully developed in vitro propagation protocols, the use of this technology for mass multiplication of tea at commercial level is still limited largely due to difficulty in the quality of rooting of microshoots, and problems associated with subsequent hardening and field establishment. The present study reports a reproducible protocol for 100% rooting of in vitro propagated tea microshoots using a two-step method. This involves culture of microshoots on IBA (indole-3-butyric acid; 175.0 pM) containing Murashige and Skoog (1962; MS) medium for 10 days followed by transfer to 113 strength MS medium without any plant growth regulator. Besides the concentration of IBA, the period of exposure of microshoots to IBA containing medium (prior to transfer to PGR-free medium) also played a significant role in rooting. In addition, the cu...
The rooting ability of air layered shoots of Myrica esculenta Buch. - Ham. ex D. Don, a commercia... more The rooting ability of air layered shoots of Myrica esculenta Buch. - Ham. ex D. Don, a commercially important and difficult to root species, has been examined using different chemicals. Various concentrations (100, 500 &1000 ppm) of auxins (IBA and NAA), and a systemic fungicide Bavistin (containing 50% Carbendazim) were applied using a soil paste to the shoots during the rainy season. The lower concentrations of IBA (100 & 500 ppm) only resulted in rooting (20.0 & 53.33% respectively, compared to no rooting in control shoots); the highest number of roots per air layered shoot was formed when 500 ppm IBA was applied. Clonal plants raised through this method have been successfully established in earthen pots.
Niladri Bag*, Lok Man S. Palni, Suman Chandra and Shyamal K. Nandi G.B. Pant Institute of Himalay... more Niladri Bag*, Lok Man S. Palni, Suman Chandra and Shyamal K. Nandi G.B. Pant Institute of Himalayan Environment and Development, Kosi-Katarmal, Almora 263 643, India Present address: Sikkim University, Department of Plantation Management and Studies, 6th Mile, Samdur, P.O. Tadong, Gangtok 737 102, India Present address: National Center for Natural Products Research, Research School of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS 38677, USA
Large cardamom (Amomum subulatum Roxb.) is now affected by several diseases caused by both viruse... more Large cardamom (Amomum subulatum Roxb.) is now affected by several diseases caused by both viruses and fungi. At present, leaf blight is considered a major threat to cardamom cultivation in Sikkim. During the past two decades, cultivation of the crop in this region has dropped by almost 60%. Hence, to quantify the severity of leaf blight damage and identification of the causal organism for the disease, a survey was conducted from May to August 2017 in different large cardamom growing regions of Sikkim. During this survey, a typical symptom of leaf blight was observed on cardamom leaves in many locations. The leaves with blights were collected, surface sterilized, and inoculated on potato dextrose agar (PDA). The pathogen was isolated as pure culture, and on the basis of morphological and microscopic characteristics, the fungus was identified species of Curvularia. Molecular characterization of the fungal isolate with ITS-rDNA partial gene amplification using universal primers (ITS4 and ITS5), showed 100% similarity with Curvularia eragrostidis (family: Pleosporaceae). The fungal isolate and nucleotide sequence was deposited in National Fungal Culture Collection of India (NFCCI), Pune and NCBI with accession numbers NFCCI 4541 and MN710527, respectively. This is the first report on the occurrence of C. eragrostidis pathogen causing leaf blight of large cardamom grown in Sikkim.
Tea polyphenols are secondary metabolites of tea plants and are well known for beneficial health ... more Tea polyphenols are secondary metabolites of tea plants and are well known for beneficial health effects. They can protect from a variety of illnesses including cancers. Tea polyphenols can prevent cancer by modulating epigenetic aberrations taking place in DNA methylation, histone modifications, and micro-RNAs. By altering these epimutations, they regulate chromatin dynamics and expression of genes those induce or suppress cancer formation. However, majority of the studies in existing literature are carried out for green tea polyphenols rather than black tea polyphenols despite the fact that black tea is the most commonly consumed form of tea (78%) followed by green tea (20%) and other forms of tea. Research findings indicate that tea polyphenols may be potential source from which drugs with less side effects and affordable price can be developed.
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