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PublicationArticle Silicon nanoparticles more efficiently alleviate arsenate toxicity than silicon in maize cultiver and hybrid differing in arsenate tolerance(Frontiers Media S.A., 2016) Durgesh Kumar Tripathi; Swati Singh; Vijay Pratap Singh; Sheo Mohan Prasad; Devendra Kumar Chauhan; Nawal Kishore DubeyAlleviation of abiotic stress by silicon (Si) is well documented. But mitigation of abiotic stress by silicon nanoparticles (SiNPs) is not much known. Therefore, hydroponic experiments were conducted to investigate if SiNPs are more effective than Si in mitigation of arsenate (As V ; 25 and 50 μM) toxicity in maize cultivar and hybrid differing in As V tolerance. Under As V stress, reduction in growth was accompanied by enhanced level of As and oxidative stress. As V inhibited activities of antioxidant enzymes like ascorbate peroxidase, glutathione reductase, and dehydroascorbate reductase (except superoxide dismutase). The redox status of ascorbate and glutathione was disturbed by As V as indicated by a steep decline in their reduced/oxidized ratios. However, addition of Si and SiNp ameliorates As V toxicity in maize. Si and SiNp both could reduce As V toxicity in maize cultivar and hybrid, which could be related with decreased accumulation of As and oxidative stress, and enhanced components of the ascorbate-glutathione cycle (AsA-GSH cycle). But lowering in the accumulation of As and oxidative stress markers, and enhancement in components of the AsA-GSH cycle was prominent in SiNp fed seedlings under As V stress. The results also showed that SiNp are more effective in reducing AsV toxicity than Si, which is due to their greater availability to seedlings. Comparing responses of cultivar and hybrid, maize cultivar shows more resistance against As V than hybrid. © 2016 Tripathi, Singh, Singh, Prasad, Chauhan and Dubey.PublicationBook Nanomaterials in Plants, Algae, and Microorganisms(Elsevier Inc., 2017) Durgesh Kumar Tripathi; Parvaiz Ahmad; Shivesh Sharma; Devendra Kumar Chauhan; Nawal Kishore DubeyNanomaterials in Plants, Algae and Microorganisms: Concepts and Controversies: Volume One discusses the vast amount of nanomaterials that have been released into the environment in a relatively short amount of time. There is a need to understand what the implications to the health of our biota and ecosystems are as the earth is increasingly inundated with these materials. Not all of the effects are negative, but their impacts are increasing exponentially due to their size, quantity and other factors. © 2018 Elsevier Inc. All rights reserved.PublicationRetracted The interplay between reactive oxygen and nitrogen species contributes in the regulatory mechanism of the nitro-oxidative stress induced by cadmium in Arabidopsis(Elsevier B.V., 2018) Shiliang Liu; Rongjie Yang; Durgesh Kumar Tripathi; Xi Li; Wei He; Mengxi Wu; Shafaqat Ali; Mingdong Ma; Qingsu Cheng; Yuanzhi PanNitric oxide ([rad]NO) involved in various metabolic processes in plants. Although its significant influence has been established, the exact mechanisms of [rad]NO-derived products under metal-stress conditions are largely unknown. Here, we investigated the key components of reactive oxygen/nitrogen species (ROS/RNS) metabolisms under cadmium (Cd) stress using Arabidopsis as the model plant. Exposure to Cd disturbed redox homeostasis and increased lipid peroxidation, thus triggering oxidative stress. Complementarily, Cd caused differential changes in the selected amino acids: a promotion in partial amino acids might be a genotype-specific trait, while the phenylalanine ammonia-lyase activity increased in a dose-dependent manner in shoots. Furthermore, [rad]NO production as well as S-nitrosoglutathione (GSNO) reductase (GSNOR) activity were up-regulated by Cd with the simultaneous depletion of GSNO. Correspondingly, S-nitrosothiols were involved in generating peroxynitrite and tyrosine nitration of protein (NO2-Tyr), in accordance with the regulation of [rad]NO-mediated post-translational modifications in antioxidant systems, including the ascorbate-glutathione cycle, amino acids and phenolic compounds, thereby provoking nitrosative stress. Our data provide comprehensive evidences regarding the clear relationships between the metabolisms of ROS and RNS, supporting the indicator role of NO2-Tyr as a nitrosative stress in plants, and help to provide a better understanding of the ROS/RNS interaction under stress conditions. © 2017 Elsevier B.V.PublicationArticle Morpho-anatomical and biochemical adapting strategies of maize (Zea mays L.) seedlings against lead and chromium stresses(Elsevier Ltd, 2015) Swati Singh; Prabhat Kumar Srivastava; Dharmendra Kumar; Durgesh Kumar Tripathi; Devendra Kumar Chauhan; Sheo Mohan PrasadThis study was aimed to investigate an impact of different concentrations of lead (Pb: 50-300μM) and chromium (Cr: 50-300μM) on maize seedlings (Zea mays L.). Results revealed that Pb and Cr at their 300μM concentrations showed significant (P<0.05) reduction in growth, photosynthetic pigments, protein and mineral contents (except S), which were accompanied by a significant increase in the accumulation of Pb and Cr, lipid peroxidation (measured as malondialdehyde; MDA) and hydrogen peroxide (H2O2). Mineral distribution and anatomical traits were also severely affected at 300μM of Pb and Cr concentration. Moreover, in comparison to Pb, different Cr treatments up to 200μM showed severe toxicity responses and significantly hampered the growth, photosynthetic pigments, minerals (except S) and anatomical features of the maize seedlings due to an increase in the accumulation of Cr in tissues and oxidative stress.Shoot and root anatomy of maize seedlings was severely affected up to 200. μM concentration of Cr while Pb showed trivial impact on anatomical features. Interestingly, the thickness of leaf midrib increased which could be correlated with the increased level of Pb and Cr in the cell wall, representing an approach to avoid their translocation to photosynthetic tissues. Epiblema and endodermis of the root were thickened while cortical cells were degraded. An increase in the number of protoxylem, perhaps had increased the availability of water in roots under different concentrations of Pb and Cr which could have protected the plants under the stress conditions. © 2015 Elsevier Ltd.PublicationArticle A potential contribution of achene micromorphology and phytolith analysis in describing the systematics of genus Bolboschoenus from India(Springer-Verlag Wien, 2015) Sanjay Mishra; Durgesh Kumar Tripathi; Zdenka Hroudová; Devendra Kumar ChauhanThree entities of taxonomically difficult genus Bolboschoenus collected from India were subjected to micromorphological and phytolith studies. For micromorphological study, silica bodies in the outer cells of the achene epidermis were revealed by acetolysis and sonication and examined by scanning electron microscopy. A silica body consists of a basal platform, one or more large elevated protuberances, and sometimes smaller satellite protuberances. Significant differences have been found in the number of protuberances, the presence/absence of satellites, the texture of the platform, and the occurrence of nodules on the larger protuberances at individual species level. These features, combined with achene shape and characteristics of the anticlinal walls of the epidermal cells (undulate vs. straight, thick vs. thin, buttressed or not), are expressed in a unique combination for each entity. It is clearly evident from the study that micromorphological characters of the achene epidermis vary significantly between different species. Therefore, the micromorphology of the achene epidermis of Bolboschoenus is valuable in understanding the taxonomy at infraspecific, specific and supraspecific levels in the genus. Results provided by phytolith analysis are useful not only in taxonomic demarcation of Bolboschoenus, but they will be useful in future archaeobotanical and paleoecological investigations also. In conclusion, present study confirms the presence of B. affinis and B. glaucus in India, while suggests more investigation on presence of B. maritimus in India. © 2014, Springer-Verlag Wien.PublicationArticle Interactive Effect of Silicon (Si) and Salicylic Acid (SA) in Maize Seedlings and Their Mechanisms of Cadmium (Cd) Toxicity Alleviation(Springer New York LLC, 2019) Swati Singh; Vijay Pratap Singh; Sheo Mohan Prasad; Shivesh Sharma; Naleeni Ramawat; Nawal Kishore Dubey; Durgesh Kumar Tripathi; Devendra Kumar ChauhanThe present study has been conducted to evaluate the impact of silicon (Si) and salicylic acid (SA) in the regulation of Cd-induced toxicity in maize seedlings. Cadmium (Cd: 100 µM) significantly reduced root and shoot fresh weight and length, photosynthetic pigments, total soluble protein content and chlorophyll fluorescence parameters. Cadmium decreased root and shoot length by 23 and 19% and fresh weight by 27 and 24%, respectively when compared to their respective controls. Similarly, total chlorophyll, carotenoids and total soluble protein were decreased by 21, 18 and 28%, respectively by Cd. In contrast, the addition of SA (500 µM) and Si (10 µM), and their combination (SA + Si) together with Cd treatment successfully ameliorated Cd-induced harmful impacts on studied parameters as SA and Si alone and in combination reduced Cd accumulation and oxidative stresses and thus refurbish the damages. Cd significantly stimulated activity of superoxide dismutase while inhibited activities of ascorbate peroxidase (APX), glutathione reductase (GR) and dehydroascorbate reductase (DHAR), and declined total ascorbate and glutathione contents. In contrast, the addition of SA and Si alone and in combination stimulated the activities of APX, GR and DHAR and significantly increased levels of total ascorbate and glutathione. In conclusion, the present study suggested that although SA and Si both alone are able to alleviate Cd-induced toxicity in maize seedlings, but their combination was the most effective in nullifying Cd-induced toxicity in maize seedlings. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.PublicationBook Chapter Preface(wiley, 2020) Prabhat Kumar Srivastava; Vijay Pratap Singh; Anita Singh; Durgesh Kumar Tripathi; Samiksha Singh; Sheo Mohan Prasad; Devendra Kumar Chauhan[No abstract available]PublicationArticle Silicon bioavailability in exocarp of Cucumis sativus Linn(Springer Verlag, 2017) Deepika Tripathi; Mrigank Mauli Dwivedi; Durgesh Kumar Tripathi; Devendra Kumar ChauhanScanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA) techniques have been used to detect the silicon bioavailability in the exocarp of warty cucumber surface. Warts appear at the time of anthesis and are remnant part of spines/trichomes which on further fruit maturation abscised from the exocarp. Results of EPMA and phytolith analysis clearly revealed that the surface of exocarp (fruit) of Cucumis sativus Linn. containing warts has greater quantity of silicon as compared to the other part of the fruit. Besides silicon, some other elements were also found, on the fruit exocarp and its surrounding area. The other elements are magnesium (Mg), aluminum (Al), phosphorus (P), sulfur (S), potassium (K), calcium (Ca), iron (Fe), nickel (Ni), copper (Cu), and sodium. The percentage of silica is highest followed by Ni, Ca, Al, P, Mg, Fe, S, Cu, K, and Cl. Thus, this study clearly demonstrates that Cucumis sativus Linn. fruits which are used as salads and appetizers on daily basis are loaded with silicon and other useful elements and possess numerous health benefits. © 2017, Springer-Verlag GmbH Germany.PublicationArticle Effect of Arsenic on Growth, Arsenic Uptake, Distribution of Nutrient Elements and Thiols in Seedlings of Wrightia arborea (Dennst.) Mabb(Taylor and Francis Inc., 2015) Dharmendra Kumar; Vijay Pratap Singh; Durgesh Kumar Tripathi; Sheo Mohan Prasad; Devendra Kumar ChauhanHydroponic experiments were conducted to investigate the effect of arsenic on seedlings of Wrightia arborea and Holoptelea integrifolia. Results revealed that W. arborea could tolerate much higher arsenic concentration than H. integrifolia. Therefore, further investigations were focused on W. arborea using higher arsenic concentrations (0.2–2.0 mM). Seedlings of W. arborea accumulated about 312–2147 and 1048–5688 mg/kg dry weight of arsenic in shoots and roots, respectively, following treatments with 0.2–1.5 mM of arsenic without exhibiting arsenic toxicity signs. However, arsenic at 2.0 mM caused decline in growth. Macronutrients content such as Ca, S (except at 2.0 mM), and K (only in root) increased while Mg, P, and K (shoot) decreased by arsenic treatments. However, the content of micronutrients was enhanced under arsenic treatments. Non-protein thiols (NP-SH) showed positive correlations with arsenic doses up to 0.2–1.5 mM but at 2.0 mM there was a decline in NP-SH thus suggesting important role of NP-SH in imparting arsenic tolerance. This study demonstrated that W. arborea that could tolerate arsenic concentrations up to 0.2–1.5 mM may be useful in arsenic phytoremediation programs. © 2015, Taylor & Francis Group, LLC.PublicationErratum Retraction notice to “The interplay between reactive oxygen and nitrogen species contributes in the regulatory mechanism of the nitro-oxidative stress induced by cadmium in Arabidopsis” [J. Hazard. Mater. 344 (2018) 1007–1024] (Journal of Hazardous Materials (2018) 344 (1007–1024), (S0304389417308877), (10.1016/j.jhazmat.2017.12.004))(Elsevier B.V., 2021) Shiliang Liu; Rongjie Yang; Durgesh Kumar Tripathi; Xi Li; Wei He; Mengxi Wu; Shafaqat Ali; Mingdong Ma; Qingsu Cheng; Yuanzhi PanThis article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor, after consultation with the corresponding author Dr. Shiliang Liu due to image issues. The article reused several images from the author's paper published in Environmental Pollution 239 (2018) 53-68 (which has been retracted due to image issues): Figures 1c, 1d, 2a, 2b, 2c, 4a, 9a and 9b. The article also plagiarized part of a paper from other authors that had appeared in Plant Physiology, 150, 229-243 (2009). The images that were reused were Fig. 5 a, 5c, 5e and 5g. This was brought to the editors’ attention via a letter to the editor. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. © 2020 Elsevier B.V.