Browsing by Author "Shekhar Mallick"

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A Successive Application Approach for Effective Utilization of Three Aquatic Plants in Arsenic Removal
(Springer International Publishing, 2017) Poonam; Munish Kumar Upadhyay; Ambedkar Gautam; Shekhar Mallick; Sudhakar Srivastava
In the present study, the performance of three selected aquatic plants [Hydrilla verticillata (H), Ceratophyllum demersum (C), and Lemna minor (L)] was evaluated for As removal from water when used in a successive application approach. The plants were subjected to 4 L of As-containing Hoagland medium (500 and 2500 μg L−1as low and high exposure, respectively) for a period of 21 days in slots of 7 days each. The results showed that total As removal in 21 days varied in different combinations. The best combination was HCL showing 27 and 18% As removal in low and high As treatments, respectively, followed by HLC (21 and 16%), and LCH (15% and 12%). The lowest As removal was achieved by LHC and CLH combination in low As treatment (11%) and by CLH in high As treatment (6%). Individual plant exhibited different removal potential from combination to combination and from application at various stages. The contribution of Hydrilla varied from 8 to 52%, Ceratophyllum from 18 to 64% and Lemna from 18 to 66%. The study advocates the combination of Hydrilla-Ceratophyllum-Lemna for achieving the maximum As removal in the same period. © 2017, Springer International Publishing Switzerland.
Ameliorative mechanisms of polyamines against abiotic stress in the rice plants
(Elsevier, 2018) Navin Kumar; Shekhar Mallick
Rice (Oryza sativa L.) is a staple food crop for about two thirds of the worlds’ population. Under stress conditions, the level of polyamines (PAs) biosynthesis in rice plants elevates. The ubiquitous PAs are involved in the regulation of plant development, physiological processes, and tolerance against diverse abiotic stresses. The two enzymes, viz. ornithine decarboxylase (ODC) and arginine decarboxylase (ADC), initiate the synthesis of PAs. From the PA, putrescine (Put), enzymatic synthesis of another two PAs that is, spermine (Spm) and spermidine (Spd) by Spm synthase and Spd synthase takes place. In rice plants, ADC mediated synthesis of Put, Spm, and Spd plays a crucial role in the amelioration of abiotic stress rather than the activity of ODC. The role of PAs in rice plants against drought stress, osmotic stress, and heat stress have been reported. The elevated level of PAs (Put, Spm, and Spd) is attributed to the ability of plants to counter stress by binding with the negative charged biomolecules that is, nucleic acids, proteins, and phospholipids in order to stabilize their structures under diverse abiotic stress conditions. The role of Spd and Put has been ascribed to heat tolerance through modulation of glutathione/GSSG, and fatty acid synthesis in order to recover from lipid peroxidation under oxidative stress in rice plants, respectively. The roles of PAs and the detailed mechanism of association with other metabolic pathways such as shikimate, phosphoenol pyruvate, Asada-Halliwell cycle, and nitrogen assimilation remains to be understood in detail. © 2019 Elsevier Inc. All rights reserved.
Enhancement in Ni–Cd Phytoremediation Efficiency of Helianthus annuus L. from Battery Waste Contaminated Soil by Bacterial Augmentation, Isolated from E-Waste Contaminated Sites
(Springer Science and Business Media Deutschland GmbH, 2023) Kriti; Babita Kumari; Gayatri Singh; Ambedkar Gautam; Geetgovind Sinam; Sunidhi Pal; Anshu; Kumkum Mishra; Shekhar Mallick
The study investigates enhancement of Ni–Cd phytoremediation efficiency of Helianthus annuus grown on Ni–Cd battery’s electrolyte (eW) contaminated soil augmented with two e-waste tolerant and metal solubilizing bacteria. H. annuus was grown outdoor on simulated eW contaminated soil (eW1%, eW2% and eW4%), augmented with Brucella intermedium (E1) and Bacillus velezensis (EW8), separately. The bioavailability of Ni (61–65%) and Cd (30–57%) within the soil was enhanced, with bacterial augmentation. Between both the bacteria, EW8 augmentation resulted higher Ni accumulation (µg g−1) viz. root (236.6), stem (66.5), leaves (18.5), and flower (10.8), respectively in H. annuus and also for Cd, i.e., 389.1, 100.5, 26.5 and 4.9, respectively against eW4%. Although the translocation factor was < 1 however, the bioaccumulation factor enhanced with bacterial augmentations viz. Ni (0.27–0.33) and Cd (0.19–0.34). EW8 enhanced metal bioavailability resulting in higher metal uptake in the plant, in contrast E1 having greater plant growth promotion activities, enhanced the plant growth. The antioxidant enzyme activities (SOD, APX, GST, GR, GPX and POD) were higher in plants with EW8 than E1. With rise in eW contamination, translocation of Cd increased over Ni. The improvement in the soil quality indices of the contaminated soil through phytoremediation was greater with bacterial augmentation than without. The rate of uptake of Ni (Vmax) was greatly enhanced by bacterial augmentation, however, it was effective within narrow range of metal concentration (Km), whereas, the maximum rate of Cd uptake was attained for a higher concentration, which was further enhanced by bacterial augmentation. Hence, phytoremediation of eW contaminated soil can improve the soil quality and is enhanced by tolerant bacterial augmentation, which has plant growth promotion activities. HighlightsBacillus velezensis EW8 enhances Ni–Cd bioavailability from eW contaminated soil.Brucella intermedia E1 exhibiting PGPA enhances Helianthus annuus growth.Ni uptake is higher at lower contamination and Cd uptake at higher contamination.The soil quality enhances with phytoremediation and greater with bacterial augmentation. © 2023, University of Tehran.
GABA accretion reduces Lsi-1 and Lsi-2 gene expressions and modulates physiological responses in Oryza sativa to provide tolerance towards arsenic
(Nature Publishing Group, 2017) Navin Kumar; Arvind Kumar Dubey; Atul Kumar Upadhyay; Ambedkar Gautam; Ruma Ranjan; Saripella Srikishna; Nayan Sahu; Soumit Kumar Behera; Shekhar Mallick
GABA counteracts wide range of stresses through regulation of GABA shunt pathway in plants. Although, GABA assisted tolerance against As toxicity in plants is still unexplored. We have examined GABA induced tolerance in rice seedlings with two exposure periods of GABA i.e., short term and long term. Results showed that accumulation of GABA reduced the expressions of Lsi-1 and Lsi-2 transporter genes, which ultimately decreased the accumulation of As in rice seedlings. The accumulation of GABA also modulated the gene expression of GABA shunt pathway and activity of antioxidant enzymes, which strongly induced the tolerance in plants. Antioxidant enzymes such as CAT, POD, GPX and SOD showed maximum alteration in activity with GABA accretion. In both exposure periods, long term accumulation of GABA was highly efficient to provide tolerance to plants against As(III), while higher level of GABA at short term was toxic. Tolerance responses of GABA towards As(III) was reflected by minimal changes in various physiological (WUE, A, gs, PhiPS2, qp, NPQ, ETR and Trmmol) and growth parameters with concomitant accumulation. Oxidative stress marker such as TBARS and H2O2 contents were reduced with GABA accumulation. These results suggested that GABA sturdily inhibits As accumulation and provides tolerance towards As(III). © 2017 The Author(s).
GABA mediated reduction of arsenite toxicity in rice seedling through modulation of fatty acids, stress responsive amino acids and polyamines biosynthesis
(Academic Press, 2019) Navin Kumar; Ambedkar Gautam; Arvind Kumar Dubey; Ruma Ranjan; Ashutosh Pandey; Babita Kumari; Gayatri Singh; Sachin Mandotra; Puneet Singh Chauhan; Saripella Srikrishna; Venkatesh Dutta; Shekhar Mallick
γ-aminobutyric acid (GABA) is a free amino acid, which helps to counteract biotic and abiotic stresses in plants. In the present study, two concentrations of GABA, i.e., 0.5 mM and 1 mM were applied to examine the tolerance of rice seedlings against As(III) (25 µM) toxicity, through the modulations of fatty acids (FAs), stress responsive amino acids (AAs) and polyamines (PAs) biosynthesis. Exogenous GABA (0.5 mM) application significantly reduced the H 2 O 2 and TBARS levels and recovered the growth parameters against As(III) stressed rice seedlings. Simultaneously, co-application of GABA (0.5 and 1 mM) and As(III), consistently enhanced the level of unsaturated fatty acids (USFA) (cis-10-pentadecanoic acid, oleic acid, α-linolenic acid and γ-linolenic acid), which was higher than saturated fatty acid (SFA). Among the USFAs, level of linolenic acid was found to be always higher with GABA application. Similarly, elevated level of AAs (proline, methionine, glutamic acid and cysteine) was also observed with the application of GABA (0.5 and 1 mM) in As(III) stressed seedlings. GABA also enhanced the expression of genes involved in the polyamine synthesis pathway namely arginine decarboxylase (AD), spermine (SPM) and spermidine (SPD) synthase against As(III) treatments, which was higher in roots than in shoots, resulting in enhanced root PAs level. Contrarily, the expression of S-adenosylmethionine decarboxylase (S-AMD) was significantly higher in shoots. Among all the PAs, level of putrescine (PUT) was found to be highest with GABA application. Overall, the study demonstrates that GABA (0.5 mM) at lower concentration plays a vital role in As(III) tolerance by enhancing the biosynthesis of USFA, AA and PA, reducing the level of TBARS and H 2 O 2 in rice seedlings. © 2019 Elsevier Inc.
Nickel and cadmium phytoextraction efficiencies of vetiver and lemongrass grown on Ni–Cd battery waste contaminated soil: A comparative study of linear and nonlinear models
(Academic Press, 2021) Kriti; Nikita Basant; Jogendra Singh; Babita Kumari; Geetgovind Sinam; Ambedkar Gautam; Gayatri Singh; Swapnil; Kumkum Mishra; Shekhar Mallick
A comparative assessment of the phytoremediation efficiency of two tolerant grass species viz. vetiver and lemongrass were performed in pots against simulated Ni–Cd battery electrolyte waste (EW) contaminated soil (EW1%, EW2% and EW4% w/w). Ni (μg g−1) accumulation was higher in shoots (36.8) and roots (252.9) of vetiver than in lemongrass (12.5 and 79.7, respectively). While the same trend was true for Cd (μg g−1) accumulation in vetiver and lemon grass roots (232.2 and 147.2, respectively), however, the accumulation in vetiver shoot (43.4) was less than in lemongrass (99.9). The bioaccumulation factor of metals in both grasses increased with EW contamination. Vetiver was tolerant towards EW toxicity than lemongrass, as it exhibited lesser decline in morphological parameters, lesser rise in TBARS against the doses of EW. The activities of SOD, APX, POD enzymes were higher in vetiver whereas, only GR in lemongrass. Multiple linear regression model show, pH had strong and positive influence over the Ni and Cd uptake by the plants whereas, phosphate, OM and bioavailable metals influenced negatively. The higher R2 (>0.9) and Chi-square values ≤ 1 in sigmoid non-linear model demonstrates robustness of the model for predicting the Ni and Cd accumulation (MHM) in both the grasses. Ni accumulation was higher than Cd, roots had greater accumulation of heavy metal and vetiver was a greater accumulator of Ni and Cd from EW the contaminated soil than lemongrass. © 2021 Elsevier Ltd
Reducing Arsenic Uptake in Cereal Crop Plants with Sugarcane Waste Application: A Comparative Study on the Effects on Physiology, Biochemistry, and Grain Nutrient Status
(Springer, 2023) Ambedkar Gautam; Nikita Basant; Navin Kumar; Kriti; Shiv Naresh Singh; Arvind Kumar Dubey; Gayatri Singh; Babita Kumari; Kavita Shah; Shekhar Mallick
C3 (Oryza sativa L.) and C4 (Zea mays L.) plants differ both in their carbon fixing mechanism, and thus, their responses toward stresses also differ. Owing to the mutually competitive nature of uptake between phosphate (iP) and arsenate (AsV) in plants, and given that the level of sucrose is also influenced by iP, interplay of their uptake mechanisms eventually results in reducing the AsV uptakes. The present study intends to comparatively assess the reduction in AsIII and AsV uptake and its toxicity between Oryza sativa L. and Zea mays L. when cultivated with sucrose-containing sugarcane wastes (SWs; bagasse, molasses, and pressmud) conducted under a simulated outdoor pot experiment. Overall improvement in growth, physiological performance, stress, and antioxidant response was exhibited in both the plants with SWs application. The SWs application also improved soil physiochemical parameters viz, pH, EC, OC, OM, and micronutrients. Application of SW also reduced the iAs accumulation in grains of both rice (50–87%) and maize (70–96%), along with enhancement in Fe (142%, and 122%, respectively), and Zn (132% and 131%, respectively). Most of the 17 grain’s amino acids (AAs) increased in maize against iAs stress, whereas Ser decreased in both, and Ile and Gly additionally in rice. Essential AAs viz. Phe, Thr, and Met are influenced negatively by iAs, whereas nonessential AAs viz. Cys, Ser, Pro, Gly in both the plant grains are positively influenced by iP and negatively by OC. Thus, the application of SWs containing residual sucrose > 9.5 µM g−1, through a fertilizer formulation or by direct soil amendments in iAs-contaminated soil can be an agronomic practice to reduce the iP fertilization and limit the iAs contamination in the food-chain. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Sucrose plays key role in amelioration of arsenic induced phytotoxicity through modulating phosphate and silicon transporters, physiological and biochemical responses in C3 (Oryza sativa L.) and C4 (Zea mays L.)
(Elsevier B.V., 2020) Ambedkar Gautam; Navin Kumar; Arvind Kumar Dubey; Ruma Ranjan; Nayan Sahu; Soumit Kumar Behera; Kavita Shah; Rudra Deo Tripathi; Shekhar Mallick
Sucrose is a precursor for several vital biomolecules and essential for growth of the plant. The present study investigated the interrelationship between sucrose (25 μM) and PO4 (iP) in amelioration of arsenic (iAs) [60 μM of AsIII and AsV] toxicity in C3 (Oryza sativa) and C4 (Zea mays) plants. Application of sucrose recovered the iAs induced phytotoxicity, morphological and physiological parameters in both C3 and C4 plant seedlings. Alternatively, iAs accumulation enhanced the endogenous level of sucrose in the seedlings. Also, sucrose suppressed the gene expression of low silicon transporters in both C3 and C4 plants, resulting in lower iAs uptake. Presence of iP, suppressed expression of root iP transporters which coincided with reduced iAs accumulation in maize root (23 %) over its AsIII, and that in shoots of both of C3 (12 %) and C4 (35 %) seedlings over AsV. However, the iP transporters in rice [OsPT-1, 6 & 9] and in maize (ZmPHT1;6, ZmPHT2;1, ZmPHT1;1), shoot and root, respectively, were upregulated with sucrose application, enhancing the iP accumulation. Sucrose application reduced the level of H2O2 and TBARS in both plants, while enhanced the thiolic compounds (GSH, cysteine and NPSH) and activities of antioxidant enzymes (APX, GPX and SOD) against iAs toxicity under both available and iP deprived conditions. The physiological parameters such as A, PhiPS2, gs and qP recovered whereas, NPQ was reduced with sucrose application, towards iAs treatments in both the seedlings. Overall, the results indicate that sucrose plays a vital role in the amelioration of iAs induced toxicity through modulation of iP and low silicon transporters, resulting in reducing the iAs accumulation, physiological parameters and antioxidants. © 2019 Elsevier B.V.
Transcriptome and proteome analyses reveal selenium mediated amelioration of arsenic toxicity in rice (Oryza sativa L.)
(Elsevier B.V., 2020) Reshu Chauhan; Surabhi Awasthi; Yuvraj Indoliya; Abhishek Singh Chauhan; Shashank Mishra; Lalit Agrawal; Sudhakar Srivastava; Sanjay Dwivedi; Poonam C. Singh; Shekhar Mallick; Puneet Singh Chauhan; Veena Pande; Debasis Chakrabarty; Rudra Deo Tripathi
Arsenic (As), a chronic poison and non-threshold carcinogen, is a food chain contaminant in rice, posing yield losses as well as serious health risks. Selenium (Se), a trace element, is a known antagonist of As toxicity. In present study, RNA seq. and proteome profiling, along with morphological analyses were performed to explore molecular cross-talk involved in Se mediated As stress amelioration. The repair of As induced structural deformities involving disintegration of cell wall and membranes were observed upon Se supplementation. The expression of As transporter genes viz., NIP1;1, NIP2;1, ABCG5, NRAMP1, NRAMP5, TIP2;2 as well as sulfate transporters, SULTR3;1 and SULTR3;6, were higher in As + Se compared to As alone exposure, which resulted in reduced As accumulation and toxicity. The higher expression of regulatory elements like AUX/IAA, WRKY and MYB TFs during As + Se exposure was also observed. The up-regulation of GST, PRX and GRX during As + Se exposure confirmed the amelioration of As induced oxidative stress. The abundance of proteins involved in photosynthesis, energy metabolism, transport, signaling and ROS homeostasis were found higher in As + Se than in As alone exposure. Overall, present study identified Se responsive pathways, genes and proteins involved to cope-up with As toxicity in rice. © 2020 Elsevier B.V.