BHU Institutional Repository :: Browsing by Author "Shrivastava, Manoj"

Browsing by Author "Shrivastava, Manoj"

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Application and research progress of Hydrilla verticillata in ecological restoration of water contaminated with metals and metalloids
(Elsevier B.V., 2021) Shrivastava, Manoj; Srivastava, Sudhakar
Hydrilla verticillata (L.f.) Royle is a widely distributed aquatic weed having prolific growth habits and a wide range of habitat. It can tolerate a wide range of physical and chemical conditions of water and can survive in low nutrient supply. Hydrilla is a potential accumulator of several metals and metalloids. The accumulation potential of Hydrilla plants is attributable to induced synthesis of thiol (-SH) containing ligands like glutathione and phytochelatins. Further, the uptake of metal(loid)s from both roots and leaves and movement in acropetal and basipetal directions allows plants to take up large quantity of metal(loid)s in short time span. Secondarily, antioxidant system is comprising of enzymatic and non-enzymatic components was found to rescue plants from metal(loid) induced oxidative stress. The used biomass of Hydrilla can be further utilized for composting, briquetting, pyrolysis and gasification. The high calorific fuel obtained from Hydrilla was found to have high heating value (44.06 MJ/kg) and low oxygen content (<3.5 wt %). The isolation of valuable chemical constituents like phytol from Hydrilla biomass has also been achieved. However, more field related studies focusing on optimum process development and cost benefit analyses are needed. This review discusses aspects of Hydrilla plants for phytoremediation of metals and metalloids. © 2021
Arsenic toxicity in rice (Oryza sativa L.) is influenced by sulfur supply: Impact on the expression of transporters and thiol metabolism
(Elsevier B.V., 2016) Srivastava, Sudhakar; Akkarakaran, Jincy Joseph; Sounderajan, Suvarna; Shrivastava, Manoj; Suprasanna, Penna
Arsenic (As) is a non-essential element whose entry into rice grains is an issue of public concern. The need, therefore, exists to understand the regulatory mechanisms of As accumulation and distribution patterns in plants. This study analyzed the effect of sulfur (S) supply on As accumulation and distribution in rice (Oryza sativa L. var. IR64) plants. Nine day old seedlings were grown in 0.798 mM S (Normal S), 0.2 mM S (Low S) and 0.003 mM S (Zero S) for 7 days and then subjected to AsIII (20 μM) exposure for 7-15 days. The concentration of As varied significantly in different S treatments with a consistent trend of decrease in As concentration in depleted S supply treatments on both 7 days and 15 days. Arsenic concentration declined from 726 μg g-1 DW to 537 μg g-1 DW in roots and from 29 μg g-1 DW to 8 μg g-1 DW in shoots at 7 days, and from 1536 μg g-1 DW to 1062 in roots and from 58 μg g-1 DW to 16 μg g-1 DW in shoots at 15 days, when S supply declined from normal to zero. The subcellular distribution of As was also found to vary with alteration in S supply and also differentially in shoot and root. In general, an up-regulation of sulfate transporters of groups 1 and 2 was observed while As transporters (Lsi1 and Lsi2) were down-regulated in response to As exposure to maintain sulfate and to regulate As levels. In spite of S depletion, an increase in cysteine, glutathione (GSH) and phytochelatin (PC) levels was observed upon As exposure. However, some negative impact of S depletion and As could be seen on the growth of plants. The study concluded that even in conditions of decreased S availability, plants continue to rely on thiol metabolism to tackle As levels and its toxicity effectively and altered subcellular distribution of As contributes only partially. © 2015 Elsevier B.V.
Copper accumulation and biochemical responses of Sesuvium portulacastrum (L.)
(Elsevier Ltd, 2019) Lokhande, Vinayak H.; Patade, Vikas Y.; Srivastava, Sudhakar; Suprasanna, Penna; Shrivastava, Manoj; Awasthi, Garima
Sesuvium portulacastrum (L.) is a halophytic phytoremediator plant with potential for significant accumulation of metals and metalloids. The present work evaluatedthe physiological and biochemical responses of Sesuvium plants to copper (Cu) exposure (100-500 lM) for 30 d in field conditions. Plants demonstrated significant copper accumulation that increased with the increase in Cu concentration of the medium (maximum 254 mg g-1 DW at 500 mM). The root dry weight was not significantly affected at 500 lM while shoot dry weight decreased significantly. Total soluble proteins, photosynthetic pigmentsand malondialdehye (MDA) were declined significantly beyond 100 lM after 30 d. Among metabolites and enzymes of thiol metabolism, total non-protein thiols (NP-SH), c-glutamylcysteine synthetase and glutathione reductase did not show significant effect while cysteine, serine acetyltransferase, and cysteine synthaseshowed a significant decline beyond 100 lM. The level of proline, glycine betaine and total phenolics also showed decreasing trend with the increase in Cu concentration. In conclusion, plantsare potential phytoextractor of Cu but do suffer from the toxic effects of Cu at high concentration of 500 lM. Sesuvium plants therefore appear suitable for use in phytoremediation purpose at low Cu concentrations (100 - 250 lM). © 2019 Elsevier Ltd.
Effect of zno nanoparticles on growth and biochemical responses of wheat and maize
(MDPI, 2021) Srivastav, Akansha; Ganjewala, Deepak; Singhal, Rakesh Kumar; Rajput, Vishnu D.; Minkina, Tatiana; Voloshina, Marina; Srivastava, Sudhakar; Shrivastava, Manoj
Zinc is an essential element that is also renowned for widespread contamination and toxicity at high concentrations. The present study was carried out to analyze the responses induced by lower, as well as higher, doses of zinc (0–200 mg/L), in the form of zinc oxide nanoparticles (ZnO NPs) in wheat and maize, for a period of 21 days. Accumulation of zinc increases with increasing Zn doses in both wheat and maize, with higher doses being in wheat (121 mg/kg in root and 66 mg/kg in shoot) than in maize (95 mg/kg in root and 48 mg/kg in shoot). The activity of alpha-amylase showed increase, while that of dehydrogenase decline, in response to ZnO NPs. The length and biomass of plants and photosynthetic pigments increased slightly upon ZnO NPs supply. Malondialdehyde content showed a progressive increase in root and shoot of both plants. However, in response, antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, and catalase) showed increase up to lower concentrations (100 mg/L) of ZnO NPs but decline variably at higher levels (150–200 mg/L) in wheat and maize. The results suggest that lower supply of ZnO NPs (100 mg/L) could be stimulatory to the growth of plants and can be recommended as a Zn fertilizer source for crop production. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Nanomaterials for managing abiotic and biotic stress in the soil-plant system for sustainable agriculture
(Royal Society of Chemistry, 2024) Ochoa, Loren; Shrivastava, Manoj; Srivastava, Sudhakar; Cota-Ruiz, Keni; Zhao, Lijuan; White, Jason C.; Hernandez-Viezcas, Jose Angel; Gardea-Torresdey, Jorge L.
As the global population steadily increases, the need to increase agricultural productivity has become more pressing. It is estimated that agricultural production needs to double in less than 30 years to meet the projected food demand. However, crop species are being cultivated under a range of increasingly challenging environmental stressors, including the effects of climate change and factors. To address these issues, nanotechnology has emerged as an enabling strategy to bolster plant resistance to the adverse effects of stressors and improve their overall performance. In this review, we evaluate recent research in this field, examining the strategies by which nanomaterials (NMs) and nanoparticles (NPs) have been used to facilitate enhanced tolerance to pests, excessive salinity in soil, pathogenic fungi, and other stressors. The intent is to focus on the mechanisms by which plants cope with environmental stressors at the physiological and molecular levels. We also examine how plants interact with and acquire NMs, with a specific focus on the mechanisms behind their beneficial effects regarding stress response. Our review also evaluates key knowledge gaps and offers suggestions on how to address them. Additionally, we discuss the potential of NMs to enhance agricultural production systems and highlight essential considerations for mitigating crop stress and promoting sustainable agriculture at a global scale. While the use of nanotechnology in the agricultural sector is growing and shows tremendous promise, more mechanistic studies and field-scale demonstrations are needed to fully understand and optimize the use of nanomaterials on plants stress tolerance in a changing climate. In addition, few studies conducted life cycle field experiments to verify the effects of nano-agrichemicals on yield and nutritional quality, and importantly, there is a lack of multiple-year and multiple-location experiments. Only by doing this can the technology-readiness-level of nano-enabled agro-technologies be improved and forwarded to commercial application. © The Royal Society of Chemistry 2025.
Soil and Plant Enzymes Responses to Zinc Oxide Nanoparticles in Submerged Rice (Oryza sativa L.) Ecosystem
(Walailak University, 2023) Srivastav, Akansha; Shukla, Anurakti; Singhal, Rakesh Kumar; Srivastava, Sudhakar; Ganjewala, Deepak; Shrivastava, Manoj
In the present study, the effects of zinc oxide nanoparticles (ZnO NPs) on rice (Oryza sativa L. cv. PB1509) plant growth were assessed in hydroponics (5, 10, 25, 50 mg L−1) and soil microcosm (5, 10, 25 50 mg kg−1) experiments. In both hydroponics and soil experiments, Zinc (Zn) accumulation in plant parts (roots, shoots and grains) was found to increase with increasing doses of ZnO NPs. Grains accumulated 29 mg kg−1 Zn at 50 mg kg−1 ZnO NPs in the soil experiment. In the hydroponics experiment, growth and photosynthetic pigments were induced by ZnO NPs up to 10 mg L−1, while higher doses of 25 and 50 mg L−1 were toxic to plant growth. Antioxidant enzyme activities (SOD, CAT, APX and GPX) were mostly increased or unaffected by all ZnO NPs doses. In soil experiments, acid and alkaline phosphatase activities were increased at 5 mg kg−1 followed by a declining trend. However, a significant decrease occurred only at 50 mg kg−1. Urease activity in soil was significantly increased at all doses of ZnO NPs, while the activity of dehydrogenase did not show any significant change up to 25 mg kg−1. The length of plants and photosynthetic pigments did not show much toxicity except root length beyond 10 mg kg−1; however, the biomass of plants including grains was significantly lower than control beyond 5 mg kg−1 dose. The activity of antioxidant enzymes (GPX, APX and CAT) showed a significant increase at all doses of ZnO NPs. The DTPA extractable Zn concentration in the soil was significantly elevated with increasing exposure concentrations of ZnO NPs. Based on hydroponics and soil experiments, this study suggests a dose of up to 10 mg L−1 or 10 mg kg−1 would be an appropriate dose for augmenting the growth of rice plants and Zn accumulation, and this can be practically utilized for rice plants growing in submerged conditions. © 2023, Walailak University. All rights reserved.
Zinc supplementation imparts tolerance to arsenite stress in Hydrilla verticillata (L.f.) Royle
(Taylor and Francis Inc., 2017) Srivastava, Sudhakar; Shrivastava, Manoj
The present study was aimed to analyze the effects of external Zn supply on arsenic (As) toxicity in Hydrilla verticillata (L.f.) Royle. The plants were exposed to arsenite (AsIII; 10 μM) with or without 50 and 100 μM Zn. The level of As accumulation (μg g−1 dw) after 2 and 4 days was not significantly affected by Zn supply. The plants showed a significant stimulation of the thiol metabolism (nonprotein thiols, cysteine, glutathione-S-transferase activity) upon As(III) exposure in the presence of Zn as compared to As(III) alone treatment. Besides, they did not experience significant toxicity, measured in terms of hydrogen peroxide and malondialdehyde accumulation, which are the indicators of oxidative stress. The minus Zn plants suffered from oxidative stress probably due to insufficient increase in thiols to counteract the stress. Stress amelioration by Zn supply was also evident from antioxidant enzyme activities, which came close to control levels with increasing Zn supply as compared to the increase observed in As(III) alone treatment. Variable Zn supply also modulated the level of photosynthetic pigments and restored them to control levels. In conclusion, an improved supply of Zn to plants was found to augment their ability to withstand As toxicity through enhanced thiol metabolism. © 2017 Taylor & Francis Group, LLC.

Browsing by Author "Shrivastava, Manoj"

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