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Soni S, Jha AB, Dubey RS, Sharma P. Nanowonders in agriculture: Unveiling the potential of nanoparticles to boost crop resilience to salinity stress. Sci Total Environ 2024; 925:171433. [PMID: 38458469 DOI: 10.1016/j.scitotenv.2024.171433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 02/10/2024] [Accepted: 03/01/2024] [Indexed: 03/10/2024]
Abstract
Soil salinization significantly affects crop production by reducing crop quality and decreasing yields. Climate change can intensify salinity-related challenges, making the task of achieving global food security more complex. To address the problem of elevated salinity stress in crops, nanoparticles (NPs) have emerged as a promising solution. NPs, characterized by their small size and extensive surface area, exhibit remarkable functionality and reactivity. Various types of NPs, including metal and metal oxide NPs, carbon-based NPs, polymer-based NPs, and modified NPs, have displayed potential for mitigating salinity stress in plants. However, the effectiveness of NPs application in alleviating plant stress is dependent upon multiple factors, such as NPs size, exposure duration, plant species, particle composition, and prevailing environmental conditions. Moreover, alterations to NPs surfaces through functionalization and coating also play a role in influencing plant tolerance to salinity stress. NPs can influence cellular processes by impacting signal transduction and gene expression. They counteract reactive oxygen species (ROS), regulate the water balance, enhance photosynthesis and nutrient uptake and promote plant growth and yield. The objective of this review is to discuss the positive impacts of diverse NPs on alleviating salinity stress within plants. The intricate mechanisms through which NPs accomplish this mitigation are also discussed. Furthermore, this review addresses existing research gaps, recent breakthroughs, and prospective avenues for utilizing NPs to combat salinity stress.
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Affiliation(s)
- Sunil Soni
- School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India
| | - Ambuj Bhushan Jha
- School of Life Sciences, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India
| | - Rama Shanker Dubey
- Central University of Gujarat, Sector-29, Gandhinagar 382030, Gujarat, India
| | - Pallavi Sharma
- School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India.
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Sharma P, Jha AB, Dubey RS. Addressing lanthanum toxicity in plants: Sources, uptake, accumulation, and mitigation strategies. Sci Total Environ 2024; 929:172560. [PMID: 38641102 DOI: 10.1016/j.scitotenv.2024.172560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/06/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
Lanthanum (La), the second most abundant rare earth element (REE) is emerging as an environmental issue, with the potential to impact ecosystems and human health. Major sources of soil contamination by La include agricultural, and industrial activities. Lanthanum is non-essential for plant growth but accumulates in various plant parts. The uptake of La by plants is intricately influenced by various factors such as soil pH, redox potential, cation exchange capacity, presence of organic acids and rhizosphere composition. These factors significantly impact the availability and absorption of La ions. Lanthanum impact on plants depends on soil characteristics, cultivated species, developmental stage, La concentration, treatment period, and growth conditions. Excessive La concentrations affect cell division, DNA structure, nutrient uptake, and photosynthesis and induce toxicity symptoms. Plants employ detoxification mechanisms like vacuolar sequestration, osmolyte synthesis, and antioxidant defense system. However, higher concentrations of La can overwhelm these defense mechanisms, leading to adverse effects on plant growth and development. Further, accumulation of La in plants increases the risk for human exposure. Strategies to mitigate La toxicity are, therefore, vital for ecosystem protection. The application of phytoremediation, supplementation, chelation, amendments, and biosorption techniques contributes to the mitigation of La toxicity. This review provides insights into La sources, uptake, toxicity, and alleviation strategies in plants. Identifying research gaps and discussing advancements aims to foster a holistic understanding and develop effective strategies for protecting plant health and ecosystem resilience against La contamination.
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Affiliation(s)
- Pallavi Sharma
- School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India.
| | - Ambuj Bhushan Jha
- School of Life Sciences, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India
| | - Rama Shanker Dubey
- Central University of Gujarat, Sector-29, Gandhinagar 382030, Gujarat, India
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Soni S, Jha AB, Dubey RS, Sharma P. Mitigating cadmium accumulation and toxicity in plants: The promising role of nanoparticles. Sci Total Environ 2024; 912:168826. [PMID: 38042185 DOI: 10.1016/j.scitotenv.2023.168826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 10/23/2023] [Accepted: 11/22/2023] [Indexed: 12/04/2023]
Abstract
Cadmium (Cd) is a highly toxic heavy metal that adversely affects humans, animals, and plants, even at low concentrations. It is widely distributed and has both natural and anthropogenic sources. Plants readily absorb and distribute Cd in different parts. It may subsequently enter the food chain posing a risk to human health as it is known to be carcinogenic. Cd has a long half-life, resulting in its persistence in plants and animals. Cd toxicity disrupts crucial physiological and biochemical processes in plants, including reactive oxygen species (ROS) homeostasis, enzyme activities, photosynthesis, and nutrient uptake, leading to stunted growth and reduced biomass. Although plants have developed defense mechanisms to mitigate these damages, they are often inadequate to combat high Cd concentrations, resulting in yield losses. Nanoparticles (NPs), typically smaller than 100 nm, possess unique properties such as a large surface area and small size, making them highly reactive compared to their larger counterparts. NPs from diverse sources have shown potential for various agricultural applications, including their use as fertilizers, pesticides, and stress alleviators. Recently, NPs have emerged as a promising strategy to mitigate heavy metal stress, including Cd toxicity. They offer advantages, such as efficient absorption by crop plants, the reduction of Cd uptake, and the enhancement of mineral nutrition, antioxidant defenses, photosynthetic parameters, anatomical structure, and agronomic traits in Cd-stressed plants. The complex interaction of NPs with calcium ions (Ca2+), intracellular ROS, nitric oxide (NO), and phytohormones likely plays a significant role in alleviating Cd stress. This review aims to explore the positive impacts of diverse NPs in reducing Cd accumulation and toxicity while investigating their underlying mechanisms of action. Additionally, it discusses research gaps, recent advancements, and future prospects of utilizing NPs to alleviate Cd-induced stress, ultimately promoting improved plant growth and yield.
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Affiliation(s)
- Sunil Soni
- School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India
| | - Ambuj Bhushan Jha
- School of Life Sciences, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India
| | - Rama Shanker Dubey
- Central University of Gujarat, Sector-29, Gandhinagar 382030, Gujarat, India
| | - Pallavi Sharma
- School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India.
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Soni S, Jha AB, Dubey RS, Sharma P. Alleviation of chromium stress in plants using metal and metal oxide nanoparticles. Environ Sci Pollut Res Int 2023:10.1007/s11356-023-28161-0. [PMID: 37358773 DOI: 10.1007/s11356-023-28161-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 06/03/2023] [Indexed: 06/27/2023]
Abstract
Chromium (Cr), one of the hazardous pollutants, exists predominantly as Cr(VI) and Cr(III) in the environment. Cr(VI) is more toxic than Cr(III) due to its high mobility and solubility. Elevated levels of Cr in agricultural soil due to various anthropogenic activities cause Cr accumulation in plants, resulting in a significant reduction in plant yield and quality due to Cr-induced physiological, biochemical and molecular alterations. It can infiltrate the food chain through crop plants and cause harmful effects in humans via biomagnification. Cr(VI) is linked to cancer in humans. Therefore, mitigation strategies are required to remediate Cr-polluted soils and limit its accumulation in plants for safe food production. Recent research on metal and metal oxide nanoparticles (NPs) has shown that they can effectively reduce Cr accumulation and phytotoxicity. The effects of these NPs are influenced by their type and dose, exposure method, plant species and experimental settings. In this review, we present an up-to-date compilation and comprehensive analysis of the existing literature regarding the process of uptake and distribution of Cr and impact and potential mechanisms of metal and metal oxide nanoparticles led mitigation of Cr-induced stress in plants. We have also discussed recent developments, existing research gaps and future research directions in the field of Cr stress mitigation by NPs in plants. Overall, this review can provide valuable insights in reducing Cr accumulation and toxicity using metal and metal oxide nanoparticles, thereby promoting safe and sustainable cultivation of food and phytostabilization of Cr-polluted soil.
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Affiliation(s)
- Sunil Soni
- School of Environment and Sustainable Development, Central University of Gujarat, Sector 30, Gandhinagar, Gujarat, 382030, India
| | - Ambuj Bhushan Jha
- Crop Development Centre/Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
- School of Life Sciences, Central University of Gujarat, Sector 30, Gandhinagar, Gujarat, 382030, India
| | - Rama Shanker Dubey
- Central University of Gujarat, Sector 29, Gandhinagar, Gujarat, 382030, India
| | - Pallavi Sharma
- School of Environment and Sustainable Development, Central University of Gujarat, Sector 30, Gandhinagar, Gujarat, 382030, India.
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Zhou J, Wan Z, Gali KK, Jha AB, Nickerson MT, House JD, Tar’an B, Warkentin TD. Quantitative trait loci associated with amino acid concentration and in vitro protein digestibility in pea ( Pisum sativum L.). Front Plant Sci 2023; 14:1083086. [PMID: 36968409 PMCID: PMC10038330 DOI: 10.3389/fpls.2023.1083086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
With the expanding interest in plant-based proteins in the food industry, increasing emphasis is being placed on breeding for protein concentration and quality. Two protein quality traits i.e., amino acid profile and protein digestibility, were assessed in replicated, multi-location field trials from 2019 to 2021 in pea recombinant inbred line population PR-25. This RIL population was targeted specifically for the research of protein related traits and its parents, CDC Amarillo and CDC Limerick, had distinct variations in the concentration of several amino acids. Amino acid profile was determined using near infrared reflectance analysis, and protein digestibility was through an in vitro method. Several essential amino acids were selected for QTL analysis, including lysine, one of the most abundant essential amino acids in pea, and methionine, cysteine, and tryptophan, the limiting amino acids in pea. Based on phenotypic data of amino acid profiles and in vitro protein digestibility of PR-25 harvested in seven location-years, three QTLs were associated with methionine + cysteine concentration, among which, one was located on chromosome 2 (R2 = 17%, indicates this QTL explained 17% phenotypic variation of methionine + cysteine concentration within PR-25), and two were located on chromosome 5 (R2 = 11% and 16%). Four QTLs were associated with tryptophan concentration and are located on chromosome 1 (R2 = 9%), chromosome 3 (R2 = 9%), and chromosome 5 (R2 = 8% and 13%). Three QTLs were associated with lysine concentration, among which, one was located on chromosome 3 (R2 = 10%), the other two were located on chromosome 4 (R2 = 15% and 21%). Two QTLs were associated with in vitro protein digestibility, one each located on chromosomes 1 (R2 = 11%) and 2 (R2 = 10%). QTLs associated with in vitro protein digestibility, and methionine + cysteine concentration on chromosome 2 were identified to be co-localized with known QTL for total seed protein concentration in PR-25. QTLs associated with tryptophan and methionine + cysteine concentration co-localized on chromosome 5. The identification of QTLs associated with pea seed quality is an important step towards marker-assisted selection of breeding lines with improved nutritional quality, which will further boost the competitiveness of pea in plant-based protein markets.
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Affiliation(s)
- Junsheng Zhou
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | - Zhongyang Wan
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Krishna Kishore Gali
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | - Ambuj Bhushan Jha
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | - Michael T. Nickerson
- Department of Food and Bioproduct Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - James D. House
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada
- Richardson Centre for Food Technology and Research, University of Manitoba, Winnipeg, MB, Canada
| | - Bunyamin Tar’an
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | - Thomas D. Warkentin
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
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Zhou J, Gali KK, Jha AB, Tar’an B, Warkentin TD. Identification of Quantitative Trait Loci Associated with Seed Protein Concentration in a Pea Recombinant Inbred Line Population. Genes (Basel) 2022; 13:1531. [PMID: 36140699 PMCID: PMC9498679 DOI: 10.3390/genes13091531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/23/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022] Open
Abstract
This research aimed to identify quantitative trait loci (QTLs) associated with seed protein concentration in a recombinant inbred line (RIL) population of pea and aimed to validate the identified QTLs using chromosome segment-introgressed lines developed by recurrent backcrossing. PR-25, an RIL population consisting of 108 F7 bulked lines derived from a cross between CDC Amarillo (yellow cotyledon) and CDC Limerick (green cotyledon), was used in this research. The RIL population was genotyped using an Axiom 90K SNP array. A total of 10,553 polymorphic markers were used for linkage map construction, after filtering for segregation distortion and missing values. The linkage map represents 901 unique loci on 11 linkage groups which covered a map distance of 855.3 Centimorgans. Protein concentration was assessed using near-infrared (NIR) spectroscopy of seeds harvested from field trials in seven station-years in Saskatchewan, Canada, during the 2019-2021 field seasons. Three QTLs located on chromosomes 2, 3 and 5 were identified to be associated with seed protein concentration. These QTLs explained 22%, 11% and 17% of the variation for protein concentration, respectively. The identified QTLs were validated by introgression lines, developed by marker-assisted selection of backcross lines for introgression of corresponding chromosome segments (~1/4 chromosome) harboring the QTL regions. Introgression line PR-28-7, not carrying any protein-related QTLs identified in this study, was 4.7% lower in protein concentration than CDC Amarillo, the lower protein parent of PR-25 which carried one identified protein-related QTL. The SNP markers located at the peak of the three identified QTLs will be converted into breeder-friendly KASP assays, which will be used for the selection of high-protein lines from segregating populations.
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Affiliation(s)
| | | | | | | | - Thomas D. Warkentin
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK S7N 5A8, Canada
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Singh R, Jha AB, Misra AN, Sharma P. Entrapment of enzyme in the presence of proline: effective approach to enhance activity and stability of horseradish peroxidase. 3 Biotech 2020; 10:155. [PMID: 32181117 DOI: 10.1007/s13205-020-2140-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 02/15/2020] [Indexed: 11/30/2022] Open
Abstract
In this report, activity and stability of horseradish peroxidase (HRP) entrapped in polyacrylamide gel in the presence of proline (HEP) are compared with that of enzyme entrapped in absence of proline (HE). Within polyacrylamide (8%) beads, 80% entrapment yield for peroxidase was observed in the presence as well as absence of proline. The HEP (1.5 M proline) showed 170% higher activity compared to HE. HEP also showed significant increase in K M, V max and K cat. At 8th cycle of use, HEP retained 40% of its activity, whereas HE retained only 10% of activity. In addition, in comparison with HE, HEP showed increased storage stability and thermo-stability. HEP showed higher activity compared to HE over an extensive range of pH (4-8), temperature (30-80 °C) and inhibitors such as NaN3, Cd2+ and Pb2+. Our results suggest that peroxidase entrapment in polyacrylamide gel in the presence of proline can be a useful approach for increasing activity and stability of horseradish peroxidase.
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Affiliation(s)
- Rajani Singh
- 1Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, 835205 India
| | - Ambuj Bhushan Jha
- 2Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK S7N5A8 Canada
| | - Amarendra Narayan Misra
- 1Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, 835205 India
- Khallikote University, Berhampur, Odisha 761008 India
| | - Pallavi Sharma
- 1Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, 835205 India
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Singh R, Jha AB, Misra AN, Sharma P. Differential responses of growth, photosynthesis, oxidative stress, metals accumulation and NRAMP genes in contrasting Ricinus communis genotypes under arsenic stress. Environ Sci Pollut Res Int 2019; 26:31166-31177. [PMID: 31456154 DOI: 10.1007/s11356-019-06243-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
Effect of arsenate [As(V)] on biomass, photosynthetic rate, stomatal conductance, transpiration, oxidative stress, accumulation of As, Fe, Zn, Cu and Mn and expression of NRAMP genes was investigated in As(V) tolerant and sensitive genotypes of bioenergy crop Ricinus communis. As(V) treatments (100 and 200 μM) led to significant reduction in root and leaf biomass, photosynthetic rate, stomatal conductance and transpiration in GCH 2 and GCH 4 genotypes but no significant change or increase was observed in WM and DCH 177 genotypes. No significant difference was observed in hydrogen peroxide content and lipid peroxidation in As(V)-treated tolerant genotypes compared to control, whereas these parameters enhanced significantly in As(V)-treated sensitive genotypes. GCH 2 accumulated around two times As in leaves and showed significant reduction in concentration of Zn and Mn in the leaves and roots due to 200 μM As(V) treatment compared to WM. NRAMP genes are critical for uptake and distribution of essential divalent metal cations, photosynthesis and controlled production of reactive oxygen species in plants. RcNRAMP2, RcNRAMP3 and RcNRAMP5 genes showed differential expression in response to 200 μM As(V) in GCH 2 and WM suggesting that NRAMP genes are associated with differential responses of WM and GCH 2 genotypes to As(V) stress.
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Affiliation(s)
- Rajani Singh
- Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, Jharkhand, 835205, India
| | - Ambuj Bhushan Jha
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Amarendra Narayan Misra
- Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, Jharkhand, 835205, India
- Khallikote Cluster University, Berhampur, Odisha, 760001, India
| | - Pallavi Sharma
- Department of Life Sciences, Central University of Jharkhand, Brambe, Ranchi, Jharkhand, 835205, India.
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Singh S, Singh R, Bhushan Jha A, Misra AN, Sharma P. Amorphophallus paeoniifolius corm: A potential source of peroxidase for wide applications. International Journal of Food Properties 2017. [DOI: 10.1080/10942912.2016.1247363] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Shikha Singh
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi, India
| | - Rajani Singh
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi, India
| | - Ambuj Bhushan Jha
- Crop Development Centre, Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | | | - Pallavi Sharma
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi, India
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Mishra S, Jha AB, Dubey RS. Arsenite treatment induces oxidative stress, upregulates antioxidant system, and causes phytochelatin synthesis in rice seedlings. Protoplasma 2011; 248:565-77. [PMID: 20857150 DOI: 10.1007/s00709-010-0210-0] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 09/07/2010] [Indexed: 05/08/2023]
Abstract
The effects of arsenite treatment on generation of reactive oxygen species, induction of oxidative stress, response of antioxidative system, and synthesis of phytochelatins were investigated in two indica rice (Oryza sativa L.) cvs. Malviya-36 and Pant-12 grown in sand cultures for a period of 5-20 days. Arsenite (As(2)O(3); 25 and 50 μM) treatment resulted in increased formation of superoxide anion (O (2) (.-) ), elevated levels of H(2)O(2) and thiobarbituric acid reactive substances, showing enhanced lipid peroxidation. An enhanced level of ascorbate (AA) and glutathione (GSH) was observed irrespective of the variation in the level of dehydroascorbate (DHA) and oxidized glutathione (GSSG) which in turn influenced redox ratios AA/DHA and GSH/GSSG. With progressive arsenite treatment, synthesis of total acid soluble thiols and phytochelatins (PC) increased in the seedlings. Among antioxidative enzymes, the activities of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), total ascorbate peroxidase (APX, EC 1.11.1.11), chloroplastic ascorbate peroxidase, guaiacol peroxidase (EC 1.11.1.7), monodehydroascorbate reductase (EC 1.6.5.4), and glutathione reductase (EC 1.6.4.2) increased in arsenite treated seedlings, while dehyroascorbate reductase (EC 1.8.5.1) activity declined initially during 5-10 days and increased thereafter. Results suggest that arsenite treatment causes oxidative stress in rice seedlings, increases the levels of many enzymatic and non-enzymatic antioxidants, and induces synthesis of thiols and PCs, which may serve as important components in mitigating arsenite-induced oxidative damage.
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Affiliation(s)
- Shruti Mishra
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi, India
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Abstract
We studied in the seedlings of two rice cultivars (Malviya-36 and Pant-12) the effect of increasing levels of arsenic in situ on the content of sugars and the activity of several enzymes of starch and sucrose metabolism: alpha-amylase (EC 3.2.1.1), beta-amylase (EC 3.2.1.2), starch phosphorylase (EC 2.4.1.1), acid invertase (EC 3.2.1.26), sucrose synthase (EC 2.4.1.13) and sucrose phosphate synthase (EC 2.4.1.14). During a growth period of 10-20 d As2O3 at 25 and 50 microM in the growth medium caused an increase in reducing, non-reducing and total soluble sugars. An increased conversion of non-reducing to reducing sugars was observed concomitant with As toxicity. The activities of alpha-amylase, beta-amylase and sucrose phosphate synthase declined, whereas starch phosphorylase, acid invertase and sucrose synthase were found to be elevated. Results indicate that in rice seedlings arsenic toxicity causes perturbations in carbohydrate metabolism leading to the accumulation of soluble sugars by altering enzyme activity. Sucrose synthase possibly plays a positive role in synthesis of sucrose under As-toxicity.
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Affiliation(s)
- A B Jha
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi, India
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