Flavonoids are characterized as the low molecular weight polyphenolic compounds universally distr... more Flavonoids are characterized as the low molecular weight polyphenolic compounds universally distributed in planta. They are a chemically varied group of secondary metabolites with a broad range of biological activity. The increasing amount of evidence has demonstrated the various physiological functions of flavonoids in stress response. In this paper, we provide a brief introduction to flavonoids’ biochemistry and biosynthesis. Then, we review the recent findings on the alternation of flavonoid content under different stress conditions to come up with an overall picture of the mechanism of involvement of flavonoids in plants’ response to various abiotic stresses. The participation of flavonoids in antioxidant systems, flavonoid-mediated response to different abiotic stresses, the involvement of flavonoids in stress signaling networks, and the physiological response of plants under stress conditions are discussed in this review. Moreover, molecular and genetic approaches to tailoring...
The dipotassium phosphate (K2HPO4) is a source of phosphorus (P), which is an essential micronutr... more The dipotassium phosphate (K2HPO4) is a source of phosphorus (P), which is an essential micronutrient for plant growth and reproduction and also acts as a stress alleviator against abiotic stresses. Therefore, it could also become a potential mineral to cope up with zinc oxide nanoparticles’ (ZnONPs) toxicity in crops. This study primarily includes synthesis, characterization and differential toxic impacts of ZnONPs on two crop plantsThis study includes synthesis, characterization and differential toxic impacts of ZnONPs on two crop plants, i.e. Triticum aestivum and Solanum lycopersicum, as well as assuage the toxic impacts of ZnONPs through nutrient management approach implied via supplementation of P. The growth and physiological changes under toxic doses of ZnONPs and ameliorative potential of P in crop plants were examined by analysing growth, intracellular Zn accumulation, photosynthetic pigment contents, the kinetics of photosystem II (PS II) photochemistry, root cell anatomy...
Abstract Small RNAs are single-stranded noncoding RNA molecules of ~20–30 nucleotides known to pl... more Abstract Small RNAs are single-stranded noncoding RNA molecules of ~20–30 nucleotides known to play a significant role in several cellular mechanisms. These small RNAs comprised small-interference RNAs (siRNAs), microRNAs (miRNAs), and PIWI (P element–induced wimpy testis)-interacting RNAs. The small RNAs regulate gene expression at the transcriptional and posttranscriptional level, and the whole mechanism of gene regulation by small RNAs is referred to as RNA interference. Among small RNAs, miRNAs and siRNAs are found in majority of eukaryotes, while piRNAs are found only in animals. miRNAs are an evolutionarily conserved group of ~22 nucleotides long-endogenous noncoding RNAs, which control the gene expressions, while posttranscriptionally via either transcript cleavage, translation repression, or both. It is becoming apparent that miRNAs assist various regulatory mechanisms such as developmental timing, host–pathogen interaction, cell differentiation, cell proliferation, apoptosis, as well as tumorigenesis. miRNA acts as a regulatory element and is modulated by various effectors such as single nucleotide polymorphism (SNP), miRNA editing, methylation, and circadian clock.
Nanomaterials in Plants, Algae, and Microorganisms
Objective: Since structural changes of adsorbed protein are necessary for cellular uptake of nano... more Objective: Since structural changes of adsorbed protein are necessary for cellular uptake of nanoparticles (NPs) it is of prime importance to know about structural changes of bovine serum albumin (BSA) when it interacts with CuO NPs-a potential new antitumor drug. Methods: CuO NPs prepared by sol-gel technique were characterized by x-ray diffraction (XRD) and tunneling electron microscope (TEM) techniques. The conformational changes induced by CuO NPs on BSA were studied by various spectroscopic techniques such as steady state and time-resolved fluorescence measurements. The changes in fluorescence emission parameters such as fluorescence intensity, fluorescence emission maximum and lifetimes of fluorescent residues in BSA were studied. Results: XRD analysis showed the average particle size as 32 nm. The TEM micrograph showed particles of different size varying from 10 to 45 nm. Fluorescence quenching was confirmed due to a decrease in fluorescence intensity of CuO NPs-BSA complex. The analysis of lifetime measurements indicated BSA contained two tryptophan (trp) residues that fluoresced in different environments. Static quenching mechanism was confirmed by time-resolved measurements when BSA interacted with CuO NPs. Conclusion: Minor structural changes of BSA protein were observed during the interaction studies.
In agriculture, abiotic stress is one of the critical issues impacting the crop productivity and ... more In agriculture, abiotic stress is one of the critical issues impacting the crop productivity and yield. Such stress factors lead to the generation of reactive oxygen species, membrane damage, and other plant metabolic activities. To neutralize the harmful effects of abiotic stress, several strategies have been employed that include the utilization of nanomaterials. Nanomaterials are now gaining attention worldwide to protect plant growth against abiotic stresses such as drought, salinity, heavy metals, extreme temperatures, flooding, etc. However, their behavior is significantly impacted by the dose in which they are being used in agriculture. Furthermore, the action of nanomaterials in plants under various stresses still require understanding. Hence, with this background, the present review envisages to highlight beneficial role of nanomaterials in plants, their mode of action, and their mechanism in overcoming various abiotic stresses. It also emphasizes upon antioxidant activitie...
Abstract Heavy metal (HM) pollution in environment occurs due to their release from natural resou... more Abstract Heavy metal (HM) pollution in environment occurs due to their release from natural resources, such as rocks, ore minerals, volcanoes, weathering, and various anthropogenic activities like urban advancement, electricity generation, mining, and refinery industries. HMs are transition metals, which possess atomic mass more than 0.002 kg, weight about 5 N/m3, and density greater than 5 g/cm3. These metals are categorized as essential, such as copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), iron (Fe), cobalt (Co), molybdenum (Mo), selenium (Se), and nonessential metals. Essential HMs play vital regulatory roles in several cellular reactions, including electron transfer, in enzyme activation, in redox reaction, as well as in the synthesis of pigments, whereas nonessential metals, such as chromium (Cr), cadmium (Cd), lead (Pb), silver (Ag), mercury (Hg), and arsenic (As), have no role in any biological reaction, thus cause toxic impacts even at low concentrations by competing with crucial elements at protein-binding sites. Although when the amount of these metals increases beyond the optimum point, they cause toxicity in plants, by decreasing growth, causing soil quality deterioration and by affecting the yield. Toxicity of HMs depends on the concentration, reactivity, as well as on their oxidation capacity. Crops are more susceptible to these HMs, as they transport HMs to organisms through the food chain. HM-stressed plant shows alteration in cellular mechanisms and gene regulation. These HMs generate free radicals in cells, which further cause toxicity in plants. Nonessential metals deliberate various physiological reactions, through the alteration in biomolecules and in regulatory proteins or by replacement of crucial metals, therefore disturb the integrity of biomolecules and affects antioxidant defense system by generating reactive oxygen species. Plant acquires several defense approaches to safeguard against metal toxicity; such processes include sequestration, compartmentalization, exclusion, and inactivation by the secretion of organic ligands. Beside this, plants also induce antioxidant system as well as maintain the metal homeostasis by restricting the metal bioavailability.
Journal of emerging technologies and innovative research, 2020
Silver nanoparticles (AgNPs) are used in several commercial products, medical and diagnostic trea... more Silver nanoparticles (AgNPs) are used in several commercial products, medical and diagnostic treatments, and as nano-pesticide and nano-herbicide. On release, it contaminates the environment and ultimately reaches the agriculture field, causes an alteration in the plant growth and development, whereas their negatives impacts could be restored by the exogenous application of indole-3-acetic acid (IAA). Therefore, the present study has been carried out to examine the potential role of IAA on the toxicity of AgNPs in Oryza sativa seedlings. AgNPs at both doses (200 and 500 μM) showed a remarkable decline in growth, photosynthetic pigments, and protein content. AgNPs also negatively affected the kinetics of photosystem II (PS II) photochemistry that leads to oxidative stress as confirmed by invitro and in-vivo visualization of superoxide radicle (SOR) and hydrogen peroxide (H2O2) that ultimately cause cell death. While the addition of IAA along with AgNPs mitigates the toxicity by incre...
Copper oxide nanoparticles (CuONPs) toxicity has greatly affected the environment and particularl... more Copper oxide nanoparticles (CuONPs) toxicity has greatly affected the environment and particularly plants. It causes rapid changes in plant morphology and physiology; however, the changes can be restored via exogenous supplementation of Calcium (Ca). Thus, the present work has been undertaken to elucidate the impacts of Ca supplementation on reducing the CuONPs toxicity in S. lycopersicum. CuONPs at both the doses (500 and 1000 μM) showed significant reduction in growth, protein content, photosynthetic pigments, PS II photochemistry, contrastingly the reactive oxygen species (SOR and H2O2) were significantly raised as confirmed by invitro and in-vivo visualization of SOR and H2O2 that eventually leads to cell death as evidenced. Now days the nutrient management techniques have been widely used for the release of toxic effects caused by the pollutants in plants. In this study, the toxicity alleviation is achieved by exogenous application of calcium (Ca). Ca is a macronutrient that ac...
Histochemistry is an essential analytical tool interfacing extensively with plant science. The li... more Histochemistry is an essential analytical tool interfacing extensively with plant science. The literature is indeed constellated with examples showing its use to decipher specific physiological and developmental processes, as well as to study plant cell structures. Plant cell structures are translucent unless they are stained. Histochemistry allows the identification and localization, at the cellular level, of biomolecules and organelles in different types of cells and tissues, based on the use of specific staining reactions and imaging. Histochemical techniques are also widely used for the in vivo localization of promoters in specific tissues, as well as to identify specific cell wall components such as lignin and polysaccharides. Histochemistry also enables the study of plant reactions to environmental constraints, e.g. the production of reactive oxygen species (ROS) can be traced by applying histochemical staining techniques. The possibility of detecting ROS and localizing them a...
The action of nanoparticles is increasingly being studied in recent years to minimize their toxic... more The action of nanoparticles is increasingly being studied in recent years to minimize their toxic impacts. Besides this, efforts are also being made to minimize their toxicity in crop plants by using various chemicals, i.e. nutrients, donors of signalling molecules, plant hormones, etc. However, associated alleviatory mechanisms are still not well known. Therefore, in the present study, we have investigated the toxicity of CuONPs and its mitigation by exogenously applied calcium (Ca). The focus was on whether indole-3-acetic acid (IAA) or endogenous nitric oxide (NO) has any role in accomplishing this task. CuONPs declined wheat growth due to increased accumulation of Cu and oxidative stress markers such as superoxide radicals, hydrogen peroxide and lipid peroxidation (malondialdehyde) and it was also accompanied by a decline in endogenous NO. CuONPs also altered the redox status of ascorbate and glutathione by inhibiting the activity of their regenerating enzymes. This collectively leads to cell death in wheat seedlings. However, exogenous supplementation of Ca mitigated toxic effects of CuONPs by reducing the excess accumulation of Cu, which caused remarkable enhancement in growth, protein contents, photosynthetic pigments, and endogenous nitric oxide; altogether protecting wheat roots from cell death. Interestingly, addition of 2,3,5-triiodobenzoic acid (TIBA) further increased CuONPs toxicity even in the presence of Ca, but the addition of IAA rescued this effect of TIBA. These results clearly show that Ca mitigates CuONPs toxicity in wheat seedlings by involving IAA. Further, the results also showed that endogenous NO has a positive and indispensable role in Ca-mediated mitigation of CuONPs toxicity in wheat seedlings. This article is protected by copyright. All rights reserved.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Heavy metal (HMs) pollution is regarded as one of the major concerns for soil and water, causing ... more Heavy metal (HMs) pollution is regarded as one of the major concerns for soil and water, causing varieties of toxic and stress effects on plants and ecosystems. It has become one of the important limiting factors to crop productivity and quality. Due to an ever-increasing population growth and food demands, this situation has further worsened. Rice, a leading staple food crop that feeds more than 50% populations of the world, is constantly affected by abiotic stressors including HMs. In most of the countries, a major source of HM intake by humans is the rice grain produced through the paddy soils contaminated with HMs such as As, Al, Cu, Cr, Cd, Pb, Hg, Mn, Se, and Zn. Thus, gradual agglomeration of HMs in rice grains and their subsequent transfer to the food chain is a major menace to agriculture and human health. In recent years, several studies examined the impact of HMs toxicity on rice at multiple levels: molecular, biochemical, physiological, cellular and tissue, and demonstrated a correlation between HMs toxicity and the decreasing trend in rice productivity. Therefore, it is necessary to understand the interaction of HMs with rice crop spanning from the cell to whole plant level and devise appropriate effective means to alleviate these stress responses. This review focuses on tracing the pathways involved in stress responses and stress tolerance mechanisms displayed by different varieties of rice. However, it is essential to uncover the mechanisms related to stress responses in rice for designing improved investigations to develop novel varieties with high attributes. Therefore, this communication summarizes various defense strategies induced against HM stress and includes the function of metabolites (metabolomics), trace elements (ionomics), transcription factors (transcriptomics), and various stress-inducible proteins (proteomics) including the role of plant hormones.
The leaves of 22 woody and herbaceous plant species growing in urban ecosystems of Kalinigrad wer... more The leaves of 22 woody and herbaceous plant species growing in urban ecosystems of Kalinigrad were analyzed for the total contents of water-soluble antioxidants (TAC) and polyphenol contents. The soils of test plots were assayed for lead contents in the accumulative horizon. A significant excess over the background Pb level was revealed in soil samples from residential and industrial/utility areas (42% of the city territory), and TAC in plant tissues was found to decrease with an increase in Pb concentration in the soil. The role of polyphenols in forming the antioxidant potential of urban plants growing under conditions of technogenic soil pollution was evaluated. Based on cluster analysis of the water-soluble antioxidant and polyphenol accumulation patterns, the plants were classified into four groups. The results of this study may be used for comprehensive assessment of the resilience of urban plants to anthropogenic impact and improvement of the approaches and methods for monitoring industrial pollution in urban areas.
Heavy metals (HMs) exists in the environment in both forms as essential and non-essential. These ... more Heavy metals (HMs) exists in the environment in both forms as essential and non-essential. These HM ions enter in soil biota from various sources like natural and anthropogenic. Essential HMs such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) plays a beneficial role in plant growth and development. At optimum level these beneficial elements improves the plant's nutritional level and also several mechanisms essential for the normal growth and better yield of plants. The range of their optimality for land plants is varied. Plant uptake heavy metals as a soluble component or solubilized them by root exudates. While their presence in excess become toxic for plants that switches the plant's ability to uptake and accumulate other non-essential elements. The increased amount of HMs within the plant tissue displays direct and indirect toxic impacts. Such direct effects are the generation of oxidative stress which further aggravates inhibition of cytoplasmic enzymes and damage to cell structures. Although, indirect possession is the substitution of essential nutrients at plant's cation exchange sites. These ions readily influence role of various enzymes and proteins, arrest metabolism, and reveal phytotoxicity. On account of recent advancements on beneficial HMs ions Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: overview the sources of HMs in soils and their uptake and transportation mechanism, here we have discussed the role of metal transporters in transporting the essential metal ions from soil to plants. The role played by Co, Cu, Fe, Mn, Mo, Ni, and Zn at both low and high level on the plant growth and development and the mechanism to alleviate metal toxicity at high level have been also discussed. At the end, on concluding the article we have also discussed the future perspective in respect to beneficial HM ions interaction with plant at both levels.
Biochemistry & Pharmacology: Open Access, 2016
Heavy metals (HMs) contaminate the soil through various natural and anthropogenic resources and a... more Heavy metals (HMs) contaminate the soil through various natural and anthropogenic resources and are transported to the plant systems. These heavy metals are translocated within the plant system by the apoplast and symplast through various transporters such as HMAs, ZIP, ABC. HMs disturb plant metabolism, cause oxidative stress and nutrient dearth. Many researchers have applied exogenous minerals to alleviate these negative impacts caused by HMs. Minerals mitigate the HMAs induced negative impacts by the enhancement of biochemical reactions and physiological processes in plants. In the present article the role of exogenous mineral regulation under heavy metal toxicity is being discussed.
Abstract Aluminum (Al) precipitates in acidic soils having a pH < 5.5, in the form of conjugat... more Abstract Aluminum (Al) precipitates in acidic soils having a pH < 5.5, in the form of conjugated organic and inorganic ions. Al-containing minerals solubilized in the soil solution cause several negative impacts in plants when taken up along with other nutrients. Moreover, a micromolar concentration of Al present in the soil is enough to induce several irreversible toxicity symptoms such as the rapid and transient over-generation of reactive oxygen species (ROS) such as superoxide anion (O2•−), hydrogen peroxide (H2O2), and hydroxyl radical (•OH), resulting in oxidative bursts. In addition, significant reductions in water and nutrient uptake occur which imposes severe stress in the plants. However, some plants have developed Al-tolerance by stimulating the secretion of organic acids like citrate, malate, and oxalate, from plant roots. Genes responsible for encoding such organic acids, play a critical role in Al tolerance. Several transporters involved in Al resistance mechanisms are members of the Aluminum-activated Malate Transporter (ALMT), Multidrug and Toxic compound Extrusion (MATE), ATP-Binding Cassette (ABC), Natural resistance-associated macrophage protein (Nramp), and aquaporin gene families. Therefore, in the present review, the discussion of the global extension and probable cause of Al in the environment and mechanisms of Al toxicity in plants are followed by detailed emphasis on tolerance mechanisms. We have also identified and categorized the important transporters that secrete organic acids and outlined their role in Al stress tolerance mechanisms in crop plants. The information provided here will be helpful for efficient exploration of the available knowledge to develop Al tolerant crop varieties.
Flavonoids are characterized as the low molecular weight polyphenolic compounds universally distr... more Flavonoids are characterized as the low molecular weight polyphenolic compounds universally distributed in planta. They are a chemically varied group of secondary metabolites with a broad range of biological activity. The increasing amount of evidence has demonstrated the various physiological functions of flavonoids in stress response. In this paper, we provide a brief introduction to flavonoids’ biochemistry and biosynthesis. Then, we review the recent findings on the alternation of flavonoid content under different stress conditions to come up with an overall picture of the mechanism of involvement of flavonoids in plants’ response to various abiotic stresses. The participation of flavonoids in antioxidant systems, flavonoid-mediated response to different abiotic stresses, the involvement of flavonoids in stress signaling networks, and the physiological response of plants under stress conditions are discussed in this review. Moreover, molecular and genetic approaches to tailoring...
The dipotassium phosphate (K2HPO4) is a source of phosphorus (P), which is an essential micronutr... more The dipotassium phosphate (K2HPO4) is a source of phosphorus (P), which is an essential micronutrient for plant growth and reproduction and also acts as a stress alleviator against abiotic stresses. Therefore, it could also become a potential mineral to cope up with zinc oxide nanoparticles’ (ZnONPs) toxicity in crops. This study primarily includes synthesis, characterization and differential toxic impacts of ZnONPs on two crop plantsThis study includes synthesis, characterization and differential toxic impacts of ZnONPs on two crop plants, i.e. Triticum aestivum and Solanum lycopersicum, as well as assuage the toxic impacts of ZnONPs through nutrient management approach implied via supplementation of P. The growth and physiological changes under toxic doses of ZnONPs and ameliorative potential of P in crop plants were examined by analysing growth, intracellular Zn accumulation, photosynthetic pigment contents, the kinetics of photosystem II (PS II) photochemistry, root cell anatomy...
Abstract Small RNAs are single-stranded noncoding RNA molecules of ~20–30 nucleotides known to pl... more Abstract Small RNAs are single-stranded noncoding RNA molecules of ~20–30 nucleotides known to play a significant role in several cellular mechanisms. These small RNAs comprised small-interference RNAs (siRNAs), microRNAs (miRNAs), and PIWI (P element–induced wimpy testis)-interacting RNAs. The small RNAs regulate gene expression at the transcriptional and posttranscriptional level, and the whole mechanism of gene regulation by small RNAs is referred to as RNA interference. Among small RNAs, miRNAs and siRNAs are found in majority of eukaryotes, while piRNAs are found only in animals. miRNAs are an evolutionarily conserved group of ~22 nucleotides long-endogenous noncoding RNAs, which control the gene expressions, while posttranscriptionally via either transcript cleavage, translation repression, or both. It is becoming apparent that miRNAs assist various regulatory mechanisms such as developmental timing, host–pathogen interaction, cell differentiation, cell proliferation, apoptosis, as well as tumorigenesis. miRNA acts as a regulatory element and is modulated by various effectors such as single nucleotide polymorphism (SNP), miRNA editing, methylation, and circadian clock.
Nanomaterials in Plants, Algae, and Microorganisms
Objective: Since structural changes of adsorbed protein are necessary for cellular uptake of nano... more Objective: Since structural changes of adsorbed protein are necessary for cellular uptake of nanoparticles (NPs) it is of prime importance to know about structural changes of bovine serum albumin (BSA) when it interacts with CuO NPs-a potential new antitumor drug. Methods: CuO NPs prepared by sol-gel technique were characterized by x-ray diffraction (XRD) and tunneling electron microscope (TEM) techniques. The conformational changes induced by CuO NPs on BSA were studied by various spectroscopic techniques such as steady state and time-resolved fluorescence measurements. The changes in fluorescence emission parameters such as fluorescence intensity, fluorescence emission maximum and lifetimes of fluorescent residues in BSA were studied. Results: XRD analysis showed the average particle size as 32 nm. The TEM micrograph showed particles of different size varying from 10 to 45 nm. Fluorescence quenching was confirmed due to a decrease in fluorescence intensity of CuO NPs-BSA complex. The analysis of lifetime measurements indicated BSA contained two tryptophan (trp) residues that fluoresced in different environments. Static quenching mechanism was confirmed by time-resolved measurements when BSA interacted with CuO NPs. Conclusion: Minor structural changes of BSA protein were observed during the interaction studies.
In agriculture, abiotic stress is one of the critical issues impacting the crop productivity and ... more In agriculture, abiotic stress is one of the critical issues impacting the crop productivity and yield. Such stress factors lead to the generation of reactive oxygen species, membrane damage, and other plant metabolic activities. To neutralize the harmful effects of abiotic stress, several strategies have been employed that include the utilization of nanomaterials. Nanomaterials are now gaining attention worldwide to protect plant growth against abiotic stresses such as drought, salinity, heavy metals, extreme temperatures, flooding, etc. However, their behavior is significantly impacted by the dose in which they are being used in agriculture. Furthermore, the action of nanomaterials in plants under various stresses still require understanding. Hence, with this background, the present review envisages to highlight beneficial role of nanomaterials in plants, their mode of action, and their mechanism in overcoming various abiotic stresses. It also emphasizes upon antioxidant activitie...
Abstract Heavy metal (HM) pollution in environment occurs due to their release from natural resou... more Abstract Heavy metal (HM) pollution in environment occurs due to their release from natural resources, such as rocks, ore minerals, volcanoes, weathering, and various anthropogenic activities like urban advancement, electricity generation, mining, and refinery industries. HMs are transition metals, which possess atomic mass more than 0.002 kg, weight about 5 N/m3, and density greater than 5 g/cm3. These metals are categorized as essential, such as copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), iron (Fe), cobalt (Co), molybdenum (Mo), selenium (Se), and nonessential metals. Essential HMs play vital regulatory roles in several cellular reactions, including electron transfer, in enzyme activation, in redox reaction, as well as in the synthesis of pigments, whereas nonessential metals, such as chromium (Cr), cadmium (Cd), lead (Pb), silver (Ag), mercury (Hg), and arsenic (As), have no role in any biological reaction, thus cause toxic impacts even at low concentrations by competing with crucial elements at protein-binding sites. Although when the amount of these metals increases beyond the optimum point, they cause toxicity in plants, by decreasing growth, causing soil quality deterioration and by affecting the yield. Toxicity of HMs depends on the concentration, reactivity, as well as on their oxidation capacity. Crops are more susceptible to these HMs, as they transport HMs to organisms through the food chain. HM-stressed plant shows alteration in cellular mechanisms and gene regulation. These HMs generate free radicals in cells, which further cause toxicity in plants. Nonessential metals deliberate various physiological reactions, through the alteration in biomolecules and in regulatory proteins or by replacement of crucial metals, therefore disturb the integrity of biomolecules and affects antioxidant defense system by generating reactive oxygen species. Plant acquires several defense approaches to safeguard against metal toxicity; such processes include sequestration, compartmentalization, exclusion, and inactivation by the secretion of organic ligands. Beside this, plants also induce antioxidant system as well as maintain the metal homeostasis by restricting the metal bioavailability.
Journal of emerging technologies and innovative research, 2020
Silver nanoparticles (AgNPs) are used in several commercial products, medical and diagnostic trea... more Silver nanoparticles (AgNPs) are used in several commercial products, medical and diagnostic treatments, and as nano-pesticide and nano-herbicide. On release, it contaminates the environment and ultimately reaches the agriculture field, causes an alteration in the plant growth and development, whereas their negatives impacts could be restored by the exogenous application of indole-3-acetic acid (IAA). Therefore, the present study has been carried out to examine the potential role of IAA on the toxicity of AgNPs in Oryza sativa seedlings. AgNPs at both doses (200 and 500 μM) showed a remarkable decline in growth, photosynthetic pigments, and protein content. AgNPs also negatively affected the kinetics of photosystem II (PS II) photochemistry that leads to oxidative stress as confirmed by invitro and in-vivo visualization of superoxide radicle (SOR) and hydrogen peroxide (H2O2) that ultimately cause cell death. While the addition of IAA along with AgNPs mitigates the toxicity by incre...
Copper oxide nanoparticles (CuONPs) toxicity has greatly affected the environment and particularl... more Copper oxide nanoparticles (CuONPs) toxicity has greatly affected the environment and particularly plants. It causes rapid changes in plant morphology and physiology; however, the changes can be restored via exogenous supplementation of Calcium (Ca). Thus, the present work has been undertaken to elucidate the impacts of Ca supplementation on reducing the CuONPs toxicity in S. lycopersicum. CuONPs at both the doses (500 and 1000 μM) showed significant reduction in growth, protein content, photosynthetic pigments, PS II photochemistry, contrastingly the reactive oxygen species (SOR and H2O2) were significantly raised as confirmed by invitro and in-vivo visualization of SOR and H2O2 that eventually leads to cell death as evidenced. Now days the nutrient management techniques have been widely used for the release of toxic effects caused by the pollutants in plants. In this study, the toxicity alleviation is achieved by exogenous application of calcium (Ca). Ca is a macronutrient that ac...
Histochemistry is an essential analytical tool interfacing extensively with plant science. The li... more Histochemistry is an essential analytical tool interfacing extensively with plant science. The literature is indeed constellated with examples showing its use to decipher specific physiological and developmental processes, as well as to study plant cell structures. Plant cell structures are translucent unless they are stained. Histochemistry allows the identification and localization, at the cellular level, of biomolecules and organelles in different types of cells and tissues, based on the use of specific staining reactions and imaging. Histochemical techniques are also widely used for the in vivo localization of promoters in specific tissues, as well as to identify specific cell wall components such as lignin and polysaccharides. Histochemistry also enables the study of plant reactions to environmental constraints, e.g. the production of reactive oxygen species (ROS) can be traced by applying histochemical staining techniques. The possibility of detecting ROS and localizing them a...
The action of nanoparticles is increasingly being studied in recent years to minimize their toxic... more The action of nanoparticles is increasingly being studied in recent years to minimize their toxic impacts. Besides this, efforts are also being made to minimize their toxicity in crop plants by using various chemicals, i.e. nutrients, donors of signalling molecules, plant hormones, etc. However, associated alleviatory mechanisms are still not well known. Therefore, in the present study, we have investigated the toxicity of CuONPs and its mitigation by exogenously applied calcium (Ca). The focus was on whether indole-3-acetic acid (IAA) or endogenous nitric oxide (NO) has any role in accomplishing this task. CuONPs declined wheat growth due to increased accumulation of Cu and oxidative stress markers such as superoxide radicals, hydrogen peroxide and lipid peroxidation (malondialdehyde) and it was also accompanied by a decline in endogenous NO. CuONPs also altered the redox status of ascorbate and glutathione by inhibiting the activity of their regenerating enzymes. This collectively leads to cell death in wheat seedlings. However, exogenous supplementation of Ca mitigated toxic effects of CuONPs by reducing the excess accumulation of Cu, which caused remarkable enhancement in growth, protein contents, photosynthetic pigments, and endogenous nitric oxide; altogether protecting wheat roots from cell death. Interestingly, addition of 2,3,5-triiodobenzoic acid (TIBA) further increased CuONPs toxicity even in the presence of Ca, but the addition of IAA rescued this effect of TIBA. These results clearly show that Ca mitigates CuONPs toxicity in wheat seedlings by involving IAA. Further, the results also showed that endogenous NO has a positive and indispensable role in Ca-mediated mitigation of CuONPs toxicity in wheat seedlings. This article is protected by copyright. All rights reserved.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Heavy metal (HMs) pollution is regarded as one of the major concerns for soil and water, causing ... more Heavy metal (HMs) pollution is regarded as one of the major concerns for soil and water, causing varieties of toxic and stress effects on plants and ecosystems. It has become one of the important limiting factors to crop productivity and quality. Due to an ever-increasing population growth and food demands, this situation has further worsened. Rice, a leading staple food crop that feeds more than 50% populations of the world, is constantly affected by abiotic stressors including HMs. In most of the countries, a major source of HM intake by humans is the rice grain produced through the paddy soils contaminated with HMs such as As, Al, Cu, Cr, Cd, Pb, Hg, Mn, Se, and Zn. Thus, gradual agglomeration of HMs in rice grains and their subsequent transfer to the food chain is a major menace to agriculture and human health. In recent years, several studies examined the impact of HMs toxicity on rice at multiple levels: molecular, biochemical, physiological, cellular and tissue, and demonstrated a correlation between HMs toxicity and the decreasing trend in rice productivity. Therefore, it is necessary to understand the interaction of HMs with rice crop spanning from the cell to whole plant level and devise appropriate effective means to alleviate these stress responses. This review focuses on tracing the pathways involved in stress responses and stress tolerance mechanisms displayed by different varieties of rice. However, it is essential to uncover the mechanisms related to stress responses in rice for designing improved investigations to develop novel varieties with high attributes. Therefore, this communication summarizes various defense strategies induced against HM stress and includes the function of metabolites (metabolomics), trace elements (ionomics), transcription factors (transcriptomics), and various stress-inducible proteins (proteomics) including the role of plant hormones.
The leaves of 22 woody and herbaceous plant species growing in urban ecosystems of Kalinigrad wer... more The leaves of 22 woody and herbaceous plant species growing in urban ecosystems of Kalinigrad were analyzed for the total contents of water-soluble antioxidants (TAC) and polyphenol contents. The soils of test plots were assayed for lead contents in the accumulative horizon. A significant excess over the background Pb level was revealed in soil samples from residential and industrial/utility areas (42% of the city territory), and TAC in plant tissues was found to decrease with an increase in Pb concentration in the soil. The role of polyphenols in forming the antioxidant potential of urban plants growing under conditions of technogenic soil pollution was evaluated. Based on cluster analysis of the water-soluble antioxidant and polyphenol accumulation patterns, the plants were classified into four groups. The results of this study may be used for comprehensive assessment of the resilience of urban plants to anthropogenic impact and improvement of the approaches and methods for monitoring industrial pollution in urban areas.
Heavy metals (HMs) exists in the environment in both forms as essential and non-essential. These ... more Heavy metals (HMs) exists in the environment in both forms as essential and non-essential. These HM ions enter in soil biota from various sources like natural and anthropogenic. Essential HMs such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) plays a beneficial role in plant growth and development. At optimum level these beneficial elements improves the plant's nutritional level and also several mechanisms essential for the normal growth and better yield of plants. The range of their optimality for land plants is varied. Plant uptake heavy metals as a soluble component or solubilized them by root exudates. While their presence in excess become toxic for plants that switches the plant's ability to uptake and accumulate other non-essential elements. The increased amount of HMs within the plant tissue displays direct and indirect toxic impacts. Such direct effects are the generation of oxidative stress which further aggravates inhibition of cytoplasmic enzymes and damage to cell structures. Although, indirect possession is the substitution of essential nutrients at plant's cation exchange sites. These ions readily influence role of various enzymes and proteins, arrest metabolism, and reveal phytotoxicity. On account of recent advancements on beneficial HMs ions Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: overview the sources of HMs in soils and their uptake and transportation mechanism, here we have discussed the role of metal transporters in transporting the essential metal ions from soil to plants. The role played by Co, Cu, Fe, Mn, Mo, Ni, and Zn at both low and high level on the plant growth and development and the mechanism to alleviate metal toxicity at high level have been also discussed. At the end, on concluding the article we have also discussed the future perspective in respect to beneficial HM ions interaction with plant at both levels.
Biochemistry & Pharmacology: Open Access, 2016
Heavy metals (HMs) contaminate the soil through various natural and anthropogenic resources and a... more Heavy metals (HMs) contaminate the soil through various natural and anthropogenic resources and are transported to the plant systems. These heavy metals are translocated within the plant system by the apoplast and symplast through various transporters such as HMAs, ZIP, ABC. HMs disturb plant metabolism, cause oxidative stress and nutrient dearth. Many researchers have applied exogenous minerals to alleviate these negative impacts caused by HMs. Minerals mitigate the HMAs induced negative impacts by the enhancement of biochemical reactions and physiological processes in plants. In the present article the role of exogenous mineral regulation under heavy metal toxicity is being discussed.
Abstract Aluminum (Al) precipitates in acidic soils having a pH < 5.5, in the form of conjugat... more Abstract Aluminum (Al) precipitates in acidic soils having a pH < 5.5, in the form of conjugated organic and inorganic ions. Al-containing minerals solubilized in the soil solution cause several negative impacts in plants when taken up along with other nutrients. Moreover, a micromolar concentration of Al present in the soil is enough to induce several irreversible toxicity symptoms such as the rapid and transient over-generation of reactive oxygen species (ROS) such as superoxide anion (O2•−), hydrogen peroxide (H2O2), and hydroxyl radical (•OH), resulting in oxidative bursts. In addition, significant reductions in water and nutrient uptake occur which imposes severe stress in the plants. However, some plants have developed Al-tolerance by stimulating the secretion of organic acids like citrate, malate, and oxalate, from plant roots. Genes responsible for encoding such organic acids, play a critical role in Al tolerance. Several transporters involved in Al resistance mechanisms are members of the Aluminum-activated Malate Transporter (ALMT), Multidrug and Toxic compound Extrusion (MATE), ATP-Binding Cassette (ABC), Natural resistance-associated macrophage protein (Nramp), and aquaporin gene families. Therefore, in the present review, the discussion of the global extension and probable cause of Al in the environment and mechanisms of Al toxicity in plants are followed by detailed emphasis on tolerance mechanisms. We have also identified and categorized the important transporters that secrete organic acids and outlined their role in Al stress tolerance mechanisms in crop plants. The information provided here will be helpful for efficient exploration of the available knowledge to develop Al tolerant crop varieties.
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Papers by Namira Arif