Comparative effect of calcium and EDTA on arsenic uptake and physiological attributes of Pisum sativum.

In this study, we determined the effect of ethylenediaminetetraacetic acid (EDTA) and calcium (Ca) on arsenic (As) uptake and toxicity to Pisum sativum. Plants were treated with three levels of As (25, 125, 250 µM) in the presence and absence of three levels of Ca (1, 5, 10 mM) and EDTA (25, 125, 250 µM). Exposure to As caused an overproduction of hydrogen peroxide (H2O2) in roots and leaves, which induced lipid peroxidation and decreased pigment contents. Application of both Ca and EDTA significantly reduced As accumulation by pea, Ca being more effective in reducing As accumulation. Both Ca and EDTA enhanced As-induced H2O2 production, but reduced lipid peroxidation. In the case of pigment contents, EDTA significantly reduced pigment contents, whereas Ca significantly enhanced pigment contents compared to As alone. The effect of As treatment in the presence and absence of EDTA and Ca was more pronounced in younger leaves compared to older leaves. The effect of amendments varied greatly with their applied levels, as well as type and age of plant organs. Importantly, due to possible precipitation of Ca-As compounds, the soils with higher levels of Ca ions are likely to be less prone to food chain contamination

Chromium speciation, bioavailability, uptake, toxicity and detoxification in soil-plant system: A review

Chromium (Cr) is a potentially toxic heavy metal which does not have any essential metabolic function in plants. Various past and recent studies highlight the biogeochemistry of Cr in the soil-plant system. This review traces a plausible link among Cr speciation, bioavailability, phytouptake, phytotoxicity and detoxification based on available data, especially published from 2010 to 2016. Chromium occurs in different chemical forms (primarily as chromite (Cr(III)) and chromate (Cr(VI)) in soil which vary markedly in term of their biogeochemical behavior. Chromium behavior in soil, its soil-plant transfer and accumulation in different plant parts vary with its chemical form, plant type and soil physico-chemical properties. Soil microbial community plays a key role in governing Cr speciation and behavior in soil. Chromium does not have any specific transporter for its uptake by plants and it primarily enters the plants through specific and non-specific channels of essential ions. Chromium accumulates predominantly in plant root tissues with very limited translocation to shoots. Inside plants, Cr provokes numerous deleterious effects to several physiological, morphological, and biochemical processes. Chromium induces phytotoxicity by interfering plant growth, nutrient uptake and photosynthesis, inducing enhanced generation of reactive oxygen species, causing lipid peroxidation and altering the antioxidant activities. Plants tolerate Cr toxicity via various defense mechanisms such as complexation by organic ligands, compartmentation into the vacuole, and scavenging ROS via antioxidative enzymes. Consumption of Cr-contaminated-food can cause human health risks by inducing severe clinical conditions. Therefore, there is a dire need to monitor biogeochemical behavior of Cr in soil-plant system

A comparative study to evaluate efficiency of EDTA and calcium in alleviating arsenic toxicity to germinating and young Vicia faba L. seedlings

Purpose: This study delineated the effect of calcium (Ca) and ethylenediaminetetraacetic acid (EDTA) addition on arsenic (As) accumulation and physiological attributes of Vicia faba L. Materials and methods: Two separate experiments were performed. In the first experiment, V. faba seedlings, grown under hydroponic conditions, were exposed to three levels of As (25, 125 and 250 μM) in the presence and absence of three levels of EDTA (25, 125, 250 μM) and calcium (CaCl2: 1, 5 and 10 mM). The effect of EDTA and Ca on As accumulation and physiological attributes of V. faba was assessed by determining As contents in roots and shoot, chlorophyll contents, H2O2 contents, and lipid peroxidation in young and old leaves. In the second experiment, V. faba seeds were grown in Ascontaminated sand culture using the same treatment plan. Results and discussion: The accumulation and toxicity of As to V. faba plants increased with increasing As levels in nutrient solution. Arsenic exposure enhanced the production of reactive oxygen species (ROS) in both roots and leaves, which resulted in lipid peroxidation and decreased chlorophyll contents. The presence of both EDTA and Ca, in general, significantly decreased As accumulation by V. faba seedlings, Ca being more effective than EDTA. Both the amendments decreased As-induced reactive oxygen species (ROS) production and lipid peroxidation. In the case of chlorophyll contents, EDTA significantly decreased chlorophyll contents, while Ca significantly increased chlorophyll contents compared to As. The effect of all the treatments was more pronounced in roots than leaves and in young leaves compared to old leaves. Conclusions: It is proposed that EDTA and Ca greatly affect As accumulation and toxicity to V. faba, and the effect varies greatly with their applied levels as well as type and age of plant organs. The germinating seedlings of V. faba may be preferred for risk assessment studies, while transplanting 1-week-old V. faba seedlings to As-contaminated soils can decrease its toxicity

Comparative effect of organic amendments on physio-biochemical traits of young and old bean leaves grown under cadmium stress : a multivariate analysis

The current study investigated the influence of organic amendments on cadmium (Cd) uptake and its effects on biochemical attributes of young and old leaves of bean. Bean seedlings were exposed to two levels of Cd (25 and 100 μM) in the presence and absence of different levels of ethylenediaminetetraacetic acid (EDTA) and citric acid (CA). An increase in Cd concentration in growth medium significantly enhanced Cd accumulation in bean roots and shoot. Cadmium stress increased the production of H2O2 which resulted in lipid peroxidation and decreased chlorophyll contents. The presence of organic amendments significantly affected Cd accumulation and toxicity to bean plants. Application of EDTA alleviated Cd toxicity in terms of chlorophyll contents, H2O2 contents, and lipid peroxidation possibly by chelating toxic Cd ions, and as such forming Cd-EDTA complexes. The presence of CA decreased Cd toxicity by decreasing its uptake. The biochemical responses (H2O2 contents, lipid peroxidation, and chlorophyll contents) of bean plants were more severely affected by Cd treatments in old leaves compared to young leaves. This study shows that the effect of CA and EDTA on biochemical behavior of Cd varies greatly with applied levels of Cd and amendments as well as the age of leaves. Based on the results, it is proposed that the presence of organic amendments can greatly affect biogeochemical behavior of Cd in the soil-plant system (ecosystem)

Comparative effect of organic amendments on physio-biochemical traits of young and old bean leaves grown under cadmium stress : a multivariate analysis

The current study investigated the influence of organic amendments on cadmium (Cd) uptake and its effects on biochemical attributes of young and old leaves of bean. Bean seedlings were exposed to two levels of Cd (25 and 100 μM) in the presence and absence of different levels of ethylenediaminetetraacetic acid (EDTA) and citric acid (CA). An increase in Cd concentration in growth medium significantly enhanced Cd accumulation in bean roots and shoot. Cadmium stress increased the production of H2O2 which resulted in lipid peroxidation and decreased chlorophyll contents. The presence of organic amendments significantly affected Cd accumulation and toxicity to bean plants. Application of EDTA alleviated Cd toxicity in terms of chlorophyll contents, H2O2 contents, and lipid peroxidation possibly by chelating toxic Cd ions, and as such forming Cd-EDTA complexes. The presence of CA decreased Cd toxicity by decreasing its uptake. The biochemical responses (H2O2 contents, lipid peroxidation, and chlorophyll contents) of bean plants were more severely affected by Cd treatments in old leaves compared to young leaves. This study shows that the effect of CA and EDTA on biochemical behavior of Cd varies greatly with applied levels of Cd and amendments as well as the age of leaves. Based on the results, it is proposed that the presence of organic amendments can greatly affect biogeochemical behavior of Cd in the soil-plant system (ecosystem)

A multivariate analysis of health risk assessment, phytoremediation potential, and biochemical attributes of Spinacia oleracea exposed to cadmium in the presence of organic amendments under hydroponic conditions

Cadmium (Cd) phytoremediation potential and its accumulation in edible and nonedible plant tissues is the function of various biochemical processes taking place inside plants. This study assessed the impact of organic ligands on Cd phyto uptake and different biophysiochemical processes of Spinacia oleracea L., and associated health hazards. Plants were exposed to Cd alone and chelated with citric acid (CA) and ethylenediaminetetraacetic acid (EDTA). Results revealed that the effect of Cd on lipid peroxidation, H2O2 production and pigment contents varied greatly with its applied level and the type of organic ligand. Moreover, the effect was more prominent in root tissues than leaf tissues and for high concentrations of Cd and organic ligands. Cadmium accumulation increased by 90 and 74% in roots and leaves, respectively, with increasing Cd levels (25–100 µM). Cadmium exposure at high levels caused lipid peroxidation in roots only. Application of both CA and EDTA slightly diminished Cd toxicity with respect to pigment contents, lipid peroxidation and hydrogen peroxide (H2O2) contents. Hazard quotient (HQ) of Cd was \u3c1.00 for all the treatments. Under nonlinear effect of treatments, multivariate analysis can be an effective tool to trace overall effects/trends