Toxics

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4 pages, 193 KiB

Open AccessEditorial

Heavy Metal Toxicity Effects on Plants

by Ilektra Sperdouli

Toxics 2022, 10(12), 715; https://doi.org/10.3390/toxics10120715 - 23 Nov 2022

Cited by 8 | Viewed by 3820

Abstract

Although heavy metals are naturally present in the soil, geologic and anthropogenic activities increase the concentration of these elements to amounts that are harmful to plants [...] Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

Research

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14 pages, 1843 KiB

Open AccessArticle

Tolerance and Heavy Metal Accumulation Characteristics of Sasa argenteostriata (Regel) E.G. Camus under Zinc Single Stress and Combined Lead–Zinc Stress

by Jiarong Liao, Ningfeng Li, Yixiong Yang, Jing Yang, Yuan Tian, Zhenghua Luo and Mingyan Jiang

Toxics 2022, 10(8), 450; https://doi.org/10.3390/toxics10080450 - 04 Aug 2022

Cited by 4 | Viewed by 1265

Abstract

Sasa argenteostriata (Regel) E.G. Camus is a gramineous plant with the potential for phytoremediation. In this study, we aimed to determine its tolerance to zinc stress and combined lead–zinc stress and the effect of zinc on its absorption and accumulation characteristics of lead. [...] Read more.

Sasa argenteostriata (Regel) E.G. Camus is a gramineous plant with the potential for phytoremediation. In this study, we aimed to determine its tolerance to zinc stress and combined lead–zinc stress and the effect of zinc on its absorption and accumulation characteristics of lead. The results showed that S. argenteostriata had good tolerance to zinc stress, and S. argenteostriata was not significantly damaged when the zinc stress concentration was 600 mg/L. Under both zinc stress and combined lead–zinc stress, the root was the main organ that accumulated heavy metals in S. argenteostriata. The presence of zinc promoted the absorption of lead by the root of S. argenteostriata, and the lead content in the root under PZ1, PZ2, PZ3 and PZ4 treatments was 2.15, 4.31, 4.47 and 6.01 times that of PZ0 on the 20 days. In the combined lead–zinc stress treatments, the toxicity of heavy metals to S. argenteostriata was mainly caused by lead. Under high concentrations of combined lead–zinc stress (PZ4), the proportion of zinc in the leaf of S. argenteostriata on the 20 days increased, which was used as a tolerance strategy to alleviate the toxicity of lead. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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17 pages, 3502 KiB

Open AccessEditor’s ChoiceArticle

Alleviation of Ammonium Toxicity in Salvia splendens ‘Vista Red’ with Silicon Supplementation

by Jinnan Song, Jingli Yang and Byoung Ryong Jeong

Toxics 2022, 10(8), 446; https://doi.org/10.3390/toxics10080446 - 03 Aug 2022

Cited by 7 | Viewed by 1934

Abstract

Ammonium (NH₄⁺) toxicity seriously hampers the yield and quality of salvia plants because most varieties or sub-species are highly sensitive to NH₄⁺. Silicon (Si) is an alternative that is used to minimize these disturbances and maintain better [...] Read more.

Ammonium (NH₄⁺) toxicity seriously hampers the yield and quality of salvia plants because most varieties or sub-species are highly sensitive to NH₄⁺. Silicon (Si) is an alternative that is used to minimize these disturbances and maintain better growth under NH₄⁺ toxicity. Nevertheless, the mitigatory effects of Si on NH₄⁺-stressed salvia are unknown. Therefore, this study was carried out to determine how Si assists to alleviate the NH₄⁺ toxicity degree in salvia. To this end, salvia plants were cultivated in a controlled environment supplied with a constant N (nitrogen) level (13 meq·L⁻¹) in the form of three NH₄⁺:NO₃⁻ ratios (0:100, 50:50, 100:0), each with (1.0 meq·L⁻¹) or without Si. Physiological disorders and typical NH₄⁺ toxicity symptoms, as well as interrupted photosynthesis, were observed in the 100% NH₄⁺-treated plants. Furthermore, cation uptake inhibition and oxidative damage were also imposed by the 100% NH₄⁺ supply. In contrast, in the presence of Si, the NH₄⁺ toxicity degree was attenuated and plant growth was ensured. Accordingly, the NH₄⁺ toxicity appearance ratio decreased significantly. Furthermore, Si-treated plants showed an ameliorated photosynthetic ability, elevated internal K and Ca levels, and enhanced antioxidative capacity, as reflected by improved major antioxidant enzyme activities, as well as diminished accumulation of ROS (reactive oxygen species) and MDA (malondialdehyde). Our findings enlightened the agronomic importance of additional Si to nutrient solutions, especially pertaining to bedding plants at risk of NH₄⁺ toxicity. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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20 pages, 6468 KiB

Open AccessArticle

Combine Effect of ZnO NPs and Bacteria on Protein and Gene’s Expression Profile of Rice (Oryza sativa L.) Plant

by Nazneen Akhtar, Sehresh Khan, Muhammad Jamil, Shafiq Ur Rehman, Zia Ur Rehman and Eui Shik Rha

Toxics 2022, 10(6), 305; https://doi.org/10.3390/toxics10060305 - 03 Jun 2022

Cited by 8 | Viewed by 2106

Abstract

Heavy metal (HM) emissions have increased due to the impact of rising urbanization and anthropogenic activity, affecting different parts of the environment. The goal of this study is to investigate the combined effect of ZnO NPs and bacteria treatment on protein and gene [...] Read more.

Heavy metal (HM) emissions have increased due to the impact of rising urbanization and anthropogenic activity, affecting different parts of the environment. The goal of this study is to investigate the combined effect of ZnO NPs and bacteria treatment on protein and gene expression profiles of rice plants that are grown in HMs-polluted water. Seeds were primed with Bacillus spp. (Bacillus cereus and Lysinibacillus macroides) before being cultured in Hoagland media containing ZnO NPs (5 and 10 mg/L) and HMs-contaminated water from the Hayatabad industrial estate (HIE), Peshawar, Pakistan. The results revealed that the maximum nitrogen and protein content was observed in the root, shoot, and leaf of the plant grown by combining bacteria-ZnO NPs treatment under HMs stress as compared with plant grown without or with individual treatments of ZnO NPs and bacteria. Furthermore, protein expression analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) revealed that plants that were grown in HMs-polluted water were found to be affected in contaminated water, however the combined effect of bacteria-ZnO NPs reported the more dense protein profile as compared with their individual treatments. Subsequently, plants that were grown in HMs-polluted water have the highest expression levels of stress-induced genes such as myeloblastosis (Myb), zinc-finger protein (Zat-12), and ascorbate peroxidase (Apx) while the combined effect revealed minimum expression as compared with individual treatments. It is concluded that the combined effect of ZnO NPs and bacteria lowered the stress-induced gene expression while it increased the nitrogen-protein content and protein expression in plant grown under HMs stress. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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16 pages, 3312 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Excess Zinc Supply Reduces Cadmium Uptake and Mitigates Cadmium Toxicity Effects on Chloroplast Structure, Oxidative Stress, and Photosystem II Photochemical Efficiency in Salvia sclarea Plants

by Ilektra Sperdouli, Ioannis-Dimosthenis S. Adamakis, Anelia Dobrikova, Emilia Apostolova, Anetta Hanć and Michael Moustakas

Toxics 2022, 10(1), 36; https://doi.org/10.3390/toxics10010036 - 12 Jan 2022

Cited by 29 | Viewed by 3756

Abstract

Salvia sclarea L. is a Cd²⁺ tolerant medicinal herb with antifungal and antimicrobial properties cultivated for its pharmacological properties. However, accumulation of high Cd²⁺ content in its tissues increases the adverse health effects of Cd²⁺ in humans. Therefore, there is [...] Read more.

Salvia sclarea L. is a Cd²⁺ tolerant medicinal herb with antifungal and antimicrobial properties cultivated for its pharmacological properties. However, accumulation of high Cd²⁺ content in its tissues increases the adverse health effects of Cd²⁺ in humans. Therefore, there is a serious demand to lower human Cd²⁺ intake. The purpose of our study was to evaluate the mitigative role of excess Zn²⁺ supply to Cd²⁺ uptake/translocation and toxicity in clary sage. Salvia plants were treated with excess Cd²⁺ (100 μM CdSO₄) alone, and in combination with Zn²⁺ (900 μM ZnSO₄), in modified Hoagland nutrient solution. The results demonstrate that S. sclarea plants exposed to Cd²⁺ toxicity accumulated a significant amount of Cd²⁺ in their tissues, with higher concentrations in roots than in leaves. Cadmium exposure enhanced total Zn²⁺ uptake but also decreased its translocation to leaves. The accumulated Cd²⁺ led to a substantial decrease in photosystem II (PSII) photochemistry and disrupted the chloroplast ultrastructure, which coincided with an increased lipid peroxidation. Zinc application decreased Cd²⁺ uptake and translocation to leaves, while it mitigated oxidative stress, restoring chloroplast ultrastructure. Excess Zn²⁺ ameliorated the adverse effects of Cd²⁺ on PSII photochemistry, increasing the fraction of energy used for photochemistry (Φ_PSII) and restoring PSII redox state and maximum PSII efficiency (Fv/Fm), while decreasing excess excitation energy at PSII (EXC). We conclude that excess Zn²⁺ application eliminated the adverse effects of Cd²⁺ toxicity, reducing Cd²⁺ uptake and translocation and restoring chloroplast ultrastructure and PSII photochemical efficiency. Thus, excess Zn²⁺ application can be used as an important method for low Cd²⁺-accumulating crops, limiting Cd²⁺ entry into the food chain. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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10 pages, 1650 KiB

Open AccessCommunication

Lowering the Toxicity of Cd to Theobroma cacao Using Soil Amendments Based on Commercial Charcoal and Lime

by Carla Calixta Calva Jiménez, Liliana Valentina Pinedo Fernández and Cristiano E. Rodrigues Reis

Toxics 2022, 10(1), 15; https://doi.org/10.3390/toxics10010015 - 04 Jan 2022

Cited by 1 | Viewed by 1473

Abstract

Carbonaceous and calcareous materials are commonly used as amendments to decrease the Cd mobility in contaminated soils. This study evaluated the effect of amendments applied to cocoa seedlings in the greenhouse, considering the mobilization of soil cadmium toward the seedlings as the main [...] Read more.

Carbonaceous and calcareous materials are commonly used as amendments to decrease the Cd mobility in contaminated soils. This study evaluated the effect of amendments applied to cocoa seedlings in the greenhouse, considering the mobilization of soil cadmium toward the seedlings as the main response. The experimental conditions considered soil artificially contaminated with Cd at a concentration of 50 mg Cd kg⁻¹ and applications of amendments in different treatments with the presence of charcoal dust and calcium carbonate. The charcoal was characterized by microscopy and by adsorption tests, and it proved to be a material with macropores, with a maximum capacity of 8.06 mg Cd g⁻¹ and favorable kinetic behavior according to the adjustment of the data obtained to the pseudo-second-order model. The results also showed that the application of liming decreased the mobility of Cd toward the seedlings, with the liming combined with charcoal leading to the absence of Cd in the cocoa seedlings, considering a residual concentration of Cd in the soil of 35 mg Cd kg⁻¹. The results, although limited to a small scale, demonstrated the possibility of applying low-cost and easy-to-handle amendments for the control of Cd in cocoa plantations. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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9 pages, 262 KiB

Open AccessFeature PaperArticle

Biochar Amendment Reduces the Availability of Pb in the Soil and Its Uptake in Lettuce

by Andrea Vannini, Elisabetta Bianchi, Diego Avi, Nicole Damaggio, Luigi Antonello Di Lella, Francesco Nannoni, Giuseppe Protano and Stefano Loppi

Toxics 2021, 9(10), 268; https://doi.org/10.3390/toxics9100268 - 15 Oct 2021

Cited by 9 | Viewed by 2068

Abstract

The aim of this study was to investigate the ability of biochar amendment to reduce the availability of Pb in the soil and its uptake in lettuce (Lactuca sativa L. var. adela). Seedlings of lettuce were cultivated in Pb-contaminated soils, both [...] Read more.

The aim of this study was to investigate the ability of biochar amendment to reduce the availability of Pb in the soil and its uptake in lettuce (Lactuca sativa L. var. adela). Seedlings of lettuce were cultivated in Pb-contaminated soils, both with and without 5% biochar (w/w), as well as in a simplified soilless system (hydroponics) at the ecologically relevant Pb concentration of 100 µM, both with and without 1% biochar. Soils amended with biochar resulted in a ca. 50% reduction of the extractable (bioavailable) fraction of Pb, limiting the accumulation of this toxic element in the leaves of lettuce by ca. 50%. A similar behavior was observed for lettuce plants grown hydroponically, even with a much higher reduction of Pb uptake (ca. 80%). Increased cation exchange capacity and pH were likely the main factors limiting the bioavailability of Pb in the soil. Complexation with functional groups and precipitation/co-precipitation both on the biochar surface and in soil aggregates were likely the main mechanisms immobilizing this element. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

11 pages, 1252 KiB

Open AccessArticle

Growth and Antioxidant Responses in Iron-Biofortified Lentil under Cadmium Stress

by Ruchi Bansal, Swati Priya, Harsh Kumar Dikshit, Sherry Rachel Jacob, Mahesh Rao, Ram Swaroop Bana, Jyoti Kumari, Kuldeep Tripathi, Ashok Kumar, Shiv Kumar and Kadambot H. M. Siddique

Toxics 2021, 9(8), 182; https://doi.org/10.3390/toxics9080182 - 31 Jul 2021

Cited by 11 | Viewed by 2826

Abstract

Cadmium (Cd) is a hazardous heavy metal, toxic to our ecosystem even at low concentrations. Cd stress negatively affects plant growth and development by triggering oxidative stress. Limited information is available on the role of iron (Fe) in ameliorating Cd stress tolerance in [...] Read more.

Cadmium (Cd) is a hazardous heavy metal, toxic to our ecosystem even at low concentrations. Cd stress negatively affects plant growth and development by triggering oxidative stress. Limited information is available on the role of iron (Fe) in ameliorating Cd stress tolerance in legumes. This study assessed the effect of Cd stress in two lentil (Lens culinaris Medik.) varieties differing in seed Fe concentration (L4717 (Fe-biofortified) and JL3) under controlled conditions. Six biochemical traits, five growth parameters, and Cd uptake were recorded at the seedling stage (21 days after sowing) in the studied genotypes grown under controlled conditions at two levels (100 μM and 200 μM) of cadmium chloride (CdCl₂). The studied traits revealed significant genotype, treatment, and genotype × treatment interactions. Cd-induced oxidative damage led to the accumulation of hydrogen peroxide (H₂O₂) and malondialdehyde in both genotypes. JL3 accumulated 77.1% more H₂O₂ and 75% more lipid peroxidation products than L4717 at the high Cd level. Antioxidant enzyme activities increased in response to Cd stress, with significant genotype, treatment, and genotype × treatment interactions (p < 0.01). L4717 had remarkably higher catalase (40.5%), peroxidase (43.9%), superoxide dismutase (31.7%), and glutathione reductase (47.3%) activities than JL3 under high Cd conditions. In addition, L4717 sustained better growth in terms of fresh weight and dry weight than JL3 under stress. JL3 exhibited high Cd uptake (14.87 mg g⁻¹ fresh weight) compared to L4717 (7.32 mg g⁻¹ fresh weight). The study concluded that the Fe-biofortified lentil genotype L4717 exhibited Cd tolerance by inciting an efficient antioxidative response to Cd toxicity. Further studies are required to elucidate the possibility of seed Fe content as a surrogacy trait for Cd tolerance. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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29 pages, 4503 KiB

Open AccessArticle

Assessment of the Suitability of Melilotus officinalis for Phytoremediation of Soil Contaminated with Petroleum Hydrocarbons (TPH and PAH), Zn, Pb and Cd Based on Toxicological Tests

by Teresa Steliga and Dorota Kluk

Toxics 2021, 9(7), 148; https://doi.org/10.3390/toxics9070148 - 25 Jun 2021

Cited by 16 | Viewed by 2764

Abstract

The article presents issues related to the possibility of using toxicological tests as a tool to monitor the progress of soil treatment contaminated with petroleum substances (TPH, PAH), Zn, Pb and Cd in bio-phytoremediation processes. In order to reduce the high content of [...] Read more.

The article presents issues related to the possibility of using toxicological tests as a tool to monitor the progress of soil treatment contaminated with petroleum substances (TPH, PAH), Zn, Pb and Cd in bio-phytoremediation processes. In order to reduce the high content of petroleum pollutants (TPH = 56,371 mg kg⁻¹ dry mass, PAH = 139.3 mg kg⁻¹ dry mass), the technology of stepwise soil treatment was applied, including basic bioremediation and inoculation with biopreparations based of indigenous non-pathogenic species of bacteria, fungi and yeasts. As a result of basic bioremediation in laboratory conditions (ex-situ method), the reduction of petroleum pollutants TPH by 33.9% and PAH by 9.5% was achieved. The introduction of inoculation with biopraparation-1 prepared on the basis of non-pathogenic species of indigenous bacteria made it possible to reduce the TPH content by 86.3%, PAH by 40.3%. The use of a biopreparation-1 enriched with indigenous non-pathogenic species of fungi and yeasts in the third series of inoculation increased to an increase in the degree of biodegradation of aliphatic hydrocarbons with long carbon chains and PAH by a further 28.9%. In the next stage of soil treatment after biodegradation processes, which was characterized by an increased content of heavy metals (Zn, Pb, Cd) and naphthalene, chrysene, benzo(a)anthracene and benzo(ghi)perylene belonging to polycyclic aromatic hydrocarbons, phytoremediation with the use of Melilotus officinalis was applied. After the six-month phytoremediation process, the following was achieved: Zn content by 25.1%, Pb by 27.9%, Cd by 23.2% and TPH by 42.2% and PAH by 49.9%. The rate of removal of individual groups of hydrocarbons was in the decreasing order: C₁₂–C₁₈ > C₆–C₁₂ > C₁₈–C₂₅ > C₂₅–C₃₆. PAHs tended to be removed in the following order: chrysene > naphthalene > benzo(a)anthracene > benzo(ghi)perylene. The TF and BCF coefficients were calculated to assess the capacity of M. officinalis to accumulate metal in tissues, uptake from soil and transfer from roots to shoots. The values of TF translocation coefficients were, respectively, for Zn (0.44), Pb (0.12), Cd (0.40). The calculated BCF concentration factors (BCF_roots > BCF_shoots) show that heavy metals taken up by M. officinalis are mainly accumulated in the root tissues in the following order Zn > Pb > Cd, revealing a poor metal translocation from the root to the shoots. This process was carried out in laboratory conditions for a period of 6 months. The process of phytoremediation of contaminated soil using M. officinalis assisted with fertilization was monitored by means of toxicological tests: Microtox, Ostracodtoxkit F^TM, MARA and Phytotoxkit^TM. The performed phytotoxicity tests have indicated variable sensitivity of the tested plants on contaminants occurring in the studied soils, following the sequence: Lepidium sativum < Sorghum saccharatum < Sinapis alba. The sensitivity of toxicological tests was comparable and increased in the order: MARA < Ostracodtoxkit F^TM < Microtox. The results of the toxicological monitoring as a function of the time of soil treatment, together with chemical analyses determining the content of toxicants in soil and biomass M. officinalis, clearly confirmed the effectiveness of the applied concept of bioremediation of soils contaminated with zinc, lead and cadmium in the presence of petroleum hydrocarbons. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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19 pages, 3987 KiB

Open AccessArticle

Synergistic Effects of Zinc Oxide Nanoparticles and Bacteria Reduce Heavy Metals Toxicity in Rice (Oryza sativa L.) Plant

by Nazneen Akhtar, Sehresh Khan, Shafiq Ur Rehman, Zia Ur Rehman, Amana Khatoon, Eui Shik Rha and Muhammad Jamil

Toxics 2021, 9(5), 113; https://doi.org/10.3390/toxics9050113 - 20 May 2021

Cited by 27 | Viewed by 3717

Abstract

Heavy metals (HMs) are toxic elements which contaminate the water bodies in developing countries because of their excessive discharge from industrial zones. Rice (Oryza sativa L) crops are submerged for a longer period of time in water, so irrigation with HMs polluted [...] Read more.

Heavy metals (HMs) are toxic elements which contaminate the water bodies in developing countries because of their excessive discharge from industrial zones. Rice (Oryza sativa L) crops are submerged for a longer period of time in water, so irrigation with HMs polluted water possesses toxic effects on plant growth. This study was initiated to observe the synergistic effect of bacteria (Bacillus cereus and Lysinibacillus macroides) and zinc oxide nanoparticles (ZnO NPs) (5, 10, 15, 20 and 25 mg/L) on the rice that were grown in HMs contaminated water. Current findings have revealed that bacteria, along with ZnO NPs at lower concentration, showed maximum removal of HMs from polluted water at pH 8 (90 min) as compared with higher concentrations. Seeds primed with bacteria grown in HM polluted water containing ZnO NPs (5 mg/L) showed reduced uptake of HMs in root, shoot and leaf, thus resulting in increased plant growth. Furthermore, their combined effects also reduced the bioaccumulation index and metallothionine (MTs) content and enhanced the tolerance index of plants. This study suggested that synergistic treatment of bacteria with lower concentrations of ZnO NPs helped plants to reduce heavy metal toxicity, especially Pb and Cu, and enhanced plant growth. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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17 pages, 1148 KiB

Open AccessFeature PaperArticle

Co-Cropping Indian Mustard and Silage Maize for Phytoremediation of a Cadmium-Contaminated Acid Paddy Soil Amended with Peat

by Sifan Wang, Yong Liu, Khalil Kariman, Jialin Li, Huihua Zhang, Fangbai Li, Yinglong Chen, Chongjian Ma, Chuanping Liu, Yuzhen Yuan, Zhiqiang Zhu and Zed Rengel

Toxics 2021, 9(5), 91; https://doi.org/10.3390/toxics9050091 - 21 Apr 2021

Cited by 8 | Viewed by 2641

Abstract

Co-cropping is an eco-friendly strategy to improve the phytoremediation capacity of plants growing in soils contaminated with heavy metals such as cadmium (Cd). This study was conducted to investigate the effects of co-cropping Indian mustard (Brassicajuncea) and silage maize ( [...] Read more.

Co-cropping is an eco-friendly strategy to improve the phytoremediation capacity of plants growing in soils contaminated with heavy metals such as cadmium (Cd). This study was conducted to investigate the effects of co-cropping Indian mustard (Brassicajuncea) and silage maize (Zeamays) and applying peat on the phytoremediation of a Cd-contaminated acid paddy soil via characterizing plant growth and Cd uptake in pot experiments. There were six planting patterns (Control: no plants; MI-2 and MI-4: mono-cropping of Indian mustard at low and high densities, respectively; MS: mono-cropping of silage maize; CIS-2 and CIS-4: co-cropping of Indian mustard at low and high densities with silage maize, respectively) and two application rates of peat (NP: 0; WP: 30 g kg⁻¹). When Indian mustard and silage maize were co-cropped, the shoot biomass of Indian mustard plants per pot was significantly (p < 0.05) lower than that obtained in the mono-cropping systems, with a substantial reduction (55–72%) in the same plant density group. The shoot biomass of silage maize plants in the mono-cropping systems did not differ significantly from that in the co-cropping systems regardless of the density of Indian mustard. The growth-promoting effect of the peat application was more pronounced in Indian mustard than silage maize. Under the low density of Indian mustard, the co-cropping systems significantly (p < 0.05) decreased Cd uptake by silage maize. Additionally, soil amendment with peat significantly (p < 0.05) increased shoot Cd removal rate and Cd translocation factor value in the co-cropping systems. Taken together, the results demonstrated that silage maize should be co-cropped with Indian mustard at an appropriate density in Cd-polluted soils to achieve simultaneous remediation of Cd-contaminated soils (via Indian mustard) and production of crops (here, silage maize). Peat application was shown to promote the removal of Cd from soil and translocation of Cd into shoots and could contribute to enhanced phytoremediation of Cd-contaminated acid paddy soil. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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11 pages, 6613 KiB

Open AccessEditor’s ChoiceArticle

Biosynthesized Iron Oxide Nanoparticles (Fe₃O₄ NPs) Mitigate Arsenic Toxicity in Rice Seedlings

by Sehresh Khan, Nazneen Akhtar, Shafiq Ur Rehman, Shaukat Shujah, Eui Shik Rha and Muhammad Jamil

Toxics 2021, 9(1), 2; https://doi.org/10.3390/toxics9010002 - 31 Dec 2020

Cited by 46 | Viewed by 5299

Abstract

Arsenic (As) contamination has emerged as a serious public health concern worldwide because of its accumulation and mobility through the food chain. Therefore, the current study was planned to check the effect of Bacillus subtilis-synthesized iron oxide nano particles (Fe₃O [...] Read more.

Arsenic (As) contamination has emerged as a serious public health concern worldwide because of its accumulation and mobility through the food chain. Therefore, the current study was planned to check the effect of Bacillus subtilis-synthesized iron oxide nano particles (Fe₃O₄ NP) on rice (Oryza Sativa L.) growth against arsenic stress (0, 5, 10 and 15 ppm). Iron oxide nanoparticles were extracellular synthesized from Bacillus subtilis with a desired shape and size. The formations of nanoparticles were differentiated through UV-Visible Spectroscopy, FTIR, XRD and SEM. The UV-Visible spectroscopy of Bacillus subtilis-synthesized nanoparticles showed that the iron oxide surface plasmon band occurs at 268 nm. FTIR results revealed that different functional groups (aldehyde, alkene, alcohol and phenol) were present on the surface of nanoparticles. The SEM image showed that particles were spherical in shape with an average size of 67.28 nm. Arsenic toxicity was observed in seed germination and young seedling stage. The arsenic application significantly reduced seed germination (35%), root and shoots length (1.25 and 2.00 cm), shoot/root ratio (0.289), fresh root and shoots weight (0.205 and 0.260 g), dry root and shoots weight (6.55 and 6.75 g), dry matter percentage of shoot (12.67) and root (14.91) as compared to control. Bacillus subtilis-synthesized Fe₃O₄ NPs treatments (5 ppm) remarkably increased the germination (65%), root and shoot length (2 and 3.45 cm), shoot/root ratio (1.24) fresh root and shoot weight (0.335 and 0.275 mg), dry root and shoot weight (11.75 and 10.6 mg) and dry matter percentage of shoot (10.40) and root (18.37). Results revealed that the application of Fe₃O₄ NPs alleviated the arsenic stress and enhanced the plant growth. This study suggests that Bacillus subtilus-synthesized iron oxide nanoparticles can be used as nano-adsorbents in reducing arsenic toxicity in rice plants. Full article

(This article belongs to the Special Issue Heavy Metal Toxicity Effects on Plants)

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