Plant growth stage influences heavy metal accumulation in leafy vegetables of garden cress and sweet basil

Abstract Background Contamination of vegetable crops with heavy metals is a great threat to human health. On the other hand, monitoring plant tissue content of heavy metals at different growth stages could have important implications. In this study, shoot and root samples of garden cress and sweet basil were collected from five farms, from heavy metal polluted fields located in Shahre Rey, south of Tehran, Iran, in either young (3 weeks old) or mature (7 weeks old) plants. The concentrations of cadmium (Cd), lead (Pb), nickel (Ni), arsenic (As), chromium (Cr), cobalt (Co), copper (Cu), manganese (Mn) and zinc (Zn) in plant tissues were determined using atomic absorption spectroscopy. In another study, 2 weeks (young) or 6 weeks old (mature) plants of garden cress were subjected to three concentrations of Cd and Pb (0, 5, 10 mg L−1) under hydroponic sand culture for 5 days, in which Hoagland formula was used for nutrient solution preparation. Results The results showed that root concentration of various heavy metals, particularly Cd, As, Ni, Co, Cu, Mn and Zn but not Pb were significantly higher than their shoot concentration in either crop under field sampling. The leaf concentration of some heavy metals was significantly different in seedling and older (mature) plant samples of either crop. Young plant leaves of sweet basil had significantly less Cd, Pb, As and higher Cu than mature plants, whereas young garden cress plants had similar Cd, Pb and higher As and Zn concentrations than mature plants. The Cr, Co, Mn and Zn concentrations were similar in young and mature plants of sweet basil. The Mn, Co, Cr and Ni concentration of young and mature plants of either crop was also similar. The result of hydroponic study showed that young plants of garden cress had higher potential to accumulate lead in shoot and root, particularly in lower (5 mg L−1) than higher (10 mg L−1) lead concentration; however, root Pb concentration at 10 mg L−1 Pb of nutrient solution showed no difference between young and mature plants. Regarding cadmium, young garden cress plants accumulated higher Cd than mature plants in their shoot, particularly under higher Cd levels (10 rather than 5 mg L−1) of nutrient solution; however, a wide difference in root Cd concentration was observed under low (5 mg L−1) than higher (10 mg L−1) cadmium concentration of nutrient solution. Conclusion The results of these two studies indicate that despite that young plants have a higher potential for heavy metal uptake and accumulation, the low difference in young and mature plants in the polluted fields may be due to the longer period of plant growth of mature plants that may increase the risk of exposure to polluted air and dust deposition containing high levels of heavy metals.

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Humic + Fulvic acid mitigated Cd adverse effects on plant growth, physiology and biochemical properties of garden cress

Scientific Reports ◽

10.1038/s41598-021-86991-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ertan Yildirim ◽

Melek Ekinci ◽

Metin Turan ◽

Güleray Ağar ◽

Atilla Dursun ◽

...

Keyword(s):

Heavy Metal ◽

Adverse Effects ◽

Plant Growth ◽

Fulvic Acid ◽

Pollution Level ◽

Hydroxyl Groups ◽

Cd Stress ◽

Garden Cress ◽

Cd Uptake ◽

Fresh Leaf

AbstractCadmium (Cd) is a toxic and very mobile heavy metal that can be adsorbed and uptaken by plants in large quantities without any visible sign. Therefore, stabilization of Cd before uptake is crucial to the conservation of biodiversity and food safety. Owing to the high number of carboxyl and phenolic hydroxyl groups in their structure, humic substances form strong bonds with heavy metals which makes them perfect stabilizing agents. The aim of this study was to determine the effects of humic and fulvic acid (HA + FA) levels (0, 3500, 5250, and 7000 mg/L) on alleviation of Cadmium (Cd) toxicity in garden cress (Lepidium sativum) contaminated with Cd (CdSO4.8H2O) (0, 100, and 200 Cd mg/kg) under greenhouse conditions. Our results showed that, Cd stress had a negative effect on the growth of garden cress, decreased leaf fresh, leaf dry, root fresh and root dry weights, leaf relative water content (LRWC), and mineral content except for Cd, and increased the membrane permeability (MP) and enzyme (CAT, SOD and POD) activity. However, the HA + FA applications decreased the adverse effects of the Cd pollution. At 200 mg/kg Cd pollution, HA + FA application at a concentration of 7000 mg/L increased the leaf fresh, leaf dry, root fresh, root dry weights, stem diameter, leaf area, chlorophyll reading value (CRV), MP, and LRWC values by 262%, 137%, 550%,133%, 92%, 104%, 34%, 537%, and 32% respectively, compared to the control. Although the highest H2O2, MDA, proline and sucrose values were obtained at 200 mg/L Cd pollution, HA + FA application at a concentration of 7000 mg/L successfully alleviated the deleterious effects of Cd stress by decreasing H2O2, MDA, proline, and sucrose values by 66%, 68%, 70%, and 56%, respectively at 200 mg/kg Cd pollution level. HA + FA application at a concentration of 7000 mg/L successfully mitigated the negative impacts of Cd pollution by enhanced N, P, K, Ca, Mg, Fe, Mn, Cu, Mn, Zn, and B by 75%, 23%, 84%, 87%, 40%, 85%, 143%, 1%, 65%, and 115%, respectively. In addition, HA + FA application at a concentration of 7000 mg/L successfully reduced Cd uptake by 95% and Cl uptake by 80%. Considering the plant growth parameters, the best results were determined when HA + FA concentration was 7000 mg/L. We have shown that, it is critical to apply a humic substance with high percentage of FA, which was 10% in this study, to mitigate the adverse effects of heavy metal stress on plant growth. In conclusion, the application of HA + FA may be suggested as an effective solution for reducing the Cd uptake of the plants by stabilizing Cd in soil and preventing translocation of Cd from the roots of plant to its shoot and leaves.

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Scope and future perspectives of phytoremediation

INTERNATIONAL JOURNAL PLANT SCIENCES ◽

10.15740/has/ijps/16.aaebssd/77-85 ◽

2021 ◽

Vol 16 (AAEBSSD) ◽

pp. 77-85

Author(s):

Sridevi Tallapragada ◽

Rajesh Lather ◽

Vandana ◽

Gurnam Singh

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Genetic Engineering ◽

Plant Growth ◽

Mycorrhizal Fungi ◽

Large Scale ◽

Negative Impact ◽

Heavy Metal Accumulation ◽

Plant Growth Promoting Bacteria ◽

Runoff Water

Phytoremediation is the plant-based technology that has emerged as a novel cost effective and ecofriendly technology in which green plants are used for extraction, sequestration and/or detoxification of the pollutants. Plants possess the natural ability to degrade heavy metals and this property of plants to detoxify contaminants can be used by genetic engineering approach. Currently, the quality of soil and water has degraded considerably due heavy metal accumulation through discharge of industrial, agricultural and domestic waste. Heavy metal pollution is a global concern and a major health threat worldwide. They are toxic, and can damage living organisms even at low concentrations and tend to accumulate in the food chain. The most common heavy metal contaminants are: As, Cd, Cr, Cu, Hg, Pb and Zn. High levels of metals in soil can be phytotoxic, leading to poor plant growth and soil cover due to metal toxicity and can lead to metal mobilization in runoff water and thus have a negative impact on the whole ecosystem. Phytoremediation is a green strategy that uses hyperaccumulator plants and their rhizospheric micro-organisms to stabilize, transfer or degrade pollutants in soil, water and environment. Mechanisms used to remediate contaminated soil includes phytoextraction, phytostabilization, phytotransformation, phytostimulation, phytovolatilization and rhizofiltration. Traditional phytoremediation method presents some limitations regarding their applications at large scale, so the application of genetic engineering approaches such as transgenic transformation, nanoparticles addition and phytoremediation assisted with phytohormones, plant growth-promoting bacteria and Arbuscular mycorrhizal fungi (AMF) inoculation has been applied to ameliorate the efficacy of plants for heavy metals decontamination. In this review, some recent innovative technologies for improving phytoremediation and heavy metals toxicity and their depollution procedures are highlighted.

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Elemental Profile of Heavy Metals in Garden cress, Coriander, Lettuce and Spinach, Commonly Cultivated in Kahrizak, South of Tehran- Iran

Open Agriculture ◽

10.1515/opag-2018-0004 ◽

2018 ◽

Vol 3 (1) ◽

pp. 32-37 ◽

Cited By ~ 12

Author(s):

Mohammad Kazem Souri ◽

Neda Alipanahi ◽

Mansoure Hatamian ◽

Mohammad Ahmadi ◽

Tsehaye Tesfamariam

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Leaf Tissue ◽

Heavy Metal Concentration ◽

Heavy Metal Accumulation ◽

Vegetable Crops ◽

Garden Cress ◽

Metal Concentrations ◽

Heavy Metal Concentrations

Abstract Heavy metal accumulation in vegetable tissues often poses a great risk for human health. In the present study, accumulation of heavy metal in green leafy vegetable crops of coriander, garden cress, lettuce and spinach were evaluated under waste water irrigation in fields located in Kahrizak, on the southern edge of the metropolitan city of Tehran, Iran. Atomic absorption spectrophotometery was used for determination of heavy metal concentrations in leaf tissue. The results showed that heavy metal concentrations in soil and irrigation water were significantly high than allowable levels. Analysis of plant leaf tissue showed that spinach and garden cress accumulated higher concentrations of heavy metals compared to coriander and lettuce plants. Central leaves of lettuce showed the lowest heavy metal concentration compared to outer leaves or leaves of other vegetable crops, and can be the safer product for fresh consumption. The results indicate that the vegetables produced in the region are not suitable for fresh consumption and the agricultural activities should change towards ornamental or industrial crops production.

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Heavy Metal Levels in Vegetables with Growth Stage and Plant Species Variations

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v36i4.11743 ◽

2012 ◽

Vol 36 (4) ◽

pp. 563-574 ◽

Cited By ~ 27

Author(s):

Habib Mohammad Naser ◽

Sarmin Sultana ◽

Nashir Uddin Mahmud ◽

Rebeca Gomes ◽

Shamsun Noor

Keyword(s):

Heavy Metal ◽

Plant Species ◽

Growth Stage ◽

Agricultural Research ◽

Leafy Vegetables ◽

World Health ◽

Growth Stages ◽

Metal Concentrations ◽

Rate Of Increase ◽

Metal Levels

Field experiment was conducted to compare and investigate the concentration levels of heavy metals in leafy vegetables with growth stage and plant species variations on an experimental field near the net house of Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh during November 2008 to January 2009. Seeds of spinach (Spinacia oleracea), red amaranth (Amaranthus tricolor) and amaranth (Amaranthus oleraseus) were sown on 14 November 2008. Plant and soil samples were collected at different growth stages, such as at 20, 30, 40, and 50 days after sowing (DAS). The concentrations of lead (Pb), cadmium (Cd), nickel (Ni), cobalt (Co), and chromium (Cr) in plant increased with the age of the plant, but the increase was not linear. The rate of increase of concentration of these metals at 20 to 30 DAS was found lower than that at 30 to 40 DAS, except Cr. Heavy metal content gradually increased at the early growing stage and fall during later stages of growth. The significant differences (P < 0.01) were observed between the mean metal concentrations in the three vegetables species. The Pb and Co concentrations in amaranth were found higher compared to those found in spinach and red amaranth. Spinach exhibited higher levels of Cd and Cr than those of other vegetables. However, the three vegetables did not differ significantly in its Ni concentration. The order of heavy metal level in different vegetables was Cd<Co<Pb<Ni<Cr. In vegetable species in respect of heavy metal concentration Cd, Ni, and Cr was highest in spinach and amaranth showed highest concentration in Pb and Co. The highest correlation between soil-plant was found for Cd, while the lowest for Ni. Metal concentrations in the vegetables studied were found lower than the maximum allowable level in India but the concentrations of Cd and Cr were higher than the allowable levels set by the World Health Organization (WHO). DOI: http://dx.doi.org/10.3329/bjar.v36i4.11743 Bangladesh J. Agril. Res. 36(4): 563-574, December 2011

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Remediation of Heavy Metals from Soil by Eco Approaches

Recent Advances in Biology and Medicine ◽

10.18639/rabm.2019.869984 ◽

2019 ◽

Vol 5 ◽

pp. 1

Author(s):

Manish Batham ◽

Jot Sharma ◽

◽

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Risk Factor ◽

Plant Growth ◽

Anthropogenic Activities ◽

Cost Effective ◽

Biodegradable Materials ◽

The Earth ◽

Heavy Metal Remediation ◽

High Level

The contamination of soil by anthropogenic activities is of great concern in recent times. There is an urgent demand of reliable and eco-friendly approaches for remediation of this concern. The current techniques for heavy metal remediation from contaminated soil are costly, time consuming, and harmful for the environment. Toxicity of heavy metals can reduce plant growth, and a high level of presence of these heavy metals is a risk factor to human and plant health. Heavy metals neither biodegradable materials nor are created. They occur naturally in the earth crust, and they reach the environment by human activities. Organic compounds can be degraded, but metals cannot degrade, and therefore effective cleanup requires its immobilization to reduce or remove toxicity. Recently, research focuses on cost-effective technologies to clean polluted areas. Vermiremediation and phytoremediation are two such useful techniques. In these eco-friendly techniques of remediation, the target plants accumulate, volatilize the contaminants, or convert them into some nontoxic forms, thus remediating the soil.

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Bioaccumulation of heavy metals and As in maize (Zea mays L) grown close to mine tailings strongly impacts plant development

10.21203/rs.3.rs-827219/v1 ◽

2021 ◽

Author(s):

ESTHER AURORA RUIZ HUERTA ◽

Maria Aurora Armienta Hernández ◽

Joseph G. Dubrovsky ◽

Juan Miguel Gómez Bernal

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Zea Mays ◽

Plant Growth ◽

Plant Development ◽

Mine Tailings ◽

Strong Impact ◽

Potentially Toxic Metals ◽

Microscopic Studies ◽

Mining Residues

Abstract Potentially toxic metals and metalloids present in mining residues can affect ecosystems, particularly plant growth and development. In this study we evaluated As and heavy metal (Fe, Zn, Cu, Cd, Pb) contents in maize (Zea mays L) plants grown in soils collected near (40 m), at intermediate (400 m) and remote (3000 m) distances from mine tailings near Taxco City, Mexico. Soils sampled near and at intermediate sites from the tailings contained high levels of heavy metals which were 3- to 55-fold higher compared to the control samples. The heavy metal and As content in plants reflected the soil contamination being the greatest for most studied elements in root samples followed by stems, leaves, and kernels. Though plants were capable of completing their life cycle and producing the seeds, high bioaccumulation levels had a strong impact on plant development. Abnormalities in the organs like malformations in reproductive structures (tassel and ear), reduction in the phytomer number and the plant height were present. Microscopic studies and morphometric analyses suggest that strongly affected plant growth result from negative and synergistic action of heavy metals and As in soils on cell growth and cell production. This study showed that maize grown near mine tailings accumulates high levels of heavy metals and As which decrease significantly plant yield and could be dangerous if consumed by animals and humans.

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Effects of Various Aeroponic Atomizers (Droplet Sizes) on Growth, Polyphenol Content, and Antioxidant Activity of Leaf Lettuce (Lactuca sativa L.)

Transactions of the ASABE ◽

10.13031/trans.13168 ◽

2019 ◽

Vol 62 (6) ◽

pp. 1475-1487

Author(s):

Imran Ali Lakhiar ◽

Jianmin Gao ◽

Xiuquan Xu ◽

Tabinda Naz Syed ◽

Farman Ali Chandio ◽

...

Keyword(s):

Antioxidant Activity ◽

Plant Growth ◽

Droplet Size ◽

Nutrient Solution ◽

Leafy Vegetables ◽

Polyphenol Content ◽

Total Polyphenol ◽

Positive Effects ◽

Total Polyphenol Content ◽

Droplet Sizes

HighlightsThe atomizer droplet size should be considered an important factor when designing aeroponic systems.Airless atomizers had significant positive effects on plant growth, total polyphenol content, and antioxidant activity.Airless atomizers and a spraying interval of 20 min on and 3 h off was the best combination for lettuce plants.Abstract. Throughout our literature review, the effects of various aeroponic atomizers (droplet sizes) on specific leafy plant growth and quality were minimally reported. Lettuce ( L.) is one of the most popular leafy vegetables consumed around the world. The present study sought to determine the effects of various aeroponic atomizers (droplet sizes) on the growth, total polyphenol content, and antioxidant activity of lettuce plants. Aeroponic systems were designed and manufactured using three kinds of atomizers: air-based (A1), airless (A2), and ultrasonic fogger (A3). The South China Agricultural leafy vegetable B nutrient solution was selected as the cultivating solution. Additionally, the spraying time and spraying interval were set at 20 min on and 3 h off. The sizes of the droplets generated by these atomizers were measured using a laser particle size analyzer, and the measured average droplet sizes generated by the A1, A2, and A3 atomizers were 23.281, 46.386, and 3.451 µm, respectively. The results showed that the lettuce plants treated with the A2 atomizers exhibited more significant effects on the growth, total polyphenol content, and antioxidant activity of the lettuce compared to those treated with the A1 and A3 atomizers. The results indicated that nutrient solution droplet size should be considered an essential factor when designing an aeroponic system. Keywords: Aeroponic, Antioxidant activity, Soilless, Spraying time, Total polyphenol content.

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Chromium, Cadmium, Lead, and Arsenic Concentrations in Water, Vegetables, and Seafood Consumed in a Coastal Area in Northern Vietnam

Environmental Health Insights ◽

10.1177/1178630220921410 ◽

2020 ◽

Vol 14 ◽

pp. 117863022092141

Author(s):

Nguyen Thi Minh Ngoc ◽

Nguyen Van Chuyen ◽

Nguyen Thi Thu Thao ◽

Nguyen Quang Duc ◽

Nguyen Thi Thu Trang ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Coastal Area ◽

Metal Contamination ◽

Heavy Metal Contamination ◽

Local Population ◽

Absorption Spectrometry ◽

Leafy Vegetables ◽

World Health ◽

Sample Collection

Background: Heavy metal contamination and related risks for the environment and human health are matters of increasing concern. Methods: The levels of 4 heavy metals (Cr, Cd, Pb, and As) were evaluated in 2 water types (surface and well), 4 types of seafood (tiger shrimp, stuffed snail, snake-head fish, and catfish), and 27 types of vegetables (12 leafy vegetables, 4 pea plants, 4 tuber vegetables, and 7 herbs) that are commonly consumed in northern coastal communes located in Vietnam. Atomic absorption spectrometry was employed for quantification. Results: The mean concentrations of heavy metals detected in water, seafood, and vegetable samples exceeded the national permitted standards and World Health Organization (WHO) recommendation values by at least 2-fold, 2.5-fold, and 5-fold for surface water, vegetables, and well water, respectively. The concentrations of all 4 heavy metals detected in seafood samples were higher than the standards. The levels of heavy metals decreased with increasing distance between the sample collection point and the pollution source. Conclusions: This is the first report of heavy metal contamination of common sources of food and water in the northern coastal area of Vietnam. Significantly, the concentrations of heavy metals detected in study samples exceeded the regulatory limits. These results underscore the importance of continued monitoring and the development of intervention measures to ensure that the quality of food and water meets established standards and protects the health of the local population.

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Plant growth, development and change in GSH level in safflower (Carthamus tinctorius L.) exposed to copper and lead

Archives of Biological Sciences ◽

10.2298/abs140910006l ◽

2015 ◽

Vol 67 (2) ◽

pp. 385-396 ◽

Cited By ~ 14

Author(s):

Shufen Li ◽

Guojun Zhang ◽

Wujun Gao ◽

Xingpeng Zhao ◽

Chuanliang Deng ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Plant Growth ◽

Root Length ◽

Growth And Development ◽

Prolonged Exposure ◽

Carthamus Tinctorius ◽

Short Exposure ◽

Pcr Analysis ◽

Root Numbers

The effects of exposure to heavy metals, copper (Cu) and lead (Pb) in the soil, separately and in combination, were examined in Safflower (Carthamus tinctorius L.). Plant growth and development, GSH level and GSH2 expression at seedling, branching, and flowering stages were studied. Cu at lower concentrations had a stimulating effect on seedling height and root length. A significant positive correlation was observed between heavy metal concentrations and inhibition of plant growth. Plant height, root length and lateral root numbers decreased progressively with increasing concentrations of Cu and Pb. Except at the seedling stage, the metal mixture elicited a synergistic effect on safflower growth and development. The GSH content was significantly reduced in both safflower roots and leaves at increased concentrations of heavy metals, with the exception of the treatment with a low concentration of Cu that resulted in a slightl increase in GSH content at the seedling and branching stages. RT-PCR analysis revealed a negative correlation between GSH2 expression levels and metal concentration. Short exposure to low concentrations of Cu induce an increase in GSH synthesis to preserve normal plant growth, whereas prolonged exposure and large Cu and Pb concentrations affect the GSH metabolic chain, and are severely toxicity. The findings obtained in this study enhance our understanding of the role of the GSH pool in the response of plants to heavy metal-induced stress, and serve as a basis for improved cultivation of safflower.

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Genome-wide analysis of metallothionein gene family in maize to reveal its role in development and stress resistance to heavy metal

Biological Research ◽

10.1186/s40659-021-00368-w ◽

2022 ◽

Vol 55 (1) ◽

Author(s):

Canhong Gao ◽

Kun Gao ◽

Huixian Yang ◽

Tangdan Ju ◽

Jingyi Zhu ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Plant Growth ◽

Stress Resistance ◽

Binding Sites ◽

Growth And Development ◽

Expression Profiles ◽

Expression Patterns ◽

Plant Growth And Development ◽

Specific Expression

Abstract Background Maize (Zea mays L.) is a widely cultivated cereal and has been used as an optimum heavy metal phytoremediation crop. Metallothionein (MT) proteins are small, cysteine-rich, proteins that play important roles in plant growth and development, and the regulation of stress response to heavy metals. However, the MT genes for maize have not been fully analyzed so far. Methods The putative ZmMT genes were identified by HMMER.The heat map of ZmMT genes spatial expression analysis was generated by using R with the log2 (FPKM + 1).The expression profiles of ZmMT genes under three kinds of heavy metal stresses were quantified by using qRT-PCR. The metallothionein proteins was aligned using MAFFT and phylogenetic analysis were constructed by ClustalX 2.1. The protein theoretical molecular weight and pI, subcellular localization, TFs binding sites, were predicted using ProtParam, PSORT, PlantTFDB, respectively. Results A total of 9 ZmMT genes were identified in the whole genome of maize. The results showed that eight of the nine ZmMT proteins contained one highly conserved metallothio_2 domain, while ZmMT4 contained a Metallothio_PEC domain. All the ZmMT proteins could be classified into three major groups and located on five chromosomes. The ZmMT promoters contain a large number of hormone regulatory elements and hormone-related transcription factor binding sites. The ZmMT genes exhibited spatiotemporal specific expression patterns in 23 tissues of maize development stages and showed the different expression patterns in response to Cu, Cd, and Pb heavy metal stresses. Conclusions We identified the 9 ZmMT genes, and explored their conserved motif, tissue expression patterns, evolutionary relationship. The expression profiles of ZmMT genes under three kinds of heavy metal stresses (Cu, Cd, Pb) were analyzed. In summary, the expression of ZmMTs have poteintial to be regulated by hormones. The specific expression of ZmMTs in different tissues of maize and the response to different heavy metal stresses are revealed that the role of MT in plant growth and development, and stress resistance to heavy metals.

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