Iron (Fe) deficiency and excess cadmium (Cd) in rice grain are important problems to be solved in agricultural production. Previous studies have shown that OsVIT1 and OsVIT2 are vacuolar iron transporters. In this study, wild-type ZH11 was selected as the background material and OsVIT1 and OsVIT2 were overexpressed in endosperm by using endosperm specific promoter Glb-1. Field experiments were conducted to study the effect of OsVIT1 and OsVIT2 overexpression on Fe and Cd accumulation in different parts of rice. The results showed that OsVIT1 overexpression in endosperm significantly reduced Fe content in grain by about 50%, while significantly increased zinc (Zn) and copper (Cu) contents in straw and Cu content in grain. OsVIT2 overexpression in endosperm significantly decreased Fe and Cd contents in grain by about 50%, and significantly increased Fe content in straw by 45%-120%. Overexpression of OsVIT1 and OsVIT2 in endosperm did not affect the agronomic traits of rice. In conclusion, OsVIT1 and OsVIT2 overexpression in endosperm reduced Fe accumulation in rice grain, which did not achieve the expected effect. OsVIT2 overexpression in endosperm also decreased Cd accumulation in grain and increased Fe accumulation in straw, which provided reference for iron biofortification and cadmium reduction in rice.
Cadmium ; Endosperm/chemistry* ; Oryza/genetics* ; Iron ; Zinc ; Edible Grain ; Soil Pollutants

Excessive levels of cadmium (Cd) in soil exert serious negative impacts on soil ecosystems. Microorganisms are a common component of soil and show great potential for mitigating soil Cd. This review summarizes the application and remediation mechanisms of microorganisms, microbial-plants, and microbial-biochar in Cd-contaminated soil. Microorganisms such as Bacillus, Acinetobacter, Pseudomonas, and arbuscular mycorrhizal fungi (AMF) can change the biological validity of Cd through adsorption, mineralization, precipitation and dissolution. Different factors such as pH, temperature, biomass, concentration, and duration have significant effects on Cd bioavailability by microorganisms. Pseudomonas, Burkholderia, and Flavobacterium can promote the uptake of Cd²⁺ by hyperaccumulator through promotion and activation. Biochar, a soil amendment, possesses unique physicochemical properties and could act as a shelter for microorganisms in agriculture. The use of combined microbial-biochar can further stabilize Cd compared to using biochar alone.
Cadmium ; Ecosystem ; Soil Pollutants ; Charcoal/chemistry* ; Soil/chemistry*

In this study, the effects of two plant growth-promoting bacteria Klebsiella michiganensis TS8 and Lelliottia Jeotgali MR2 on the growth and cadmium (Cd) uptake of Arabidopsis thaliana under Cd stress were explored. A wild-type Arabidopsis thaliana was selected as the experimental plant and was planted at different Cd concentrations. MR2 and TS8 bacterial suspensions were sprayed onto the rhizospheric soil during the planting process. The initial Cd concentration of the bought soil was 14.17 mg/kg, which was used as the pot soil of the low-concentration Cd treatment group (LC). The concentration of soil Cd at high-concentration Cd treatment group (HC) were 200 mg/kg higher than that at LC group. Compared with the control group, MR2 suspension significantly promoted the growth of A. thaliana at both low and high concentrations, while TS8 strain and MR2_TS8 mixture only exhibited growth-promoting effect at high concentration. However, it was noteworthy that, TS8 suspension significantly reduced the Cd content in the underground parts of A. thaliana (60% and 59%), and significantly improved the Cd content in the aboveground parts of A. thaliana (234% and 35%) at both low and high concentrations. In addition, at low concentration, both single strain and mixed strains significantly improved the transformation from reducible Cd to acid-extractable Cd in soil, promoted Cd intake, and thereby reduced the total Cd content in soil. Therefore, the rational application of plant growth-promoting bacteria may improve crop yield and remediate Cd contamination in soil.
Arabidopsis ; Bacteria ; Biodegradation, Environmental ; Cadmium/pharmacology* ; Enterobacteriaceae ; Klebsiella ; Plant Roots/chemistry* ; Soil ; Soil Pollutants

To screen the available tomato pollution-safe cultivar varieties and reduce the potential food safety risks in Cd-polluted areas, the differences of Cd accumulation in different tomato (Solanum lycopersicum) varieties in southern China were studied by soil culture and hydroponic experiments. Firstly, the high and low accumulation varieties were selected from 25 tomato varieties under 2.94 mg/kg Cd stress by soil culture test, and then the responses of high and low accumulation tomato varieties to Cd stress were determined by hydroponic experiments. The results of soil culture test show that under 2.94 mg/kg Cd stress, there were significant differences in plant height, total biomass and yield among 25 tomato cultivars, and the Cd contents of fruits of all 25 tomato cultivars exceeded the highest limit value (0.05 mg/kg) of CAC (Codex alimentarius commission). Through cluster analysis, 7, 4 and 14 varieties accumulating relatively high, medium, and low concentrations of Cd in the fruits were screened, among which the highest, the lowest, and the average Cd contents in the fruits were 3.06 mg/kg DW, 1.47 mg/kg DW, and 2.21 mg/kg DW, respectively. The results of hydroponic experiment show that under the same concentration of Cd stress, Qiantangxuri F1, a high Cd accumulating variety, absorbed Cd faster, accumulated more Cd, used shorter oxidative stress response time and had stronger tolerance to Cd than Zhefen 3053, a low Cd accumulating variety. The typical high and low Cd accumulating varieties can provide a reference for agricultural production in heavy metal polluted areas and the development of molecular-assisted breeding methods of PSC. At present, cultivating low Cd accumulating PSC varieties and dynamic monitoring of Cd contents in tomato fruits are feasible methods in medium and light Cd-polluted areas.
Antioxidants ; Cadmium/toxicity* ; China ; Lycopersicon esculentum ; Plant Breeding ; Plant Roots/chemistry* ; Soil Pollutants/toxicity*

The remediation of heavy-metal (HM) contaminated soil using hyperaccumulators is one of the important solutions to address the inorganic contamination widely occurred worldwide. Hyperaccumulators are able to hyperaccumulate HMs, but their planting, growth, and extraction capacities are greatly affected by HM stress. The application of arbuscular mycorrhizal fungi (AMF) enhances the function of hyperaccumulators by combining the functional advantages of both, improving the efficiency of remediation, shortening the remediation cycle, and maintaining the stability and persistence of the remediation. Thus, the combined use of AMF with hyperaccumulators has broad prospects for application in the management of increasingly complex and severe HM pollution. This review starts by defining the concept of hyperaccumulators, followed by describing the typical hyperaccumulators that were firstly reported in China as well as those known to form symbioses with AMF. This review provides a systematic and in-depth discussion of the effects of AMF on the growth of hyperaccumulators, as well as the absorption and accumulation of HMs, the effects and mechanism on the hyperaccumulator plus AMF symbiosis to absorb and accumulate HMs. AMF enhances the function of hyperaccumulators on the absorption and accumulation of HMs by regulating the physicochemical and biological conditions in the plant rhizosphere, the situation of elements homeostasis, the physiological metabolism and gene expression. Moreover, the symbiotic systems established by hyperaccumulators plus AMF have the potential to combine their abilities to remediate HMs-contaminated habitat. Finally, challenges for the combined use of remediation technologies for hyperaccumulator plus AMF symbiosis and future directions were prospected.
Biodegradation, Environmental ; Metals, Heavy ; Mycorrhizae/chemistry* ; Plant Roots/chemistry* ; Soil Pollutants ; Symbiosis

The hydroponic culture test method was used to study the physiological and biochemical responses of Paulownia fortunei seedlings under Zn stress, Cd stress, and combined Zn and Cd stress as well as changes in the enrichment and transfer characteristics of heavy metals. Under single and combined heavy metal stress, the biomass, plant height, and peroxidase (POD) activity of P. fortunei decreased as the treatment concentration increased. Combined Zn and Cd affected adversely plant height and biomass. As the concentration of Zn increased when applied alone, the chlorophyll content and catalase (CAT) activity of P. fortunei first increased and then decreased, the superoxide dismutase (SOD) activity increased, and the aboveground malondialdehyde (MDA) content first decreased and then increased. As the concentration of Cd increased when applied alone, chlorophyll content and CAT activity increased, and SOD activity and aboveground MDA content first increased and then decreased. Under both Cd and Zn, the physiological response was more complex. Cd in the seedlings of P. fortunei was concentrated in the root. In contrast, Zn was concentrated in the upper part of the ground, and its transfer coefficient was greater than 1.00. Thus, the addition of Zn promotes the transfer of heavy metals to the above-ground portions of plants. Generally, P. fortunei can effectively promote ecological restoration under complex forms of heavy metal pollution.
Cadmium ; Chlorophyll ; Metals, Heavy ; Plant Roots/chemistry* ; Seedlings ; Soil Pollutants ; Stress, Physiological ; Superoxide Dismutase ; Zinc

In order to understand the pollution of heavy metals in Guizhou soil planting Eucommia ulmoides,the paper has determined the contents of five heavy metals respectively( Cu,Cd,Pb,Hg and As) by atomic absorption spectrophotometry. The soil environmental quality by single factor pollution index was evaluated,nemerow integrated pollution index and potential ecological risk index,the correlation of 5 heavy metals was analyzed and the relationship between heavy medals content and p H value was discussed. The results showed that: ①The soils of LP,SB and ZA-2 had low heavy metals content,LP soil met the first national standard,and other soils met the second national standard; ②The soils of LP,ZA-1 and ZA-2 were all in a clean state,while HX and BZ-1 were in a light pollution state,and the pollution degree was Cu>Pb>As>Cd>Hg; ③The soil of BZ-2 was light warning( medium ecological risk),the soils of HX,BZ-1 and MT were early warning( low ecological risk),the main warning source was Cu and Pb,and the rest were no warning( no ecological risk); ④Cd and As were positively correlated with Pb and Hg,and Cd,Pb and As were positively correlated with p H. The research showed that the soils of LP,SB,ZA-1 and ZA-2 were clean and could be used for E. ulmoides to continue planting,the soils of HX,MT,BZ-1 and BZ-2 were polluted and should be treated in time by effective measures.
China ; Environmental Monitoring ; Eucommiaceae ; Metals, Heavy ; analysis ; Risk Assessment ; Soil ; chemistry ; Soil Pollutants ; analysis

In this study, we investigate the bioaccessibility of heavy metals (Cu, Pb, As, Cd and Hg) in wild Artemisia annua and use target hazard quotients (THQ) proposed by US Environmental Protection Agency to assess the health risk under the heavy metal exposure. The results showed that the bioaccessibility of Cu, Pb, As, Cd and Hg in A. annua are 0.77, 0.66, 0.46, 0.68 and 0, respectively, and that the value of THQ for adults and children were 0.030 and 0.025 calculated by risk assessment model. The results indicated that the heavy metals in A. annua were not able to be completely absorbed by human body and that their contents were in a safe range. In this study, by combining the bioavailability of heavy metal and health risk assessment, we assessed the security of heavy metals of wild A. annua, which will provide reference for the standard of heavy metals for medicinal materials.
Artemisia annua ; chemistry ; metabolism ; Consumer Product Safety ; Drug Contamination ; Humans ; Metals, Heavy ; analysis ; metabolism ; Risk Assessment ; Soil Pollutants ; analysis ; metabolism

Risk assessment considers the situations and characteristics of the exposure environment and host. Various physiological variables of the human body reflects the characteristics of the population that can directly influence risk exposure. Therefore, identification of exposure factors based on the Korean population is required for appropriate risk assessment. It is expected that a handbook about general exposure factors will be used by professionals in many fields as well as the risk assessors of the health department. The process of developing the exposure factors handbook for the Korean population will be introduced in this article, with a specific focus on the general exposure factors including life expectancy, body weight, surface area, inhalation rates, amount of water intake, and soil ingestion targeting the Korean population. The researchers used national databases including the Life Table and the 2005 Time Use Survey from the National Statistical Office. The anthropometric study of size in Korea used the resources provided by the Korean Agency for Technology and Standards. In addition, direct measurement and questionnaire surveys of representative samples were performed to calculate the inhalation rate, drinking water intake, and soil ingestion.
Asian Continental Ancestry Group ; Body Surface Area ; Body Weight/physiology ; Drinking Water/standards ; *Environmental Exposure ; Humans ; Inhalation/*physiology ; Life Expectancy ; Republic of Korea ; Risk Assessment ; Soil Pollutants/chemistry

A high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) method was developed for determining degradation dynamics and final residues of myclobutanil 25% WG in ginseng root, stem, leaf and soil. The samples were extracted with acetonitrile, cleaned-up with primary secondary amine (PSA) solid phase extraction cartridge, separated by Kromasil Eternity-5-C18 (2.1 mm x 150 mm, 5 microm) column with a gradient of acetonitrile and 0.1% formate in water as mobile phases, and analyzed with the multiple reaction monitoring (MRM) in positive ion mode by employing the external standard method. The average recoveries and the relative standard derivations (RSDs) of myclobutanil at the spiked level of 0.01-0.20 mg x kg(-1) were 80.9%-90.7% and 5.54%-9.29%, respectively, and the limit of quantification (LOQ) was 0.005 mg x kg(-1). The method with good reproducible, high precision and low detection limit could meet the requirements of residual analysis on ginseng production. The half-lives of myclobutanil were from 6.25 days to 9.94 days in ginseng root, stem, leaf and soil at spraying dosage of 1 152 g x hm(-2) The final residues were below 0.060 1 mg x kg(-1) in root, below 0.081 7 mg x kg(-1) in stem, 0.006 0-0.102 2 mg x kg(-1) in leaf and below 0.037 6 mg x kg(-1) in soil at spraying dosage range from 576 to 1 152 g x hm(-2). It is recommended that the MRLs of myclobutanil in dried ginseng may be suggested to be 0.10 mg x kg(-1) temporarily, and the preharvest interval was set at 35 days.
Chromatography, High Pressure Liquid ; methods ; Drug Contamination ; Fungicides, Industrial ; chemistry ; Nitriles ; chemistry ; Panax ; chemistry ; Plant Leaves ; chemistry ; Plant Roots ; chemistry ; Plant Stems ; chemistry ; Soil Pollutants ; chemistry ; Spectrometry, Mass, Electrospray Ionization ; methods ; Tandem Mass Spectrometry ; methods ; Triazoles ; chemistry