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Grafting is an effective horticultural method to reduce Cd accumulation in crops. However, the mechanism of grafting inducing the decrease in Cd content in scions remains unclear. This study evaluated the effect of grafting on fruit quality, yield, and Cd content of Solanum melongena, and explored the potential mechanism of grafting reducing Cd content in scions. In the low Cd-contaminated soil, compared with un-grafted (UG) and self-grafted plants (SG), the fruit yield of inter-grafted plants (EG) increased by 38 %, and the fruit quality was not markedly affected. In EG, the decrease in total S and Cd content was not related to organic acids and thiol compounds. The decrease in total S and Cd content in EG leaves and fruits was closely related to the synthesis and transportation of glucosinolates (GSL). The genes encoding GSL synthesis in leaves, such as basic helix-loop-helix, myelocytomatosis proteins, acetyl-CoA, cytochrome P450, and glutathione S-transferases, were significantly downregulated. In EG leaves, the contents of five of the eight amino acids involved in GSL synthesis decreased significantly (P < 0.05). Notably, total GSL in EG stems, leaves, and fruits had a significant linear correlation with total S and Cd. In summary, the decrease in total S and Cd content in scions caused by grafting is closely related to GSL. Our findings provide a theoretical basis for the safe use of Cd-contaminated soil, exploring the long-distance transport of Cd in plants and cultivating crops with low Cd accumulation., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Graphene oxide (GO)-promoted microbial degradation technology is considered an important strategy to eliminate polycyclic aromatic hydrocarbons (PAHs) in the environment; however, the mechanism by which GO affects microbial degradation of PAHs has not been fully studied. Thus, this study aimed to analyze the effect of GO-microbial interaction on PAHs degradation at the microbial community structure, community gene expression, and metabolic levels using multi-omics combined technology. We treated PAHs-contaminated soil samples with different concentrations of GO and analyzed the soil samples for microbial diversity after 14 and 28 days. After a short exposure, GO reduced the diversity of soil microbial community but increased potential degrading microbial abundance, promoting PAHs biodegradation. This promotion effect was further influenced by the GO concentration. In a short period of time, GO upregulated the expression of genes involved in microbial movement (flagellar assembly), bacterial chemotaxis, two-component system, and phosphotransferase system in the soil microbial community and increased the probability of microbial contact with PAHs. Biosynthesis of amino acids and carbon metabolism of microorganisms were accelerated, thereby increasing the degradation of PAHs. With the extension of time, the degradation of PAHs stagnated, which may be due to the weakened stimulation of GO on microorganisms. The results showed that screening specific degrading microorganisms, increasing the contact area between microorganisms and PAHs, and prolonging the stimulation of GO on microorganisms were important means to improve the biodegradation efficiency of PAHs in soil. This study elucidates how GO affects microbial PAHs degradation and provides important insights for the application of GO-assisted microbial degradation technology., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Cadmium (Cd) pollution in farmland soil increases the probability of wastage of land resources and compromised food safety. Grafting can change the absorption rates of elements in crops; however, there are few studies on grafting in bulk grain and cash crops. In this study, Glycine max was used as a scion and Luffa aegyptiaca as a rootstock for grafting experiments. The changes in total sulfur and Cd content in the leaves and grains of grafted species were determined for three consecutive generations, and the gene expression and DNA methylation status of the leaves were analyzed. The results show that grafting significantly reduced the total sulfur and Cd content in soybean leaves and grains; the Cd content in soybean leaves and grains decreased by >50 %. The plant's primary sulfur metabolism pathway was not significantly affected. Glucosinolates and DNA methylation may play important roles in reducing total sulfur and Cd accumulation. Notably, low sulfur and low Cd traits can be maintained over two generations. Our study establishes that grafting can reduce the total sulfur and Cd content in soybean, and these traits can be inherited. In summary, grafting technology can be used to prevent soybean from accumulating Cd in farmland soil. This provides a theoretical basis for grafting to cultivate crops with low Cd accumulation., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)

Rare Earth Elements (REEs) are increasingly being used in agriculture and are also used to produce high end technological devices, thereby increasing their anthropogenic presence in the environment. However, the ecotoxicological mechanism of REEs on organisms is not fully understood. In this study, the effects of gadolinium (Gd) addition on Arabidopsis thaliana (L.) were investigated at both physiological and molecular levels. Four treatments (0, 10, 50 and 200 μmol·L -1 Gd) were used in the exposure tests. Biomass, root length and chlorophyll content in shoots/roots were measured to investigate the plant's physiological response to Gd stress. Random amplified polymorphic (RAPD)-Polymerase Chain Reaction (PCR) and methylation sensitive arbitrarily primed (MSAP)-PCR were used to investigate changes in genetic variation and DNA methylation of A. thaliana when exposed to Gd. At the physiological level, it was found that low concentration of Gd (10 μmol·L -1 ) could significantly increase the plant biomass and root length, while the growth of A. thaliana was significantly inhibited when exposed to 200 μmol·L -1 of Gd, yet the total soluble protein content in aerial plant parts increased significantly by 24.2% when compared to the control group. Among the 12 primers considered in the RAPD assessment, at the molecular level, only four primers revealed different patterns in their genomic DNA. Compared to the control group, the treatment with 50 μmol·L -1 of Gd was associated with lower polymorphism, while the treatment with 200 μmol·L -1 of Gd was associated with higher polymorphism. The polymorphism frequencies for the 50 μmol·L -1 of Gd and the 200 μmol·L -1 of Gd were 4.67% and 20.33%, respectively. The MSAP analysis revealed that the demethylation (D) type of Arabidopsis genomic DNA increased significantly under 10 and 50 μmol·L -1 of Gd, while the methylation (M) type was also significantly increased under 200 μmol·L -1 of Gd. Generally, the total methylation polymorphism (D+M) increased with an increase of Gd concentration. It was found that high concentrations of Gd appeared to cause DNA damage, but low concentrations of Gd (as low as 10 μmol·L -1 ) were associated with DNA methylation change. Further, it was verified by Real time Reverse Transcription PCR (RT-PCR) on the bands detected by the MSAP analysis, that the genes relative to processes including cell cycle, oxidative stress and apoptosis, appeared to be regulated by methylation under Gd stress. These findings reveal new insight regarding ecotoxicity mechanisms of REEs on plants., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

A key question to be asked when developing regional water quality criteria with scarce toxicity data is whether such data need to be locally derived. To address this, ammonia toxicity data from local aquatic species in the Liao River were compared against data from species native and non-native to China, based on comparisons of the overall trends of species sensitivity distributions and derived water quality criteria. Liao River data were acquired by acute and chronic tests using five local freshwater invertebrate species, and then compiled alongside published data from Chinese national guidelines and international literature. Models of best fit using three species sensitivity distribution approaches (log-logistic, log-normal, and Burr III) did not vary markedly (r 2 >0.9), and no specific model provided a best fit across all data sets. The comparisons of the overall trend of species sensitivity distribution curves showed no significant differences at either a national (Chinese native taxa tested in China versus non-native taxa) or regional level (Liao River taxa versus non-Liao River taxa). The comparisons also revealed that the inclusion or exclusions of different ecological groups had little influence on the overall trends of species sensitivity distributions. These findings suggested data on non-local and non-native species, and data from local species tested elsewhere, could be appropriate for guiding the derivation of ammonia water quality criteria for regions such as Liao River. However, caution is needed when using hazardous concentration 5% values in the development of site-specific water quality criteria for a river basin due to the considerable variation observed for ammonia (16.8-56.6 mg/L), although these differences were not statistically significant. Based on the toxicity test evaluation, a preliminary acute value of 10.0 mg/L and chronic value of 1.7 mg/L (at pH of 7.0 and 20 °C) are proposed as site-specific ammonia water quality criteria for the Liao River, China., (Copyright © 2018. Published by Elsevier Inc.)

Heavy metal cadmium (Cd) pollution in farmland has become a serious threat to food security globally. In this work, a grafting technique was applied to eggplant (Solanum melongena) and tomato (Solanum lycopersicum) plants using Solanum torvum as rootstock to investigate effects of grafting on Cd accumulation in shoots. The un-grafted, self-grafted, and grafted plants were grown in soils containing 2 mg kg -1 Cd. Results showed that grafting on S. torvum could efficiently reduce Cd accumulation in leaves of eggplant and tomato, and the decrease was 89% and 72%, respectively. With S. torvum as rootstock, Cd concentrations were 1.11 mg kg -1 and 6.58 mg kg -1 in leaves of grafted eggplant and tomato, which were significantly decreased as compared with un-grafted plants (10.12 mg kg -1 and 23.19 mg kg -1 , respectively, p < 0.05). In addition, Cd concentrations were 12.11 mg kg -1 and 29.47 mg kg -1 in leaves of self-grafted eggplant and tomato, respectively, which was similar to those in un-grafted eggplant, but more than those in un-grafted tomato (p < 0.05). This suggests that the S. torvum rootstock, and not the grafting operation, was responsible for efficient reduction of Cd accumulation in shoots of eggplant and tomato plants. Furthermore, total sulfur and sulfate (SO 4 2- ) concentrations analysis revealed that there was a similar trend between Cd accumulation and total sulfur or SO 4 2- concentrations in leaves of plants tested. Additionally, a strong positive correlation between Cd accumulation and total sulfur or SO 4 2- concentrations occurred in leaves of eggplant and tomato plants. Thus, sulfur, mainly SO 4 2- , in leaves may play an important regulatory role in Cd accumulation of eggplant and tomato plants. This study provides the theoretical and technical support for applying grafting technique for the safe practice of farming in Cd-contaminated agricultural soil., (Copyright © 2018. Published by Elsevier B.V.)

Water quality criteria (WQC) are considered to be an effective management tool for protecting aquatic environments. To derive site-specific WQC for an area, local data based on local species are essential to improve the applicability of WQC derived. Due to the paucity of local fish data available for the development of site-specific WQC for the Liao River, China, four local and widespread fishes (Pseudorasbora parva， Abbottina liaoningensis, Ctenogobius giurinus, and Misgurnus anguillicaudatus) were chosen to test their sensitivities to ammonia, cadmium and nitrobenzene. These compounds are common and regularly-measured pollutants in Chinese rivers. In addition to the published data for species resident in the Liao River, site-specific WQC for the three chemicals were derived using both a log-logistic species sensitivity distribution (SSD) and the method recommended by the USEPA, in line with current best practice, which were then compared with Chinese national WQC. It was found that A. liaoningensis was the most sensitive, followed, in order, by P. parva, C. giurinus and M. anguillicaudatus was the least sensitive, and this trend was the same to all three chemicals tested. When comparing the SSD derived solely from previously-published data with that including our data on local fish, there were significant differences identified among parameters describing the SSD curves for ammonia and nitrobenzene and significant differences were detected for site-specific WQC derived for all of the three chemicals. Based on the dataset with local fish data taxa, site-specific WQC of Liao River for ammonia, cadmium, and nitrobenzene were derived to be 20.53mg/L (at a pH of 7.0 and temperature of 20°C), 3.76μg/L (at a hardness of 100mg/L CaCO 3 ), and 0.49mg/L, respectively. Using the same deriving method for each chemical, the national Chinese WQC were higher than site-specific WQC derived in this study for ammonia (national WQC of 25.16mg/L) and nitrobenzene (national WQC of 0.57mg/L), while the national WQC for cadmium was lower (national WQC of 1.81μg/L). These results indicated that published data can be helpful for use when deriving site-specific WQC but that there were differences between site-specific and national WQC which may lead to either over- or under-protection depending on the pollutant if national WQC were used as the basis for the water management of specific river systems, like the Liao River., (Copyright © 2017. Published by Elsevier Inc.)

Accumulating evidence demonstrates that the aberrant expression of cell cycle regulation and DNA repair genes can result in abnormal cell proliferation and genomic instability in eukaryotic cells under different stresses. Herein, Arabidopsis thaliana (Arabidopsis) seedlings were grown hydroponically on 0.5 × MS media containing cadmium (Cd) at 0-2.5mgL -1 for 5d of treatment. Real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis revealed that expression of DNA damage repair and cell cycle regulation genes, including BRCA1, MRE11, WEE1, CDKA;1 and PCNA1, showed an inverted U-shaped dose-response. In contrast, notably reduced expression was observed for G1-to-S transition-related genes, Histone H4, E2Fa and PCNA2; DSB end processing, GR1; G2-to-M transition-related gene, CYCB1;1; and DNA mismatch repair, MSH2, MSH6 and MLH1 genes in root tips exposed to 0.125-2.5mg/L Cd for 5d. Flow cytometry (FCM) analysis revealed significant increases of cells with a 2 C nuclear content and with a 4 C and 8 C nuclear content under Cd stresses of 0.125 and 1-2.5mgL -1 , respectively. Our results suggest that 0.125mgL -1 Cd-induced DNA damage induced the marked G1/S arrest, leading to accelerated growth in root tips, while 1.0-2.5mgL -1 Cd-induced DNA damage caused a notable G2/M arrest in root tips, leading to reduced growth in root tips. This may be a protective mechanism that prevents cells with damaged DNA from dividing under Cd stress., (Copyright © 2017 Elsevier Inc. All rights reserved.)

This work was initiated to study the competitive sorption effect on phenanthrene and pyrene extraction during the aging process in phaeozem, burozem, aquorizem and krasnozem with or without freeze-thawing cycles. Soils contaminated with 100 μg g(-1) phenanthrene and 100 μg g(-1) pyrene separately and combined were extracted by 10 g L(-1) surfactant SDBS solution at various times over 120 days. The competitive effect on extraction efficiency may either increase or decrease with increasing soil contact time, depending on the properties of the accessible adsorption sites. The increased difference in extraction efficiency change has a positive correlation with soil organic carbon content. The change in extraction efficiency between no freeze-thawing and freeze-thawing in soils contaminated with both hydrocarbons was smaller compared to it with phenanthrene or pyrene alone due to the similar roles freeze-thawing and competitive effect plays, causing contaminant molecules to occupy the high-energy adsorption sites and expanding the glassy domain of soil organic matter. No general conclusions were obtained among the frequency of freeze-thawing cycles, soil moisture and extraction efficiency. This study validates our previous conceptual freeze-thawing model and is expected to help the development of the environmental fate and risk assessment., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This work was initiated to study the concentration effects on phenanthrene and pyrene extraction during process of aging in phaeozem and burozem with or without freeze-thawing cycles. 1, 10, and 100 μg g(-1) phenanthrene and pyrene contaminated soils were extracted by 10,000 mg L(-1) surfactant SDBS at various times. The extraction amount decreased with increasing contact time. Aging process could be divided into two stages: an initially rapid and then a slow sorption period. The amount extraction of 1 μg g(-1) pyrene in phaeozem was higher at the initial sorption stage. The time for 100 μg g(-1) phenanthrene and pyrene extraction efficiency to reach equilibrium in both soils were shorter than 1 and 10 μg g(-1). Changes in extraction efficiency rate caused by slow sorption were affected by contact time, physicochemical properties of soils and chemicals and the applied concentration of chemicals. For 1 and 10 μg g(-1) phenanthrene and pyrene contaminated soils, freeze-thawing cycle increased the extraction efficiency at the initial 1st and 8th days. The extraction efficiency with no freeze-thawing cycle was higher than that with freeze-thawing cycles at 30 and 120 days. A conceptual model was proposed to account for this process., (Copyright © 2012 Elsevier B.V. All rights reserved.)