Uranium/cadmium (U/Cd) pollution poses a significant global environmental challenge, and phytoremediation offers a sustainable solution for heavy metal contamination. However, the mechanisms by which plants survive U/Cd stress remain unclear. Here, we conducted soil culture experiments of moso bamboo seedlings under U/Cd stress (U, Cd and U + Cd) to examine the effects of it on plant growth, mineral metabolism, and rhizosphere micro-environment. Our findings reveal that U/Cd stress inhibits seedling growth, enhances reactive oxygen species damage, and bolsters the antioxidant system. Additionally, Partial Least Squares Path Modeling (PLS-PM) was employed to uncover potential tolerance mechanisms in moso bamboo under U/Cd stress. U/Cd is mainly distributed in the root cell walls and also exists predominantly in the residual state within the roots. Correspondingly, U and Cd significantly disrupt mineral metabolism in plant. Metabolomic analyses indicate that U/ Cd markedly suppress amino acid metabolism pathways, while they stimulate carbon metabolism to mitigate toxicity. Furthermore, U/Cd stress disrupts the rhizosphere microbial community structure, and the competitive interaction of nitrogen functions exists between rhizosphere microorganism and bamboo roots. PLS-PM reveal the U/Cd stress impacts the interaction of the soil-rhizosphere-plant system. Together, these findings offer new insights into the response mechanism of bamboo plants to heavy metal stress, and provide a theoretical foundation for screening heavy metal tolerant plants and managing mining areas.

In recent years, microplastic (MPs) and pesticide pollution have become prominent issues in the field of soil pollution. This research endeavored to assess the impact of ultraviolet radiation (UV) on the characteristics of microplastics, as well as investigating the toxicological effect on earthworms (Eisenia fetida) when subjected to the dual stressors of microplastics and acetochlor (ACT). This research found that microplastics aged under UV were more prone to wear and tear in the environment, and produced more oxygen-containing functional groups. Chronic exposure experiments were conducted on ACT and aged-MPs. The results revealed that aged-MPs and ACT inhibited earthworm growth, induced oxidative stress, and caused damage to both the body cavity muscles and the intestinal lumen. Compared with individual exposure, combined exposure increased the oxidative products (superoxide dismutase (SOD) and catalase (CAT)) and altered the expression levels of related genes (TCTP and Hsp70) significantly. PE inflicted more significant harm to the earthworm intestinal tissue compared to PBAT. By 1H-NMR metabolomics, the investigation delved into the repercussions of PE and ACT on the metabolic pathways of earthworms. Exposure to ACT and PE can disrupt the stability of intestinal membranes stability, amino acid metabolism, neuronal function, oxidative stress and energy metabolism. Overall, the research revealed that combined exposure of MPs and ACT exacerbated the negative effects on earthworms significantly, and contributed valuable insights to environmental risk assessment of the combined toxicity of microplastics and pesticides.

As emerging pollutants, microplastics (MPs) pose serious threats to the terrestrial ecosystems, and the long-term presence of aged MPs in soil results in toxic effects on plant growth. However, the phytotoxicity mechanisms of aged MPs remain unclear. To understand the toxic effects of aged MPs and the response mechanism of lettuce plants, we selected polyethylene (PE) and polypropylene (PP) (commonly found in soil), and then studied the effects of the two phytotoxins on the soil-plant system before and after aging of the MPs. We found that aging enhanced the toxicity of the MPs to the plants. Compared with the original MPs-treatment group, aged PE and PP particles reduced plant biomasses by 26.19%-28.44% and 25.58%-26.13%, respectively, potentially due to the effects of aged MPs on the rhizosphere soil, which further inhibited nutrient absorption in lettuce. The metabolic response of lettuce to MPs was also different. Aged PE significantly attenuated malic acid and proline concentrations in lettuce, and the reduction in these two products inhibited photosynthesis, energy metabolism, and cellular homeostasis, thereby aggravating the damage caused by aged PE. Aged PP principally affected the metabolic pathways of phenylalanine, tyrosine and tryptophan, which was postulated to be the reason why aging enhanced the phytotoxicity of PP. This study provides new insights into the assessment of the toxic effects of MPs, as well as the environmental behavior and ecological risks of aged MPs.

(3-Hexachlorocyclohexane ((3-HCH) is a persistent organochlorine pesticide that poses a significant threat to the ecological environment, necessitating the urgent development of effective degradation methods. Microbial degradation has demonstrated substantial potential among various bioremediation techniques due to its environmentally friendly and economical characteristics. This study evaluates the degradation capability of Enterobacter sp. CS01 on (3-HCH, its physiological responses, and its potential application in soil remediation. Under optimal conditions (pH 7, 30 degrees C), 51 % of (3-HCH was effectively removed. Metabolomics and antioxidant enzyme activity analyses revealed that CS01 defends against oxidative damage by modulating the activities of superoxide dismutase (SOD) and catalase (CAT), involving butyrate, alanine, aspartate, and glutamate metabolism, as well as the pentose phosphate pathway. CS01 converts (3-HCH into less toxic intermediates through dichloride elimination, dehalogenation of hydrogen, and hydrolysis reactions. Soil experiments indicated that soil enzyme activities (S-POD, S-DHA, S-PPO) are closely related to the degradation of (3-HCH, with the order of carbon source utilization being esters, amino acids, and sugars. This study provides new insights into the microbial degradation mechanisms of organochlorine pesticides and aids in the development of more efficient and environmentally friendly degradation technologies.

Ferroferric oxide nanoparticles (Fe3O4 NPs) are widely utilized as nanoenabled agrochemicals and soil remediation agents, with functional modification significantly enhancing their stability and biocompatibility. However, excessive use of Fe3O4 NPs may pose unassessed ecological risks in soils, particularly concerning the regulatory role of two most common surface modifiers as polyvinylpyrrolidone (PVP) and citric acid (CA) which influence the interactions of NPs with soil organisms and potential toxicity. This study evaluated the nanotoxic effects of bare Fe3O4 NPs (B-Fe3O4 NPs), CA-Fe3O4 NPs, and PVP-Fe3O4 NPs on Eisenia fetida in soil ecosystems. After 7 days of exposure, the B-, CA- and PVP-Fe3O4 NPs decreased the weight of the earthworms, caused oxidative stress and tissue damage. Functional Fe3O4 NPs showed increased accumulation in earthworms while alleviating oxidative stress and homeostatic imbalance by accelerating the activation of related enzymes. Moreover, hyperspectral and pathological observations indicated that CA and PVP modifications effectively alleviated tissue damage caused by Fe3O4 NPs via an improvement in NP biocompatibility, dispersion and stability evidenced by the levels of inositol metabolites, which has been upregulated more significantly by B-Fe3O4 NPs. Significant metabolic disturbances were observed, indicating that functional modifications forced earthworms to adjust amino acid metabolism and consume more energy to detoxify and repair damage. This work supplements the toxic assessment of Fe3O4 NPs and provides crucial insights for optimizing the safety of NPs through functionalization.

Soil salinization threatens global agriculture, reducing crop productivity and food security. Developing strategies to improve salt tolerance is crucial for sustainable agriculture. This study examines the role of organic fertilizer in mitigating salt stress in rice (Oryza sativa L.) by integrating NDVI and metabolomics. Using salt-sensitive (19X) and salt-tolerant (HHZ) cultivars, we aimed to (1) evaluate changes in NDVI and metabolite content under salt stress, (2) assess the regulatory effects of organic fertilizer, and (3) identify key metabolites involved in stress response and fertilizer-induced regulation. Under salt stress, survival rate of the 19X plants dropped to 6%, while HHZ maintained 38%, with organic fertilizer increasing survival rate to 25% in 19X and 66% in HHZ. NDVI values declined sharply in 19X (from 0.56 to <0.25) but remained stable in HHZ (similar to 0.56), showing a strong correlation with survival rate (R-2 = 0.87, p < 0.01). NDVI provided a dynamic, non-destructive assessment of rice health, offering a faster and more precise evaluation of salt tolerance than survival rate analysis. Metabolomic analysis identified 12 key salt-tolerant metabolites, including citric acid, which is well recognized for regulating salt tolerance. HTPA, pipecolic acid, maleamic acid, and myristoleic acid have previously been reported but require further study. Additionally, seven novel salt-tolerant metabolites-tridecylic acid, propentofylline, octadeca penten-3-one, 14,16-dihydroxy-benzoxacyclotetradecine-dione, cyclopentadecanolide, HpODE, and (+/-)8,9-DiHETE-were discovered, warranting further investigation. Organic fertilizer alleviated salt stress through distinct metabolic mechanisms in each cultivar. In 19X, it enhanced antioxidant defenses and energy metabolism, mitigating oxidative damage and improving fatty acid metabolism. In contrast, HHZ primarily benefitted from improved membrane stability and ion homeostasis, reducing lipid peroxidation and oxidative stress. These findings primarily support the identification and screening of salt-tolerant rice cultivars while also highlighting the need for cultivar-specific fertilization strategies to optimize stress resilience and crop performance. Based on the correlation analysis, 26 out of 53 differential metabolites were significantly correlated with NDVI, confirming a strong association between NDVI shifts and key metabolic changes in response to salt stress and organic fertilizer application. By integrating NDVI and metabolomics, this study provides a refined method for evaluating salt stress responses, capturing early NDVI changes and key salinity stress biomarkers. This approach may prove valuable for application in salt-tolerant variety screening, precision agriculture, and sustainable farming, contributing to scientific strategies for future crop improvement and agricultural resilience.

IntroductionGarlic (Allium sativum L.) is renowned for its health-promoting properties, largely due to its sulfur-rich compounds. While copper is essential for plant growth and metabolism, excessive levels can disrupt cellular processes and lead to oxidative stress.ObjectivesThis study aims to investigate the impact of copper supplementation on the metabolic profile of garlic, with a particular focus on changes in sulfur metabolism.MethodsIto garlic cloves were harvested in 2020 on Red-Yellow Latosol soil. Copper chelate fertilizer was applied foliarly at 300 mL/ha, 30, 20, and 10 days before harvest. After harvesting, cloves were refrigerated and analyzed. Using LC-MS metabolomics, the metabolic profile of garlic was analyzed after copper supplementation to assess changes, specifically in sulfur-containing compounds.ResultsCopper supplementation led to a significant reduction in key sulfur-containing metabolites critical for the health-promoting properties of garlic, including allicin (FC = 0.0947), alliin (FC = 0.0147), and gamma-glutamyl-S-allylcysteine (FC = 0.0076). Enrichment analysis identified alterations in pathways related to glutamine, glutamate, alanine, and aspartate metabolism. Additionally, precursors of glutathione (GSH) were depleted, likely as a result of GSH sparing efforts to counteract copper-induced oxidative stress. This redirection may increase susceptibility to ferroptosis, a form of cell death linked to oxidative damage.ConclusionThe metabolomic analysis of copper-supplemented Ito garlic cloves showed a significant reduction in sulfur compounds allicin, alliin, and gamma-glutamyl-S-allylcysteine, important for organoleptic and medicinal properties. This decrease indicates a metabolic shift towards antioxidant defenses, with glutathione being redirected to defense pathways rather than secondary metabolites. Future studies should explore oxidative stress and ferroptosis markers, and lipidomics for a deeper understanding of garlic response to copper exposure.

White clover (Trifolium repens) is an excellent perennial cold-season ground-cover plant for municipal landscaping and urban greening. It is, therefore, widely distributed and utilized throughout the world. However, poor salt tolerance greatly limits its promotion and application. This study aims to investigate the difference in the mechanism of salt tolerance in relation to osmotic adjustment, enzymatic and nonenzymatic antioxidant defenses, and organic metabolites remodeling between salt-tolerant PI237292 (Trp004) and salt-sensitive Korla (KL). Results demonstrated that salt stress significantly induced chlorophyll loss, water imbalance, and accumulations of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2.-), resulting in reduced cell membrane stability in two types of white clovers. However, Trp004 maintained significantly higher leaf relative water content and chlorophyll content as well as lower osmotic potential and oxidative damage, compared with KL under salt stress. Although Trp004 exhibited significantly lower activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, monodehydroasorbate reductase, dehydroascorbate reductase, and glutathione reductase than KL in response to salt stress, significantly higher ascorbic acid (ASA), dehydroascorbic acid (DHA), glutathione (GSH), glutathione disulfide (GSSG), ASA/DHA, and GSH/GSSG were detected in Trp004. These findings indicated a trade-off relationship between antioxidant enzymes and nonenzymatic antioxidants in different white clover genotypes adapting to salt stress. In addition, Trp004 accumulated more organic acids (glycolic acid, succinic acid, fumaric acid, malic acid, linolenic acid, and cis-sinapic acid), amino acids (serine, l-allothreonine, and 4-aminobutyric acid), sugars (tagatose, fructose, glucoheptose, cellobiose, and melezitose), and other metabolites (myo-inositol, arabitol, galactinol, cellobiotol, and stigmasterol) than KL when they suffered from the same salt concentration and duration of stress. These organic metabolites helped to maintain osmotic adjustment, energy supply, reactive oxygen species homeostasis, and cellular metabolic homeostasis with regard to salt stress. Trp004 can be used as a potential resource for cultivating in salinized soils.

The use of nano-chemicals in agriculture has been shown to enhance crop production through soil additions or foliar sprays. However, the accumulation pattern, translocation efficiency, mode of action of nanomaterials (NMs) via different application methods remain unclear. In this study, wheat was treated with CuO-NPs/CeO2NPs (50 and 100 nm) for 21 days using soil and foliar application separately. Foliar spray resulted in higher accumulation and more efficient translocation of NMs compared to soil addition. Smaller NMs exhibited higher accumulation and transfer capabilities under the same application method. The accumulation of CuO-NPs was approximately 20 times greater than that of CeO2-NPs, particularly under the soil addition treatment. Scanning electron microscopy analysis demonstrated that NMs could directly enter wheat leaves via stomata during foliar application. Wheat growth was inhibited by roughly 15 % following CuO-NPs exposure, whereas no significant effects on growth were observed with CeO2-NPs. By integrating nontargeted metabolomics analysis with targeted physiological characteristics assessments, it was revealed that CuO-NPs mainly disturbed nitrogen metabolism pathways and induced oxidative damage. In contrast, CeO2-NPs enhanced carbohydrates related biological processes such as starch and sucrose metabolism, glycolysis, and TCA cycle, which are crucial for carbon metabolism. These findings suggest that the type of nanomaterial is a crucial factor to consider when evaluating their foliar or soil application in agriculture.

Freeze-thaw (FT) aging can change the physicochemical characteristics of microplastics (MPs). The toxic impacts of FT-aged-MPs to soil invertebrates are poorly understood. Here the toxic mechanisms of FT-aged-MPs were investigated in earthworms after 28 d exposure. Results showed that FT 50 mu m PE-MPs significantly increased reactive oxygen species (ROS) by 5.78-9.04 % compared to pristine 50 mu m PE-MPs (41.80-45.05 ng/mgprot), whereas FT 500 mu m PE-MPs reduced ROS by 7.52-7.87 % compared to pristine 500 mu m PE-MPs (51.44-54.46 ng/ mgprot). FT-PP-MPs significantly increased ROS and malondialdehyde (MDA) content in earthworms by 14.82-44.06 % and 46.75-110.21 %, respectively, compared to pristine PP-MPs (40.56-44.66 ng/mgprot, 0.41-2.53 nmol/mgprot). FT-aged PE- and PP-MPs caused more severe tissue damage to earthworms. FT-aged PE-MPs increased the alpha diversity of the gut flora of earthworms compared to pristine MPs. Earthworm guts exposed to FT-aged-MPs were enriched with differential microbial genera of contaminant degradation capacity. FT-PE-MPs affected membrane translocation by up-regulating lipids and lipid-like molecules, whereas FTPP-MPs changed xenobiotic biodegradation and metabolism by down-regulating organoheterocyclic compounds compared to the pristine PE- and PP-MPs. This study concludes that FT-aged MPs cause greater toxicity to earthworms compared to pristine MPs.