Controlling the structure and surface functionality of nano-hydroxyapatite (nHAP) through sustainable strategies remains a significant challenge in heavy metal remediation. This study presents an enzymatic extract-assisted green synthesis method, utilising alginate lyase-digested Sargassum fusiforme extracts (SFEE), to tailor nHAP formation and enhance Cd(II) removal. Incorporation of SFEE results in a plate-like structure with increased specific surface area (127.29 m2/g) and mesoporosity. Among the synthesized materials, SFnHAP-20 demonstrates superior adsorption performance, achieving a maximum capacity of 208.66 mg/g, which is 1.23 times higher than that of conventionally produced CnHAP. Adsorption kinetics follow the pseudo-second-order model, and the equilibrium data best fit the Freundlich isotherm, indicating heterogeneous surface interactions. XPS, FTIR, and structural analyses confirm that Cd(II) removal involves synergistic electrostatic attraction, Ca2+/Cd2+ ion exchange, and surface complexation, with SFEE-derived carboxyl groups providing additional coordination sites. The lower pHpzc (1.82) of SFnHAP-20 further enhances electrostatic binding. The optimized material maintains stable removal performance under real-water conditions, ion interference, and regeneration cycles. These findings demonstrate that enzymatic regulation of marine biomass extracts offers a sustainable approach to developing functional mineral adsorbents for heavy metal removal.

Cereal-legume crop rotations sustainably enhance ecosystem multifunctionality and productivity versus cereal monoculture, yet the microbial mechanisms underlying these changes remain unclear. To address this knowledge gap, we conducted a 6-year field experiment in the North China Plain, comparing two cereal-legume rotations, i. e. wheat-soybean (WS) and wheat-peanut (WP), with a cereal wheat-maize monoculture (WM), focusing on rhizosphere soil biochemistry properties, multifunctionality, bacterial diversity, functional composition, and network complexity. Compared to WM, WS and WP significantly enhanced soil multifunctionality by 199% and 103%, respectively, accompanied by increases in soil organic carbon, total nitrogen, available phosphorus and available potassium contents, as well as microbial biomass carbon and nitrogen. Soil urease, invertase and phosphatase activities, bacterial alpha-diversity, predicted nitrogen-cycle functions and network complexity were highest in WS, lowest in WP, and intermediate in WM. With WM as control, WS had more specifically enriched OTUs (4.1%) than WP (2.7%), with more plant growth-promoting taxa (Bacillus, Adhaeribacter) identified as key multifunctionality predictors. Partial least squares path modelling indicated wheat-soybean rotation enhanced soil multifunctionality via elevating soil fertility, microbial biomass, bacterial network complexity and enzyme activities, while wheat-peanut rotation promoted soil multifunctionality via mainly elevating soil fertility and microbial biomass. Crop-specific root exudates, metabolites, and straw residues drove these microbial divergences. This study highlights that legume rotations enhance soil multifunctionality, with WS outperforming WP, providing insights for optimizing rotations in intensive agriculture.

Bacterial wilt caused by Ralstonia solanacearum compromises the yield and quality of peanut (Arachis hypogaea L.). While rhizosphere microbiome-assisted defense is known, how resistant plant genotypes orchestrate this process remains unclear. Here, we integrate multi-omics analyses of resistant and susceptible peanut genotypes to uncover a genotype-specific defense mechanism. The resistant genotype selectively recruits beneficial bacteria (e.g., Kosakonia and Frankia), which coincides with activated salicylic acid (SA)-dependent systemic acquired resistance (SAR). Crucially, we identify keystone rhizosphere metabolites (including betaine, arginine, and SA) that are positively correlated with both beneficial microbiome assembly and SAR gene expression, establishing a self-reinforcing defense loop. Leveraging these insights, we develop a prebiotic formulation that enhances beneficial microbial recruitment and stimulates SAR. Field trials demonstrate that the prebiotics reduce bacterial wilt incidence from 84.2% to 5.0% and increase yield by 12.9%-20.3%. Collectively, our study reveals a synergistic microbiome-immune co-regulation mechanism in peanut and delivers a translatable solution for sustainable disease management.

Potassium (K) plays important roles in plant growth and development processes, while low K (LK) stress inhibits plant growth by altering reactive oxygen species accumulation. Arbuscular mycorrhizal fungi (AMF) promote nutrient absorption and transport in plants. However, the roles of AMF in affecting K nutrition are less well studied than those of other nutrients, especially in wheat. In this study, the effects of AMF on four wheat varieties were evaluated; results showed that the inoculation with the AMF-Rhizophagus intraradices significantly increased mycorrhizal colonization, fresh and dry weights, ascorbic acid, and glutathione contents, while decreasing malondialdehyde contents under both normal and LK stress treatments. It is worth noting that the contents of K and several nutrient elements were more significantly increased in roots than in shoots, suggesting that AMF mainly affect the uptake of K and other nutrient elements in the roots. Moreover, the expression levels of K transporter genes were higher than those of nitrogen and phosphorus transporter genes, especially under AMF combined with LK stress treatments. These results indicate that AMF improves wheat growth and antioxidant activity by regulating K transporter gene expression and affecting K uptake and transport. Therefore, AMF could be used as a sustainable agricultural alternative in wheat under LK soils.

This study investigates potentially toxic elements (PTEs) concentrations in both washed and unwashed leaves of Calotropis procera and in the soil near its roots along roadsides with varying vehicular traffic densities. Additionally, it explores the plant's physiological, biochemical, and morpho-anatomical responses to PTEs exposure. Samples of unwashed and washed leaves from roadside areas with very high, high, medium, and low traffic densities, as well as control sites located 100-500 m away from roads, were analyzed for PTEs concentrations, physicochemical properties and morpho-anatomical characteristics. A paired sample t-test revealed significant differences (p < 0.05) in PTEs concentrations, except for Mn, with higher levels in unwashed leaves compared to washed ones. The highest PTEs concentrations were observed in areas with very high traffic density (VHD), followed by high-density (HD), moderate (MD), and low-density (LD) areas. The study also explored the role of soil as a sink for these contaminants, revealing a strong positive correlation between vehicular density and PTEs level in soil. The bioaccumulation factor (BCF) indicated significant uptake of Pb, Cd, Cr, Mn, and Cu, with lower values for other elements. The study also assessed physiological and biochemical parameters, including chlorophyll content, ascorbic acid, antioxidant potential, and membrane stability index, all of which showed significant variations across sites with different traffic densities. Morphological and anatomical variations, such as reductions in leaf area, leaf thickness, and stomatal dimensions, were observed in polluted areas. Principal Component Analysis (PCA) highlighted the correlations between PTEs, morphological traits, and vehicular density, with notable negative effects at high traffic sites. In conclusion, C. procera is an effective phyto-accumulator and bioindicator of PTEs pollution, with high ecological adaptability, making it suitable for phytoremediation and pollution monitoring. This study highlights the impact of vehicular pollution on plant health and stresses the importance of monitoring these factors for environmental management.

Industrialization has made the world increasingly unstable, subjecting plants to various constraints. As a consequence, plants are constantly experiencing biological, environmental, and climatic constraints, necessitating defense mechanisms to ensure their survival. Plants are vulnerable to various biotic factors, including insects, pathogens (bacterial, fungal, viral, and nematodes), weeds, and herbivores. They also face different abiotic and climate change challenges such as drought (regulated by genes like GH3, DREB, ZIFL1;3, etc), salinity, heavy metals, metalloids, ultraviolet radiations (UV), ozone (O3), low and high temperature (chilling/cold/freezing/heat), carbon dioxide (CO2), chlorofluorocarbons (CFCs), and flooding/hypoxia/anoxia. Different transcriptional factors, such as KNOX1, PYK10, and NRP1, regulate these abiotic and climate change stresses. Different phytohormones such as auxin (regulated by components AUX/IAA3, PIN, indole-glucosinolate, indole-3-acetaldoxine), gibberellin (key elements involved in the synthesis and signaling such as DELLA, GA3ox, RhHB1), cytokinin (signaling through ARR5), ethylene (involved transcription factors like AP2/ERF), abscisic acid (signaling regulated through SnRK2), salicylic acid, jasmonic acid (regulated by JAZ1/TIFYIOA), brassinosteroids, nitric oxide, and strigolactones (synthetic precursor being GR24) control plants' maturation in normal and stressed conditions by regulating various metabolic and physiological plant activities. Phytohormonal interactions and their synergy are often assessed by different techniques and assays such as CRISPR/Cas9, ELISA, RIA, luciferase, GAL4, and mEmerald GFP. Their synthesis and signaling are regulated by various genes (such as YUCCA1, YUCCA5, GA3ox, etc), transporters (PIN, such as PIN, ABCB, NPF, etc), and receptors (such as PLY4, PLY5, BZR1/BES1, MYC2, etc) and have different precursors such as L-arginine, L-tryptophan, phenylalanine, linolenic acid, S-adenosylmethionine, geranylgeranyl diphosphate. This review comprehensively analyses the breakthrough in phytohormones and their signaling in regulating plants' growth and maturation. Their significance in combating the biotic, abiotic, and climate change stresses, improving stress adaptation to identify novel strategies enhancing plant resilience, sustainable agriculture, and ensuring food security.

As our planet faces increasing environmental challenges, such as biotic pressures, abiotic stressors, and climate change, it is crucial to understand the complex mechanisms that underlie stress responses in crop plants. Over past few years, the integration of techniques of proteomics, transcriptomics, and genomics like LC-MS, IT-MS, MALDI-MS, DIGE, ESTs, SAGE, WGS, GWAS, GBS, 2D-PAGE, CRISPR-Cas, cDNA-AFLP, HLS, HRPF, MPSS, CAGE, MAS, IEF, MudPIT, SRM/MRM, SWATH-MS, ESI have significantly enhanced our ability to comprehend the molecular pathways and regulatory networks, involved in balancing the ecosystem/ecology stress adaptation. This review offers thorough synopsis of the current research on utilizing these multi-omics methods (including metabolomics, ionomics) for battling abiotic (salinity, temperature (chilling/freezing/cold/heat), flood (hypoxia), drought, heavy metals/loids), biotic (pathogens like fungi, bacteria, virus, pests, and insects (aphids, caterpillars, moths, mites, nematodes) and climate change stress (ozone, ultraviolet radiation, green house gases, carbon dioxide). These strategies can expedite crop improvement, and act as powerful tools with high throughput and instant database generation rates. They also provide a platform for interpreting intricate, systematic signalling pathways and knowing how different environmental stimuli cause phenotypic responses at cellular and molecular level by changing the expression of stress-responsive genes like RAB18, KIN1, RD29B, OsCIPK03, OsSTL, SIAGL, bZIP, SnRK, ABF. This review discusses various case studies that exemplify the successful implementation of these omics tools to enhance stress tolerance in plants. Finally, it highlights challenges and future prospects of utilizing these approaches in combating stress, emphasizing the need for interdisciplinary collaborations and bio-technological advancements for sustainable agriculture and food security.

To evaluate the effects of exogenous Si and Zn on the root architecture and physiological effects of maize under Cd stress, a hydroponic experiment was conducted to investigate the effects of 1 mmol·L-1 Si and 100 μmol·L-1 Zn on the growth, photosynthetic system, Cd concentration, absorption kinetics, malondialdehyde （MDA） content, and antioxidant of maize seedlings （Zhengdan 958） under 50 μmol·L-1 Cd stress, which were evaluated using principal component analysis. The results showed that Cd stress significantly inhibited the growth of maize seedlings. The main root length, plant height, and biomass decreased significantly； root development and photosynthetic system were inhibited； and MDA and antioxidant content increased significantly. Under Cd stress, the application of exogenous Si and Zn could effectively reduce the maximum absorption rate of Cd in seedlings and reduce oxidative stress by improving the AsA-GSH cycle, decreasing MDA content, and enhancing photosynthesis, which effectively improved the growth status of maize seedlings. The main root length and plant height were increased by 9.19%-40.88% and 14.35%-18.92%, respectively. The dry weight of the root and shoot were increased by 51.76%-151.76% and 53.11%-84.31%, respectively, and the alleviation effect of Si-Zn interaction on Cd toxicity was slightly better than that of Si or Zn alone. Among them, Si played an important role in inhibiting Cd uptake by maize. The Cd concentration in the underground and aboveground parts was significantly reduced by 43.55% and 80.43%, respectively. The results showed that exogenous application of Si and Zn could alleviate Cd-induced oxidative stress by regulating the content of antioxidant, enhancing photosynthesis, promoting the growth of maize seedlings, and effectively improving the tolerance of maize seedlings to Cd toxicity, which was conducive to the rational utilization of heavy metal-contaminated farmland and food security production.

Presence of the potentially toxic elements (PTEs) is a matter of serious concern when it comes to human health. Most of the previous studies conducted simply quantify the levels of these PTEs in drinking water. Contrary to those studies, the current study is aimed to quantify and correlate the PTEs at source and household levels which counts a novel study in District Swabi. About forty (n = 40) of drinking water samples were collected from six MWDS in Swabi, Pakistan. The physico-chemical parameters, including pH, electrical conductivity (EC), and total dissolved solids (TDS), were measured through Consort electrochemical analyzer Model, C931. PTEs such as Copper (Cu), Lead (Pb), Cadmium (Cd), Zinc (Zn) and Nickel (Ni) were quantified using Perkin Elmer electro-thermal Atomic Absorption Spectrometer (AAS), equipped with graphite furnace. Water Quality Index (WQI) and Hazard Index (HI) were employed to classify the severity of risk. Among the PTEs, Cd and Cr were found in concentrations above the permissible limits of WHO and USEPA. Similarly few of the samples also showed high levels of Pb and Ni. Drinking water of Maini, and Zaida distribution system were classified to be unsafe for consumption based on their WQI values of 1000 and 1814, respectively. Similarly, significant health risk (HI>1) obtained for Children and adults of Shahmansoor and Zaida due to presence of elevated PTEs levels. From findings, it can be assumed that the municipal water distribution systems Swabi district is highly contaminated with PTEs and is a source of serious health risk.

Zinc (Zn), an essential nutrient element, exhibits hormesis in plants-beneficial at low doses but toxic at high concentrations. To understand the molecular mechanisms underlying this hormetic response with low-dose stimulation and high-dose inhibition in wheat, we conducted transcriptomic analysis under different Zn treatments. Low Zn concentration (50 mu M) promoted plant growth by maintaining chlorophyll content, enhancing MAPK signaling, phytohormone signaling, glutathione metabolism, nitrogen metabolism, and cell wall polysaccharide biosynthesis. High Zn concentration (500 mu M) induced ultrastructural damage and suppressed photosynthesis, chlorophyll metabolism, and secondary metabolisms, while upregulating glutathione metabolism. Molecular docking revealed that hydrogen bonds between Zn and antioxidant enzymes facilitated reactive oxygen species scavenging. Notably, exogenous glutathione (GSH) application enhanced wheat tolerance to Zn stress by strengthening the antioxidant defense system and improving photosynthetic capacity. Our findings elucidate the underlying mechanisms of Zn hormesis in wheat and demonstrate the application potential of glutathione in mitigating Zn toxicity, providing strategies for managing Zn-contaminated soils.

As the main producing area of wheat and maize in China, Henan Province produces considerable greenhouse gases during the production and planting processes. Determining the characteristics of carbon and nitrogen footprint changes during the growth process and analyzing the key driving factors will provide a basis for the green production of wheat and maize. Based on the life cycle assessment and LMDI model, the spatio-temporal characteristics, composition change trends, and driving factors of the carbon and nitrogen footprint during wheat and maize production in Henan Province from 2011 to 2020 were systematically evaluated. The results showed that： ① The production cost of wheat was higher than that of maize. ② The carbon footprint per unit area （ CO2-eq ） of wheat and maize in Henan Province was 1.98 t·hm-2 and 1.76 t·hm-2, and the nitrogen footprint per unit area （N-eq ） was 48.28 kg·hm-2 and 28.37 kg·hm-2, respectively. The carbon footprint of wheat and maize in Henan Province showed a fluctuating upward trend, and the nitrogen footprint showed a decreasing trend year by year. ③ Irrigation emissions and NH3 volatilization were the main components of the carbon and nitrogen footprint of wheat and maize, accounting for 28.64 % and 81.27 % of the carbon and nitrogen footprint of wheat and 35.28 % and 82.21 % of the carbon and nitrogen footprint of maize, respectively. ④ The carbon and nitrogen footprints of different cities in Henan Province were different, showing a higher trend in the southeast and a lower trend in the northwest. ⑤ The results of the LMDI model analysis showed that economic factors increased carbon and nitrogen emissions during wheat and maize production, whereas labor and production factors reduced carbon and nitrogen emissions. In summary, to reduce the carbon and nitrogen emissions of agricultural production in Henan Province, we should reduce labor and production costs, develop fertilizer-saving and water-saving technologies, strengthen agricultural science and technology innovation capabilities, and combine policies and economic incentives to promote the development of green and low-carbon agriculture and finally achieve carbon neutrality.

Cadmium (Cd) pollution significantly hampers cleaner production of peanut (Arachis hypogaea L.). Therefore, exploring of tolerance mechanisms to Cd stress and breeding of low-Cd peanut cultivars are urgently needed and require intense efforts. Herein, multi-omics and physiological studies reveal that multiple biological processes, including melatonin (MT) biosynthesis, are involved in the Cd tolerance in peanut plants. Exogenous MT was applied to peanut plants under Cd stress, which decreased Cd accumulation in roots, shoots and seeds for 40%-60%, and promoted the antioxidant capacity. Integrated investigation reveals that MT-mediated Cd tolerance is mainly attributed to the enhanced metabolism of linolenic acid, glutathione (GSH), and phenylpropanoid (lignin), and development of casparian strip in root cell wall. Defense genes, such as non-race-specific disease resistance gene 1/harpininduced gene 1 (NDR1/HIN1)-like in peanut (AhNHL), were also significantly upregulated by MT under Cd stress. Overexpression of the AhNHL gene in tobacco reduced Cd accumulation for 37%-46%, and alleviated photosynthesis-inhibition induced by Cd stress. Transcriptomic analysis suggested that AhNHL confers the Cd tolerance mainly through promoting phenylpropanoid biosynthesis and GSH metabolism. Additionally, exogenous GSH effectively alleviated the Cd stress through improving Cd sequestration and antioxidant capacity in peanut plants, while apply of the GSH biosynthesis inhibitor (buthionine sulfoximine) exacerbated the Cd phytotoxicity. Transcriptomic analysis reveals that exogenous GSH improves Cd tolerance through affecting the expression of genes involved in transcription regulation, and metal ion binding and transport. Our findings provide novel insights into molecular mechanisms underlying Cd tolerance in plants, which would facilitate breeding of low-Cd peanut cultivars.

Co-contamination of soil by cadmium (Cd) and cerium (Ce) has become increasingly prevalent and poses a significant threat to agricultural productivity. To investigate the effects of this joint pollution on plant growth, we investigated the ultrastructural, transcriptomic, and molecular responses of maize seedlings to Cd, Ce, and their mixtures. The results indicated that Cd, Ce, and their mixtures had detrimental effects on maize growth by reducing biomass accumulation (shoot dry weight was decreased by 59.94 %, 37.94 %, and 54.10 %, respectively), disrupting photosynthesis and chlorophyll synthesis, and causing ROS imbalance. However, co-exposure to Cd and Ce resulted in a less severe impact on the maize photosynthetic system compared to Cd treatment alone, as it reduced the production of osmiophilic plastoglobuli. Transcriptomic and molecular docking analyses revealed that Ce enhanced the repair of photosystem II under Cd stress by upregulating chlorophyll-binding proteins and carbon assimilation proteins. SOT5 (Zm00001eb327110) is primarily involved in photosynthesis, ROS scavenging, and phytohormone signaling, which could be crucial for breeding stress-resilient crops. For the first time, we demonstrate that Cd and Ce interacted antagonistically in transcriptomic level. This study provides new insights into how maize responds to heavy metals and rare earth elements and highlights critical pathways for improving stress tolerance.

Wheat is one of the important cereal crops around the world, but it often suffers from abiotic stresses, which threaten food security. Thus, it is critical to identify the genes that determine drought tolerance in wheat. AP2/ERFs are known to regulate drought stress in various crops. In this study, TaERFL1a-overexpressing wheat transgenic lines (TaERFL1a-OEs) were used to determine drought resilience mechanism. After 12 d without watering, the growth phenotype of TaERFL1a-OEs was better than that of the wild type (WT), whose activities of superoxide dismutase and catalase, and contents of ascorbate acid (ASA) and glutathione (GSH) were significantly increased, while malondialdehyde content was significantly decreased. Transcriptome analysis revealed that 28,520 genes were differentially expressed between TaERFL1a-OEs and WT under drought condition. Further analysis found that these DEGs were involved in multiple stress-response processes, especially in the ASA-GSH pathway. qPCR revealed that the expression levels of GPX, DHAR, and MDHAR, which are suggested to be participated in ASA-GSH biosynthesis, were significantly up-regulated in TaERFL1a-OEs under drought stress, especially the DHAR gene. Moreover, dual-luciferase and luciferase complementation imaging revealed that TaERFL1a was more promoted DHAR transcription to a greater extent than other genes. Furthermore, yeast one-hybrid, electrophoretic mobility shift assay, and chromatin immunoprecipitation combined with qPCR revealed that TaERFL1a regulates DHAR expression by binding to the cis-element ERF in DHAR promoter and promotes the transcription of later in vivo and in vitro. Overall, our results provided molecular regulatory evidence for TaERFL1a in wheat drought stress and suggested candidate genes for improving drought-tolerant wheat breeding.

The study examines the toxicity of cadmium (Cd), microplastics (MPs) and their combined pollution on wheat plants, focusing on Cd accumulation and alterations to soil physical and chemical properties. To provide guidance for understanding the physiological and ecological responses of wheat to Cd and MPs contamination. Using a soil pot experiment, the individual and combined impacts of Cd (0 mg kg⁻¹ and 5 mg kg⁻¹) and polyvinyl chloride microplastics (PVC-MPs) (0

Zinc (Zn) stress adversely affects the growth of wheat seedlings. Chitosan (CTS), a growth regulator, can mitigate stress-induced damage in plants. This study aims to investigate the alleviating effects of chitosan on zinc stress in wheat seedlings. A hydroponic experiment was conducted to examine the impact of various concentrations of exogenous chitosan (0, 25, 50, 100, 200, and 400 mg·L−1) on the physiological and biochemical characteristics of wheat seedlings under Zn stress (500 µmol·L−1). Chitosan enhanced biomass accumulation, root morphology, chlorophyll content, photosynthetic parameters, the ascorbate-glutathione (AsA-GSH) cycle, antioxidant enzyme activity, and soluble protein content in wheat seedlings, while reducing malondialdehyde (MDA) levels and Zn translocation to the above-ground parts. Additionally, partial least squares (PLS) analysis identified zinc accumulation as a key factor in wheat seedlings’ response to Zn stress. Specifically, 100 mg·L−1 CTS increased the tolerance index of shoots and roots by 30.59

Abstract Background Lentil is a significant legume that are consumed as a staple food and have a significant economic impact around the world. The purpose of the present research on lentil was to assess the hydrothermal time model’s capacity to explain the dynamics of Lens culinaris L. var. Markaz-09 seed germination, as well as to ascertain the germination responses at various sub-optimal temperatures (T) and water potentials (Ψ). In order to study lentil seed germination (SG) behavior at variable water potentials (Ψs) and temperatures (Ts). A lab experiment employing the hydrothermal time model was created. Seeds were germinated at six distinct temperatures: 15 0С, 20 0С, 25 0С, 30 0С, 35 0С, and 40 0С, with five Ψs of 0, -0.3, -0.6, -0.9, and − 1.2 MPa in a PEG-6000 (Polyethylene glycol 6000) solution. Results The results indicated that the agronomic parameters like Germination index (GI), Germination energy (GE), Timson germination index (TGI), were maximum in 25 0C at (-0.9 MPa) and lowest at 40 0C in 0 MPa. On other hand, mean germination time (MGT) value was highest at 15 0C in -1.2 MPa and minimum at 40 0C in (-0.6 MPa) while Mean germination rate (MGR) was maximum at 40 0C in (0 MPa) and minimum at 15 0C in (-0.6 MPa). Conclusions The HTT model eventually defined the germination response of Lens culinaris L. var. Markaz-09 (Lentil) for all Ts and Ψs, allowing it to be employed as a predictive tool in Lens culinaris L. var. Markaz-09 (Lentil) seed germination simulation models.

This research aimed to clarify the effects of exogenously applied chitosan on the physiological characteristics, antioxidant activities, and Cd accumulation of wheat (Triticum aestivum L.) seedlings under cadmium (Cd) stress and to identify the key indicators based on the partial least squares model. The wheat variety studied was Bainong207 (BN207), and Cd-stress was achieved by growing seedlings in a hydroponic culture experiment with 10 and 25 μmol·L-1 Cd2+ added to the culture solution. It was found that both Cd-stress at 10 and 25 μmol·L-1 significantly inhibited the chlorophyll content, photosynthesis, and biomass accumulation of wheat seedlings. Seedling roots became shorter and thicker, and the lateral roots decreased under Cd-stress. The Cd-stress also increased H2O2 and MDA accumulation and the degree of cell membrane lipid peroxidation and affected the activities of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD). Under Cd stress, exogenous chitosan decreased the Cd content in the aboveground and underground parts of wheat by 13.22 %-21.63 % and 7.92 %-28.32 % and reduced Cd accumulation in the aboveground and underground parts by 5.37 %-6.71 % and 1.91 %-4.09 %, respectively. Whereas exogenous chitosan application significantly reduced the content of H2O2 in roots and aboveground parts of wheat by 38.21 %-47.46 % and 45.81 %-55.73 % and MDA content by 37.65 %-48.12 % and 29.87 %-32.51 %, it increased the activities of SOD and POD in roots by 2.78 %-5.61 % and 13.81 %-18.33 %, respectively. In summary, exogenous chitosan can improve the photosynthetic characteristics and antioxidant enzyme activities of wheat seedlings under Cd stress, reduce the content and accumulation of Cd in the root and aboveground parts of wheat, and alleviate the damage of lipid peroxidation to the cell membrane. All of these results provide the basal data for the application of exogenous chitosan to alleviate Cd toxicity to wheat seedlings.

This research aimed to clarify the mitigative effect of exogenously applied rare earth element cerium(Ce)on the growth,zinc(Zn)accumulation,and physiological characteristics of wheat(Triticum aestivum L.)seedlings under Zn stress.The wheat variety studied was Bainong307(BN307),and Zn stress was achieved by growing seedlings in a hydroponic culture experiment with 500 μmol·L-1 Zn2+added to the culture solution.It was found that Zn stress at 500 μmol·L-1 significantly inhibited the chlorophyll content,photosynthesis,and biomass accumulation of wheat seedlings.Seedling roots became shorter and thicker,and the lateral roots decreased under Zn stress.The Zn stress also increased MDA accumulation and the degree of cell membrane lipid peroxidation and reduced soluble protein contents and the activities of antioxidant enzymes such as superoxide dismutase(SOD),catalase(CAT),and ascorbate peroxidase(APX).On the contrary,exogenous Ce decreased the adsorption and transport of Zn by the root system and alleviated the damage of Zn stress to wheat seedlings.Specifically,the increase in chlorophyll content(chlorophyll a,chlorophyll b,and total chlorophyll)and photosynthetic parameters,the enhancement of antioxidant enzymes activities and soluble protein levels,and the reduction in MDA content and the damage of lipid peroxidation to the cell membrane were all driven by exogenous Ce,which ultimately led to the increase in dry matter biomass of the root system and shoot.In summary,these results provide basic data for the application of exogenous Ce to alleviate Zn toxicity to plants.

Abstract Background The rate of germination and other physiological characteristics of seeds that are germinating are impacted by deep sowing. Based on the results of earlier studies, conclusions were drawn that deep sowing altered the physio-biochemical and agronomic characteristics of wheat (Triticum aestivum L.). Results In this study, seeds of wheat were sown at 2 (control) and 6 cm depth and the impact of exogenously applied salicylic acid and tocopherol (Vitamin-E) on its physio-biochemical and agronomic features was assessed. As a result, seeds grown at 2 cm depth witnessed an increase in mean germination time, germination percentage, germination rate index, germination energy, and seed vigor index. In contrast, 6 cm deep sowing resulted in negatively affecting all the aforementioned agronomic characteristics. In addition, deep planting led to a rise in MDA, glutathione reductase, and antioxidants enzymes including APX, POD, and SOD concentration. Moreover, the concentration of chlorophyll a, b, carotenoids, proline, protein, sugar, hydrogen peroxide, and agronomic attributes was boosted significantly with exogenously applied salicylic acid and tocopherol under deep sowing stress. Conclusions The results of the study showed that the depth of seed sowing has an impact on agronomic and physio-biochemical characteristics and that the negative effects of deep sowing stress can be reduced by applying salicylic acid and tocopherol to the leaves.