Chromium (Cr), a pervasive and toxic heavy metal contaminant of agricultural soils, poses a significant threat to crop productivity and food safety. Silicon nanoparticles (Si-NPs) represent a promising nano-enabled strategy for mitigating heavy metal toxicity in plants. However, the molecular mechanisms by which Si-NPs confer Cr tolerance in major crops such as Brassica napus are not fully elucidated. This study investigated the physiological and transcriptomic responses of B. napus to Cr stress and the protective role of Si-NPs. We found that Si-NPs application significantly improved plant growth and biomass while reducing Cr translocation to shoots. Physiologically, Si-NPs alleviated Cr-induced oxidative stress by enhancing antioxidant defense and reducing reactive oxygen species and lipid peroxidation. RNA-seq analysis revealed that Cr stress profoundly dysregulated genes involved in metal transport, oxidative response, and phenylpropanoid biosynthesis. Crucially, Si-NPs induced a protective transcriptional reprogramming, upregulating genes associated with metal chelation and sequestration (e.g., metallothioneins, ABC transporters), antioxidant enzymes, and the biosynthesis of lignin and flavonoids. These changes are consistent with enhanced metal detoxification and reinforced cell walls, effectively reducing Cr mobility and toxicity. Our findings decipher the key molecular pathways through which Si-NPs enhance Cr tolerance in B. napus, providing crucial insights for developing Si-NP-based strategies to cultivate crops in Cr-contaminated environments.

Lead (Pb) contamination in agricultural soils reduces crop productivity and threatens food safety, highlighting the need for in situ amendments that lower Pb bioavailability while supporting soil functioning and plant performance. This study upgraded poultry manure-derived biochar through microwave activation and genipin-crosslinked chitosan modification (MPBCH), then evaluated its performance in a greenhouse pot experiment with Brassica napus grown in field-collected Pb-contaminated soil. Six treatments were compared: untreated Pb-stressed soil (CK), chitosan (CH), poultry manure biochar (PBC), microwave-prepared biochar (MPBC), chitosan-modified PBC (PBCH), and MPBCH. The MPBCH produced the strongest overall response, increasing soil pH from 5.84 to 6.95 and reducing DTPA-extractable Pb by 62.0%. Root and shoot Pb concentrations decreased by 52.1% and 57.9%, respectively, while immobilization-related indices consistently indicated lower Pb mobility and restricted soil-to-plant transfer. MPBCH also increased β-glucosidase, phosphomonoesterase, catalase, and urease activities by 43.74%, 40.22%, 60.24%, and 40.48%, respectively. Rhizosphere bacterial analysis showed the highest Shannon diversity (4.52) and Chao richness (1882.12) under MPBCH, with clear community separation in principal coordinates analysis, significant divergence by PERMANOVA (F = 3.73, R2 = 0.599, p = 0.0005), and enrichment of bacterial biomarkers. These belowground responses coincided with improved biomass, photosynthetic pigments, gas-exchange traits, nutrient status, antioxidant defense, and lower oxidative stress markers. Transcriptomic and qRT-PCR analyses supported reduced Pb-stress status under MPBCH, with shifts in carbon metabolism, glutathione metabolism, photosynthesis, and metal transport-related genes. Multivariate integration identified MPBCH as the strongest-performing treatment across the measured Pb immobilization, plant physiological, and soil biochemical responses.

Drought stress poses a significant threat to rapeseed (Brassica napus) productivity. This study investigates the efficacy of calcium nanoparticles (Ca-NPs) in mitigating drought stress, with a specific focus on the proteomic reprogramming that underlies this resilience. Physiological assessments confirmed that Ca-NP application restored plant growth and biomass under drought conditions, correlating with enhanced photosynthetic efficiency and a potentiated antioxidant response. A pivotal and novel finding, revealed through non-invasive micro-test technology (NMT), was that Ca-NPs prevented drought-induced pathological leakage of cellular Ca²⁺, thereby stabilizing membrane integrity and suggesting a primed state for stress signaling. Quantitative proteomic analysis (TMT-based) identified significant alterations in the abundance of key proteins involved in central metabolic processes. Specifically, Ca-NPs upregulated proteins associated with carbon fixation, porphyrin and chlorophyll metabolism, and the glutathione-mediated antioxidant pathway, providing the first comprehensive proteomic evidence of a reconfiguration of primary and defensive metabolism in rapeseed under Ca-NP treatment. Furthermore, weighted protein co-expression network analysis (WGCNA) identified highly connected hub proteins within modules strongly correlated with improved physiological traits, pinpointing critical functional components of the drought response. These findings demonstrate that Ca-NPs do not merely alleviate symptoms but actively prime rapeseed plants by enforcing ionic homeostasis and orchestrating a protective proteomic landscape, positioning them as a powerful nano-priming strategy for sustainable agriculture. Moreover, exogenously applied Ca-NPs can be further used for rapeseed seed coating. The coated seeds are then applied in the precision drill-seeding of rapeseed, jointly promoting the increase in large-scale per-unit yield of rapeseed.

The application of nanotechnology in agriculture offers promising solutions to enhance crop resilience against drought, a major constraint to global agricultural productivity. This study investigated the role of foliar-applied calcium nanoparticles (Ca-NPs; 100 mg L⁻¹) in modulating drought responses in rapeseed (Brassica napus L.), using the drought-tolerant genotype ZD622 under drought conditions (10

Anthocyanins are flavonoid compounds that provide plants with various advantages, including resistance to abiotic stress, pollinator attraction, and antioxidant properties. The present study aimed to investigate the impact of anthocyanin accumulation on drought tolerance in two genotypes of Brassica napus; purple-leaf (PL) and green-leaf (GL). Transcriptomic, metabolomic, and physiological analyses were conducted under drought conditions induced by polyethylene glycol (PEG-6000) for 4 and 8 days, with an additional evaluation after 4 days of re-watering. After drought stress, the PL genotype showed higher anthocyanin content, relative water content, and total soluble sugar compared to the GL genotype. Furthermore, the PL genotype exhibited reduced levels of reactive oxygen species, higher antioxidant enzyme activities, and less damage to the chloroplast ultrastructure than the GL genotype. These results indicate that the PL genotype shows significant advantages over GL, demonstrating improved water holding capability and stress tolerance. Moreover, under mild drought and re-watering conditions, the PL genotype of B. napus exhibited significant upregulation of structural genes expression associated with the biosynthesis of flavonoids. These correlate with increased anthocyanin content, particularly cyanidin glycosides and flavanols. The PL genotype showed greater gene expression related to flavonoid biosynthesis, particularly anthocyanin production, compared to GL. Alongside, PL accumulated higher levels of anthocyanin-related metabolites. These results suggest that the enhanced flavonoid production contributes to greater drought resistance in PL. Additionally, by identifying important genes and metabolites related to anthocyanin accumulation and drought response, this integrated study provides insights into the intricate regulatory network that underlies these processes. These findings emphasize the potential of PL as a valuable genetic resource for developing drought-resistant rapeseed cultivars.

Brassica napus is a key oilseed crop with potential for cultivation in contaminated soils. However, the molecular mechanisms underlying chromium (Cr) toxicity and tolerance are not well-defined. This study aimed to elucidate these mechanisms by analyzing two contrasting cultivars, ZS758 and ZD622, under 50 mu M Cr stress using a hydroponic experiment for physiological assessments, transcriptomics, and metabolomics. Cr exposure significantly increased tissue Cr content and severely inhibited plant growth, photosynthesis, and mineral nutrient uptake. Multi-omics analysis revealed extensive transcriptional and metabolic reprogramming. Specifically, we identified 15,882 and 13,371 differentially expressed genes (DEGs) and 256 and 136 differentially expressed metabolites (DEMs) identified in ZS758 and ZD622, respectively. These changes were primarily enriched in carbohydrate and amino acid metabolism pathways. The tolerant cultivar ZS758 exhibited more robust activation of defense-related pathways, including cell wall biosynthesis, hormone signaling, and transporter activity. Our integrative analysis reveals that Cr tolerance in rapeseed associated with cultivar-specific physiological and molecular adaptations. These insights provide potential targets and pathways for developing Cr-resistant varieties for sustainable agriculture in contaminated environments.

Untreated effluents from the pottery industry pose ecological and human health risks by polluting soil, food crops, and groundwater with cadmium (Cd). Arbuscular mycorrhizal fungi (AMF) and easily extractable glomalin (EG) secreted by AMF can immobilize Cd in soil and minimize its migration to food crops and groundwater. This study hypothesized that applying EG and AMF together in Cd-polluted soil may result in their synergistic crosstalk. This synergism can reduce Cd migration from soil to plants and groundwater, and improve plant traits and soil health compared to the sole application of AMF and EG. This pot study investigated a novel idea: amending pottery Cd-polluted soil with sole AMF inoculum, EG, and AMF + EG. Later, Cd bioavailability in soil and its migration in pea plants and leachates, as well as plant growth and yield, grain nutrition, and activities of soil enzymes, were examined. A synergistic interaction between AMF and EG occurred in the AMF + EG treatment, which reduced the concentrations of bioavailable Cd in soil, plant shoots, roots, and grain by 64

Conventionally prepared biochar (BC) composites with zero-valent iron (nZVI) may not efficiently immobilize nickel (Ni) due to poor nZVI retention in pores. Conversely, BC prepared with microwave system (MWB) exhibits better porosity for impregnating nZVI, resulting in superior Ni immobilization. This study investigates the effects of sole BC, MWB, and nZVI, combining nZVI with BC (BC+nZVI) and MWB (MB+nZVI) as well as nZVIimpregnated BC (BCnZVI) and MWB (MBnZVI) on Ni immobilization in soil and its uptake in Brassica napus. The amendment's effects on plant growth, photosynthesis, antioxidant enzymes, and soil health were also scoped. Compared to control (CK-Ni), MBnZVI maximally reduced Ni bioavailability in soil (58 %) and its concentrations in plant shoots (89 %) and roots (70 %) by raising soil pH (0.85 unit), forming insoluble Ni compounds and high surface reactivity. Interestingly, shoot and root dry weight increased by 213 % and 212 %, while photosynthetic parameters, i.e., Pn, Tr, Gs, and Ci, increased by 98 %, 69 %, 66 %, and 117 %, respectively, under MBnZVI treatment compared to CK-Ni. The MBnZVI improved the abundance of microbial phyla (Firmicutes, Actinobacteria, Proteobacteria, Nitrospirae, Bacteroidetes, and Gemmatimonadetes) and raised catalase, beta-glucosidase, urease, cellobiohydrolase, and saccharase activities in soil by 88 %, 180 %, 93 %, 78 %, and 71 %, respectively, than CK-Ni. MBnZVI, compared to CK-Ni, enhanced the activity of antioxidants, including CAT (181 %), APX (101 %), SOD (108 %), POD (161 %), DHAR (128 %), and GST (138 %) in plants. Upregulation in antioxidants and downregulation in Ni transporter genes were found in plants with MBnZVI. Conclusively, MBnZVI can remediate Ni-contaminated soils and improve plant growth.

Food security is threatened by global warming, which also affects agricultural output. Various components of cells perceive elevated temperatures. Different signaling pathways in plants distinguish between the two types of temperature increases, mild warm temperatures and extremely hot temperatures. Given the rising global temperatures, heat stress has become a major abiotic challenge, affecting the growth and development of various crops and significantly reducing productivity. Brassica napus, the second-largest source of vegetable oil worldwide, faces drastic reductions in seed yield and quality under heat stress. This review summarizes recent research on the genetic and physiological impact of heat stress in the Brassicaceae family, as well as in model plants Arabidopsis and rice. Several studies show that extreme temperature fluctuations during crucial growth stages negatively affect plants, leading to impaired growth and reduced seed production. The review discusses the mechanisms of heat stress adaptation and the key regulatory genes involved. It also explores the emerging understanding of epigenetic modifications during heat stress. While such studies are limited in B. napus, contrasting trends in gene expression have been observed across different species and cultivars, suggesting these genes play a complex role in heat stress tolerance. Key knowledge gaps are identified regarding the impact of heat stress during the growth stages of B. napus. In-depth studies of these stages are still needed. The profound understanding of heat stress response mechanisms in tissue-specific models are crucial in advancing our knowledge of thermo-tolerance regulation in B. napus and supporting future breeding efforts for heat-tolerant crops.

Microplastic pollution has emerged as a critical environmental concern, particularly in agricultural soils, where various MP types, including polyethylene, polystyrene and polyvinyl chloride accumulate due to plastic mulch degradation, irrigation, and biosolid application. This review synthesizes current knowledge on the impacts of MPs on soil integrity and function, highlighting the degradation of soil structure, disruption of nutrient cycles and shifts in microbial community composition and enzymatic activity. Furthermore, MPs can be taken up by plants, with submicrometer sized particles infiltrating root tissues, triggering phytotoxic effects such as oxidative stress, impaired growth, and reduced photosynthesis. In response plants deploy tolerance mechanisms involving antioxidant defense and altered nutrient metabolism to mitigate MP-induced stress. Advanced omics technologies, including transcriptomics, metabolomics, and proteomics provide valuable insights into the molecular responses of plants to MP exposure, uncovering stress responsive genes, metabolite shifts and protein alterations linked to MP toxicity. This review synthesizes current knowledge on MP contamination in agricultural soil, its impact on soil health and plant physiology, and the application of multiomics approaches to elucidate MP-induced toxicity, paving the way for sustainable strategies to mitigate MP pollution in agroecosystems.

Cadmium (Cd) toxicity negatively impacts plant health and productivity. Nanosilica (SiO2NPs) and salicylic acid (SA) enhance plant performance and alleviate heavy metals stress. Yet, their combined effects against Cd-toxicity in rice remained less-explored. Thus, a hydroponic study investigated the individual and combined effects of SiO2NPs and SA on Cd-stress mitigation in rice at physio-biochemical, cellular, and molecular levels. Results indicated that Cd-alone treatment caused a significant reduction in rice growth and biomass and photosynthetic efficiency, which was associated with oxidative damage caused by enhanced Cd-accumulation in plant tissues. Cd-induction also potentiated its phytotoxicity by triggering enzymatic antioxidants against the extra production of reactive oxygen species (ROS). The addition of SiO2NPs and/or SA markedly minimized the Cd-induced toxicity by reducing Cd-bioaccumulation (42-56%), protecting photosynthetic efficiency, which were directly correlated with seedling biomass and restored cellular structures (leaf ultrastructure and surface morphology). The combined application of SiO2NPs and SA was more effective in activating antioxidant enzymes, phytohormones biosynthesis, and reducing oxidative damages caused by Cd than sole application. This was evident in the decreased production of ROS, malondialdehyde contents (29-37%), and recovered membrane stability. Moreover, SiO2NPs and/or SA relieved Cd-bioaccumulation (41-56%) by downregulating the Cd-related transporter genes (OsNramp1, OsNramp5, OsHMA2, and OsHMA3). Altogether, the cellular Cd-accumulation, photosynthesis, antioxidant defense, and phytohormones against oxidative stress can be ideal markers for cultivating rice in Cd-contaminated soils.

This study investigates the physiological, biochemical, and molecular responses of two Brassica napus (B. napus) cultivars, ZD622 and ZD630, exposed to arsenic (As) stress. ZD630 was more resistant to As-induced toxicity, as demonstrated by higher biomass retention, less chlorophyll degradation, and less impairment of photosynthetic activity than ZD622. Photosynthetic parameters like as Pn and chlorophyll fluorescence were less influenced in ZD630, indicating a higher resilience in maintaining photosynthetic machinery integrity. Ultrastructural study demonstrated that ZD630 caused less damage to cellular components such thylakoid membranes and mitochondria. Moreover, ZD630 more efficient As exclusion mechanism, as seen by decreased arsenic accumulation in aerial tissues, led to its higher stress performance. Comparative transcriptome analysis was conducted to further dissect the molecular mechanisms underlying these morpho-physiological traits. KEGG pathway analysis revealed that the pathways for photosynthesis, auxin signaling, and amino acid metabolism were overrepresented suggesting these pathways may play important roles in the differential response to As between the two cultivars. ZD630 revealed activation of genes related to photosystem II repair, auxin transport, MAPK signaling, and ABA receptors, which might contribute to its improved stress response. Additionally, the differential control of cysteine and methionine metabolism contributes to ZD630 improved capacity to detoxify As via glutathione production.

The light-harvesting chlorophyll a/b-binding proteins (Lhcb) are an essential component of the photosynthetic antenna system, playing a critical role in both photosynthesis and the regulation of plant stress responses. In the rapeseed (Brassica napus L.) genome, we identified eight BnaLhcb genes, which were phylogenetically classified into three distinct groups. These genes exhibited a significant level of structural conservation and were distributed across ten chromosomes. Given the established role of Lhcb genes in abiotic stress defense, we investigated their response to chromium (Cr) stress in both Cr-tolerant and Cr-sensitive rapeseed cultivars. Notably, the expression of BnaLhcb5.3 was significantly downregulated in the sensitive cultivar and upregulated in the tolerant one, indicating its potential role in Cr stress adaptation. The BnaLhcb5.3 cDNA was successfully cloned, and its subcellular localization was confirmed to be within the chloroplast. Functional characterization using transgenic Arabidopsis plants overexpressing BnaLhcb5.3 demonstrated enhance in Cr tolerance, improved plant growth, and biosynthesis of photosynthetic pigments. These plants also exhibited superior gas exchange parameters, higher activities of photosystem I (PSI) and photosystem II (PSII), and reduced ROS accumulation due to a strengthened antioxidant enzymatic defense system under Cr stress. Overall, our results demonstrated that BnaLhcb5.3 plays a vital role in modulating growth responses and is a key factor in enhancing Cr tolerance in rapeseed.

Cadmium (Cd) contamination threatens agroecosystems and food security by degrading soil health, inducing plant oxidative stress, and reducing crop yields. Sustainable strategies integrating biochar (BC) with nanoparticles (NPs) for Cd immobilization and soil-plant-microbe restoration remain underexplored. Here, we demonstrate the efficacy of BC, nano-silicon (nSi), and nano-iron (nFe) to immobilize Cd, improve soil health and reprogram maize stress responses in Cd-contaminated soil. Soil Cd bioavailability, microbial networks, and maize transcriptomes were analyzed under varying BC-nSi-nFe formulations. Among these formulations, the BC + 25 % nSi + 75 % nFe + Cd (T6) composite reduced bioavailable Cd by 21 %, raised soil pH from 6.21 to 6.98, and enhanced soil enzyme activities (118-139 %). T6 improved maize biomass (115-119 %), reduced shoot Cd accumulation (78 %), and suppressed oxidative stress (67-75 % ROS reduction). This study presents transcriptomic evidence showing that BC-NPs composites mitigate Cd stress and modulate maize antioxidant defense and phytohormone signaling pathways, offering new insights into the molecular mechanisms underlying improved plant resilience. Soil microbial networks shifted toward metal-resistant taxa, with enriched glutathione metabolism and nitrogen fixation. BC-NPs composites offer a multidimensional remediation strategy, integrating nanomaterial science, microbial ecology, and plant molecular biology to mitigate Cd toxicity. This approach enhances soil-plant resilience, supporting sustainable agriculture in contaminated ecosystems.

A cutting-edge smart nano-hybrid technology, offering potential benefits for plants, has recently been developed to address the pervasive issue of heavy metal pollution. This study explored the potential of this technology in mitigating chromium (Cr) stress in rapeseed using a nano-based system that integrates 100 μM hydrogen sulphide (H2S) and 50 μM manganese nanoparticles (Mn-NPs). This strategy reveals Cr-stress tolerance mechanisms through physiological assessments and transcriptome data analysis. The results demonstrated that Cr stress substantially inhibited rapeseed growth while increasing oxidative damage markers (MDA and ROS levels). Conversely, Mn-NP and H2S co-treatment significantly mitigated these effects, as shown by: (1) restored growth metrics, (2) improved photosynthetic performance and membrane integrity, (3) optimized Mn/H2S homeostasis, and (4) reduced tissue Cr accumulation. The reduction in Cr content was attributed to enhanced Cr-detoxification mechanisms, driven by the upregulation of enzymatic antioxidant activities, like superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase. Transcriptomic profiling revealed marked upregulation of genes involved in core metabolic processes, including photosynthetic pathways, carbon assimilation, secondary metabolite biosynthesis, inositol/phosphatidylinositol signalling systems, and stress-response networks. Under Cr stress, Mn-NP and H2S co-treated rapeseed plants displayed enhanced tolerance, highlighting the crucial role of these signalling agents in activating Cr-defence mechanisms. Our findings demonstrate that the integration of nanotechnology and gasotransmitter signalling molecule H2S presents a novel strategy for enhancing heavy metal tolerance and plant productivity in contaminated soils.

Brassica napus is a biennial crop that is widely used for biofuel, fodder, and oil. Current study indicates that B. napus has a great potential for growth in marginal soils polluted with heavy metals. Transcriptome profiling of putative genes associated with chromium (Cr) absorption, transport, and accumulation in B. napus was used to study the molecular mechanism of plant resistance to 50-µM Cr stress. The results demonstrated significant reductions in morphological and physiological attributes, changes in related gene profiles, cell structural damage, and downregulation of photosynthesis-associated genes. Furthermore, the plants showed the ability to recover from Cr-induced damage by controlling Cr uptake and maintaining redox balance in photosynthesis under stressful conditions. Following the Cr treatment, plant roots absorbed high Cr and stored it in cell walls, to decrease the absorption to aboveground plant parts. Under Cr treatment, 2401 differentially expressed genes (DEGs) were identified. Cr-induced DEGs were related to photosynthesis, metal–ion chelation, and heavy-metal transport. Co-expression and weighted correlation network analysis revealed the relevance of ABC transporter pathways and glutathione metabolism in B. napus Cr tolerance. This study has the potential to provide a molecular and genetic basis for the validation of future candidate genes and the breeding of crops with similar properties.

Nanotechnology has been widely used in agriculture to improve plant growth and stress tolerance. Exogenous application of calcium nanoparticles (CaO NPs) can improve plant tolerance to drought stress. However, underlying...