Cadmium (Cd) pollution leads to reduced crop yields and poses a threat to human health, making it an important environmental and agricultural safety issue. Selenium [Se(V)] has been shown to alleviate Cd stress in plants; however, the mechanisms underlying Se-mediated protection against Cd toxicity remain largely unclear. In this study, we investigated the physiological and molecular mechanisms of Se(W)-alleviated Cd toxicity in strawberry plants through physio-biochemical and transcriptomic analyses. Our results showed that foliar spraying with Se (IV) increased photosynthetic efficiency, reduced Cd-induced oxidative damage by enhancing antioxidant enzyme activities and soluble sugar contents, thereby improving Cd stress tolerance. Transcriptomic profiling revealed 477 common differentially accumulated transcripts (DATs), predominantly enriched in transporter activity, oxidoreductase function, and antioxidant-related processes. Notably, seven key genes involved in Cd efflux, chelation, secondary metabolite transport and nutrient uptake (FvPCR9-like, FvCBP-like, FvWATI-like, FvMOT1, FvY1476gO214O, FvNR12.1 and FvZIP8) exhibited opposite expression patterns under Se(W) and Cd treatments. Supplementation with Se(IV) also modulated phytohormone signaling, nitrogen metabolism and carbon metabolism pathways, providing a multi-dimensional approach to mitigating Cd-induced physiological disruptions. This study provides novel insights into Se(IV)-mediated Cd stress adaptation, and offers promising strategies for developing low-Cd-accumulating crops, addressing critical environmental and agricultural challenges associated with heavy metal contamination.
Throughout history, plant diseases have posed significant challenges to agricultural progress, driven by both abiotic and biotic factors. Abiotic factors include wind, salt damage, freezing, girdling roots and compacted soil, while biotic factors encompass bacteria, nematodes, fungi and viruses. Plants have evolved diverse defense strategies to counter pathogen attacks, one of which involves chitinases, a subset of pathogenesis-related proteins. Chitinases are hydrolytic enzymes that degrade chitin, a high-molecular-weight linear polymer of N-acetylD-glucosamine, which is a crucial component of fungal cell walls and septa. These enzymes are produced by a wide range of organisms, including plants, animals, insects, fungi and microorganisms. In plants, chitinases are strongly expressed under pathogenic stress, primarily targeting fungal pathogens by breaking down their cell walls. They also contribute to cell wall remodeling and degradation during growth and defense processes. Numerous studies have demonstrated that the antifungal activity of chitinases is influenced by the chitin concentration and surface microstructure of different fungal species. Research has highlighted their role in protecting plants like mango, cucumber, rye, tomato, grapevine and other plants from various fungal diseases. These findings underscore the critical role of chitinases in plant defense mechanisms, showcasing their importance in mitigating fungal infections and supporting plant health.
This study investigates the potential of green-fabricated manganese dioxide (MnO2) nanoparticles (NPs) to mitigate chromium (Cr) toxicity in wheat, presenting a novel approach to enhancing ion homeostasis and physiological resilience under Cr stress. Chromium contamination in agricultural soils is a significant concern, severely impacting crop productivity and disrupting the physiological homeostasis of wheat. Chromium exposure compromises nutrient uptake, induces oxidative stress, and impairs plant growth and yield. This study explored the use of green-fabricated MnO2NPs to mitigate Cr-induced oxidative stress in two bread wheat cultivars, Borlaug-16 and SKD-1. Seed nano-priming with MnO2NPs (100, 250, and 500 mg kg-1) was applied, followed by Cr (100 mg kg-1) exposure, and key physiological, biochemical, and ionomic responses were evaluated. Manganese dioxide nanoparticles significantly reduced Cr uptake and improved ion transport. In Borlaug-16, NP250 enhanced seedling height by 74 %, while NP100 reduced H2O2and TBARS by 60.28 % and 50.17 %, respectively, indicating improved oxidative stress tolerance. SKD-1 exhibited greater Cr stress tolerance, with NP250 improving root length by 31.03 % and relative water content by 56.66 %, supporting better water retention. Additionally, MnO2NP treatments boosted antioxidant enzyme activities, increasing APX and GPX by up to 12.47 %, and restored root and leaf anatomy, reversing Cr-induced structural damage. Furthermore, MnO2NPs enhanced the uptake of essential nutrients such as calcium, potassium, and magnesium, while restricting Cr translocation, improving overall nutrient efficiency. These findings emphasize the potential of MnO2NPs as an eco-friendly strategy for enhancing crop resilience and promoting sustainable agriculture in Cr-contaminated soils.
Fusarium graminearum poses a major threat to barley production worldwide. While seed priming is a promising strategy to enhance plant defense, the use of unconventional priming agents remains underexplored. This study investigates the protective effects of pre-infection camel urine seed priming on barley seedlings challenged with Fusarium graminearum, focusing on growth, disease resistance, oxidative stress, and defense-related responses. Barley grains were primed with camel urine and grown in both Fusarium-infested and uninfested soils. Fusarium infection initially triggered a sharp increase in oxidative stress markers reflecting an early oxidative burst commonly associated with defense signaling. However, in hydro-primed seedlings, this response persisted, leading to sustained oxidative damage and growth suppression. In contrast, camel urine priming modulated the oxidative burst effectively, initially permitting H2O2 accumulation for defense activation, followed by a rapid decline, resulting in an 84.53 % reduction in disease severity and maintenance of seedling growth under infection. This was accompanied by enhanced antioxidant defenses, as indicated by significantly increased activities of antioxidant enzymes, and a 145 % increase in total antioxidant capacity compared to control. Camel urine priming also showed a reduction in shikimic acid levels under infection, suggesting increased metabolic flux toward the phenylpropanoid pathway. Thus, phenylalanine ammonia-lyase activity, phenolic compounds, and flavonoids were significantly elevated. Antifungal enzymes, beta-glucanase and chitinase, also remained high in camel urine-primed seedlings, in contrast to their sharp decline in hydro-primed controls. These findings highlight camel urine priming as a promising, sustainable approach for managing Fusarium in barley.
Cadmium (Cd) contamination in agricultural soils poses a serious threat to crop productivity and food security, necessitating effective mitigation strategies. This study investigates the role of silicon nanoparticles (SiNPs) in alleviating Cd-induced stress in maize (Zea mays L.) under controlled greenhouse conditions. Sterilized maize seeds were sown in sand-filled pots and treated with varying SiNP concentrations (0%, 0.75%, 1.5%, 3%, and 6%) with or without Cd (30 ppm). Physiological, biochemical, and antioxidant parameters were analyzed to assess plant responses. Results demonstrated that SiNPs significantly enhanced photosynthetic pigment concentrations, with chlorophyll-a, chlorophyll-b, and carotenoids increasing by 45%, 35%, and 50%, respectively, in the 6% SiNP + 30 ppm Cd treatment. Biochemical analyses revealed improved osmotic adjustment, as indicated by higher soluble protein (6.52 mg/g FW) and proline (314.43 mu mol/g FW) levels. Antioxidant enzyme activities, including superoxide dismutase, catalase, and ascorbate peroxidase, were markedly higher in SiNP-treated plants, mitigating oxidative damage. Additionally, SiNPs reduced Cd accumulation in plant tissues, suggesting a protective role in limiting metal toxicity. These findings highlight SiNPs as a promising approach for enhancing maize resilience against Cd stress, with potential applications in sustainable agriculture for improving crop health in contaminated soils.
Soil-borne pathogens can severely reduce vegetable crop output and quality. A disease complex may develop when many soil-borne pathogens attack a crop simultaneously, which can cause more damage. The soil-borne fungus Fusarium oxysporum (Fo) and the nematode Meloidogyne incognita (Mi) significantly reduce global tomato (Solanum lycopersicum L.) yields. After a soil-borne pathogenic infection, plants undergo numerous changes. Therefore, we conducted the present study to examine the impact of soil-borne pathogens Fo and Mi on the growth, physiology, biochemical, and root morphology of tomato cultivars Zhongza 09 (ZZ09) and Gailiang Maofen 802 (GLMFA and GLMFB) at 10, 20, and 30 days after-inoculation (DAI). The present study revealed that combined infections adversely damaged plant growth, photosynthetic pigmentation, gas exchange, biochemistry, and root morphology. The plant growth reduction in GLMFA and GLMFB was greater than in ZZ09. The chlorophyll content and photosynthetic indices declined dramatically; however, ZZ09 declined less than GLMFA and GLMFB plants. In GLMFA and GLMFB plants, the combined infection of Fo and Mi lowered plant-defense-related antioxidant activity compared to their single infection or control. ZZ09's antioxidants were greatly up-regulated, indicating pathogen tolerance. ZZ09 had significantly lower gall and wilt disease indices than GLMFA and GLMFB. Moreover, the microscopic examination of roots showed that Fo and Mi infection damaged GLMFA and GLMFB more than ZZ09 plants. Thus, combined infection induced severe root damage, reduced plant growth, reduced antioxidants, and increased reactive oxygen species (ROS) production compared to single inoculation. However, the ZZ09 cultivar exhibited significantly stronger tolerance to combined infection.
Arsenic (As) contamination in soil represents a major challenge to global agriculture, threatening crop productivity and food security, making the development of effective mitigation strategies essential for sustainable farming. Synthetic bacterial communities (SynCom) improve host plants ability to withstand As stress by several mechanisms. It is well known that polyamines (PAs) strengthen the antioxidant defence system, prevent ethylene formation, preserve cell pH, and shield plant cells from the damaging effects of As, and so forth; nevertheless, it is still unknown how SynCom modify PA metabolism to improve plant resistance to As. Pot experiment was carried out to evaluate how SynCom affects root PA homeostasis, hydrogen peroxide (metabolite associated with PA), genes encoding antioxidant system and expression and activities of PA- associated degrading and synthesizing enzymes in rice subjected to As. SynCom inoculated plants exhibited maximum growth attributes, gene expression of two plasma membrane intrinsic protein, leaf water potential, and chlorophyll contents than non-inoculated plants exposed to As stress. With increased activity of PA catabolic enzymes (copper-containing diamine oxidase, CuAO; polyamine oxidase, PAO) and putrescine synthases (ornithine decarboxylase; arginine decarboxylase, ADC), SynCom inoculated plants resulted in higher putrescine and cadaverine concentrations but lower spermidine and spermine contents. Under As stress, the SynCom inoculated plants resulted in up-regulation of spermine synthase gene, OsSPMS, and down-regulation of PA catabolic enzyme genes (OsCuAO6, OsCuAO8, OsCuAO1 and OsCuAO2) and PA synthase genes (OsADC2 and OsADC1). As stressed plants inoculated with SynCom had higher level of expression in OsPAO1, OsPAO2, OsPAO3 as compared to non-inoculated plants, stimulating reactive oxygen species-associated stress responsiveness signaling through low H2O2 levels by enhancing the genes encoding antioxidant defence system (OsCu/Zn-SOD, OsCAT1 and OsMn-SOD). The results of this study showed that SynCom can alter PA metabolism to improve plants' resistance to heavy metals like As. The inoculation of SynCom emerges as a promising strategy to enhance plant resilience against As toxicity by promoting positive interactions and regulatory stress-responsive pathways. Furthermore, the inoculation of SynCom is a viable approach capable of ameliorating heavy metal stress and improving the productivity of crops in the contaminated soil by fostering positive interactions and stress responsive regulatory mechanisms. (c) 2025 SAAB. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cadmium (Cd) contamination greatly hinders plant productivity. Nanotechnology offers a promising solution for Cd phytotoxicity. The novelty of this study lies in the limited research on the effects of nanoiron (Fe3O4NPs) in regulating Cd toxicity in oilseed crops. This study examined how Fe3O4NPs regulated the Cd-exposure in B. napus. Foliar spray of 10 mg L- 1 Fe3O4NPs was applied to 50 mu M Cd-stressed B. napus seedlings via leaf exposure in hydroponic system. Under Cd stress, Fe3O4NPs decreased the Cd-accumulation (25-37%) due to adsorption followed by more root Cd-immobilization, and increased the plant height (23-31%) and biomass (17-24%). These findings were directly correlated with better photosynthetic activity (chlorophylls, gas exchanges and photosynthetic efficiency), leaf stomata opening and nutrients accumulation (20-29%). Subcellular localization revealed that Fe3O4NPs enhanced the binding capacity of cell wall for Cd to hinder its entry into cell organalles and facilitated vacoular sequestration. Additionally, Fe3O4NPs decreased the oxidative stress (21-33%) and peroxidation of lipids (24-31%) by regulating the genes-associated to superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, glutathione reductase, reduced glutathione, phytochelation, chlorophyll synthesis and Cd-transporters. Fe3O4NPs protected plant roots from Cd-induced cell structural damages and cell death. Among studied parameters, ZD 635 exhibited greater tolerance to Cd stress when compared to ZD 622 cultivar. Findings revealed that Fe3O4NPs effectively mitigate Cd toxicity by improving the photosynthesis, antioxidant defense mechanisms, cellular protection, nutrients accumulation and limiting Cd accumulation. This research offers a benchmark for the practical applicability of Fe3O4NPs to enhance the quality of canola production in Cdcontaminated soils.
Cucumbers, cultivated globally on 3.7 million hectares, face yield losses due to salinity, highlighting the need for effective mitigation strategies for degraded soils. Melatonin (MT) has gained significant interest for its ability to relieve plant stress. To explore the regulatory role of exogenous MT in maintaining redox homeostasis in cucumber seedlings under saline-alkali stress (SA), this study employed the cucumber cultivar 'Xinchun No. 4 '. Simulated saline-alkali conditions were applied, and the effects of exogenous MT on seedling growth, reactive oxygen species (ROS) production, the ascorbate-glutathione (AsA-GSH) cycle, and changes in leaf anatomy were systematically assessed. The findings reveal that exposure to 40 mmol center dot L-1 saline-alkali stress significantly impaired cucumber seedling growth, reduced biomass, and led to excessive accumulation of hydrogen peroxide (H2O2) and superoxide anions (O2 center dot ) in the leaves. This, resulted in increased lipid peroxidation (indicated by elevated malondialdehyde (MDA) levels), whichi further compromised the cell membrane. Application of 10 mu mol center dot L-1 MT effectively reduced ROS levels, lowered MDA content, and mitigated electrolyte leakage. MT also enhanced AsA and GSH levels, improved AsA/DHA and GSH/GSSG ratios, and upregulated key AsA-GSH cycle genes (CsAPX, CsAAO, CsMDAR, CsDHAR, CsGR), leading to a significant increase in enzymatic activity. In addition, MT alleviated stress-induced stomatal closure, thereby restoring normal stomatal function. These findings suggest that MT enhances saline-alkali tolerance by mitigating oxidative damage, promoting antioxidant defenses, and effectively preserving stomatal function. Thus, our study points to a sustainable strategy to improve crop resilience in salinized environments via MT application.
In the arid and semi-arid zones of Northwest China, soil drought and alkaline salt stress often occur simultaneously and affect plant growth at multiple levels. Potato (Solanum tuberosum L.) is a food crop sensitive to drought and alkaline salt stresses and is susceptible to yield loss due to environmental impacts. In recent years, most of the research on abiotic stress response in potato has focused on drought and saline single stresses, and the mechanism of potato response to combined drought-alkaline salt stress and its interactions are still unclear. Therefore, a pot experiment was designed in this study and the potato variety 'Atlantic' was selected as the test material. The effects of drought (25 % PEG-6000), alkaline salt (200 mmol & sdot;L-1 NaHCO3) and combined drought- alkaline salt (25 % PEG-6000 + 200 mmol & sdot;L-1 NaHCO3) stresses on growth traits, micro- and ultrastructure, reactive oxygen species, osmoregulatory substances, and antioxidant defenses of potato were investigated using no stress (CK) as a control, leaf photosynthesis and endogenous plant hormones, and also analyzed the changes in the expression patterns of genes related to plant hormone signal transduction under different stresses. The results showed that drought, alkaline salt, and combined stress affected growth, leaf anatomy, and photosynthesis, and increased the accumulation of osmoregulatory substances in potato. The scavenging activities of antioxidant compounds and antioxidant enzymes were enhanced in potato, and combined stress treatments significantly damaged potato more than single stresses. In 2022, combined stress caused a marked increase in H2O2 (208.7 %) and O2- (455.6 %) content, while in 2023, they increased by 87.5 % and 215.7 %, respectively. SOD, POD, CAT, TPX, APX, GR, GPX and DHAR enzyme activities were increased by 209.13 %, 55.19 %, 152.59 %, 47.13 %, 104.02 %, 347.37 %, 68.45 % and 130.69 % in 2022 compared to CK in the combined stress treatment. In 2023, they increased by 229.81 %, 49.95 %, 160.62 %, 102.16 %, 94.06 %, 505.15 %, 47.00 %, and 121.19 %, respectively. After the stress treatments, the contents of gibberellic acid (GA3) and auxins (IAA) were significantly lower than those in CK, whereas the contents of abscisic acid (ABA), salicylic acid (SA), and brassinosteroids (BRs) increased. Expression of IAA-related genes (AUX1, Aux/IAA, GH3, and SAUR) was up-regulated after stress. ABA-related genes (PYR/PYL, SnRK2, and ABF) were up-regulated after stress, whereas protein phosphatase 2C (PP2C) genes were down-regulated in expression after stress. The GA3 receptor GID1 and the Fbox protein GID2 were up-regulated after stress. Xyloglucosyl transferase TCH4 gene was up-regulated by stress and positively correlated with changes in BRs content. The TGA transcription factor, PR-1 gene, was induced to up-regulate its expression by stress and positively correlated with changes in SA content. Drought, alkaline salt, and combined stress reduced potato tuber yield and quality, which were 54.13 % and 60.14 % lower than CK in combined stress treatments in 2022 and 2023, respectively, which were significantly correlated with changes in physiological and biochemical characteristics and hormone contents of potato plants.