Search Results (168)

High-temperature stress severely restricts plant growth and development by inducing oxidative damage and photosynthetic inhibition. Allene oxide synthase (AOS) is a key enzyme in jasmonic acid (JA) biosynthesis, yet its role in the high-temperature stress response of woody ornamental plants remains largely uncharacterized. In this study, PsAOS3 was isolated and characterized from tree peony (Paeonia suffruticosa Andr.), an economically important ornamental species susceptible to high-temperature stress. PsAOS3 was localized to the plasma membrane and was strongly induced by high-temperature stress. Functional analyses using virus induced gene silencing in tree peony showed that silencing of PsAOS3 accelerated chlorophyll loss, increased reactive oxygen species (ROS) accumulation, impaired photosystem II efficiency and membrane integrity, and reduced antioxidant enzymes and endogenous JA contents under high-temperature stress. Conversely, overexpression of PsAOS3 in tobacco (Nicotiana tabacum L.) alleviated chlorophyll loss, decreased ROS accumulation, improved photosystem II efficiency and membrane integrity, and elevated antioxidant enzymes and endogenous JA contents under high-temperature stress. Collectively, this study reveals a potential role of PsAOS3 in regulating high-temperature responses in tree peony. Full article

Peptides as signaling molecules play an important role in intercellular communication. Exogenous peptides AlaGluAspLeu (AEDL) and AlaGluAsp(OMe)Leu (AED(OMe)L) at a concentration of 10⁻⁷ M stimulate the growth and development of Nicotiana tabacum. A detailed study of Nicotiana tabacum root cells grown in the presence of exogenous peptides AEDL and AED(OMe)L using transmission electron microscopy revealed characteristic differences in the ultrastructure of some cytoplasmic organelles compared to control cells. Importantly, vacuoles and autophagosomes differing in size and content, as well as amyloplasts and proteinoplasts never previously described in the literature, were found in the cells of the outer and inner root cortex. Only lytic vacuoles were detected in the cytoplasm of control cells, whereas in the presence of peptides, predominantly protein-storing vacuoles were found in root cells. In the presence of the exogenous short peptide AEDL, tobacco root cells contained amyloplasts with numerous large starch granules in the stroma, which were not detected in control cells. In the presence of the modified short peptide AED(OMe)L, leukoplasts contained protein bodies. Moreover, in contrast to control cells and cells grown in the presence of the AEDL peptide, a megaphagic (pexophagic) variant of autophagosomes with peroxisomes was detected for the first time in tobacco cells treated with AED(OMe)L. Characteristic types of phagophores were identified, forming numerous small autophagosomes with cytoplasmic regions, multivesicular bodies or concentric membranes, and cytoskeletal elements. Data on the expression of the ATG, TOR, and FREE1 genes confirmed the pattern of the existence of a large number of small autophagosomes. Based on the obtained data, a scheme for the regulation of the formation of root architecture of Nicotiana tabacum in the presence of AEDL and AED(OMe)L was proposed. Full article

Packing density regulates the microenvironment of tobacco (Nicotiana tabacum L.) fermentation and may thereby influence microbial activity and product quality. However, its effects on microbial community assembly and quality formation remain poorly understood. This study aimed to clarify how packing density affects flue-cured tobacco quality by shaping microbial communities, functional potential, and ecological interactions. Here, we investigated the effects of three packing densities (60%, 70%, and 80%) on chemical components, aroma compounds, microbial community structure, functional potential, co-occurrence networks, and assembly mechanisms of flue-cured tobacco (cv. Piaohe No. 2) after 10 days of fermentation. Moderate density (70%) achieved the most balanced chemical profile, with appropriate nicotine retention, potassium/chlorine ratio, and sugar/nicotine balance. T70 also exhibited the highest levels of total esters, total ketones, and β-ionone, key contributors to fruity, floral, and woody aromas. Microbial analysis revealed that T70 supported the highest diversity and was characterized by the enrichment of aroma-related bacterial taxa, including Bacillus and lactic acid bacteria, as well as the fungal genus Pichia. In contrast, T60 favored aerobic nicotine degraders, whereas T80 selected for obligate anaerobes associated with off-odor production. Functional predictions and network analysis showed that T70 upregulated fatty acid and carotenoid biosynthesis pathways and exhibited the highest modularity, indicating a compartmentalized, functionally complementary community. Neutral model fitting revealed increasing stochasticity with density, with T70 displaying a mixed assembly regime. Collectively, our findings show that packing density influences tobacco quality by regulating microbial community composition, functional potential, network interactions, and assembly processes. These results provide a scientific basis for optimizing packing density in tobacco processing. Full article

This study investigates the feasibility of utilizing locally sourced Nicotiana tabacum biomass from Adıyaman, Türkiye, as a cost-effective biosorbent for the removal of copper and chemical oxygen demand (COD) from industrial wastewater originating from the Adıyaman Organized Industrial Zone. Batch adsorption experiments were conducted to systematically investigate the influence of solution pH, contact time, and initial metal concentration on adsorption performance. The untreated wastewater exhibited elevated pollution levels, with mean chemical oxygen demand and copper concentrations of 925 ± 391 mg/L and 2.54 ± 0.97 mg/L, respectively. Four tobacco-derived biosorbents (Çelikhan, Ova, Bulam, and Çağlan) were evaluated under optimized experimental conditions (pH ≈ 8.3, 60 min contact time, and a biosorbent dosage of 2.2 g/L). The Çelikhan biosorbent exhibited the highest copper removal efficiency (approximately 83%), whereas chemical oxygen demand removal ranged between 28% and 34%. The adsorption kinetics were well described by the pseudo-second-order model, with coefficients of determination ranging from 0.987 to 1.000. Isotherm analysis further indicated favorable adsorption behavior, with a maximum Langmuir adsorption capacity of 1.867 mg/g. Fourier transform infrared (FT-IR) spectroscopy confirmed the involvement of hydroxyl, carbonyl, and ester functional groups in metal binding. These findings highlight tobacco biomass as a sustainable and cost-effective biosorbent for industrial wastewater treatment. This study presents the first comprehensive evaluation of locally sourced Adıyaman tobacco biomass as a biosorbent for the removal of copper and organic pollutants from real industrial wastewater, integrating kinetic, isotherm, and FT-IR analyses to elucidate the underlying adsorption mechanisms. Full article

Salinity stress severely inhibits crop growth and reduces yield. Exogenous selenium (Se) enhances plant abiotic stress tolerance, but how different selenium forms exert their impacts and pathways in mitigating salinity remains ambiguous. Under salt stress, this work compared two Se forms, selenate [Se(VI)] and selenite [Se(IV)], regarding their impacts on development, photosynthetic performance, antioxidative system, osmotic regulators, Se buildup, and stress-related gene expression in Nicotiana tabacum L. Both Se species significantly promoted tobacco growth. (1) Under 150 mmol/L NaCl stress, biomass, net photosynthetic rate and antioxidant enzyme activities decreased significantly, while soluble sugar, free proline, Na⁺/K⁺, Na⁺/Ca²⁺, H₂O₂, MDA contents and NtROS2a, NtLEA5 expression increased significantly. (2) Exogenous Se increased biomass, photosynthetic parameters; antioxidant enzyme activities and NtNAC2, NtCDPK12, NtROS2a expression; elevated Se deposition in roots and leaves; and reduced oxidative damage, ion imbalance and NtLEA5 expression in salt-stressed tobacco, suggesting that Se may improve salt tolerance by regulating these physiological processes and stress-related gene expression. (3) Compared with Se(IV), Se(VI) significantly increased root length, chlorophyll content, stomatal conductance, K⁺ content, SOD/CAT activities, leaf and root Se accumulation as well as and NtNAC2, NtCDPK12 expression, while Se(IV) resulted in higher root diameter, free proline content, Na⁺/K⁺ ratio and NtROS2a expression. In conclusion, both sodium selenate and sodium selenite effectively enhanced tobacco salt tolerance. The salt stress alleviation effect of Se(VI) may be associated with upregulating NtNAC2 and NtCDPK12 to improve antioxidant capacity and photosynthesis, thereby potentially maintaining cell membrane integrity and ion balance, while Se(IV) may exert its effect through upregulating NtROS2a to promote root thickening, reactive oxygen species scavenging and osmotic adjustment. At the tested concentrations, selenate was more effective. Full article

Soil salinity severely restricts castor (Ricinus communis L.) seed germination, yet the molecular basis of this trait remains poorly understood. Here, we identified and functionally characterized RcnsLTPC, a nonspecific lipid transfer protein gene strongly induced by salt stress, which encodes a plasma membrane-localized nsLTP1 protein. Promoter analyses indicated that RcnsLTPC is responsive to stress-, hormone-, and light-related signals, supporting its potential role in environmental adaptation. Heterologous expression in Saccharomyces cerevisiae and overexpression in Nicotiana tabacum consistently demonstrated that RcnsLTPC acts as a positive regulator of salt tolerance, improving germination, root development, biomass accumulation, antioxidant capacity, and ion homeostasis under NaCl stress. Notably, ZnO-NPs priming further amplified the protective effects of RcnsLTPC, suggesting a synergistic interaction between nanopriming and gene-mediated stress adaptation. Collectively, these findings establish RcnsLTPC as a key regulator of salt tolerance in castor and provide a conceptual basis for combining nanotechnology with genetic enhancement to improve crop performance on saline soils. Full article

The coexistence of microplastics (MPs) and heavy metals (Cd, Pb) in agricultural soils has become a global environmental and ecological risk. In this study, a pot experiment was conducted to investigate the effects of different concentrations of polyethylene (PE) microplastics and combined Cd/Pb contamination on the growth and development, heavy metal accumulation, and antioxidant system of tobacco (Nicotiana tabacum L. cv. Yunyan 87). The results showed that low-dose PE and low concentrations of heavy metals had minor impacts on tobacco growth and the antioxidant system; in contrast, high-dose PE and elevated heavy metal treatments markedly induced increases in malondialdehyde content (MDA) and enhanced the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). Under co-contaminated conditions, the addition of low-dose PE reduced the translocation capacity of heavy metals, alleviated heavy metal-induced oxidative stress responses, and promoted tobacco growth. Conversely, high-dose PE promoted the translocation of Cd into tobacco plants and increased Cd contents in tobacco leaves, leading to marked decreases in soluble protein and soluble sugar contents, and causing severe reductions in plant height, number of functional leaves, and biomass. Structural equation modeling (SEM) analysis revealed that the direct effect of PE on tobacco growth was not significant; instead, it primarily acted as a regulatory factor, exerting either promotional or inhibitory effects on tobacco growth at different doses. The impact of Cd/Pb on tobacco growth appeared to involve two potential pathways. On the one hand, Cd/Pb induced direct toxicity through their accumulation within tobacco tissues. On the other hand, they exerted indirect regulation primarily by modulating the activities of the tobacco antioxidant system. Full article

Tobacco (Nicotiana tabacum L.) is an industrial crop cultivated worldwide with intensive management systems that include continuous cropping, conventional tillage and high use of agrochemicals. The increasing concerns about environmental and economic sustainability call for innovative practices to maintain yield while managing weeds and enhancing soil fertility. Our research investigated the effect of green manure or cover crops coupled with minimum tillage on Kentucky tobacco production and the level of control of weeds. Six integrated management systems were tested in a four-year trial in Tuscany, Italy: (TS1) conventional farming management as defined above; (TS2) reduction in fertilizers and compost application; (TS3) rotation of tobacco–leguminous green manure and reduction in fertilizers; (TS4) rotation of tobacco–leguminous green manure and compost application without fertilizers; (TS5) rotation of tobacco–mixture of cover crops, minimum tillage before tobacco transplant, reduction in fertilizers; (TS6) as in TS5 but with a compost amendment addition. The different farming practices represented an ecological filter for the weed communities. The combination of conventional tillage, compost application and green manure was sufficient to control weed development. On the other hand, cover crop termination via roller crimper and minimum tillage did not reduce weed pressure, thereby negatively affecting tobacco production. Further studies are needed to improve the effectiveness of mulching and minimal tillage on weed levels not detrimental to tobacco development. It would be advisable to alternate different weed management strategies to prevent community specialization, mitigate negative effects on crops and enhance biodiversity at the farm scale. Full article

Low-temperature stress significantly limits plant growth, development, and productivity, posing a major environmental constraint. The potato (Solanum tuberosum L.) is particularly vulnerable to low temperatures, underscoring the crucial need to enhance cold tolerance in potato breeding efforts for sustainable production. Basic leucine zipper (bZIP) transcription factors serve as central regulators of plant developmental processes and stress responses; however, their functional role in cold tolerance in tetraploid potato remains poorly understood. Here, we report a systematic characterization of the bZIP gene family in tetraploid potato and provide preliminary evidence that StbZIP104 enhances plant cold tolerance. A total of 191 StbZIP genes were identified and classified into 11 subfamilies, exhibiting uneven chromosomal distribution and expansion primarily driven by whole-genome and segmental duplication. Promoter cis-element analysis, together with GO and KEGG enrichment analyses, indicated that StbZIP genes are broadly associated with hormone signaling, stress responses, signal transduction, and environmental adaptation. Expression profiling under low-temperature treatment revealed eight cold-inducible StbZIP genes (log₂FC ≥ 1 and FDR < 0.05), among which StbZIP104 was strongly induced (log₂FC ≥ 2) and showed 5.36-fold higher expression in highly cold-resistant cultivars than in cold-sensitive cultivars. Subcellular localization confirmed that StbZIP104 is a nuclear-localized protein. Functional validation confirmed that overexpressing StbZIP104 notably improved cold tolerance in transgenic Samsun NN tobacco (Nicotiana tabacum cv. Samsun NN). This was supported by heightened superoxide dismutase and peroxidase activities, increased levels of soluble protein and soluble sugars, and decreased malondialdehyde content compared to the wild type under cold stress. This study establishes a basis for the functional characterization of the bZIP gene family in tetraploid potato and serves as a theoretical reference for understanding the mechanisms that govern cold tolerance in this species. Full article

Nicotiana tabacum is a classic model for studying pollination on wet stigma. Reactive oxygen species (ROS) and nitric oxide (NO) production are closely related to stigma fertility and depend on the activity of redox enzymes. This study is devoted to the comparison of two tobacco lines differing in physiological parameters and reproductive success. Samsun is a tobacco variety that is widely used in research due to its low demands; however, the reproductive potential of the variety is quite low. Based on this variety, a new line was obtained, called “Fortune”; the plants are externally similar to the Samsun plants, but are more successful in reproduction. The total production of ROS + NO on the stigmas of the Fortune plants is lower than the Samsun plants, but their ROS production is higher, and the main decrease occurs due to NO. Superoxide dismutase activity differs between the two lines at all stages of stigma development except the fertile stage, while ascorbate peroxidase activity is higher in “Fortune” at all stages. Additional isoforms of ascorbate peroxidase are detected in developing stigmas of the Fortune variety. Presumably due to differences in redox metabolism, Fortune plants produce more seeds, their fruit are larger, and their leaves and flowers are also larger compared to the Samsun plants. In this study, we investigated both redox homeostasis parameters and plant productivity using tobacco as the model plant and suggested that there is a correlation between these groups of parameters, which may be important for breeding highly productive plants. Full article

Phosphorus deficiency in the environment induces phosphate (Pi) starvation responses of plants, in which the phosphate transporter is one of the most critical functional genes in this response mechanism. As a prevalent green manure crop in China, Vicia villosa plays a critical role in sustainable agricultural systems, and the expression of its phosphate transporter gene (VvPHT1) is modulated by soil phosphorus availability, highlighting its key adaptive function in nutrient acquisition and utilization under low-Pi conditions. Functional studies of this gene and its promoter contribute to exploring the molecular mechanisms of the tolerance of green manure crops to low phosphorus stress and to improving phosphorus-efficient V. villosa varieties. In this study, analysis of the VvPHT1 promoter sequence revealed a 1524 bp region containing multiple root-specific cis-regulatory elements, including five NODCON2GM, one NODCON1GM, six OSE2ROOTNODULE, one OSE1ROOTNODULE, and fifteen ROOTMOTIFTAPOX1 motifs. Histochemical GUS staining of transgenic Arabidopsis (Arabidopsis thaliana (L.) Heynh.) showed that the VvPHT1 promoter directed root-specific expression of the GUS reporter gene. A fusion expression vector pCAMBIA1300-VvPHT1--GFP was constructed and transformed into tobacco (Nicotiana tabacum L.) cells for subcellular localization analysis, indicating that the protein encoded by VvPHT1 was localized to the plasma membrane. To quantify its expression, VvPHT1 transcript levels in VvPHT1-overexpressing Arabidopsis (OEPHT1) lines were analyzed by quantitative real-time PCR (qRT-PCR) under different phosphorus supply conditions. The results demonstrated that under low-Pi conditions, the expression of VvPHT1 was significantly upregulated in the OEPHT1 lines compared to those of normal-Pi conditions. Furthermore, under low-Pi treatment, the OEPHT1 lines showed significantly increased fresh weight, primary root length, phosphorus content, and chlorophyll content compared to the wild-type Arabidopsis (WT), while no such differences were observed under normal-Pi conditions. In conclusion, the VvPHT1 promoter exhibits root-specific activity, and the VvPHT1 gene encodes a plasma-membrane-localized phosphate transporter that is strongly induced by phosphorus deficiency. Its overexpression enhances phosphorus uptake and plant growth under low-Pi conditions, suggesting that VvPHT1 likely functions as a high-affinity phosphate transporter involved in the adaptation to phosphorus starvation. Full article

Tobacco (Nicotiana tabacum L.) is an economically important crop in China. The risk of cadmium (Cd) pollution is increasing, making the mitigation of Cd stress critical for the safe production of tobacco. Silicon (Si) has been demonstrated to enhance plant growth under heavy metal stress. To elucidate the physiological and biochemical mechanisms by which Si alleviates Cd stress in tobacco, this study conducted a hydroponic experiment with three replicates using tobacco variety Yunyan 87 and employed one-way analysis of variance (ANOVA) for statistical analysis. The effects of Si on tobacco growth and the antioxidant defense system under Cd stress were investigated. The results showed that Cd stress significantly inhibited tobacco growth, increased Cd accumulation, and induced oxidative damage. Si treatment alleviated Cd stress in tobacco, increased biomass, reduced Cd concentration in different plant organs, and decreased the Cd translocation factor and bioconcentration factor. Meanwhile, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in tobacco roots and leaves were significantly enhanced, while the activities of ascorbate peroxidase (APX) and glutathione reductase (GR) were also elevated. The accumulation of ascorbic acid (AsA) and glutathione (GSH) increased, and malondialdehyde (MDA) concentration decreased. Overall, these results demonstrate that Si mitigates Cd stress in tobacco by limiting Cd accumulation and transport and by coordinately activating both enzymatic and non-enzymatic antioxidant systems. Full article

Synthetic auxins are widely used nowadays as plant growth regulators and necessary components of media for micropropagation. Hence, the search for and development of novel auxin-like compounds is an important goal at the intersection of chemistry and biology. In this study, we have suggested alkylphenols as starting materials for the preparation of halogenated phenoxyacetic acids, which are well-known synthetic auxins, to decrease their possible phytotoxicity. Alkylphenoxyacetic acids were obtained with good yields, and their selective halogenation was studied. N-halogensuccinimides and molecular bromine in dioxane were shown as suitable reagents since they allowed for p-halogenophenoxyacetic acids to be synthesized with high yields. We further investigated the auxin-like activity of several obtained compounds. It was estimated that all of them stimulate tobacco Nicotiana tabacum L. pollen germination at concentrations 10⁻⁶–10⁻⁷ M with the maximum effect up to 157%. For the most efficient compounds, the germination of tobacco (Nicotiana tabacum L.) and corn (Zea mays) seeds was studied, as well as seedling growth. The results demonstrate the efficacy of obtained compounds as synthetic auxins, showing that alkylphenols are prospective starting materials for such compounds. Full article

The influence of three different types of microplastics (PE, PET, and PS) on soil physicochemical properties is the main scope of the present investigation. To this end, a pot experiment has been conducted, incorporating each kind of microplastic (MP) in two different soil samples in equal portions. The soils were typical of Mediterranean areas, moderately contaminated with Pb and Zn. Furthermore, two different plants, Nicotiana tabacum L. (Burley cv.) and Cannabis sativa L. (Fedora cv.), were planted to study the influence of a multi-contaminated soil environment on plant growth, along with their ability to absorb metals in their tissues. The addition of microplastics caused stronger reactions in slightly acidic soil, where the bioavailability of zinc and lead increased by 5–20% compared to alkaline soil rich in CaCO₃. Plant-to-soil indices have been calculated to monitor the plant’s capacity to transfer metals from the soil environment to plant tissues. PE induced the strongest and most consistent responses, increasing Zn and Pb bioavailability and systematically enhancing total concentration factors (TC), bioaccumulation factors (BAF), and translocation factors (TF) by up to 20%, particularly in acid soil, while PET reduced the mobility of metals on the surface while enhancing vertical transport, and PS caused moderate but stable changes. Plant responses were cultivar-dependent. Plant biomass increased by approximately 7–15% in Cannabis sativa L. (cv. Fedora 17), while Nicotiana tabacum L. (cv. Burley) showed greater sensitivity to the presence of microplastics. Even low MP inputs can subtly but persistently modify soil structure, metal dynamics, and soil–plant transfer processes without increasing total metal loads, highlighting the importance of soil chemistry and polymer type in assessing the environmental risk of microplastics for sustainable agroecosystems. Full article

Demand for cosmetics based on green production and the circular economy is growing. The inflorescences and apical leaves of Nicotiana tabacum (tobacco) after blunting, deflowering, or topping are considered pre-harvest waste biomass. Using green and ecofriendly solvents such as natural deep eutectic solvents (NaDESs) offers a sustainable way to make use of this biomass for incorporation in cosmetic formulations. The inflorescence and apical leaves of tobacco var Virginia were therefore dried, powdered, and extracted using a NaDES composed of choline-chloride, urea, and distilled water (NaDES CU). The resulting inflorescence and apical leaves extracts showed high concentrations of phenolic compounds and flavonoids. Both extracts demonstrated significant biological activity and effectively inhibited tyrosinase, the enzyme responsible for melanin regulation and skin aging (IC₅₀ = 50 μg GAE/mL), as well as showing antioxidant capacity (ABTS^•+; SC₅₀ =1.7–7 μg GAE/mL). Ten nanoemulsions containing tobacco leaf- and inflorescence extract-based NaDES CU, formulated using different polysorbates, deionized water and glycerin, were produced. A low-energy emulsification technique at a constant temperature was applied. Considering the droplet size and polydispersity index, only the nanoemulsions containing inflorescence and leaf extracts based on NaDES CU and containing 5% or 10% polysorbate 85 were selected for further stability assessment and characterization. This study highlights the potential of NaDES combined with tobacco waste extracts as a sustainable and non-toxic ingredient in anti-aging and antioxidant cosmetics. Full article