Search Results (147)

Male sterility is an important trait in heterosis utilization and marigold (Tagetes erecta L.) breeding. Currently, most male-sterile lines used in production are derived from natural mutations. ABORTED MICROSPORES (AMS) is an important gene that regulates tapetum and microspore development. Therefore, the effect of AMS on fertility was studied. TeAMS was located in the nucleus and exhibited self-activation activity. TeAMS was highly expressed in the flower buds of T. erecta. The expression of this gene in fertile plants was higher than that in sterile plants, and the expression level gradually increased with the development of flower buds. The expression level of TeAMS was highest in the flower buds with a diameter of 1.2 cm at the floret differentiation stage, while the expression level was extremely low in the flower buds with a diameter of 1.6 cm. The expression trend of TeAMS in sterile plants was opposite to that in fertile plants. At the inflorescence primordium differentiation stage, flower buds with a diameter of 0.2 cm had the highest expression level, and the stem tip had the lowest expression level. In tobacco (Nicotiana tabacum L.), overexpression of the TeAMS gene resulted in shortened floral tubes, increased thousand-seed weight, a reduced flowering period, and decreased flower numbers. The pollen viability of transgenic tobacco was significantly lower than that of the wild type, and the pollen grains were smaller and showed irregular shapes. The pollen wall was dry and shrunk. Some pollen germinal furrows were distorted, and a few were almost invisible. Silencing TeAMS resulted in a longer flowering period in tobacco, reduced thousand-seed weight, and high pollen viability. Pollen morphology in silenced lines showed no significant differences compared to the wild-type and empty vector controls. Only a few pollen grains were smaller, shriveled, and shrunken. Therefore, the TeAMS gene plays an important role in regulating the fertility of marigolds. This study provides a theoretical foundation for breeding marigold male-sterile lines. Full article

Field trials were carried out over two tobacco cropping seasons (2020 and 2021) to assess the effectiveness of soil (PRE-T) and post-transplant (POST-T (OT)) herbicides in a tobacco crop, depending on rainfall and the type of soil. The effectiveness of PRE-T and POST-T (OT) herbicides alternated according to the presence of weeds, treatments, the region, and years. Unpredictable meteorological conditions throughout the two study years likely influenced the control of weeds. An unusually moist May in 2020 with a precipitation of 29 mm in the first WA PRE-T before the emergence of weeds generated the leaching of the PRE-T herbicide from the surface of the soil, which was likely the most probable reason for the reduced effectiveness of PRE-T-applied herbicides (less than 77%) in comparison to the POST-T (OT) application treatment in 2020 in the Prilep region. Conversely, the restricted rainfall after PRE-T and POST-T (OT) application may have caused the unsatisfactory efficacy of both PRE-T and POST-T (OT) herbicide treatments in the Titov Veles region in 2021 (less than 78 and 80%, respectively) in comparison with 2020. Excessive rain immediately after PRE-T and POST-T (OT) application resulted in the injury of tobacco plants in the Prilep region in 2020 and 2021, which was between 8 and 25%, and 7 and 22%, respectively, after seven DAHAs across both treatments. The injuries caused by pendimethalin and metolachlor were more serious. The yields of tobacco after both PRE-T and POST-T treatment in each region typically reflect the overall effectiveness of weed control and the extent of tobacco crop injury. Full article

The cigarette production from Nicotiana tabacum generates significant amounts of waste, with an estimated 68.31 million tons of pre- and post-harvest waste discarded annually. The pre-harvest waste includes the upper parts of the plant, inflorescences, and bracts, which are removed to help the growth of the lower leaves. This study explores the potential of apical leaves from Nicotiana tabacum var. Virginia, discarded during the budding stage (pre-harvest waste). The leaves were extracted using environmentally friendly solvents (green solvents), including distilled water (DW) and two natural deep eutectic solvents (NaDESs), one consisting of simple sugars, fructose, glucose, and sucrose (FGS) and the other consisting of choline chloride and urea (CU). The anti-inflammatory and anti-aging potential of these green extracts was assessed by the inhibition of key enzymes related to skin aging. The xanthine oxidase and lipoxygenase activities were mostly inhibited by CU extracts with IC₅₀ values of 63.50 and 8.0 μg GAE/mL, respectively. The FGS extract exhibited the greatest hyaluronidase inhibition (49.20%), followed by the CU extract (33.20%) and the DW extract (20.80%). Regarding elastase and collagenase inhibition, the CU extract exhibited the highest elastase inhibition, while all extracts inhibited collagenase activity, with values exceeding 65%. Each extract had a distinct chemical profile determined by LC-ESI-QTOF-MS/MS and spectrophotometric methods, with several shared compounds present in different proportions. CU extract is characterized by high concentrations of rutin, nicotiflorin, and azelaic acid, while FGS and DW extracts share major compounds such as quinic acid, fructosyl pyroglutamate, malic acid, and gluconic acid. Ames test and Caenorhabditis elegans assay demonstrated that at the concentrations at which the green tobacco extracts exhibit biological activities, they did not show toxicity. The results support the potential of N. tabacum extracts obtained with NaDESs as antiaging and suggest their promising applications in the cosmetic and cosmeceutical industries. Full article

Dryopteris fragrans (L.) Schott synthesizes volatile sesquiterpenes through the mevalonate pathway (MVA), in which 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) serves as the key rate-limiting enzyme. Although HMGR plays a crucial role in terpenoid biosynthesis, its functional characteristics in D. fragrans and its involvement in stress responses remain unclear. This study identified three HMGR genes (DfHMGR1/2/3) from the transcriptome data of D. fragrans. Bioinformatics analysis revealed that the encoded proteins are localized to the endoplasmic reticulum and share high sequence similarity with fern homologs. Under abiotic stress conditions, DfHMGRs exhibited differential expression patterns, with marked upregulation under salt and drought stress. To validate the functions of these genes, we generated transgenic Nicotiana tabacum L. plants overexpressing DfHMGRs. Compared with wild-type controls, the transgenic lines showed enhanced tolerance to drought and heat stress. Promoter analysis identified functional regulatory regions controlling DfHMGR expression, and co-expression network analysis predicted 21 potential transcriptional regulators. This study validates the function of D. fragrans HMGRs in a heterologous system and provides candidate genes for improving stress resistance in plants. Full article

Plant aquaporin proteins (AQPs) are categorized into seven distinct families, among which, plasma membrane intrinsic proteins (PIPs) play pivotal roles in plant growth and physiological processes. In this study, we identified 11 CpPIP genes in wintersweet (Chimonanthus praecox (L.) Link) based on bioinformatic characterization of gene structural organization, chromosomal localization, and phylogenetic relationships. Subsequent phylogenetic reconstruction resolved two evolutionarily distinct CpPIP subclasses. We focused on the isolation and characterization of CpPIP1;1, which showed the highest expression in floral organs. During flowering, a significant increase was observed in the expression of the CpPIP1;1 gene in response to a gradual reduction in environmental temperature. Moreover, the overexpression of CpPIP1;1 in Arabidopsis thaliana resulted in early flowering and an enhanced tolerance to salt, drought, and cold stress. We subsequently transcriptionally fused the CpPIP1;1 promoter containing MYC and MYB low-temperature response elements to the β-glucuronidase (GUS) reporter gene and introduced this construct into Nicotiana tabacum. GUS activity assays of the transgenic plants revealed that the CpPIP1;1 promoter was effectively expressed in flowers. Furthermore, the promoter transcriptional activity was enhanced in response to salt, drought, cold, gibberellic acid, and methyl jasmonate treatments. Collectively, our findings in this study revealed that CpPIP1;1 plays a key role in the regulation of flowering and stress tolerance in wintersweet plants. Full article

The primary objective of this study was to identify and characterize pathogen defense proteins in the Nicotiana tabacum L. proteome, focusing on their structural, functional, and evolutionary properties, as well as their interactions with pathogen-derived molecules. Specifically, we aimed to comprehensively analyze the proteome to pinpoint potential uncharacterized defense-related protein that has emerging roles in immune responses and antioxidant activity across plants and animals. Through integrated computational approaches, we determined evolutionary relationships, and structural modeling of the selected protein was performed using different modeling software, followed by validation through multiple metrics, including stereochemical checks (Ramachandran plot), MolProbity analysis, and Z-scores. We further investigated the functional binding regions or interaction sites. We performed molecular docking to investigate the molecular interactions between selected proteins and pathogen-associated molecular patterns (PAMPs), specifically β-glucan and peptidoglycan (PGN), to elucidate their defensive mechanisms. Last, normal mode analysis (NMA), molecular dynamics simulation (MDS), and post-simulation analyses were employed to evaluate the stability and mobility of the protein–ligand complexes. Uncharacterized vitellogenin-like protein (VLP: ID A0A1S4CXB2) with the potential defense domain chosen because of its predicted immune-related features, stress response patterns, and unknown pathogen role at new immunity functions. Phylogenetic analysis revealed significant sequence homology with VLPs from other members of the Solanaceae family. Structural modeling showed a high-quality model, with docking studies indicating a stronger affinity for PGN (−10.16 kcal/mol) and β-glucan (−7.19 kcal/mol), highlighting its potential involvement in pathogen defense. NMA, MDS, and post-simulation analyses revealed that PGN exhibits more substantial binding stability and more extensive interactions with VLP than β-glucan. Our findings confirmed that VLPs in N. tabacum may function as pattern recognition receptors (PRRs), capable of recognizing and responding to pathogens by activating immune signaling pathways. Future experimental validation of these interactions could further elucidate the role of VLPs in plant defense and their potential application in biotechnological approaches for sustainable agriculture. Full article

The MYB family plays a vital role in regulating plant stress resistance. However, the MYB protein in blue honeysuckle remains largely unexplored. In this study, the LcMYB90 gene from blue honeysuckle ‘Lanjingling’ was stably transformed into tobacco and transiently transformed into blue honeysuckle to characterize its function. Subcellular localization analysis revealed that the LcMYB90 protein is localized in the nucleus. Transgenic plants overexpressing LcMYB90 exhibited enhanced growth performance and higher survival rates under drought and salt stress conditions. These plants also showed increased levels of proline and chlorophyll, along with elevated activities of catalase, peroxidase, and superoxide dismutase. Conversely, malondialdehyde content and relative conductivity were lower, indicating that LcMYB90 enhances tolerance to drought and salt stress. Under salt treatment, genes induced by osmotic stress, such as NHX1 (Na⁺/H⁺ antiporters 1) and SOS1 (salt overly sensitive 1), as well as antioxidant defense system genes like SOD (superoxide dismutase) and CAT1 (catalase 1), were more highly induced in overexpression lines compared to the wild type, supporting the hypothesis that LcMYB90 promotes salt tolerance by enhancing osmotic stress resistance and antioxidant capacity. Simultaneously, the transcription levels of genes involved in the abscisic acid pathway, including NCED1/2 (9-cis-epoxycarotenoid dioxygenase 1/2, PYL4/8 (pyrabactin resistance-Like 4/8), and CBL1 (Calcineurin B-like protein 1), were increased under drought stress conditions in the overexpression lines. These results suggest that LcMYB90 maintains cellular homeostasis by promoting the expression of stress-related genes and regulating osmotic and oxidative substances, thereby improving tolerance to drought and salt stress. Full article

Drought, exacerbated by global warming, poses a significant threat to crop growth and productivity. This study identified a strain of Trichoderma harzianum from the rhizosphere of healthy Nicotiana tabacum L. plants and evaluated its role in enhancing drought tolerance. The isolated strain effectively colonized plant roots and promoted the growth of N. tabacum L. To investigate its potential, T. harzianum was inoculated into plants under varying drought conditions, and its impact on growth, physiological responses, and drought resilience was assessed. Comprehensive analyses of agronomic traits, physiological parameters, enzyme activities, photosynthetic performance, osmoprotectant levels, and membrane lipid peroxidation revealed that T. harzianum inoculation (light drought with T. harzianum, moderate drought with T. harzianum, and severe drought with T. harzianum treatments) systematically improved plant development and drought resistance. These findings provide valuable insights and lay a foundation for developing innovative biofertilizers to enhance crop drought tolerance and sustainability. Full article

A field experiment was conducted in 2018 at Marciano della Chiana (Arezzo, AR, Central Italy) with the main aim of investigating the effect of soil amendment with organic fraction municipal solid waste (OFMSW) compost and legume green manuring (Vicia villosa Roth, cv. villana) on a tobacco crop (dark fire-cured Kentucky type, cv. Foiano) grown under both full (100% of ET_c) and deficit (70% of crop evapotranspiration, ET_c) irrigation. The treatments are hereafter reported as GM (vetch green manuring) and NGM (no vetch green manuring), FI (full irrigation) and DI (deficit irrigation), and C (compost soil amendment) and NC (no compost soil amendment). The following parameters were calculated: (i) yield of the cured product (CLY, Mg ha⁻¹) at a standard moisture content of 19%; (ii) irrigation water use efficiency (IWUE, kg of cured product m⁻³ seasonal irrigation volume), nitrogen (N) agronomic efficiency (NAE, kg of cured product kg⁻¹ mineral N by synthetic fertilizers). Dry biomass accumulated in the stem and leaves (Mg ha⁻¹) was also measured at 25, 57, 74, and 92 days after transplanting (DAT). The N recovery from the different plant parts (kg ha⁻¹) was determined at 57 and 74 DAT. The C/N ratio, NO₃-N (kg ha⁻¹), the soil organic matter (SOM, %), and the soil contents of P₂O₅ and K₂O (mg kg⁻¹) were also analytically determined at 43, 74, and 116 DAT. Water retention measurements were carried out on soil samples at 116 DAT at 0–0.3 and 0.3–0.6 soil depths. Overall, there was a negative effect of both compost amendment and green manuring on yield. Green manuring and compost soil amendment improved soil chemical characteristics (i.e., SOM and C/N), as well as the plant N recovery, the IWUE, and the NAE. They increased the water retention capacity of the soil when the tobacco crop was deficit-irrigated and appeared to be promising practices to support the deficit irrigation strategy, contributing to reaching good agronomic results, although under the conditions of water shortage, and showing synergistic action in those conditions. Full article

Endophytic fungi possess a unique ability to produce abundant secondary metabolites, which play an active role in the growth and development of host plants. In this study, chemical investigations on the endophytic fungus Aspergillus japonicus TE-739D derived from the cultivated tobacco (Nicotiana tabacum L.) afforded two new polyketide derivatives, namely japoniones A (1) and B (2), as well as four previously reported compounds 3–6. Their chemical structures were elucidated by detailed spectroscopic analyses and quantum chemical calculations. In the herbicidal assays on the germination and radicle growth of Amaranthus retroflexus L. and Eleusine indica seeds, compound 1 was found to inhibit the germ and radicle elongation. Notably, compound 2 showed potent herbicidal activity against A. retroflexus L. germ elongation, with an IC₅₀ value of 43.6 μg/mL, even higher than the positive control glyphosate (IC₅₀ = 76.0 μg/mL). Moreover, compound 4 demonstrated strong antibacterial effects against the pathogens Bacillus cereus and Bacillus subtilis, with a comparable MIC value of 16 μg/mL to the positive control chloramphenicol. These findings indicate that the endophytic fungus A. japonicus TE-739D holds significant metabolic potential to produce bioactive secondary metabolites, which are beneficial, providing survival value to the host plants. Full article

The epigenetic variation in protoplast regeneration is a topic that has attracted interest recently. To elucidate the role of DNA methylation in the regeneration of protoplasts from the ponkan (Citrus reticulata), this study employs the methylation-sensitive amplification polymorphism (MSAP) molecular marker technique to analyze changes in DNA methylation levels and patterns during the isolation and culture of protoplasts from ponkan and tobacco. Additionally, differential DNA methylation fragments are cloned, sequenced, and subjected to bioinformatics analysis. The results reveal that, for non-regenerable ponkan mesophyll protoplasts, DNA methylation levels increase by 3.98% after isolation and then show a trend of initial decrease followed by an increase during culture. In contrast, for regenerable ponkan callus protoplasts and tobacco mesophyll protoplasts, DNA methylation levels decrease by 1.75% and 2.33%, respectively, after isolation. During culture, the DNA methylation levels of ponkan callus protoplasts first increase and then decrease, while those of tobacco mesophyll protoplasts show an opposite trend of initial decrease followed by an increase. Regarding DNA methylation patterns, ponkan mesophyll protoplasts exhibit primarily hypermethylation changes accompanied by a small amount of gene demethylation, whereas ponkan callus protoplasts are dominated by demethylation changes with some genes undergoing hypermethylation. The methylation exhibits dynamic changes in protoplast isolation regeneration. By recovering, cloning, sequencing, and performing BLASTn alignment analysis on specific methylation modification sites in the ponkan, 18 DNA sequences with high homology are identified which are found to be involved in various biological functions, thereby establishing a foundational basis for genetic editing in protoplasts. Full article

The primary constituents of the essential oil derived from Santalum album L. are (Z)-α-santalol, (Z)-β-santalol, (Z)-α-exo-bergamotol, and (Z)-epi-β- santalol. SaCYP736A167 plays a pivotal role in the biosynthesis of these sesquiterpene alcohols within S. album, but the mechanisms governing the expression of the SaCYP736A167 gene is far from being deciphered. In this research, a promoter sequence of the SaCYP736A167 gene, spanning 2808 base pairs, was isolated from S. album. A bioinformatics analysis of the 2384-bp SaCYP736A167 promoter (PSaCYP736A167) showed that abundant stress-inducible cis-acting elements were distributed in different regions of PSaCYP736A167. The histochemical β-glucuronidase (GUS) staining of T1 transgenic Nicotiana tabacum plants harboring PSaCYP736A167 demonstrated that the predominant GUS activity was exhibited in the parenchyma cells of the stem cortex and phloem, suggesting that PSaCYP736A167 is a tissue-specific expression promoter. GUS fluorometric assays of transiently transgenic N. benthamiana leaves revealed that seven distinct segments of PSaCYP736A167 exhibited notably varied levels of GUS activity. A 936-base pair sequence upstream of the transcription initiation codon ATG constitutes the core promoter section of PSaCYP736A167. Our findings shed light on the regulatory mechanisms controlling the transcription of the SaCYP736A167 gene, potentially serving as a novel tissue-specific promoter for applications in transgenic plant biotechnology. Full article

Soluble inorganic pyrophosphatase (s-PPase), a pyrophosphate hydrolase, is crucial for various physiological processes including plant growth and development, metabolic functions, and responses to abiotic stresses. However, research on s-PPase in woody plants is limited. To investigate the potential role of soluble inorganic pyrophosphatase in Eucommia ulmoides Oliver (E. ulmoides) in drought stress, the E. ulmoides soluble inorganic pyrophosphatase 5 (EuSIP5) cDNA sequence was amplified via RT-PCR. A bioinformatic analysis suggested that EuSIP5 may be an unstable amphipathic protein predominantly localized in the cytoplasm. In E. ulmoides, the highest expression of the EuSIP5 gene was detected in the leaves and pericarp of male plants from April to October, and in the leaves in July and September. Under drought conditions, the expression of EuSIP5 in E. ulmoides leaves was significantly greater than that in the control. An overexpression vector containing EuSIP5 was constructed and introduced into Nicotiana tabacum L. cv. Xanthi (N. tabacum L.). Compared with that in wild-type (WT) plants, wilting in N. tabacum L. EuSIP5-overexpressing (OE) plants was delayed by 4 days under drought stress. Additionally, the expression levels of the drought-related genes DET2, CYP85A1, P5CS, ERF1, F-box, and NCED1 were elevated in the leaves of transgenic N. tabacum L. Moreover, the activities of the protective enzymes peroxidase, superoxide dismutase, and catalase were significantly greater, whereas the malondialdehyde content was lower in the transgenic plants than in the WT plants. These findings suggest that the introduction of the EuSIP5 gene into N. tabacum L. enhances drought-related gene expression, increases antioxidant capacity, and reduces oxidative stress damage, thereby improving drought resistance. Full article

Leymus chinensis, a halophytic perennial grass belonging to the Poaceae family, thrives in saline-alkali grasslands and harbors a rich repository of resistance-related genetic resources. This study focused on deciphering the stress-responsive mechanisms of L. chinensis by conducting transcriptomic sequencing under NaHCO₃ stress, which resulted in the annotation of a segment corresponding to the 51WRKY gene. The alkali-induced gene LcWRKY40 (QIG37591) was identified by phylogenetic analysis. Real-time quantitative PCR analysis was performed on L. chinensis plants subjected to PEG6000 and alkaline salt (NaHCO₃) stress, and the results indicated that the LcWRKY40 gene was upregulated in both the leaves and roots. The localization of the LcWRKY40 protein was confirmed by the use of green fluorescent protein (GFP) fusion technology in transformed rice protoplast cells. The GAL4-driven transformation of the LcWRKY40 gene in INVScI yeast cells, which exhibited enhanced tolerance upon overexpression of the LcWRKY40 gene under mannitol and alkaline salt (NaHCO₃) stress conditions. Under drought stress using mannitol, the fresh weight of Nicotiana tabacum overexpressing the LcWRKY40 gene was significantly higher than that of wild-type(WT) tobacco. Through drought and salt alkali stress, we found that overexpressed tobacco at different stages always outperformed the wild type in terms of fresh weight, SOD, MDA, and Fv/Fm. This study provides preliminary insights into the involvement of the LcWRKY40 gene in responding to drought and alkaline salt stresses, highlighting its role in enhancing plant resistance to drought and saline-alkaline conditions. These findings lay the foundation for future molecular breeding strategies aimed at improving grass resistance from different aspects. Full article