Plants, Volume 12, Issue 22 (November-2 2023) – 132 articles

Heat shock transcription factors are key players in a number of transcriptional regulatory pathways that function during plant growth and development. However, their mode of action in Rhododendron simsii is still unclear. In this study, 22 RsHsf genes were identified from genomic data of R. simsii. The 22 genes were randomly distributed on 12 chromosomes, and were divided into three major groups according to their phylogenetic relationships. The structures and conserved motifs were predicted for the 22 genes. Analysis of cis-acting elements revealed stress-responsive and phytohormone-responsive elements in the gene promoter regions, but the types and number varied among the different groups of genes. Transcriptional profile analyses revealed that RsHsfs were expressed in a tissue-specific manner, with particularly high transcript levels in the roots. The transcriptional profiles under abiotic stress were detected by qRT-PCR, and the results further validated the critical function of RsHsfs. This study provides basic information about RsHsf family in R. simsii, and paves the way for further research to clarify their precise roles and to breed new stress-tolerant varieties. Full article

Chestnut (Castanea mollissima Blume) is an important economic tree owing to its tasty fruit and adaptability to environmental stresses, especially drought. Currently, there is limited information about non-specific lipid transfer protein (nsLTP) genes that respond to abiotic stress in chestnuts. Here, a chestnut nsLTP, named CmnsLTP6.9, was identified and analyzed. The results showed that the CmnsLTP6.9 protein localized in the extracellular matrix had two splicing variants (CmnsLTP6.9L and CmnsLTP6.9S). Compared with CmnsLTP6.9L, CmnsLTP6.9S had an 87 bp deletion in the 5′-terminal. Overexpression of CmnsLTP6.9L in Arabidopsis enhanced tolerance to osmotic and drought stress. Upon exposure to osmotic and drought treatment, CmnsLTP6.9L could increase reactive oxygen species (ROS)-scavenging enzyme activity, alleviating ROS damage. However, CmnsLTP6.9S-overexpressing lines showed no significant differences in phenotype, ROS content, and related enzyme activities compared with the wild type (WT) under osmotic and drought treatment. Moreover, lipid metabolism analysis confirmed that, unlike CmnsLTP6.9S, CmnsLTP6.9L mainly altered and upregulated many fatty acyls and glycerophospholipids, which implied that CmnsLTP6.9L and CmnsLTP6.9S played different roles in lipid transference in the chestnut. Taken together, we analyzed the functions of CmnsLTP6.9L and CmnsLTP6.9S, and demonstrated that CmnsLTP6.9L enhanced drought and osmotic stress tolerance through ROS scavenging and lipid metabolism. Full article

The Altai Mountains are an important center of biodiversity and are a major habitat for threatened and endemic species in Asia. Moreover, the Altai Mountains are a valuable site for the study of the evolution of central Asian vegetation. The Xinjiang Altai subrange represents the largest part of the southern Altai Mountains and has many unique plant communities. After conducting a thorough literature review and field investigation, we utilized the Chinese vegetation categorization system to identify the dominant plant communities in the Xinjiang Altai subrange and report their composition and distribution characteristics. Our results show that (1) the natural plant communities present in the Xinjiang Altai subrange can be divided into eight vegetation types, eighteen vegetation subtypes, and 50 communities. Among these, two communities—Form. Calligonum rubicundum and Form. Seriphidium borotalense-Festuca valesiaca—are present only in the Xinjiang Altai subrange. (2) The Xinjiang Altai subrange is located at the junction of three major biomes containing unique vegetation types (coniferous forest, temperate broadleaf forest, and desert). Thus, the Xinjiang Altai subrange is distinct in its staggered transition from mountainous boreal taiga to temperate desert. This research provides textual data to contextualize the cultural heritage of the Xinjiang Altai subrange and also provides a scientific basis for the protection and sustainable management of natural resources found in the Xinjiang Altai. Full article

Different drying techniques may alter the chemical composition of plant extracts and consequently affect their bioactivity potential. The current study was designed to reveal the effect of four different drying methods on the phytochemical composition and antioxidant activity of hydrodistilled essential oil (HD-EO) and methanolic (APM) extract obtained from the aerial part of Anthemis palestina from Jordan. Aerial parts of A. palestina in their fresh (FR) form and after drying in shade (ShD), sun (SD), oven at 40 °C (O40D) and 60 °C (O60D), in addition to microwave (MWD), were used to extract their essential oils by hydrodistillation and to prepare the different methanolic extracts (APM). GC/MS analysis of the different HD-EOs revealed qualitative and quantitative differences among the different samples. While FR, O40D, O60D, and MWD EO samples contained mainly sesquiterpene hydrocarbons (35.43%, 29.04%, 53.69%, and 59.38%, respectively), ShD sample was rich in oxygenated monoterpenes (33.57%), and SD-EO contained mainly oxygenated sesquiterpenes (40.36%). Principal component analysis (PCA) and Cluster analysis (CA) grouped the different drying methods based on their impact on the concentration of chemical constituents. SD-EO demonstrated high DPPH and ABTS antioxidant activity (1.31 ± 0.03) × 10⁻²; (1.66 ± 0.06) × 10⁻² μg/mL, respectively). Furthermore, A. paleistina methanolic extracts (APM) obtained after subjecting the plant to different drying methods showed interesting patterns in terms of their TPC, TFC, antioxidant activity, and phytochemical profiling. Of all extracts, SD-APM extract had the highest TPC (105.37 ± 0.19 mg GA/g DE), highest TFC (305.16 ± 3.93 mg Q/g DE) and demonstrated the highest DPPH and ABTS scavenging activities ((4.42 ± 0.02) × 10⁻²; (3.87 ± 0.02) × 10⁻² mg/mL, respectively); all were supported by correlation studies. LC-MS/MS analysis of the different extracts revealed the richness of the SD-APM extract in phenolic acids and flavonoids. Full article

With global climate change, changes in vegetation phenology have become increasingly evident. Horqin Sandy Land is located near the eastern part of the West Liaohe River. It is the largest sandy land in China and its ecological environment is fragile. Investigating the changes in vegetation phenology in these sandy areas and determining the relationship between vegetation phenology and meteorological factors are of great importance for predicting the impacts of future climate change and understanding the response mechanisms of ecosystems. In this study, we used the time series of the Normalized Difference Vegetation Index (NDVI) from 2000 to 2021 and extracted the vegetation phenology in the Horqin Sandy Land using high-order curve fitting methods, including the start date of the growing season (SOS), the end date of the growing season (EOS), and the length of the growing season (LOS). We analyzed their temporal variation and used partial correlation analysis to determine their relationship with meteorological factors (temperature and precipitation). In addition, we compared the phenology and microclimate of forest and grassland within the study area. In the Horqin Sandy Land, the vegetation SOS was concentrated between the 115th and 150th day, the EOS was concentrated between the 260th and 305th day, and the LOS ranged from 125 to 190 days. Over the past 22 years, the SOS, EOS, and LOS of vegetation in the Horqin Sandy Land showed trends of delay, shift, and extension, with rates of change of 0.82 d/10a, 5.82 d/10a, and 5.00 d/10a, respectively. The start date of the growing season in the Horqin Sandy Land was mainly influenced by precipitation in April of the current year, while the end date was mainly influenced by precipitation in August of the current year. Overall, the SOS in the forested areas of the Horqin Sandy Land was slightly later than in the grasslands, but the EOS in the forested areas was significantly later than in the grasslands, resulting in a longer LOS in the forests. In addition, annual precipitation and the rate of precipitation increase were higher in the forested areas than in the grasslands, but soil temperature was higher in the grasslands than in the forests. Vegetation phenology in the Horqin Sandy Land has undergone significant changes, mainly manifested in the delayed end date of the growing season, the extended length of the growing season, and the differences between forest and grassland. This indicates that climate change has indeed affected phenological changes and provides a theoretical basis for subsequent ecological restoration and desertification prevention efforts in the region. Full article

The EPIDERMAL PATTERNING FACTOR (EPF) plays a crucial role in plant response to abiotic stress. While the EPF has been extensively studied in model plants such as Arabidopsis thaliana, there is a lack of research on identifying EPF genes in the whole sorghum genome and its response to drought stress. In this study, we employed bioinformatics tools to identify 12 EPF members in sorghum. Phylogenetic tree analysis revealed that SbEPFs can be categorized into four branches. Further examination of the gene structure and protein conservation motifs of EPF family members demonstrated the high conservation of the SbEPF sequence. The promoter region of SbEPFs was found to encompass cis-elements responsive to stress and plant hormones. Moreover, real-time fluorescence quantitative results indicated that the SbEPFs have a tissue-specific expression. Under drought stress treatment, most SbEPF members were significantly up-regulated, indicating their potential role in drought response. Our research findings establish a foundation for investigating the function of SbEPFs and offer candidate genes for stress-resistant breeding and enhanced production in sorghum. Full article

Sulfur deficiency severely limits soybean growth, inhibiting the rhizobia nitrogenase and soybean protein synthesis. This study assessed the impact of sulfur fertilization and rhizobia inoculation on soybean growth and nitrogen fixation through bacterial culture and hydroponic experiments. We selected three rhizobia strains for bacterial cultures and used six sulfur levels. The test demonstrated severe inhibition of Rhizobium USDA110 growth without sulfur. In hydroponic experiment, we employed five sulfur levels with USDA110 as the inoculum strain. Soybean growth, nitrogen fixation, yield, and root morphology-related parameters, and root nodule growth, were significantly inhibited without sulfur. Following Rhizobium inoculation, low sulfur concentrations (0.15–0.60 mM) stimulated early-stage (V9) root growth and increased shoot nitrogen accumulation, but inhibited root growth at R5 stage. Furthermore, Rhizobium inoculation notably enhanced soybean growth, nitrogen fixation, and yield, especially within the recommended low sulfur concentration range (0.15–0.30 mM). The maximum nodule nitrogenase activity at R5 stage and highest yield was recorded at a 0.3 mM sulfur concentration with Rhizobium inoculation, which was 9.51–1222.07% higher than other treatments. These findings highlight that low sulfur concentration and rhizobia inoculation enhance soybean growth, nitrogen fixation, and yield but reduce soybean root efficacy, increasing reliance on root nodules. Full article

Crop perennialization has garnered global attention recently due to its role in sustainable agriculture. However, there is still a lack of detailed information regarding perennial rice’s regenerative characteristics and physiological mechanisms in crop ratooning systems with different rice stubble heights. In addition, the response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice remains poorly documented. Here, we explored the regenerative characteristics and physiological mechanisms of an annual hybrid rice, AR2640, and a perennial rice, PR25, subjected to different stubble heights (5, 10, and 15 cm). The response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice were also investigated. The results show that PR25 overwintered successfully and produced the highest yield, especially in the second ratoon season, mainly due to its extended growth duration, higher number of mother stems, tillers at the basal nodes, higher number of effective panicles, and heavier grain weight when subjected to lower stubble heights. Further analysis revealed that PR25 exhibited a higher regeneration rate from the lower-position nodes in the stem with lower stubble heights. this was primarily due to the higher contents of phytohormones, especially auxin (IAA) and gibberellin (GA₃) at an early stage and abscisic acid (ABA) at a later stage after harvesting of the main crop. Our findings reveal how ratoon rice enhances performance based on different stubble heights, which provides valuable insights and serves as crucial references for delving deeper into cultivating high-yielding perennial rice. Full article

Propolis, a natural resin created by bees, has garnered significant attention from both the scientific community and industry due to an impressive range of bioactivities. Nonetheless, the intrinsic variability in its chemical composition and bioactive profiles has been hindering propolis’ full potential use. We previously showed that ethanol extracts (EEs) of a Portuguese propolis sample (Gerês) collected over four consecutive years displayed similar chemical and biological profiles, a constancy never documented before. However, the characteristics of the unprocessed samples of Gerês propolis were never described. Hence, the central objective of this study is to assess the quality parameters of unprocessed propolis samples collected from Gerês (G), over a four-year period (2019–2022), alongside the analysis of the chemical composition and bioactivities of the EEs prepared with the same raw samples. The ash, wax, balsam and water contents of the unprocessed samples—G19 to G22—showed minor fluctuations, likely attributed to uncontrollable natural events impacting the propolis source and collection process. On the other hand, the antimicrobial and antioxidant activities of all the four ethanol extracts (G19.EE–G22.EE) consistently align with prior studies. Furthermore, the Gerês propolis extracts showed remarkable uniformity in chemical composition parameters too, particularly concerning total polyphenol, flavonoid and ortho-diphenol contents. In summary, our research reinforces the beneficial properties of propolis and show that extracts’ bioactivities remain within the reference ranges for Gerês propolis, despite minor differences in unprocessed samples, suggesting a consistent action over time. Thus, this work could be instrumental towards the establishment of standard parameters for propolis applications, offering valuable insights to this field of propolis research. Full article

Hedera helix L. contains phytochemicals with good biological properties which are beneficial to human health and can be used to protect plants against different diseases. The aim of this research was to find the most suitable extraction method and the most favorable parameters for the extraction of different bioactive compounds from ivy leaves. Different extraction methods, namely microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and conventional heating extraction (CHE), were used. The most suitable method for the extraction of saponins is MAE with an extraction efficiency of 58%, while for carbohydrates and polyphenols, the best results were achieved via UAE with an extraction efficiency of 61.7% and 63.5%, respectively. The antioxidant activity (AA) of the extracts was also determined. The highest AA was obtained via UAE (368.98 ± 9.01 µmol TR/gDM). Better results were achieved at 50 °C for 10 min of extraction, using 80% ethanol in water as solvent. In order to evaluate their in vitro cytotoxicity, the extracts richest in bioactive compounds were tested on NCTC fibroblasts. Their influence on the DNA content of RAW 264.7 murine macrophages was also tested. Until 200 µg/mL, the extracts obtained via UAE and MAE were cytocompatible with NCTC fibroblasts at 48 h of treatment. Summarizing the above, both MAE and UAE can be employed as green and efficient methods for producing extracts rich in bioactive compounds, exhibiting strong antioxidant properties and good noncytotoxic activity. Full article

This study aimed to investigate the combined effect of high temperatures 10 °C above the optimum and water withholding during microgametogenesis on vegetative processes and determine the response of winter barley genotypes with contrasting tolerance. For this purpose, two barley varieties were analyzed to compare the effect of heat and drought co-stress on their phenology, morpho-anatomy, physiological and biochemical responses and yield constituents. Genotypic variation was observed in response to heat and drought co-stress, which was attributed to differences in anatomy, ultrastructure and physiological and metabolic processes. The co-stress-induced reduction in relative water content, total soluble protein and carbohydrate contents, photosynthetic pigment contents and photosynthetic efficiency of the sensitive Spinner variety was significantly greater than the tolerant Lambada genotype. Based on these observations, it has been concluded that the heat-and-drought stress-tolerance of the Lambada variety is related to the lower initial chlorophyll content of the leaves, the relative resistance of photosynthetic pigments towards stress-triggered degradation, retained photosynthetic parameters and better-preserved leaf ultrastructure. Understanding the key factors underlying heat and drought co-stress tolerance in barley may enable breeders to create barley varieties with improved yield stability under a changing climate. Full article

Soil salinity is a well-known abiotic factor affecting the germination and seedling growth of various plant species. Therefore, we evaluated the effects of different chloride salts (NaCl, KCl and MgCl₂) and sulfate salts (Na₂SO₄, K₂SO₄ and MgSO₄) on the seed germination and early seedling growth of two important ethnomedicinal shrubs of North Africa and the Mediterranean basin (Ballota hirsuta and Myrtus communis). Seeds of these species were subjected to five salinity levels (0–100 mM) and incubated at 20 °C under a light regime (12 h photoperiod). Both species demonstrated their highest germination percentage under control conditions (i.e., without salinity). However, as salinity levels increased, the germination percentages for both species decreased, regardless of the type of salt used. Cations appeared to be more determinative than the anions in regulating the seed germination of both species. M. communis seeds displayed greater sensitivity to sodium (Na⁺) salts, especially when accompanied with chloride (Cl⁻) anions. At the higher salt concentrations (75 and 100 mM), Na⁺ salts had a more pronounced inhibitory effect on M. communis seedling growth compared to potassium (K⁺) and magnesium (Mg²⁺) salts. Conversely, Mg²⁺ salts were more detrimental to seedling growth in B. hirsuta. Based on our results, it can be concluded that both of these species are able to tolerate a moderate level of salinity. Overall, B. hirsuta may be a promising choice for rehabilitating the soils dominated by chloride salts, while M. communis could be utilized for restoring sulfate-dominated soils. Full article

Pymetrozine is used on potato (S. tuberosum) and Chrysanthemum morifolium (C. morifolium) to obtain greater yield and quality. However, pesticide use carries the potential for residues to remain and be detected on harvested crops. Therefore, the aim of this study was to estimate pesticide residues in S. tuberosum and C. morifolium products that are commercially available for human consumption and to assess the associated dietary risks. For this study, a total of 340 samples (200 S. tuberosum samples and 140 C. morifolium samples) were collected randomly from supermarkets and farmer’s markets. Residues of pymetrozine in S. tuberosum and C. morifolium were detected by using an established and validated QuECHERS-HPLC-MS / MS method, while a dietary risk assessment of pymetrozine in S. tuberosum and C. morifolium was performed using these data. The detection rates of pymetrozine in S. tuberosum and C. morifolium samples were 92.31% and 98.17%, respectively, with residues not more than 0.036 and 0.024 mg/kg, respectively. Based on these results, the dietary risk assessment indicated that the intake of pymetrozine residues in S. tuberosum and C. morifolium does not pose a health risk. This work improved our understanding of the potential exposure risk of pymetrozine in S. tuberosum and C. morifolium. Full article

The present work was conducted to evaluate the volatile profile of Ecuadorian Forastero, CCN-51, ETT103 and LR14 cocoa beans during traditional fermentation in laurel wood boxes followed by a sun-drying process. Fifty-six volatiles were identified with HS-SPME-GC–MS. Aldehydes, alcohols and ketones were the compounds that mainly characterized the fresh cocoa. The main compounds formed during the anaerobic fermentation step were esters and acids, while in the aerobic fermentation step, an increase in ester-, aldehyde- and acid-type compounds was observed. Finally, after the drying step, a notable increase in the acid (i.e., acetic acid) content was the predominant trend. According to the genotypes, ETT103 presented high contents of terpenes, alcohols, aldehydes and ketones and low contents of unfavorable acid compounds. The CCN-51 and LR14 (Trinitarian) varieties stood out for their highest amounts in acids (i.e., acetic acid) at the end of primary processing. Finally, the Forastero cocoa beans were highlighted for their low acid and high trimethylpyrazine contents. According to the chemometric and Venn diagram analyses, ETT-103 was an interestingly high-aromatic-quality variety for cocoa gourmet preparations. The results also showed the need for good control of the processing steps (using prefermentative treatments, starter cultures, etc.) on Ecuadorian genotypes of Trinitarian origin. Full article

The study of reproductive morphology and trait evolution provides a vital insight to understand the evolutionary history of plants. The conifer family Podocarpaceae has a remarkable diversity of seed cones, with distinct morphology among the genera and with conifers in general. However, we lack a good understanding of the seed cone morpho-anatomy and trait evolution of Podocarpaceae. We investigated detailed seed cone morpho-anatomy using staining and sectioning techniques to clarify the anatomical, morphological diversity and evolution of functional traits. The presence of a fleshy receptaculum is a characteristic feature of both clades. However, species of Retrophyllum, Afrocarpus and some species of Nageia and Podocarpus form a fleshy sarcotesta-like seed coat, lacking a fleshy receptaculum. The ancestral state reconstructions show a shift between and sometimes within the genus. Although both clades demonstrate fleshiness as an ancestral trait, the shift in fleshy structures provides evidence for complex multiple evolutions of fleshy morphologies. These seed cone traits (e.g., fleshiness and size), along with the broad, flattened and well-adapted (leaf dimorphism) foliage in both clades, are largely congruent with efficient light harvesting and bird dispersal. These traits make these two clades well adapted to their environment, when growing in communities including tall and broad-leaved angiosperms (closed-canopy angiosperm forests), compared to other podocarps, making them more successful in achieving a wider distribution and species richness. Full article

The presence of high levels of secondary metabolites in medicinal plants can significantly influence the progress of drug development. Here, we aimed to maximize phenolic extraction from Adenanthera pavonina L. stem bark using various solvents such as ethyl acetate, methanol, petroleum ether, and chloroform. A response surface method (RSM) with a central composite design (CCD) statistical technique was applied to optimize the extraction process, employing three important extracting parameters such as extraction time (h), temperature (°C), and solvent composition (% v/v of methanol/water) to obtain the highest phenolic content. Total phenolic content (TPC) and antioxidant activity (IC₅₀ of extract’s DPPH radical scavenging activity) were used as response variables to find the influence of these extracting parameters. Among the various solvents used, methanol extract showed the highest contents of phenolics and the maximum level of antioxidant activity with a lower IC₅₀ value. The notable TPC and IC₅₀ value of the extract’s DPPH radical scavenging capacity were found to be 181.69 ± 0.20 mg GAE/g dry tissue and 60.13 ± 0.11 mg/mL, respectively, under the optimal conditions with a solvent composition of 71.61% (v/v) of methanol/water, extraction temperature of 42.52 °C, and extraction time of 24 h. The optimized extract of A. pavonina stem bark was further subjected to HPLC analysis, where six phenolic compounds, including coumarin, p-coumaric acid, chlorogenic acid, sinapic acid, gallic acid, and caffeic acid, were identified along with their respective quantities. Overall, the findings of this study uncover a low-cost analytical model for maximizing phenolic extraction from A. pavonina bark with enhanced antioxidant activity. Full article

Casparian strip membrane domain protein-like (CASPL) genes are key genes for the formation and regulation of the Casparian strip and play an important role in plant abiotic stress. However, little research has focused on the members, characteristics, and biological functions of the patchouli PatCASPL gene family. In this study, 156 PatCASPL genes were identified at the whole-genome level. Subcellular localization predicted that 75.6% of PatCASPL proteins reside on the cell membrane. A phylogenetic analysis categorized PatCASPL genes into five subclusters alongside Arabidopsis CASPL genes. In a cis-acting element analysis, a total of 16 different cis-elements were identified, among which the photo-responsive element was the most common in the CASPL gene family. A transcriptome analysis showed that p-hydroxybenzoic acid, an allelopathic autotoxic substance, affected the expression pattern of PatCASPLs, including a total of 27 upregulated genes and 30 down-regulated genes, suggesting that these PatCASPLs may play an important role in the regulation of patchouli continuous cropping obstacles by affecting the formation and integrity of Casparian strip bands. These results provided a theoretical basis for exploring and verifying the function of the patchouli PatCASPL gene family and its role in continuous cropping obstacles. Full article

Highly nutritious traditional plants which are rich in bioactive substances are attracting increasing attention. In this study, the nutritional value, chemical composition, biological activities, and feed indices of different parts of Millettia speciosa were comprehensively evaluated. In terms of its nutritional value, this study demonstrated that the leaves, flowers and seeds of M. speciosa were rich in elements and amino acids; the biological values (BVs) of these ingredients ranged from 85% to 100%, showing the extremely high nutritional value of this plant. GC-MS analysis suggested that the main chemical components of the flower volatile oil were n-hexadecanoic acid (21.73%), tetracosane (19.96%), and pentacosane (5.86%). The antibacterial activities of the flower and seed extracts were significantly stronger than those of the leaves and branches. The leaf extract displayed the strongest antifungal activities (EC₅₀ values: 18.28 ± 0.54 μg/mL for Pseudocryphonectria elaeocarpicola and 568.21 ± 33.60 μg/mL for Colletotrichum gloeosporioides) and were the least toxic to mouse fibroblasts (L929) (IC₅₀ value: 0.71 ± 0.04 mg/mL), while flowers were the most toxic (IC₅₀ value: 0.27 ± 0.03 mg/mL). In addition, the abundance of fiber, protein, mineral elements, and functional metabolite contents indicated the potential applicability of M. speciosa as an animal feed. In conclusion, as a traditional herbal plant used for medicinal and food purposes, M. speciosa shows potential for safe and multifunctional development. Full article

Ramie (Boehmeria nivea [L.] Gaud.), a nutritious animal feed, is rich in protein and produces a variety of secondary metabolites that increase its palatability and functional composition. Ethylene (ETH) is an important plant hormone that regulates the growth and development of various crops. In this study, we investigated the impact of ETH sprays on the growth and metabolism of forage ramie. We explored the mechanism of ETH regulation on the growth and secondary metabolites of forage ramie using transcriptomic and metabolomic analyses. Spraying ramie with ETH elevated the contents of flavonoids and chlorogenic acid and decreased the lignin content in the leaves and stems. A total of 1076 differentially expressed genes (DEGs) and 51 differentially expressed metabolites (DEMs) were identified in the leaves, and 344 DEGs and 55 DEMs were identified in the stems. The DEGs that affect phenylpropanoid metabolism, including BGLU41, LCT, PER63, PER42, PER12, PER10, POD, BAHD1, SHT, and At4g26220 were significantly upregulated in the leaves. Ethylene sprays downregulated tyrosine and chlorogenic acid (3-O-caffeoylquinic acid) in the leaves, but lignin biosynthesis HCT genes, including ACT, BAHD1, and SHT, were up- and downregulated. These changes in expression may ultimately reduce lignin biosynthesis. In addition, the upregulation of caffeoyl CoA-O-methyltransferase (CCoAOMT) may have increased the abundance of its flavonoids. Ethylene significantly downregulated metabolites, affecting phenylpropanoid metabolism in the stems. The differential 4CL and HCT metabolites were downregulated, namely, phenylalanine and tyrosine. Additionally, ETH upregulated 2-hydroxycinnamic acid and the cinnamyl hydroxyl derivatives (caffeic acid and p-coumaric acid). Cinnamic acid is a crucial intermediate in the shikimic acid pathway, which serves as a precursor for the biosynthesis of flavonoids and lignin. The ETH-decreased gene expression and metabolite alteration reduced the lignin levels in the stem. Moreover, the HCT downregulation may explain the inhibited lignin biosynthesis to promote flavonoid biosynthesis. In conclusion, external ETH application can effectively reduce lignin contents and increase the secondary metabolites of ramie without affecting its growth and development. These results provide candidate genes for improving ramie and offer theoretical and practical guidance for cultivating ramie for forage. Full article

Soursop possesses the largest fruit size of the Annona genus. However, this species is threatened by the Annonaceae fruit weevil (Optatus palmaris), which can cause the destruction of whole soursop fruits. Recently, the potential of semiochemicals for the management of this insect is highlighted, and its aggregation pheromone has been elucidated. This pheromone works well only when mixed with soursop volatiles. Thus, the aim of this research was to determine specific kairomone components to potentiate the aggregation pheromone of this Annonaceae fruit weevil. This task was carried out via volatilome analysis of soursop fruits, which was correlated with the biological activity of the identified volatiles. The GC–MS analysis of aroma collections of mature soursop fruits and flowers, determined using multivariate data analysis, confirmed a volatile differentiation between these organs. The volatile variation between fruits and flowers was reflected in weevils’ preference for mature fruits instead of flowers. Moreover, weevils’ response to soursop fruits increased with more mature fruits. This was correlated with volatile changes throughout the phenological stages of soursop fruits. The two volatiles most correlated with weevils’ attraction were benzothiazole and (E)-β-caryophyllene. These volatiles only evoked a response when mixed and potentiated the attraction of the aggregation pheromone. Thus, these two volatiles are active kairomone components with the potential for being used in combination with the aggregation pheromone of Annonaceae fruit weevils in field trials. Full article

Tropaeolum majus L. is a traditional medicinal plant with a wide range of biological activities due to the degradation products of the glucosinolate glucotropaeolin. Therefore, the goals of this study were to identify volatiles using gas chromatography–mass spectrometry analysis (GC-MS) of the hydrosols (HYs) isolated using microwave-assisted extraction (MAE) and microwave hydrodiffusion and gravity (MHG). Cytotoxic activity was tested against a cervical cancer cell line (HeLa), human colon cancer cell line (HCT116), human osteosarcoma cell line (U2OS), and healthy cell line (RPE1). The effect on wound healing was investigated using human keratinocyte cells (HaCaT), while the antibacterial activity of the HYs was tested against growth and adhesion to a polystyrene surface of Staphylococcus aureus and Escherichia coli. Antiphytoviral activity against tobacco mosaic virus (TMV) was determined. The GC-MS analysis showed that the two main compounds in the HYs of T. majus are benzyl isothiocyanate (BITC) and benzyl cyanide (BCN) using the MAE (62.29% BITC and 15.02% BCN) and MHG (17.89% BITC and 65.33% BCN) extraction techniques. The HYs obtained using MAE showed better cytotoxic activity against the tested cancer cell lines (IC₅₀ value of 472.61–637.07 µg/mL) compared to the HYs obtained using MHG (IC₅₀ value of 719.01–1307.03 μg/mL). Both concentrations (5 and 20 µg/mL) of T. majus HYs using MAE showed a mild but statistically non-significant effect in promoting gap closure compared with untreated cells, whereas the T. majus HY isolated using MHG at a concentration of 15 µg/mL showed a statistically significant negative effect on wound healing. The test showed that the MIC concentration was above 0.5 mg/mL for the HY isolated using MAE, and 2 mg/mL for the HY isolated using MHG. The HY isolated using MHG reduced the adhesion of E. coli at a concentration of 2 mg/mL, while it also reduced the adhesion of S. aureus at a concentration of 1 mg/mL. Both hydrosols showed excellent antiphytoviral activity against TMV, achieving100% inhibition of local lesions on the leaves of infected plants, which is the first time such a result was obtained with a hydrosol treatment. Due to the antiphytoviral activity results, hydrosols of T. majus have a promising future for use in agricultural production. Full article

The application of high-quality seeds ensures successful crop establishment, healthy growth, and improved production in both quantity and quality. Recently, biochar-based seed coating has been recognized as a new, effective, and environmentally friendly method to enhance seed quality, seedling uniformity, and nutrient availability. To study the impact of biochar coating on the surface mechanical properties of coated seeds, rice emergence and growth, and related physical and physiological metabolic events, laboratory experiments were performed on two water-saving and drought-resistance rice (WDR) varieties (Huhan1512 and Hanyou73) using biochar formulations with varying contents (20%–60%). The results showed that the appropriate concentration of biochar significantly improved emergence traits and seedling performance of the two rice varieties, compared to the uncoated treatment, and that the optimal percentage of biochar coating was 30% (BC30). On average, across both varieties, BC30 enhanced emergence rate (9.5%), emergence index (42.9%), shoot length (19.5%), root length (23.7%), shoot dry weight (25.1%), and root dry weight (49.8%). The improved germination characteristics and vigorous seedling growth induced by biochar coating were strongly associated with higher water uptake by seeds, increased α-amylase activity and respiration rate, and enhanced accumulation of soluble sugar and soluble protein. Moreover, the evaluation results of mechanical properties related to seed coating quality found that increasing the proportion of biochar in the coating blend decreased the integrity and compressive strength of the coated seeds and reduced the time required for coating disintegration. In conclusion, biochar coating is a cost-effective strategy for enhancing crop seed quality and seedling establishment. Full article

Peppers (Capsicum annuum L.), as a horticultural crop with one of the highest ascorbic acid contents, are negatively affected by detrimental environmental conditions both in terms of quality and productivity. In peppers, the high level of ascorbic acid is not only a nutrient substance but also plays a role in environmental stress, i.e., drought stress. When suffering from drought stress, plants accumulate dehydrins, which play important roles in the stress response. Here, we isolated an SK₃-type DHN gene CaDHN2 from peppers. CaDHN2 was located in the nucleus, cytoplasm, and cell membrane. In CaDHN2-silenced peppers, which are generated by virus-induced gene silencing (VIGS), the survival rate is much lower, the electrolytic leakage is higher, and the accumulation of reactive oxygen species (ROS) is greater when compared with the control under drought stress. Moreover, when CaDHN2 (CaDHN2-OE) is overexpressed in Arabidopsis, theoverexpressing plants show enhanced drought tolerance, increased antioxidant enzyme activities, and lower ROS content. Based on yeast two-hybrid (Y2H), GST-pull down, and bimolecular fluorescence complementation (BiFC) results, we found that CaDHN2 interacts with CaGGP1, the key enzyme in ascorbic acid (AsA) synthesis, in the cytoplasm. Accordingly, the level of ascorbic acid is highly reduced in CaDHN2-silenced peppers, indicating that CaDHN2 interacts with CaGGP1 to affect the synthesis of ascorbic acid under drought stress, thus improving the drought tolerance of peppers. Our research provides a basis for further study of the function of DHN genes. Full article

The objective of this study was to evaluate the synthesis of photosynthetic pigments, gas exchange, and photochemical efficiency of sour passion fruit genotypes irrigated with saline water under the conditions of the semi-arid region of Paraíba state, Brazil. The experiment was conducted at the experimental farm in São Domingos, PB. A randomized block design was adopted, in a 5 × 3 factorial scheme, with five levels of electrical conductivity of irrigation water—ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m⁻¹)—and three genotypes of sour passion fruit (Gigante Amarelo—‘BRS GA1’; Sol do Cerrado—‘BRS SC1’; and Catarina—‘SCS 437’. The increase in the electrical conductivity of irrigation water negatively affected most of the physiological characteristics of the sour passion fruit at 154 days after transplanting. Significant differences were observed between sour passion fruit genotypes when its tolerance was subjected to the salinity of irrigation water. There was an increase in the percentage of damage to the cell membrane with the increase in the electrical conductivity of irrigation water, with maximum values of 70.63, 60.86, and 80.35% for the genotypes ‘BRS GA1’, ‘BRS SC1’, and SCS 437’, respectively, when irrigated with water of 3.5 dS m⁻¹. The genotype ‘BRS Sol do Cerrado’ showed an increase in the synthesis of photosynthetic pigments when irrigated with water of 3.5 dS m⁻¹, with maximum values estimated at 1439.23 μg mL⁻¹ (Chl a); 290.96 μg mL⁻¹ (Chl b); 1730.19 μg mL−1 (Chl t); and 365.84 μg mL⁻¹ (carotenoids). An increase in photosynthetic efficiency parameters (F₀, Fm, and Fv) of the genotype ‘BRS Gigante Amarelo’ was observed when cultivated with water with high electrical conductivity (3.5 dS m⁻¹). Full article

Tomato fruit is an excellent model for evaluating calcium regulation in plants since it expresses symptoms of either calcium deficiency or calcium excess. Aiming to evaluate the structure of the vascular system and its interactions with calcium and calcium oxalate crystals (CaOx), fruits of Lycopersicon pimpinellifolium were studied. Calcium levels were evaluated in basal, median, and distal pericarp portions, which were also analyzed under a light microscope to describe the structure. The L. pimpinellifolium pericarp shows idioblasts with calcium oxalate crystals. Vascular bundles of the basal pericarp show large transverse sections and abundant xylem vessels. The vascular bundles were smaller in the distal pericarp, and the xylem showed fewer and narrower vessels. The terminal bundles often consisted exclusively of phloem. Despite the differences observed in vascular bundle composition, the density of the vascular system was uniform in the pericarp as a consequence of bundle ramifications that occur at distal portions. The calcium concentration and crystal idioblasts decrease towards the apex of the fruit. The reduction in the xylem:phloem ratio seems to determine the low calcium concentration in the distal fruit portion. Full article

This study emphasizes the importance of seed quality in the context of yield formation. Based on the research data, this paper emphasizes the role of proper diagnosis of seed-borne pathogens in ensuring high and stable grain yields. Particular attention is paid to the study of the effect of the treatment of mother plants with fullerenol-based nanopreparations on the qualitative characteristics of spring barley seeds. The results showed that such treatment contributes to the increase in varietal purity, weight of 1000 grains as well as to the increase of nutrient and moisture reserves in seeds. Phytopathological analysis confirmed the presence of various diseases such as Alternaria, helminthosporiosis, fusarium, mold and mildew on the seeds. However, some samples showed a high resistance to pathogens, presumably due to the use of carbon nanopreparations. These results open new perspectives for the development of strategies to improve barley yield and disease resistance through seed optimization. Full article

Sex segregation increases the cost of Carica papaya production through seed-based propagation. Therefore, in vitro techniques are an attractive option for clonal propagation, especially of hermaphroditic plants. Here, we performed a temporal analysis of the proteome of C. papaya calli aiming to identify the key players involved in embryogenic callus formation. Mature zygotic embryos used as explants were treated with 20 μM 2,4-dichlorophenoxyacetic acid to induce embryogenic callus. Total proteins were extracted from explants at 0 (zygotic embryo) and after 7, 14, and 21 days of induction. A total of 1407 proteins were identified using a bottom-up proteomic approach. The clustering analysis revealed four distinct patterns of protein accumulation throughout callus induction. Proteins related to seed maturation and storage are abundant in the explant before induction, decreasing as callus formation progresses. Carbohydrate and amino acid metabolisms, aerobic respiration, and protein catabolic processes were enriched throughout days of callus induction. Protein kinases associated with auxin responses, such as SKP1-like proteins 1B, accumulated in response to callus induction. Additionally, regulatory proteins, including histone deacetylase (HD2C) and argonaute 1 (AGO1), were more abundant at 7 days, suggesting their role in the acquisition of embryogenic competence. Predicted protein–protein networks revealed the regulatory role of proteins 14-3-3 accumulated during callus induction and the association of proteins involved in oxidative phosphorylation and hormone response. Our findings emphasize the modulation of the proteome during embryogenic callus initiation and identify regulatory proteins that might be involved in the activation of this process. Full article

A new diatom genus Cymbosellaphora Kulikovskiy, Glushchenko, Genkal and Kociolek gen. nov., was described with species Cymbosellaphora vietnamensis Glushchenko, Kulikovskiy and Kociolek sp. nov. C. vietnamensis sp. nov. was described from Vietnam and characterized by the presence of morphological features such as valves with naviculoid symmetry, slight dorsiventrality, the presence of tectula as pore occlusions, uniseriate striae, and a very broad mantle. Four species were transferred to the new genus. These are C. absoluta comb. nov., C. circumborealis comb. nov., C. geisslerae comb. nov., and C. laterostrata comb. nov. Previously, these species were members of genera Navicula Bory, Sellaphora Mereschkowsky, and Naviculadicta Lange-Bertalot. The taxonomic history of these species and genera are discussed. The tectulum is known only from the cymbelloid diatoms, and our new genus is placed within the Cymbellaceae. The presence of a tectulum demonstrates that these species cannot be placed in Sellaphora, as indicated in the literature. The recent proposal to transfer a large number of species with different morphologies to the genus Sellaphora is also discussed. Additionally, we compare pore occlusions with tectula between different genera of the Cymbellaceae with naviculoid symmetry. Full article

Obesity has become a major health issue worldwide and obese individuals possess higher levels of adipose tissue when compared with healthy individuals. Obesity is highly associated with the development of different chronic diseases, such as diabetes, cardiovascular diseases, hypertension, cancers, etc. Previous studies established that anthocyanin compounds play an important role in attenuating obesity-related consequences. Among various anthocyanin compounds, cyanidin-3-O-β-glucoside (C3G) is the most important component and is widely distributed in various colored edible plant materials, especially berries, cherries, black rice, purple corn, etc. In recent decades, several studies have reported the therapeutical properties of C3G. C3G has various biological properties and health benefits, such as antioxidant, antimicrobial, anti-inflammatory, antidiabetic, anti-obesity, neuroprotective, anticancer, etc. In this review, we summarized the in vitro and in vivo studies in relation to the role of C3G in obesity-related complications. Several mechanistic studies demonstrated that C3G maintains the metabolism of glucose, fatty acids, and lipids by regulating different genes and signaling pathways. It could be concluded that the consumption of C3G protects healthy individuals from obesity-related issues by maintaining body weight and regulating their metabolism and energy balance. This review provides some important signaling pathways/targets of C3G to facilitate the prevention and treatment of obesity, leading to the development of important food supplements. Full article

Phosphorus (P) is a major limiting factor for legume and symbiotic nitrogen fixation (SNF). Although overall adaptations of legumes to P supplementation have been extensively studied in connection with inorganic P, little information is currently available regarding nodulation or SNF responses to organic P (Po) in hydroponics. We investigated the mineral and carbon metabolism of Po-induced nodules of two contrasting faba bean varieties grown hydroponically under inorganic P (Pi), viz., in P-deficient (2 µM KH₂PO_4, −Pi), sufficient-P (200 µM KH₂PO₄, +Pi), and phytic acid (200 µM, Po) conditions, and were inoculated with Rhizobium leguminosarum bv. viciae 3841 and grown for 30 days. The results consistently reveal similar growth and biomass partitioning patterns between +Pi and Po, with both varying substantially from −Pi. In comparison, +Pi and Po observed equivalent accumulations of overall elemental P concentrations, with both increasing by 114 and 119%, respectively, relative to −Pi. A principal component analysis on metabolites showed a clear separation of the −Pi treatment from the others, with +Pi and Po correlating closely together, highlighting the nonsignificant differences between them. Additionally, the δ¹⁵N abundance of shoots, roots, and nodules was not significantly different between treatments and varieties and exhibited negative δ¹⁵N signatures for all tissues. Our study provides a novel perspective on mineral and carbon metabolism and their regulation of the growth, functioning, and reprogramming of nodules upon phytate supply. Full article