Search Results (2,579)

The present study aimed to characterize soybean pressed fiber obtained through wet fractionation of green biomass and evaluate the effects of variety and vegetation window on its composition and valorization potential. Four soybean varieties (Advisor, Bólyi 612, Isidor, and Pannónia kincse) were investigated across two distinct vegetation windows using anatomical, cell wall, biochemical, and pigment analyses. Significant variety-dependent differences were observed in several anatomical traits related to biomass quality. Isidor exhibited the greatest leaf blade thickness, while Advisor showed favorable stem structural characteristics and enhanced cuticle development. Cell wall analysis revealed significant differences in xylan, arabinan, and Klason lignin between vegetation windows, while glucan content was affected by both variety and vegetation window, with the highest value observed in Advisor during the first vegetation window. Photosynthetic pigment composition remained relatively stable among varieties and vegetation windows. Because the two vegetation windows occurred during different calendar periods, the observed differences may reflect both plant developmental status and seasonal environmental conditions and cannot be exclusively attributed to harvest timing. This one-year exploratory study provides baseline information on soybean pressed fiber as a potential secondary biomass resource. Further multi-year and multi-environment studies are required to assess the stability and environmental consistency of these findings. Full article

The current challenges associated with the conservation and restoration of plant biodiversity make it necessary to test new biotechnological approaches. Optimizing the stages of clonal micropropagation using synthetic growth biostimulants—protatranes (1,2,3)—enables the targeted modification of physiological processes in plants. This increases their stress resistance, stimulates development, and reduces the cost of the final product. In this paper, the stimulating effect of the protatran (1), which we have named “crezacin”, on the processes of in vitro rooting and acclimatization to ex vitro conditions in microplants of the rare wild species Lilium pensylvanicum Ker Gawl was studied. No effect of crezacin and α-naphthylacetic acid on the development and growth of the microbulb during the rooting stage was detected. Crezacin at a concentration of 1.0 mg/L inhibited root elongation, but did not affect root number. Using α-naphthylacetic acid at a concentration of 0.93 mg/L was ineffective in inducing in vitro rhizogenesis. The survival rate of regenerated plants cultivated on media supplemented with crezacin was found to be 100%. The positive effect of crezacin on the content of photosynthetic pigments in the leaves of regenerated plants was also demonstrated. The addition of ultra-low concentrations (0.001–0.1 mg/L) of crezacin increased pigment content by up to 1.5 times (p < 0.05) compared to the control group. The increase in chlorophyll and carotenoid levels upon the addition of crezacin to the culture medium significantly facilitated the transition from a heterotrophic to an autotrophic mode of nutrition when microplants were transplanted into a soil substrate. Further research on clonal micropropagation of rare plant species and horticultural crops will be conducted using protatranes 2 and 3. Full article

The study evaluated the potential of low-dose foliar melatonin (MT) treatments to alleviate chilling injury in cucumber plants, with a particular focus on mimicking sudden spring frosts in open-field cultivation. Cucumber seedlings were sprayed with MT solutions at 0.1, 1, and 10 mg L⁻¹ (0.4, 4, 40 µM respectively), then subjected to a controlled chilling regime (4 °C for 72 h). A set of biochemical and physiological parameters was assessed, including stem elongation, leaf area, tissue water content, photosynthetic pigment concentrations, malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) accumulation, antioxidant enzyme activities, and soluble carbohydrate profiles. In addition, the thermostable fraction of chlorophylls a and b was determined as an indicator of photosynthetic system integrity; this parameter substantially increased under MT treatment, particularly at 1 and 10 mg L⁻¹, despite an overall reduction in total pigment content. The results demonstrated that MT pretreatment, especially at 1 mg L⁻¹, significantly mitigated chilling-induced growth inhibition, preserved chloroplast integrity, and reduced membrane lipid peroxidation. Moreover, MT promoted the accumulation of osmo- and cryoprotective sugars, contributing to improved cellular homeostasis under low temperature. These key findings indicate that low-dose MT priming is a promising, nature-derived strategy to enhance the tolerance of cucumber to acute chilling events, supporting the development of sustainable and organic-friendly approaches for spring frost protection. Full article

Protected horticultural crops are commonly produced at high planting densities and have short production cycles; imbalances in water and fertilizer supply can rapidly affect plant vigor, yield, and quality. Non-destructive diagnostic methods are therefore needed to characterize plant nutritional status under greenhouse conditions. Spectral imaging can simultaneously capture spatial and spectral information associated with pigments, water status, tissue structure, and canopy phenotype. It does not directly detect nutrient ions; rather, it captures physiological and structural responses that may be associated with nutrient status and may also be influenced by water deficit, disease, temperature, salinity, phenology, and genotype. This review focuses on crops grown in soil, substrate, and hydroponic systems under greenhouse conditions. Studies conducted in vertical farms, growth chambers, and open fields are included only as supplementary references for sensor selection, model calibration, and inspection methods. This article synthesizes diagnostic indicators for nitrogen, phosphorus, and potassium, together with their associated physiological responses and spectral characteristics; compares the performance of hyperspectral, multispectral, and machine learning methods at the leaf, plant, and canopy scales; and examines fixed measurement, stop-and-go mobile inspection, continuous motion imaging, and autonomous plant revisitation. Existing studies have established a solid foundation for nutrient content retrieval, deficiency identification, and mobile monitoring. However, several challenges remain inadequately addressed under continuous inspection conditions, including radiometric–geometric joint calibration, plant identity preservation, acquisition of multi-element chemical truth values, model generalization across growth stages and greenhouse types, and long-term performance evaluation. Future work should refine standardized protocols for dynamic data collection and water–fertilizer environmental control, integrate mechanistic constraints with data driven approaches, and incorporate plant re-identification, spatiotemporal registration, uncertainty quantification, and online calibration. These efforts will contribute to constructing a long-term stable and comparable nutritional diagnostic system, thereby advancing the transition of facility vegetable nutritional monitoring from single-time static measurements toward continuous, traceable, and autonomously patrolled systems that may ultimately support precision irrigation and fertilization management after appropriate independent validation. Full article

High-intensity blue light is a powerful regulatory signal for plants, but its excess induces oxidative stress requiring rapid diagnosis. This study evaluated the potential for early detection of changes in the spectral characteristics of microgreen canopy cover caused by high-intensity blue light (PPFD 2500 µmol·m⁻²·s⁻¹, 12 h) in five species of microgreens (Helianthus annuus, Pisum sativum, Eruca sativa, Hordeum vulgare, Raphanus sativus ‘Sango Purple’) using hyperspectral imaging (450–950 nm) and machine learning. A Random Forest model trained on 85 vegetation indices classified light stress with high accuracy (Accuracy > 93%, Kappa > 0.87, F1-score > 93%) and detected spectral changes characteristic of light stress as early as 1–3 h of exposure. SHAP analysis identified carotenoid-sensitive indices (PRI, CCI, PRICI2) and chloroplast movement and stress indices (CMI, LSI_Red, LSI_Norm, Carter5) as the most informative predictors. It is assumed that the primary mechanism underlying early spectral changes was chloroplast avoidance rather than pigment degradation, as confirmed by the reversibility of canopy bleaching, rapid recovery of maximum quantum yield of photosystem II, and unchanged chlorophyll and carotenoid contents. Sunflower and radish were the most sensitive species to high-dose blue light, while barley was the least sensitive. LSI_Red was identified as a reliable qualitative marker of light stress that does not require a control sample, simplifying its use in automated monitoring systems. These findings demonstrate the effectiveness of hyperspectral phenotyping for non-invasive, rapid diagnosis of light stress in microgreens, providing a tool for optimising lighting regimes in controlled environment agriculture. Full article

Objective: Saline–alkali stress (composed of neutral and alkaline salts) severely constrains soybean productivity. Although nicotinamide can enhance plant salt tolerance, its most effective concentration and molecular basis in soybean remain unclear. This study aimed to systematically investigate the regulatory effect of exogenous nicotinamide on soybean saline–alkaline tolerance and to identify its candidate genes and putative mechanisms under salt-stressed conditions. Methods: Soybean cultivar ‘Hefeng 25’ seedlings were exposed to 200 mmol/L mixed salt stress and treated with nicotinamide at 0 (CK), 10, 50, and 200 mg/L. Growth parameters, ROS levels, ion contents, photosynthetic pigments, osmoregulatory substances, and antioxidant enzyme activities were measured. Transcriptome sequencing and RT-qPCR were performed to identify differentially expressed genes (DEGs), followed by enrichment analysis. Results: Exogenous nicotinamide significantly improved soybean saline–alkaline tolerance relative to the salt-stressed CK group, with 50 mg/L (SA2) showing the most pronounced physiological improvements among all tested concentrations. SA2 treatment enhanced plant height, biomass, K+ content, and antioxidant enzyme activities while reducing Na+ accumulation and ROS levels compared with CK. Transcriptome analysis identified PM1 as the shared gene across the five non-most effective comparisons. Enrichment analysis implicated DEGs primarily in ko03110 (chaperones and folding catalysts), ko00199 (cytochrome P450), and ko04141 (protein processing in the endoplasmic reticulum). RT-qPCR confirmed that PM1, P450 genes (CYP74A1, CYP83D1), HSPs (HSP23, HSP18), and ROS scavengers (NAC1, GSTU43) were upregulated under non-most effective doses (SA1/SA3) but downregulated to levels comparable to the stressed CK in SA2; conversely, SA2 specifically restored the expression levels of stress-repressed WRKY57 and LBD15. Transcriptomically, SA2 exhibited a profile most similar to the saline–alkali-stressed CK group, with the fewest number of differentially expressed genes among all treatments, whereas non-optimal nicotinamide concentrations were associated with extensive transcriptional changes in ER protein processing, detoxification-related, and oxidative stress-related pathways. The limited transcriptional changes in SA2 indicate greater transcriptional similarity to the stressed control, which paralleled its superior physiological performance. Conclusions: Nicotinamide effectively alleviates soybean saline–alkaline stress at 50 mg/L, with the most significant physiological benefits and the fewest transcriptional changes relative to the stressed control. The non-most effective nicotinamide concentrations show extensive stress-related transcriptional reprogramming in protein folding, detoxification, and stress-response pathways relative to the salt-stressed control, putatively implicating ER stress, detoxification, and oxidative stress-related responses at the transcript level, with PM1 acting as a potential candidate transcriptional marker of dose-dependent transcriptional regulation under saline–alkali stress. Full article

Saline–alkali stress severely restricts leafy vegetable growth by impairing photosynthesis, ion homeostasis, and oxidative balance. This study investigated whether exogenous melatonin could alleviate saline–alkali stress in pakchoi (Brassica rapa subsp. chinensis) through coordinated protection of photosynthetic electron transport, ionic balance, and antioxidant defense. Pakchoi plants were subjected to four treatments: normal nutrient solution (CK), 100 μM melatonin (MT), 100 mM mixed saline–alkali stress with NaCl:NaHCO₃ at 2:1 (SAS), and saline–alkali stress plus melatonin (SAS+MT). After 7 d, growth traits, gas exchange, chlorophyll fluorescence, OJIP transients, ion contents, osmotic adjustment, oxidative damage, and antioxidant enzyme activities were analyzed. Saline–alkali stress markedly inhibited growth, reduced photosynthetic pigment contents and gas exchange, impaired PSII photochemical performance, disrupted ion balance, and increased ROS accumulation and membrane damage. Compared with SAS, SAS+MT increased net photosynthetic rate (Pn) by 66.2%, effective quantum yield of PSII [Y_(II)] by 56.0%, electron transport rate (ETR) by 57.9%, and the performance index on absorption basis (PI_ABS) from 0.80 to 1.80. Melatonin also reduced Na⁺ content by 38.7%, increased the K⁺/Na⁺ ratio from 1.0 to 2.2, and enhanced superoxide dismutase (SOD),peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activities by 20.5%, 24.4%, 29.2%, and 33.3%, respectively. These results indicate that melatonin alleviates saline–alkali injury in pakchoi by maintaining PSII electron transport, improving ion homeostasis, and strengthening antioxidant defense. Full article

The genus Renanthera is valued for its fiery-red floral coloration and distinctive spider-like floral architecture; however, the molecular mechanisms underlying floral organ specialization and perianth color differentiation remain poorly understood. In this study, using integrated morphological, transcriptomic, and metabolomic analyses of R. coccinea, we found that the cell types of the dorsal and lateral perianth organs were broadly similar but clearly distinct from those of the lip and the column. Developmentally, the organ-specific expression patterns of AGAMOUS-LIKE6-1/2 (AGL6-1/2), APETALA3-1/2 (AP3-1/2), and AGAMOUS (AG) were consistent with the conserved orchid floral organ identity model. Furthermore, lip-enriched expression of brassinosteroid-responsive RING H2 (BRH1) and flavin-containing monooxygenase YUCCA10 (YUC10) suggests that brassinosteroid- and auxin-associated pathways may contribute to lip specialization, especially spur development. Regarding pigmentation, high expression of flavonoid 3′-hydroxylase (F3′H) was associated with a cyanidin-dominated anthocyanin profile. The color divergence among the dorsal sepal, petals, and lateral sepals was associated with differential expression of UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT), which was co-expressed with plant U-box protein 9 (PUB9) and carbon catabolite repressor 4 (CCR4), associated with distinct patterns of pigment modifications. These findings provide a molecular framework for understanding floral organ development and color patterning in R. coccinea and candidate genes for future validation and molecular breeding in Renanthera. Full article

Myrtus communis L. is an aromatic and medicinal plant commonly used in the pharmaceutical, food, and cosmetic industries for its bioactive compounds. Temporary immersion systems (TISs) are an efficient and cost-effective in vitro propagation method for enhancing biomass and secondary metabolite production under controlled conditions. This study aimed to compare the effect of three different TIS bioreactors (SETIS™, Plantform™, and ElecTIS) and a conventional semisolid culture on relative growth rate (RGR), photosynthetic pigments, stomatal function and terpene content. The results showed that all bioreactors increased biomass production, with the highest RGR achieved in ElecTIS (7.1) after 28 days of culture. SETIS^TM induced 80% rooting and better stomatal density and functionality, resulting in a 98% survival rate of plants in acclimatization. Moreover, chlorophylls and carotenoids were significantly enhanced during rooting, particularly in SETIS™ and Plantform™. GC-MS analysis identified 14 volatile compounds, with myrtenyl acetate, linalool, and α-pinene as the dominant constituents. Rooted shoots cultured in Plantform™ and SETIS™ accumulated the highest terpene concentrations (341.5 and 326.4 μg g⁻¹ FW, respectively), which exceeded those of semisolid cultures. These findings demonstrate that TIS bioreactors, particularly SETIS™, represent a promising tool for the efficient production of biomass and terpenes, depending on the selection of the appropriate culture conditions, bioreactor type, and plant development stage. Full article

Rind color is an important quality trait in zucchini (Cucurbita pepo). As a core transcription factor in plant pigment biosynthesis, APRR2 plays a conserved yet mechanistically diverse regulatory role in the formation of rind color in various vegetables. However, the APRR2 transcription factor regulates rind color but has not been systematically identified in C. pepo. In this study, 50 APRR2 genes were defined by the presence of the conserved REC domain verified. These genes were identified and found to be unevenly distributed across the 20 chromosomes, primarily expanded through tandem duplication events. Phylogenetic and structural analysis classified these genes into three distinct subgroups, all featuring the conserved REC domain essential for pigment regulation but exhibiting variations in motifs and intron–exon structures. Promoter analysis revealed abundant light-responsive, hormone-responsive and stress-responsive elements that may contribute to environmental adaptation and photomorphogenesis. Crucially, transcriptome analysis during rind development (0 and 10 days after pollination) in green (GR) and white (WR) rind lines demonstrated profound functional divergence. Expression clusters indicated temporal shifts in metabolism and enriched “circadian rhythm-plant” and “photosynthesis” pathways in WR at 0 DAP. Specific APRR2 genes were tightly correlated with rind color. qPCR validation of the 24 selected APRR2 genes classified them into four trend groups based on the direction of expression change at 10 DAP. In total, 14 genes were upregulated in both GR and WR, 6 were downregulated in both lines, 1 was upregulated in GR but downregulated in WR, and 3 were downregulated in GR but upregulated in WR. Furthermore, protein–protein interaction prediction and yeast two-hybrid (Y2H) assays detected a physical interaction in yeast between a core APRR2 protein and a bHLH62 transcription factor, suggesting a potential interaction that may be involved in rind color regulation, pending in planta validation. The study first identified the members of the APRR2 gene family in C. pepo and conducted a bioinformatics analysis on them. The study establishes the molecular basis of APRR2 function and offers valuable resources for breeding improved C. pepo varieties. Full article

Replacing synthetic colorants with natural alternatives requires source-specific extraction strategies because pigment classes differ in polarity, pH response and thermal stability. This first-pass screening focused on six plant and agro-food matrices: red cabbage, Iris germanica petals, dragon fruit, orange peel, spent coffee grounds and pine bark. Each matrix was subjected to twelve extraction treatments combining water, ethanol, acetone 30%, acid/base modifiers, boiling water, freezing and ultrasound assistance. Extracts were evaluated by visible transmittance spectroscopy from 360 to 740 nm, operationally transformed to apparent optical attenuation according to Aapp (λ) = −log10 [%T (λ)/100] only where measured %T exceeded 0.01; this signal may include both absorption and light scattering, and converted to CIELAB coordinates under D65/10° conditions. The combined spectral and colorimetric approach separated the extracts into red-purple and yellow-brown groups. Red cabbage and Iris showed anthocyanin-like behaviour, dragon fruit showed a betalain-compatible magenta response, orange peel showed carotenoid-compatible short-wavelength attenuation, and coffee grounds and pine bark generated broad brown-yellow profiles. Pigment-family assignments remain putative because chromatographic identification was not performed. This study is explicitly intended as a proof-of-concept descriptive mapping step rather than as a statistically validated extraction optimisation. Because every matrix–treatment combination was prepared once, all comparisons in this article describe the observed screening preparations only; they do not estimate reproducible treatment effects, confidence intervals or statistical significance. The previous equal-weight low-L*/high-C*ab intensity score has been removed from the revised analysis. No extraction yield, recovery percentage, mass balance, purity, pigment concentration or application performance was measured; accordingly, this study describes the optical appearance of the obtained extracts and does not quantify colorant recovery. Visible transmittance, apparent optical attenuation and CIELAB coordinates support only literature-informed class-level hypotheses and cannot identify a pigment family or individual compound. Full article

High temperatures (HTs) severely constrain the growth and development of Elodea nuttallii, highlighting the need for effective mitigation strategies to maintain its ecological functions. This study investigated the effects of exogenous glycine (Gly) on E. nuttallii under high-temperature stress (HTS). Plants were assigned to three groups: (i) CK (no stress, 25 °C, no Gly), (ii) HT (HTS, 35 °C, no Gly), and (iii) HT+Gly (HTS, 35 °C, with Gly). HTS significantly reduced the plant height and fresh weight, chlorophyll fluorescence parameters (F_v/F_m, YII, and NPQ), photosynthetic pigments (Chl-a, Chl-b, and Car), CAT activity, and 6-BA content, while increasing the ABA, IAA, and GA levels. Exogenous Gly application substantially alleviated these adverse effects. Compared with the HT group, Gly increased F_v/F_m, YII, Chl-a, and Chl-b by 16.67%, 17.34%, 86.72%, and 72.22%, respectively, on day 4. Gly also strengthened antioxidant defense by increasing APX activity to as much as 2.38-fold that of the HT group and reducing H₂O₂ content by 29.03% on day 6. In addition, Gly restored a more balanced phytohormone profile. These findings indicate that exogenous Gly can substantially improve the HT tolerance of E. nuttallii and may provide a practical approach for enhancing macrophyte resilience under high-temperature conditions. Full article

This study investigates the formulation of a natural cosmetic product using pigment derived from annatto (Bixa orellana) seeds, which is widely utilised as a natural colourant in food, pharmaceutical, and cosmetic applications. The objective was to optimise pigment extraction using supercritical fluid extraction (SFE) and evaluate its suitability for cosmetic formulation. Extraction was performed using supercritical carbon dioxide and ethanol as a co-solvent over a range of operating conditions to identify parameters that provided high pigment recovery. High extraction yields were obtained under several operating conditions, with favourable performance achieved at relatively low temperature, pressure, and flow rate. The annatto pigment extract was incorporated as a colouring agent into a naturally derived lipstick formulation containing beeswax and plant-derived oils. The developed formulation demonstrated satisfactory performance and appearance, confirming the suitability of annatto-derived pigment. Colour analysis indicated that processing conditions influenced extraction yield but did not significantly affect pigment colour or final product appearance. Overall, the results support the use of annatto pigment extracted via SFE as a viable and sustainable option for natural cosmetic product development. Full article

Biodegradable alginate films containing silver nanoparticles (AgNPs) are being increasingly investigated as active agricultural materials (e.g., antimicrobial mulches) and active food packaging. However, since these materials ultimately degrade in soil after use, assessing their environmental compatibility and potential phytotoxicity upon release is crucial. The aim of this study was to synthesize films containing AgNPs in sodium alginate using xylose as a reducing agent and to determine their effect on culturable rhizosphere microorganisms and selected biochemical parameters in young arugula (Eruca vesicaria L. subsp. sativa) plants. Alginate films containing three nominal AgNP loadings (50, 100, and 150 mg L⁻¹) and a control film without AgNPs were synthesized. The films were cut into square pieces (4 cm²) and placed in 0.076 L multipots filled with peat substrate, into which arugula seeds were sown. During the experiment, the abundance of culturable rhizosphere bacteria and fungi was determined, and the young arugula plants were subjected to biochemical analyses. The results showed that the AgNP-containing films did not significantly affect the abundance of bacteria and fungi in the rhizosphere under the conditions tested. The tested films also did not markedly alter the measured parameters in the tissues of young arugula plants, including ascorbic acid, photosynthetic pigments, sugars, dietary protein, and glutathione. However, they reduced phenolic content, altered antioxidant activity, and led to detectable silver accumulation in plant tissues, especially at the highest nominal AgNP loading (150 mg L⁻¹). These findings indicate limited but selective biochemical effects during the early growth stage of arugula rather than a complete absence of plant response. Full article

Plant-derived methane (CH₄) has already been reported, but the factors that regulate its production are not fully documented. Few studies have considered the effects of blue light on plant-derived CH₄, but the role of salicylic acid in the process has not been studied. We examined the effects of two blue light levels (0 and 4 mW cm⁻²) and two salicylic acid concentrations (0 and 100 μL of 1 mM solution every other day) on canola (Brassica napus) growth and CH₄ emissions by growing plants under the experimental conditions for 21 days. Blue light raised CH₄ emission by 184% and increased stem height, leaf area ratio, shoot–root mass ratio, nitrogen balance index, leaf water potential, soil water potential, and leaf water content, but decreased stem diameter, plant biomass, specific leaf mass, net CO₂ assimilation, photochemical quenching, photosynthetic pigments, flavonoids, and anthocyanins. Salicylic acid did not have a significant effect on plant traits. Methane had both positive and negative relationships with plant traits; for example, CH₄ was negatively correlated with plant dry mass (r = −0.776, p = 0.003), protective compounds (r = −0.914, p = 0.000) and stomatal density (r = −0.677, p = 0.016), but positively correlated with nitrogen balance index (r = 0.621, p = 0.031). Our findings suggest that blue light negatively affects canola growth but increases CH₄ emissions, whereas the application of salicylic acid, as described in this study, was insufficient for mitigating stress in plants. Full article