Search Results (1,064)

The naphthazarins shikonin and alkannan are strongly chromogenic, dark red enantiomers, each of which has biological activity, that are found primarily in the plant family Boraginaceae. These compounds and their many chemical metabolites, derivatives, oligomers, and analogs (“shikonoids”) are an important group of phytochemicals, utilized since antiquity as components of dyes, traditional medicines, and food and cosmetics. They are now recognized for their potent anti-inflammatory and regulatory activity on a variety of molecular signaling pathways in humans. Since many Boraginaceae species are overly exploited or endangered, we developed a pilot-scale in vitro shikonoid production system using Plagiobothrys arizonicus (Gray) Greene ex A.Gray, the Arizona popcorn flower, native to the southwestern USA and the Sonoran floristic province in the Madrean region of Mexico. Aseptic root cultures were initiated from fresh leaf tissue and stimulated to continuously produce shikonoids in liquid shake cultures layered under paraffin oil from which the shikonoids were extracted and concentrated. The crude, red extracellular product from these rapidly expanding root masses was also fractionated by Centrifugal Counter-Current Chromatography (CCC) into its component shikonin derivatives. A number of these shikonoids profoundly up-regulated detoxification and antioxidant proteins (phase 2 enzymes) and inhibited inflammation in mammalian cell bioassay systems. This prototype shikonoid production methodology can be readily scaled to either batch or chemostat culture. Full article

Potatoes have low nitrogen (N) use efficiency due to their shallow root systems, which results in nitrate loss and reduced yield. The objective of this study was to determine physiological parameters, yield, and quality components in three potato varieties subjected to N deficiency in a greenhouse, as there are few previous studies on the relationship between N deficiency and physiological parameters. The control plants were fertilized twice with 27% calcium ammonium nitrate, while the stressed plants were not fertilized. Chlorophyll content (SPAD), biomass, N, and leaf area showed highly significant differences (p value < 0.05) between the control and stressed plants, the latter showing higher photosynthetic activity. Agria cv. obtained the highest SPAD value (T0: 47.93, T1: 44.45; T2: 40.18) under stress. In tubers, the concentrations of N, amino acids, vitamin C, and phenols were higher in the control plants, and Agria exhibited the greatest reduction under stress conditions. Production was reduced the most in Kennebec, with 29.22%, compared to Agria with 15.73% and Monalisa with 26.58%. The Agria variety under N deficiency showed the lowest values of nutritional compounds such as vitamin C. Physiological parameters such as photosynthetic activity showed significant correlations with tuber quality parameters such as vitamin C, amino acids, and macro- and microelements. These parameters may be useful for stress identification, as well as for the selection of more N-deficiency-tolerant parents in potato breeding programs. Upcoming studies and investigations will seek to validate the parameters assessed in field trials. Full article

Background/Objectives: The aim of the present study was to evaluate the antimicrobial, antibiofilm, anti-quorum sensing, and cytotoxic activities of the essential oils extracted from the leaves of Dorystoechas hastata Boiss & Helder. ex Bentham (Lamiaceae) (DHL-EO) as well as to determine the chemical composition of the essential oils obtained from both the leaves and roots. Methods: The essential oils of the root and leaf were extracted by the hydrodistillation method. The chemical composition of the two oils was determined by Gas Chromatography–Mass Spectrometry (GC-MS). The antimicrobial activity of DHL-EO was determined against Gram-positive, Gram-negative bacteria, and various Candida species using the broth microdilution method. Pseudomonas aeruginosa PAO1 and Chromobacterium violaceum ATCC 12472 were used for antibiofilm and anti-quorum sensing activities, respectively. The cytotoxic activity of the DHL-EO was examined by MTT assay. Results: Eucalyptol (21.3%), 2-bornanone (17.0%), and α-pinene (10.3%) were the main compounds of the DHL-EO. The root essential oil (DHR-EO) had trans-ferruginol (19.2%), guaiol (14.1%), and ar-abietatriene (14.0%) as the main components. The DHL-EO displayed weak and moderate antimicrobial activity. The DHL-EO showed moderate antibacterial activity against Staphylococcus aureus ATCC 29213 (methicillin-susceptible, MSSA) and S. aureus ATCC 43300 (methicillin-resistant, MRSA), with a MIC value of 12.5 mg/mL. The DHL-EO exhibited the strongest antifungal activity against Candida parapsilosis RSKK 994, with a MIC value of 0.78 mg/mL. It also demonstrated antifungal activity against C. parapsilosis ATCC 22019 and Candida krusei RSKK 3016, with MIC values of 3.12 mg/mL. The DHL-EO showed antibiofilm activity in a concentration-dependent manner, particularly at higher concentrations, and inhibited violacein production in a dose-dependent manner, with anti-quorum sensing activity. The DHL-EO displayed moderate cytotoxic activity against MCF-7 (IC₅₀: 110.3 μg/mL) and A549 (IC₅₀: 120.4 μg/mL) cell lines. Conclusions: The chemical composition of DHL-EO and DHR-EO showed qualitative and quantitative differences from each other in the present study. The essential oil of the leaves showed moderate cytotoxic and antibacterial activities. Full article

Salinity is one of the major problems limiting plant growth, development, survival, yield, and quality. Climate change and increasing salinity levels force a concentration on sustainable production systems. Therefore, this study aimed to determine the effects of different doses of gibberellic acid (GA₃) (0, 150, and 300 mg/L) and salicylic acid (SA) (0, 0.25, and 0.50 mM) priming on some morphological and antioxidant enzyme activities of silage maize (Zea mays L.) seedlings exposed to salinity stress. Four different NaCl (0, 75, 150, and 225 mM) concentrations as salt stress and three different doses of both SA and GA₃ were investigated. The data obtained were subjected to analysis of variance according to a randomized complete block design using a factorial experimental design with four replications per treatment in 3 L pots. The results showed that GA₃ and SA priming had statistically significant effects on all investigated traits under different salt concentrations (except water content). Findings revealed that shoot, root, and leaf development, as well as antioxidant enzymes, were suppressed by salinity stress. The silage maize plant was statistically significantly affected starting from the lowest dose of 75 mM, depending on salt concentrations. Increasing salt concentrations negatively affected above-ground and below-ground parameters. However, SA and GA₃ treatments had positive impacts on all examined traits. SA and GA₃ priming treatments emerged as important strategies supporting root and shoot growth under saline conditions, thereby strengthening plant adaptation. The best results were obtained in groups exposed to 75 mM salt stress, where 300 mg/L GA3 was applied, and in groups without salt stress, where the same GA3 dose was applied. It was concluded that GA₃ priming treatments, in particular, were more effective than SA treatments, alleviating salt stress and positively contributing to plant development. Full article

Nitrogen is a critical nutrient that influences plant growth and resistance to pathogens; however, its impact on disease dynamics, particularly downy mildew infection, and the associated physiological responses in cucumber during early growth stages remains poorly understood. To evaluate the combined effects of downy mildew (caused by Pseudoperonospora cubensis) infection and nitrogen application on cucumber growth and physiological traits during the seedling and vine development stages, two downy mildew treatments— infected (B0) and non-infected(B1)—and three nitrogen levels—T1 (N-50%), T2 (N-100%), and T3 (N-150%)—were applied. Significant differences were observed between all treatments (p < 0.05). Among them, the B1T3 treatment had the most pronounced stimulatory effect, particularly on growth parameters (such as plant height, stem diameter, and leaf area). Without any disease infection (B1), the B1T2 treatment showed an increasing trend in photosynthetic rate and a more notable rise in stomatal conductance. In contrast, with downy mildew infection (B0), photosynthetic rates declined under B0T1 and B0T2. Moreover, with downy mildew infection (B0), the intracellular CO₂ concentration, stomatal conductance, and transpiration rate of cucumber leaves decreased in the B0T1, B0T2, and B0T3 treatments. Plant height, stem diameter, and leaf area responded variably to nitrogen levels and downy mildew infection. The total root length, root surface area, average root diameter, total root volume, and total root tips of cucumber plants were significantly different under different experimental conditions (p < 0.05). Consequently, this study provides a theoretical basis for stress-resistant cucumber cultivation in greenhouses and has practical implications for advancing the sustainable development of the greenhouse cucumber industry. Full article

Pearl millet is primarily grown under rainfed conditions in Sub-Saharan Africa. Early droughts are prevalent in the Sahel region, where pearl millet is widely cultivated, and they severely impact pearl millet growth and productivity by affecting plant stand and reducing plant density in the field. Consequently, genetic improvement for early drought tolerance is a promising strategy to enhance productivity in these regions. This study aims to identify pearl millet lines that are tolerant to water stress at the seedling stage by assessing various water-stress-tolerance traits. Two hundred pearl millet inbred lines were screened for drought tolerance by inducing water stress with polyethylene glycol 6000 (PEG 6000) in the laboratory. The experiment was repeated in the greenhouse using pot screening. The experimental design was an alpha lattice with 10 entries × 20 blocks in two replications. Four treatments (0 g/L, 115 g/L, 235 g/L, 289 g/L) were applied in the laboratory: one control and three concentrations of PEG 6000. Control and stress were applied in the greenhouse. Data were collected on germination rate and growth parameters, including root and seedling length, leaf length and width, and chlorophyll content. Results revealed significant differences among the pearl millet inbred lines under both drought and well-watered conditions. The inbred lines IP-16403 and IP-18062 were the most tolerant in both the greenhouse and laboratory. Water stress significantly reduced plant growth, although an increase in root length was observed in some lines. The number of days to 50% emergence was positively and strongly correlated with survival time (+0.45), while leaf width was negatively correlated with survival time (−0.29) and water stress tolerance (−0.37). The drought-tolerant and drought-susceptible pearl millet inbred lines identified in this study provide valuable genetic resources for enhancing pearl millet productivity in arid and semi-arid environments, especially in the face of unpredictable climate variability. Full article

Heavy metal pollutants and organic contaminants often co-exist in the environment, posing significant ecological risks due to their combined toxicity. Phytoremediation, a plant-based biotechnology, offers a promising solution for pollutant removal. This study investigated the potential cadmium (Cd) removal capacity of Narrow Crown Black-Cathay poplar (Populus × canadensis Moench × Populus simonii Carr. f. fastigiata Schneid.) under combined Cd-phenol stress. The results showed that the combined stress synergistically inhibited the photosynthetic physiological characteristics, with an inhibition rate up to 54.0%, significantly higher than that under single stress (p < 0.05). Cd accumulation varied markedly among plant organs, following the order: root (ranging from 4000.2 to 9277.0 mg/kg) > stems (ranging from 96.0 to 383.6 mg/kg) > leaf (ranging from 10.3 to 40.1 mg/kg). Phenol enhanced Cd absorption and enrichment in the roots by up to 1.8 times but reduced its translocation to aboveground parts by 37.8–40.0%. Notably, at low Cd concentrations, the Cd removal efficiency under combined stress (26.0%) was substantially higher than under single Cd stress (6.6%). In contrast, biomass, tolerance index, and root–shoot ratio were slightly affected in all treatments (p > 0.05). These findings demonstrate that Narrow Crown Black-Cathay poplar is a suitable candidate for the short-term remediation of Cd in environments co-contaminated with cadmium and phenol. Full article

The wide use of antibiotics in multiple fields leads to their entry into the environment, challenging agriculture and ecology and potentially affecting maize seedling growth. In this study, maize variety Longken 10 was chosen as the experimental material. Subsequently, two antibiotics commonly utilized in production, namely oxytetracycline (OTC) belonging to the tetracycline class and ciprofloxacin (CIP) from the quinolone class, were selected. To comprehensively examine the impacts of these antibiotics on the phenotype, photosynthetic enzymes, nitrogen metabolism, and endogenous hormone contents of maize seedlings, a series of different concentration gradients (0, 3, 5, 30, 60, and 120 mg·L⁻¹) were established, and the nutrient solution hydroponic method was employed. The results showed that, compared with the control group (CK), the activities of all indicators of maize seedlings were the strongest and the seedling growth was the most vigorous when the concentration of CIP was 5 mg·L⁻¹ and that of OTC was 3 mg·L⁻¹. The inhibitory effect of OTC on various indicators of maize seedlings was stronger than that of CIP. The underground parts of maize seedlings were more sensitive to OTC and CIP than the aboveground parts. Overall, maize seedlings exhibited a trend where high concentrations (30–120 mg·L⁻¹) of antibiotics inhibited growth, while low concentrations (3–5 mg·L⁻¹) promoted growth. The treatment groups with 3–5 mg·L⁻¹ of OTC and CIP increased maize seedling growth phenotypes, the robust growth of seedlings with enhanced vitality, and the relative water content of maize leaves; decreased the relative electrical conductivity of maize leaves, indicating reduced cell permeability; increased the activities of leaf photosynthetic enzymes (PEPCase, RUBPCase, PPDK, NADP-ME, and NADP-MDH); increased the levels of hormones (IAA, GA, and ZR) in maize leaves and roots; decreased the levels of ABA and MeJA; increased the levels of nitrogen metabolism-related enzymes (GS, GOGAT, and GAD) in roots and leaves; decreased the GDH level; enhanced root activity and increased various root parameters (including average diameter, number of root tips, total volume, total root length, and root surface area), indicating vigorous root growth. Compared with CK, the treatment groups with 30–120 mg·L⁻¹ of OTC and CIP reduced the phenotypes of maize seedlings, decreased the relative water content of maize leaves and increased the relative electrical conductivity of maize leaves, indicating enhanced cell permeability; reduced the activity of leaf photosynthetic enzymes, leading to weakened photosynthesis and decreased photosynthetic productivity; lowered the levels of IAA, GA, and ZR in leaves and roots of maize seedlings, and increased the levels of ABA and MeJA; decreased the levels of GS, GOGAT, and GAD in leaves and roots of maize seedlings, and increased the GDH level; reduced root activity, with the corresponding decrease in various root parameters. Full article

Golden thistle (Scolymus hispanicus L.) is a wild edible green of high nutritional value, used in the traditional Mediterranean diet. Nowadays, there is an increasing demand from consumers for golden thistle and concomitantly an increasing interest in integrating it into modern cultivation systems. Soilless culture is a promising cultivation option that can maximize yield and quality of golden thistle. The aim of this study was to examine the combined effect of electrical conductivity (EC) and nitrogen (N) supply level on growth and nutritional quality of golden thistle grown on a substrate in a soilless cropping system. The two experimental factors were examined in a 2-factorial experiment with two EC levels, a low (2.2 dS m⁻¹) and high (2.8 dS m⁻¹), combined with two total-N (NO₃⁻ + NH₄⁺) supply levels, low (13.30 mmol L⁻¹) and high (17.30 mmoL L⁻¹), in the supplied nutrient solution. Root fresh and dry weight (commercial yield) were unaffected by treatments; however, high EC significantly reduced shoot fresh and dry biomass by 21 and 28% compared to low EC. High EC increased K⁺ concentrations in shoots and roots but decreased shoot Ca²⁺ level. Nitrate concentration in the drainage solution and plant tissues was primarily driven by N supply, with high N increasing leaf NO₃⁻ by up to 45% without surpassing the regulatory safety limit. Water productivity did not differ among treatments, but low EC improved agronomic efficiency of K⁺, Ca²⁺, Mg²⁺, and S, while low N enhanced N agronomic efficiency by 44%. Overall, low EC promoted vegetative growth and nutrient use efficiency, while increasing N above 13.3 mmol L⁻¹ offered no yield benefit and raised tissue nitrate levels. For optimal yield and quality, a nutrient solution with low EC and N supply is recommended for the soilless cultivation of golden thistle. Full article

Alkanna tinctoria (L.) Tausch is a valuable medicinal plant known for its root-derived hydroxynaphthoquinone enantiomers, alkannin/shikonin (A/S), which exhibit significant pharmaceutical and cosmeceutical potential. However, its limited natural distribution and overharvesting pose conservation challenges, necessitating sustainable cultivation and extraction strategies. The application of Natural Deep Eutectic Solvents (NaDESs) has garnered significant attention as sustainable alternatives to conventional solvents. However, their toxicity in living plant systems remains largely unexplored. This study presents the successful establishment of an ex situ hydroponic cultivation system using the nutrient film technique (NFT) to grow A. tinctoria under greenhouse conditions. The system promoted plant acclimatization, vigorous root development, and initial production of A/S derivatives. In parallel, the toxicity evaluation of a bio-based NaDES, LeG_5_20 (levulinic acid–glucose, 5:1, with 20% water), applied as a circulating medium, was assessed. Physiological stress responses of the plants to NaDES circulation were assessed through non-destructive measurements, including stomatal resistance, photosynthetic and transpiration rates, and sub-stomatal CO₂ concentration. Short-term (24 min) exposure to NaDES showed no significant adverse effects, while longer exposures (4–8 h) induced marked stress symptoms and loss of leaf area. These findings demonstrate the feasibility of integrating green hydroponic systems with eco-friendly extraction solvents and provide a framework for further optimization of plant age, solvent exposure time, and system design to enable sustainable metabolite recovery without plant destruction. Full article

Excessive concentrations of nickel (Ni) are phytotoxic, leading to disturbances in plant cell structure and function. Although some attempts have been made to elucidate the Ni impact on plant metabolism, the effect of this metal on nitrogen assimilation and transformation of nitrogen compounds still remains poorly understood. The objective of our study was to gain a better insight into the Ni influence on nitrogen metabolism in cucumber plants. Nitrogen metabolism-related enzyme activities and selected metabolite contents were assayed using spectrophotometric methods. Additionally, in the leaves, nitrogen assimilation-involved gene expression was analyzed using quantitative real-time PCR. Nickel treatment resulted in a decline in ${\mathrm{NO}}_3^{-}$ content in the leaf and ${\mathrm{NH}}_4^{+}$ content in the root. In the leaf, ferredoxin-dependent glutamate synthase (Fd-GOGAT) activity decreased, while NADH-dependent glutamate synthase (NADH-GOGAT) and glutamate dehydrogenase (GDH) activities increased. The GDH activity showed increases in both its aminating (NADH-GDH) and deaminating (NAD-GDH) functions. The activities of the other enzymes involved in nitrogen assimilation were not influenced by Ni stress. In the root, the activities of most enzymes were downregulated by Ni treatment except for NADH-GDH and NAD-GDH activities which showed increases. While glutamate content remained unaltered after Ni exposure in the leaf, in the root it was slightly lowered. In contrast to the leaf, showing accumulation of non-protein thiols and proline, in the root, these compound contents were markedly decreased. Our study revealed an organ-specific response of cucumber plants to Ni treatment. Accumulation of glutamate derivatives involved in response to heavy metal stress without significant changes in glutamate content may suggest that in the leaf, the induction of NADH-GOGAT and NADH-GDH activities efficiently compensates for the reduced Fd-GOGAT activity. Additionally, the increased NADP-ICDH activity may support glutamate production by providing 2-oxoglutarate for reactions catalyzed by NADH-GOGAT and NADH-GDH. Full article

This study aimed to elucidate the physiological, biochemical, and transcriptional regulatory responses of potato plants to iron deficiency stress. Two potato varieties were selected for analysis: 05P (high tuber iron content) and CI5 (low tuber iron content). Tissue culture seedlings of both varieties were subjected to iron deficiency, and the effects on stem length, root length, fresh weight, soluble sugar and protein contents, as well as the activities of superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), and leaf chlorophyll content (SPAD) values were evaluated. Additionally, the impact of iron deficiency on zinc (Zn), magnesium (Mg), calcium (Ca), manganese (Mn), and copper (Cu) concentrations in different tissues were analyzed. Transcriptomic sequencing and quantitative real-time PCR (qRT-PCR) were performed on various seedling tissues. The results showed that iron deficiency significantly inhibited seedling growth and development, resulting in reduced plant height and fresh weight, increased root length, decreased leaf SPAD content, and elevated soluble sugar and protein concentration. SOD, POD, and MDA activities were also significantly increased. Elemental analysis revealed that iron deficiency enhanced the uptake and accumulation of Zn, Mg, Ca, Mn, and Cu across different tissues. Transcriptomic analysis identified differentially expressed genes (DEGs) significantly enriched in pathways related to photosynthesis, carbon metabolism, and ribosome function in roots, stems, and leaves. Iron deficiency induced the upregulation of H⁺-ATPase genes in roots (PGSC0003DMG400004101, PGSC0003DMG400033034), acidifying the rhizosphere to increase active iron availability. Subsequently, this was followed by the upregulation of FRO genes (PGSC0003DMG400000184, PGSC0003DMG400010125, PGSC0003DMG401009494, PGSC0003DMG401018223), which reduce Fe³⁺ to Fe²⁺, and activation of IRT genes, facilitating Fe²⁺ transport to various tissues. Iron deficiency also reduced SPAD content in leaves, negatively impacting photosynthesis and overall plant growth. In response, the osmotic regulation and antioxidant defense systems were activated, enabling the plant to mitigate iron deficiency stress. Additionally, the absorption and accumulation of other metal ions were enhanced, likely as a compensatory mechanism for iron scarcity. At the transcriptional level, iron deficiency induced the expression of genes involved in metal absorption and transport, as well as those related to photosynthesis, carbon metabolism, and ribosomal function, thereby supporting iron homeostasis and maintaining metabolic balance under stress conditions. Full article

Nowadays, the use of natural biological bio-stimulants such as seaweed extract (SWE) is highly considered for alleviating the adverse effects of drought stress in many plant species. This study evaluated the effects of drought stress and foliar application of seaweed extract (SWE) on the morphological, physiological, and phytochemical traits of Pelargonium graveolens. Three levels of water irrigation regimes were used in combination with four SWE concentrations (0, 2.5, 5, and 7.5 mL L⁻¹). Based on the GC-MS analysis, 83 compounds were identified, of which citronellol, citronellyl formate, α-gurjunene, δ-cadinene, and γ-cadinene were the major constituents of P. graveolens leaves. The highest citronellol content (56.2%) was found under moderate irrigation with 5 mL of L⁻¹ SWE, while the lowest amount (26.78%) was obtained under full irrigation with no foliar application of SWE. Citronellyl formate and α-gurjunene exhibited their highest relative abundance under non-stress conditions following foliar application of 5 mL L⁻¹ and 0 mL L⁻¹ of SWE, respectively. In contrast, δ-cadinene reached its highest value under severe drought stress when treated with 7.5 mL of L⁻¹ SWE, indicating a stress-responsive shift in essential oil (EO) composition profile. Principal component analysis (PCA) revealed that full irrigation with 7.5 mL of L⁻¹ SWE and mild drought with 5 mL of L⁻¹ SWE were the best treatments for ameliorating the EO content and composition. ANOVA revealed that SWE significantly improved the fresh root weight, leaf dimensions, carotenoids, total chlorophyll, protein content, and antioxidant enzyme activities. The 7.5 mL of L⁻¹ SWE treatment notably increased fresh root weight by 29.16% and enhanced chlorophyll and protein levels under moderate and severe drought conditions. Drought stress reduced shoot biomass but had no significant effect on chlorophyll content. Carotenoid and antioxidant activities were significantly influenced by both drought and SWE, with the highest levels observed at 5 mL of L⁻¹ SWE. Antioxidant enzymes (CAT, SOD, and guaiacol peroxidase) and total antioxidant activity were enhanced by SWE and its interaction with drought stress conditions. These results suggest that foliar SWE application at 5–7.5 mL L⁻¹ effectively mitigates drought stress and enhances both growth and EO composition in P. graveolens. Full article

Climate change and soil salinization threaten crop productivity, particularly affecting salt-sensitive species like hemp (Cannabis sativa L.), which is gaining importance in sustainable agriculture and bioeconomy. Jasmonates (JAs) offer promising potential for enhancing plant abiotic stress tolerance. Given hemp’s inherently low salt tolerance and limited data on JAs-mediated responses, we investigated salinity tolerance JAs modulation using methyl jasmonate (MeJA; 0.001–0.01 mM) and the JAs-biosynthesis inhibitor mefenamic acid (MEF; 0.01–0.1 mM) applied via seed priming or foliar treatment in factorial experiments with NaCl concentrations of 0.05–0.3 M. We demonstrate that MeJA and MEF differentially modulate responses of Henola hemp variety to salt stress during germination and seedling development. At 0.1 M NaCl, 0.01 mM MeJA enhanced germination rate by 25% compared to the salt-only control, indicating a protective effect on initial development, whereas 0.1 mM MEF exacerbated salt toxicity by increasing seed damage and reducing respiration by 57%, subsequently suppressing seedling growth. In 25-day-old seedlings exposed to 0.3 M NaCl, 0.001 mM MeJA treatment increased root length by 30 mm, fresh biomass by 50%, chlorophyll content by 20%, and photosynthetic efficiency by 23%, while reducing water deficit by 60% and leaf injury by 40%. MEF co-treatment partially reversed these protective effects, reducing MeJA-mediated improvements, confirming that maintaining JAs homeostasis is critical for salt-stress adaptation. These findings establish MeJA as a promising tool for enhancing hemp cultivation under saline conditions and provide a framework for integrating JAs treatments into sustainable hemp cultivation protocols. Full article

Primula veris L. (cowslip) is a medicinal plant traditionally used for respiratory ailments, with its therapeutic properties attributed to triterpene saponins and phenolic glycosides found in the roots and the aerial parts. The present study aimed to investigate the impact of different LED light spectra (red, blue, red:blue, and white fluorescent as a control) on P. veris’s relative growth rate, physiology, and secondary metabolite production to optimize its cultivation under controlled conditions. The results demonstrate that the light quality significantly influences P. veris’s growth characteristics, physiology, and secondary metabolite production. Red light promoted leaf expansion, while the red:blue LED combination enhanced the root fresh weight and concentration of total chlorophylls and carotenoids in primrose leaves in comparison to the white fluorescent and solitary red light, respectively. Red light significantly increased the accumulation of key secondary metabolites (primeverin, primulaverin, and primulic acids) in roots during the flowering phase compared with the white inflorescent. In addition, the concentration of phenolic compounds was strongly influenced, showing a decrease between the vegetative and the flowering stage of development. Finally, this study highlights the potential of tailored LED lighting to optimize P. veris cultivation, enhancing both biomass and the production of valuable bioactive compounds, taking into account the developmental stage of the plants. Full article