Search Results (290)

Crocosmia is a genus of bulbous, perennial plants from the Iridaceae family whose characteristic red to orange pigmentation suggests the presence of anthocyanins, flavonoids, and carotenoids—secondary metabolites often associated with antioxidant activity. This study aimed to characterize and compare the major pigment-related metabolites in two Crocosmia varieties (Crocosmia masoniorum “Lucifer” and Crocosmia aurea) through chromatographic (HPLC-DAD) and spectrophotometric analyses (UV-Vis), using Crocus sativus L. flowers as a reference matrix. Successfully, the major crocin trans-4-GG, the flavonol kaempferol-3-O-β-sophoroside, and the anthocyanin delphinidin-3-O-β-glucoside were quantified in Crocosmia flowers. Additional metabolites absent in Crocus sativus L. were also identified and quantified. Both Crocosmia varieties exhibited higher antioxidant capacity than Crocus sativus L. flowers, highlighting their potential for future applications in pharmaceutical, nutraceutical, or functional ingredient development. Full article

The cryptochromes (CRYs) perceive blue light to regulate various developmental and metabolic events. However, the role of CRYs in flavonoid biosynthesis and flower pigmentation in safflower (Carthamus tinctorius L.) remains unknown. In this study, we determined flower color diversity among 485 safflower genotypes using the integrated CIELAB color space parameters and cluster analysis. On this basis, distinct colors were categorized into four groups, namely white (WW), yellow (YY), orange–red (OR), and yellow–red (YR). A genome-wide association study (GWAS) via 933,444 high-quality SNPs showed CtCRY2 as a flower color variation gene. Subsequently, genomic analysis identified three genes of the CRY family, including CtCRY1.1, CtCRY1.2, and CtCRY2. In silico analysis, such as gene structure, phylogeny and cis-acting elements, suggested CtCRY1.1 as a key candidate in pigment biosynthesis and was, therefore, selected for functional validation. Overexpression of CtCRY1.1 in Arabidopsis accumulated a high flavonoid content, particularly upregulating the expression of CHS, FLS, and ANS, proving its role as a positive regulator of flavonoid biosynthesis in safflower. These findings provide insights into the molecular mechanisms underlying flower color regulation in safflower and highlight CtCRY1.1 as a new target to enhance pigment-related traits in plants. Full article

This article presents a comprehensive analysis of the polychrome paintings on the Flower Peking Opera Theatre in Bozhou, Anhui Province, China. A multi-technique approach was employed, including polarized light microscopy (PLM), X-ray fluorescence (XRF), micro-Raman spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy with energy-dispersive spectrometry (SEM-EDS), and Herzberg staining to determine the composition and methodologies involved in the formation of the pigment layer, the white primer, and the ground layer. The analysis identified cinnabar (red), both artificial ultramarine and Prussian blue (blue), a mixture of barite and gypsum (white), a mixture of chromite and Prussian blue (green), and carbon black (black) in the pigment layer. The ground layer was found to consist of clay and plant fibers (cotton and hemp), while the white prime layer was primarily composed of barite and gypsum. This research provides insights for future conservation and restoration efforts. Full article

Gloriosa superba ‘Passion Flame’ (flame lily) is a distinctive ornamental plant characterized by its striking floral structure and vivid coloration. During flower development, flame lily tepals undergo a pronounced color transition from green at the bud stage to bright red with a yellow base at maturity, providing an excellent system for studying flower pigmentation in monocots. Here, we applied a multi-omics approach to examine metabolite accumulation and gene expression dynamics across four stages of flower development. Metabolomic profiling identified 240 flavonoids and four anthocyanins, among which pelargonidin-3-O-glucoside showed the highest relative abundance among red pigmentation. Transcriptome analysis revealed that seven key anthocyanin structural genes showed strong correlations with anthocyanin accumulation. In parallel, several chlorophyll degradation genes, including GsSGR and GsPPH, were upregulated during tepal maturation, suggesting transcriptional activation of chlorophyll degradation pathways concurrent with pigment accumulation. Co-expression network analysis further identified GsMYB75 and GsMYB114 as temporally distinct regulators associated with anthocyanin biosynthesis, acting together with bHLH, NAC, and AP2/ERF transcription factors. This study provides new insights into the pigment regulation in G. superba ‘Passion Flame’ and offers candidate regulatory components for future functional studies and the improvement of ornamental traits in monocotyledonous plants. Full article

Hyperspectral imaging (HSI) is a noncontact camera-based technique that enables deep learning models to learn various plant conditions by detecting light reflectance under illumination. In this study, we investigated the effects of four light sources—halogen (HAL), incandescent (INC), fluorescent (FLU), and light-emitting diodes (LED)—on the quality of spectral images and the vase life (VL) of cut roses, which are vulnerable to abiotic stresses. Cut roses ‘All For Love’ and ‘White Beauty’ were used to compare cultivar-specific visible reflectance characteristics associated with contrasting petal pigmentation. HSI was performed at four time points, yielding 640 images per light source from 40 cut roses. The results revealed that the light source strongly affected both the image quality (mAP@0.5 60–80%) and VL (0–3 d) of cut roses. The HAL lamp produced high-quality spectral images across wavelengths (WL) ranging from 480 to 900 nm and yielded the highest object detection performance (ODP), reaching mAP@0.5 of 85% in ‘All For Love’ and 83% in ‘White Beauty’ with the YOLOv11x models. However, it increased petal temperature by 2.7–3 °C, thereby stimulating leaf transpiration and consequently shortening the VL of the flowers by 1–2.5 d. In contrast, INC produced unclear images with low spectral signals throughout the WL and consequently resulted in lower ODP, with mAP@0.5 of 74% and 69% in ‘All For Love’ and ‘White Beauty’, respectively. The INC only slightly increased petal temperature (1.2–1.3 °C) and shortened the VL by 1 d in the both cultivars. Although FLU and LED had only minor effects on petal temperature and VL, these illuminations generated transient spectral peaks in the WL range of 480–620 nm, resulting in decreased ODP (mAP@0.5 60–75%). Our results revealed that HAL provided reliable, high-quality spectral image data and high object detection accuracy, but simultaneously had negative effects on flower quality. Our findings suggest an alternative two-phase approach for illumination applications that uses HAL during the initial exploration of spectra corresponding to specific symptoms of interest, followed by LED for routine plant monitoring. Optimizing illumination in HSI will improve the accuracy of deep learning-based prediction and thereby contribute to the development of an automated quality sorting system that is urgently required in the cut flower industry. Full article

The corolla of Rehmannia glutinosa typically exhibits a stable reddish-purple color, but a naturally occurring yellow-flowered variant has recently been identified. To clarify the molecular basis of flower color variant, metabolomics, transcriptomics, and variant analyses were integrated. Metabolomic profiling revealed that the yellow phenotype was associated with lower anthocyanin levels and higher carotenoid levels. Specifically, the decreased cyanidin-3-O-glucoside led to a loss of red, while increased lutein provided the basis for the yellow color. Transcriptomic analysis revealed a downregulation of anthocyanin biosynthetic genes, including CHS, CHI, F3H, DFR, and ANS, in the yellow-flowered variant, and three S6-subgroup R2R3-MYB genes, including the known anthocyanin activator RgMYB41 (gene-DH2020_015992), were downregulated. Variant analysis showed that A12S and G255E in the gene-DH2020_015992 transcription factor were predicted to markedly alter protein conformation and potentially impair regulatory function. Subcellular localization and transcriptional activation assays further supported the functional characterization of gene-DH2020_015992 as a transcription factor. Collectively, these findings suggest that flower color variation in R. glutinosa is driven by MYB-mediated repression of anthocyanin biosynthesis and by carotenoid accumulation. This study provides a comprehensive genetic explanation for flower color variation in R. glutinosa and offers a theoretical foundation for floral pigmentation in plants. Full article

Berry color is a critical determinant of grape quality and market value. While the genetic basis of skin color has been extensively studied, the regulatory network controlling flesh coloration remains largely uncharacterized. To systematically dissect the independent genetic architectures underlying these traits, we performed a genome-wide association study (GWAS) on 130 grape accessions, integrated with spatiotemporal expression profiling, subcellular localization, and functional validation. Our analysis revealed distinct genetic loci for skin and flesh color, confirming their independent regulation. For skin color, GWAS robustly validated VvMYBA2 as a major locus, explaining up to 51.5% of the phenotypic variance. More importantly, for flesh color, we identified and prioritized VvF3′M (Flavonoid 3′-monooxygenase) as a key candidate gene. Heterologous overexpression of VvF3′M in tobacco resulted in a profound 13.5-fold increase in anthocyanin content, suggesting its potential role as a rate-limiting enzyme in flesh pigmentation. Intriguingly, VvF3′M-overexpressing plants also exhibited a significant increase in flower number, suggesting a novel role beyond pigment biosynthesis. This study provides a comprehensive genetic and functional framework for understanding berry coloration, identifies VvF3′M as a prime target for breeding red-fleshed grapes, and reveals unexpected crosstalk between color metabolism and reproductive development. Full article

Ptelea trifoliata L. is a perennial plant of the Rutaceae family and contains secondary metabolites with potential biological relevance. Due to limited information on its activity, the objective of this study was to evaluate the biological properties of its flower extracts and to determine their phytochemical composition. Flowers were dried and subjected to ultrasound-assisted extraction using methanol, 60% methanol and water. LC–MS/MS was used for qualitative profiling, HPLC for quantitative determination, and spectrophotometry for measuring total phenolic and flavonoid content. The antioxidative capacity of the extracts was determined using DPPH, CUPRAC, FRAP, and iron chelation assays. Enzymatic inhibition analyses were performed for hyaluronidase, indicative of anti-inflammatory properties, and tyrosinase, associated with pigmentation mechanisms. The wound-healing capacity was evaluated in vitro using a scratch assay. Our research revealed the highest levels of polyphenols in the 60% methanol extract and of flavonoids in the methanol extract. The occurrence of chlorogenic acid, rutin, hyperoside, and astragalin was also demonstrated. Both methanol and 60% methanol extracts demonstrated antioxidant effects. The methanol extract showed the greatest hyaluronidase inhibition, while the 60% methanol extract was the most effective in suppressing tyrosinase activity and promoting wound closure. Principal component analysis showed that the contents of polyphenols or flavonoids were associated with enzyme-inhibitory or antioxidant activities. Moreover, the 60% methanol and water extracts exhibited notable wound healing properties. These results highlight the antioxidant, enzyme-modulating and regenerative potential of P. trifoliata flower extracts, suggesting their possible use in biomedical and dermatological applications. Full article

Natural dyes have emerged as a promising alternative to synthetic dyes for industrial applications due to their advantages, namely, easy availability, low cost, and environmental friendliness. In this sense, natural dyes, due to their potential to react over the pH range, could offer an alternative to conventional pH measuring techniques for industrial products, such as potentiometers, sensors, or indicator drops. Therefore, this project aims to evaluate the potential of several natural organic dyes in response to changes in pH and develop an indicator for determining pH grades. We extracted and analyzed the pigments of forty natural vegetable species using two extraction methods with a mixture of solvents, specifically 70% MeOH/30% H₂O. The results find that pigments of cabbage, hibiscus flower, radish, and turmeric in their dry state exhibit the best reaction over a broad pH range, and color can be easily distinguished according to its level. These findings demonstrate the potential of natural dyes as a novel approach for pH verification, providing a sustainable and cost-effective alternative to conventional techniques. Full article

Marigold (Tagetes erecta) is an important ornamental and industrial crop valued for its high lutein content. Although petal pigmentation during inflorescence development involves coordinated chlorophyll degradation and carotenoid biosynthesis, the transcriptional mechanisms regulating these processes remain poorly understood. Here, we identified a MADS-box transcription factor, TeMADS6, that coordinately regulates chlorophyll and carotenoid metabolism in marigold. Constitutive overexpression of TeMADS6 resulted in yellow-green petals. HPLC analysis revealed that lycopene, antheraxanthin, violaxanthin, zeaxanthin, and lutein levels were substantially reduced in TeMADS6-overexpression lines, while chlorophyll content was significantly increased compared with wild-type plants. Transcriptome profiling revealed strong repressions of the carotenoid biosynthetic genes TePSY1 and TeHYDB in transgenic florets. Moreover, the chlorophyll degradation gene TeNYC1 and TePPH2 were significantly downregulated, whereas TeSGR2 was upregulated. Together, these findings demonstrate that TeMADS6 acts as a dual-function transcriptional regulator controlling both chlorophyll degradation and carotenoid biosynthesis. This study provides new genetic resources for manipulating petal color and enhancing lutein accumulation in marigold, and advance understanding of the transcriptional networks orchestrating pigment metabolism during flower development. Full article

Gastrodia elata Blume is a well-known traditional Chinese medicine. The color of flower and flower stalk are important characteristics in the classification of G. elata. However, the mechanisms of pigment formation in different types of G. elata are not yet elucidated. To understand this, targeted metabolomics as well as transcriptomics analyses were carried out in this study. The differential accumulation and the typical components of pigments in different types of G. elata were elucidated. According to our research, the accumulation of carotenoids rather than anthocyanins likely contributes to the pigment content in G. elata. The different accumulations of carotenoids including violaxanthin, lycopene, α-carotene, and α-cryptoxanthin are the main reasons that contribute to the color differences in the flowers and flower stalks of these three G. elata varieties. Integrated multi-omics analysis enriched 50 and 17 differential genes in the flavonoid–anthocyanin and carotenoid biosynthesis pathways, respectively. Among these, PSY, PDS, CCD, UGT, and ANR were identified as critical genes responsible for the differential pigment accumulation in G. elata varieties, while the MYB TFs were tightly associated with main genes expression and content of carotenoids. Overall, this study enhances the current understanding of pigments’ metabolites profiles and contributes valuable insights into the molecular mechanisms underlying G. elata carotenoid biosynthesis; these findings also provide valuable guidance for future carotenoid biofortification and molecular breeding in G. elata. Full article

The orange mullein is a biennial plant whose tall yellow flower spikes contain mucilage, saponins, and other medicinal compounds that have a beneficial effect on respiratory problems. As light quality is known to influence plant morphology and physiology, with effects often depending on the species, understanding these responses in mullein is of particular interest. Therefore, this study aimed to investigate the combined effects of different light-emitting diodes (white, red and blue) and their corresponding photon flux densities (PPFD) on the morphology, pigment composition, antioxidant activity, fluorescence parameters and OJIP transient curves in mullein (Verbascum phlomoides L.) seedlings. Seedlings grown under blue light, which had relatively higher PPFD, showed the greatest root length, leaf number, leaf and root fresh and dry biomass. Red light, with lower PPFD, resulted in the lowest values for these parameters. Compared to white light, pigment analysis showed that blue light increased chlorophyll a, total chlorophyll, carotenoid content, and the Chl a/b ratio. Also, blue light enhanced antioxidant activity, as well as the accumulation of phenolic compounds and flavonoids, indicating that it appeared to enhance the synthesis of secondary metabolites under this spectrum. In contrast, seedlings under red light exhibited the lowest ferric reducing antioxidant power values and tended to reduce levels of phenols and flavonoids, indicating a weaker antioxidative response. It was found that white light appeared to enhance the photochemical activity of photosystem II (PSII) and energy dissipation. Blue light improved linear electron transport, photosystem I (PSI) activity and overall photosynthetic performance. Red light preferentially increased electron flow towards the final acceptors of PSI, affecting the terminal part of the electron transport chain. Analysis of OJIP curves revealed spectrum and intensity-specific changes in the L, K, H, and G bands, demonstrating that light treatments with differing PPFDs selectively modulate PSII and PSI function. Full article

Rice is a staple food grown worldwide. While white rice varieties have been extensively studied, there is limited information on the performance of pigmented rice genotypes and their tolerance to water deficit. This study evaluated nineteen black rice genotypes and one white cultivar over three years under contrasting water regimes: traditional flooding and non-flood irrigation (NFI). Genotype–environment interactions and their impact on agronomic, yield, and grain quality traits were assessed. Black genotypes under NFI showed reduced flowering and grain quality. The average yield was 31% lower than the white cultivar. Significant genetic correlations were found between grain yield and days to anthesis (DSA), grain weight (TGW), chalkiness (CHA), and translucency (TRAN), with high broad-sense heritability (H² > 0.9). Most traits exhibited high heritability (H² > 0.7), indicating strong genetic stability. Grain yield (GR) was highly and negatively correlated with percent sterility (PS) (r = −0.84) and had a heritability of 0.76. Environmental conditions significantly influenced yield, confirming the potential for selecting water stress–tolerant genotypes. These findings provide valuable insights into black rice breeding and optimizing water management practices to support sustainable production. To our knowledge, this study is the first to evaluate the performance of a diverse set of black rice genotypes across multiple seasons under contrasting water regimes in a Mediterranean environment. Full article

[Background] Marigold (Tagetes erecta L.) is the main source of the natural pigment lutein. [Methods] In this study, Marigold served as the experimental material for systematic observation of floral organ development. Based on floral morphology and lutein content, the full-flowering stage was identified as the optimal harvesting period. [Results] Under different light intensity gradients (30–1500 μmol·m⁻²·s⁻¹), the highest lutein content in petals occurred at ≈500 μmol·m⁻²·s⁻¹. Increased light intensities promoted flowering and enlarged flower diameter while significantly shortening the growth cycle. Transcriptome analysis revealed that light intensity variation markedly influenced the expression of genes related to metabolic pathways, plant hormone signal transduction, and carotenoid biosynthesis, and enriched transcription factor families including bHLH, MYB, NAC, and WRKY. Metabolomic profiling identified lutein esters, such as lutein dimyristate and lutein dipalmitate, as the dominant accumulated forms, with their contents positively correlated with light intensity; under high light, intermediate metabolites, including α-cryptoxanthin and zeaxanthin, were significantly up-regulated. [Conclusions] This study clarifies the molecular mechanism by which light intensity precisely regulates lutein accumulation through coordinated synthesis, esterification, and degradation pathways, offering a theoretical foundation for light-regulated cultivation of T. erecta L. and efficient lutein production. Full article

Drought stress during the reproductive phase substantially reduces seed yield and quality, posing a major challenge to sustainable crop production under climate change. This study investigated the effects of drought stress at the flowering stage on selected biochemical and physiological parameters in 18 carrot accessions. To describe the long-term consequences of drought comprehensively, we examined seed quality parameters. Our analyses revealed that stress responses are highly dependent on the genotype and the parameter examined. Regarding antioxidant responses and potential tissue damage caused by drought, ‘Dolanka’, DC97, DC265, DC359, DC522, DC701, DC704, and DC720 exhibited the highest tolerance. The photosynthetic apparatus and pigments were maintained under stress in DC233, DC522, DC717, and DC728. Germination parameters served as reliable indicators of stress tolerance in DC97, DC359, DC432, DC522, DC701, and DC722 accessions. Based on these findings and detailed discussion of the results, we conclude that tolerance/sensitivity assessment of carrot genotypes should consider the holistic response of the plant rather than individual parameters. Through overall assessment, we recommended DC522 accession as the most drought-tolerant, given its enhanced ROS (Reactive Oxygen Species) scavenging mechanisms, increased chloroplast pigments accumulation, and superior germination parameters under drought conditions. Conversely, DC295 should not be cultivated under water-deficient conditions due to its impaired ability to detoxify ROS, altered photosynthetic activity, and disrupted seed germination under such conditions. These results collectively highlight the potential for selecting drought-tolerant carrot genotypes in breeding programs targeting improved seed performance under water-limited conditions, thereby supporting the development of resilient cultivars adapted to future climate challenges. Full article