Petal Color Research Articles

Genetic diversity of local sweet potato cultivars (Ipomoea batatas [L.] Lam.) from Bulungan, North Kalimantan based on morphological characters

Indonesia is one of the centers of sweet potato diversity worldwide. Sweet potatoes have the potential to be developed for food consumption. This research aims to determine the diversity of sweet potato cultivars, their morphological characteristics, and the relationships between local sweet potato cultivars in Bulungan Regency, North Kalimantan. The local sweet potato cultivars were selected using purposive sampling with the exploration method. The morphological characterization of the samples is based on IBPGR (International Board for Plant Genetic Resources) standards. Cluster analysis was conducted to identify the relationships using MVSP software version 3.1. The research identified 27 local sweet potato cultivars in Bulungan Regency. Morphological characterization revealed 41 characters that can differentiate each local sweet potato cultivar. The most influential characteristics include leaf shape, flower surface texture, the position of the stigma, flower surface color, back petal color, center shape and the number of lobes, primary leaf vein color, lobe type, main leaf bone color, stem internode length, and plant type. A flower shape that had not been discovered before, a pentagonal shape with curves, was identified. Cluster analysis divided the cultivars into two major groups with a coefficient range of 0.593 to 0.888 (59.3 to 88.8%). Cluster A consisted of one member, LK-7 (purple sweet potato), while Cluster B consisted of several subgroups with 26 local cultivars. The people of Bulungan Regency use these local cultivars for food, animal feed, and medicinal purposes.

Comparative Study on Pigment Components (Flavonols and Anthocyanins) and Antioxidant Capacity in Different Colored Double-petal Lotus

Lotus, an edible flower with high ornamental values, takes forms in many sizes, shapes, and colors. Among which, double-petal lotus not only has higher ornamental values but also gives a yield advantage in exploitation due to the large number of petals. Flower color is an important ornamental indicator, and flavonoids are the key basis for color presentation as well as important active components in lotus. This research used petals of four different colored double-petal lotus cultivars to identify their petal color, pigment localization, and pigment components (flavonols and anthocyanins), as well as the antioxidant activity of the petal extraction solution using the ABTS method. It was discovered that the white YMQ was the brightest but had the lowest Chroma and the third-highest Hue angle, while the dark red WFMH was the darkest but had both the highest Chroma and Hue angle. Most of the colored pigments were located in all the thin-walled cells immediately adjacent to both the upper and lower epidermis. The yellow MLQS had the highest amount of Quercetin derivatives in flavonols but the lowest antioxidant activity, the dark red WFMH had the highest amount of anthocyanin, and the pink MDZ had the highest antioxidant activity. This research offers insights into the potential medical usage of certain double-petal lotus cultivars like MLQS and WFMH, hopefully providing a reference for the identification of raw materials for extracting pigments to improve sleep patterns and prevent Alzheimer’s Disease.

Active Modified Atmosphere Packaging Helps Preserve Quality of Edible Flowers

Edible flowers are becoming increasingly popular as food products, since they give aroma, color, and visual appeal and are also health-promoting compounds. However, they are a highly perishable product, thus post-harvest technologies are needed to extend their marketability. In this study, active (N2: 100%) and passive modified atmosphere packaging (MAP) technologies were applied to three edible flower species, namely Begonia grandiflora ‘Viking’, Tropaeolum majus, and Viola cornuta, stored at 4 °C. Even if the flowers’ quality decay occurred differently according to the species, active MAP better maintained petal colors and slowed down the edible flowers’ decay than passive MAP by decreasing flower respiration in all three species and sugars consumption in begonia; there was weight loss in nasturtium, and better preserved total phenolic content in begonia and viola. Coupling cold storage with active MAP can be an effective method to extend edible flowers’ post-harvest life.

Bcwf regulates the white petal color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis]

Flower color is important in determining the ornamental value of Brassica species. However, our knowledge about the regulation of flower color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis] is limited. In this study, we investigated the molecular mechanism underlying white flower traits in pak choi by analyzing a genetic population with white and yellow flowers. Our genetic analysis revealed that the white trait is controlled by a single recessive gene called Bcwf. Through BSA-Seq and fine mapping, we identified a candidate gene, BraC02g039450.1, which is similar to Arabidopsis AtPES2 involved in carotenoid ester synthesis. Sequence analysis showed some mutations in the promoter region of Bcwf in white flowers. Tobacco transient assay confirmed that these mutations reduce the promoter's activity, leading to downregulation of Bcwf expression in white flowers. Furthermore, the silencing of Bcwf in pak choi resulted in lighter petal color and reduced carotenoid content. These findings provide new insights into the molecular regulation of white flower traits in pak choi and highlight the importance of Bcwf in petal coloring and carotenoid accumulation.

A field investigation into potential reproductive and resistance advantages of purple-petalled plants in polymorphic populations of horsenettle (Solanum carolinense)

Background and aims – Variation in flower color among individuals within plant populations has long fascinated horticulturalists and evolutionary biologists alike. Nevertheless, the diversity of genetic factors and ecological interactions that act to maintain flower-color polymorphisms over time are understood for very few species. Here, we suggest that Solanum carolinense (horsenettle) makes an excellent model system for studying the evolutionary ecology of a flower-color polymorphism, and we begin to shed insight into factors that might affect the stability of the polymorphism. Material and methods – We transplanted 24 horsenettle ramets of each of 40 field-collected genets (10 genets per each of four source fields) into a common-garden plot (in an oldfield with an existing horsenettle population). For each ramet, we visually characterized petal color and quantified production of flowers, fruits, seeds, and damage by 11 species of herbivores. Key results – Rather than varying continuously within ramets and among genets, petal color fell into three relatively discrete categories that are common in most horsenettle populations: purple, white, and mauve. In the common-garden experiment, purple-petalled morphs initiated significantly more flower buds, opened more flowers, and produced more fruits and seeds than did the mauve-petalled or white-petalled morphs. Petal-color morphs differed only slightly in resistance to a minority of the herbivore community, with no consistent advantage for color morphs across species of herbivores or types of tissues fed upon. Conclusion – Horsenettle has numerous characteristics that make it an excellent system for studying the genetics and ecology that drive the maintenance of flower-color polymorphisms. Although pleiotropic effects of flower-color on resistance to herbivory appear to be minimal in horsenettle, potential pleiotropies that differentially affect maternal and paternal reproduction, or sexual and vegetative reproduction, are worthy of further study.

A multiscale approach to understanding the shared blue-orange flower color polymorphism in two Lysimachia species

BackgroundPolymorphisms are common in nature, but they are rarely shared among closely related species. Polymorphisms could originate through convergence, ancestral polymorphism, or introgression. Although shared neutral genomic variation across species is commonplace, few examples of shared functional traits exist. The blue-orange petal color polymorphisms in two closely related species, Lysimachia monelli and L. arvensis were investigated with UV-vis reflectance spectra, flavonoid biochemistry, and transcriptome comparisons followed by climate niche analysis.ResultsSimilar color morphs between species have nearly identical reflectance spectra, flavonoid biochemistry, and ABP gene expression patterns. Transcriptome comparisons reveal two orange-specific genes directly involved in both blue-orange color polymorphisms: DFR-2 specificity redirects flux from the malvidin to the pelargonidin while BZ1-2 stabilizes the pelargonidin with glucose, producing the orange pelargonidin 3-glucoside. Moreover, a reduction of F3’5’H expression in orange petals also favors pelargonidin production. The climate niches for each color morph are the same between the two species for three temperature characteristics but differ for four precipitation variables.ConclusionsThe similarities in reflectance spectra, biochemistry, and ABP genes suggest that a single shift from blue-to-orange shared by both lineages is the most plausible explanation. Our evidence suggests that this persistent flower color polymorphism may represent an ancestrally polymorphic trait that has transcended speciation, yet future analyses are necessary to confidently reject the alternative hypotheses.

Classification of Vase Life Day Based on Petal Colorimetric Data in Cut Lisianthus Using AutoML

This study investigated the potential of petal colorimetric data to classify vase life stages in cut lisianthus flowers (Eustoma grandiflorum). We analyzed the changes in the petal color space over time, focusing on the b* value as an indicator of senescence due to increasing yellowing caused by copigmentation. A comparative analysis was conducted between two cultivation methods: soil (S) and hydroponic (H) cultivation. The objective was to evaluate the performance of machine learning models trained to classify vase life stages based on petal color data. Automated machine learning models exhibited better performance in H-cultivated cut flowers, effectively distinguishing days within the vase life stages from Days 1 to 14 for H cultivation. Cut flowers cultivated under S conditions showed less variation in the color space from Days 1 to 9, maintaining a relatively uniform color range. This made it more difficult to distinguish the vase life stages compared to H cultivation. These findings demonstrate that petal color metrics can serve as reliable indicators of cut flower senescence and potentially facilitate nondestructive methods for classifying vase life stages. This technology holds promise for wider applications in the floriculture industry, improving quality control, and extending the vase life of various cut-flower crops.

Multi-omics analysis reveals anthocyanin synthesis is associated with drought stress tolerance in Chaenomeles speciosa flowers

Drought is one of the most severe abiotic stresses that limit plant growth. Chaenomeles speciosa, a Rosaceae plant of high ornamental value, exhibits noticeable changes in petal color under drought conditions. A multi-omics joint analysis was employed to examine the mechanism of flower color changes under drought conditions. We detected that the main reason for the change in flower color is the synthesis of anthocyanins, while ethylene (ET) and abscisic acid (ABA) also significantly increase. While ET and ABA are known to promote anthocyanin synthesis, their coordinated regulation under drought conditions remains unclear. This study aims to validate the hypothesis that ET/ABA mediated responses to drought regulate anthocyanin synthesis. The study inferred that the CsERF2, CsbZIP24–CsMYB6 signaling module plays a crucial role in the precise and dynamic regulation of anthocyanin synthesis. Yeast heterologous expression is used to demonstrate the drought tolerance function of candidate genes. Also, we performed transient expression analysis in petals suggests that these genes significantly contribute to anthocyanin accumulation under drought conditions. Moreover, Yeast one-hybrid and dual luciferase assays indicated that CsERF2 and CsbZIP24 can directly activate the expression of CsMYB6. Yeast two-hybrid, bimolecular fluorescence complementation, and Split-luciferase assays revealed interactions between CsERF2 and CsbZIP24 proteins, promoting anthocyanin biosynthesis. The study proposes a regulatory model for the mechanism of flower color change and aimed at exploring drought resistant ornamental plants and achieving their sustainable development.

A vacuolar protein MaSCPL1 mediates anthocyanin acylation modifications in blue-flowered grape hyacinth

The grape hyacinth is renowned for its profuse blue flowers, which confer substantial scientific and ornamental significance as well as considerable potential for industrial applications. The serine carboxypeptidase-like acyltransferases (SCPL-ATs) family is crucial for the blue flower coloration. To elucidate SCPL-ATs involved in anthocyanin modification in grape hyacinth, we performed a transcriptomic analysis of grape hyacinth SCPL-ATs. Through gene expression profiling, we identified a promising candidate gene, MaSCPL1, whose expression patterns corresponded with variations in anthocyanin content throughout petal coloration. Subsequently, the functional role of the MaSCPL1 gene was validated using the native petal regeneration system, and the silencing of MaSCPL1 led to a decreased total anthocyanin content and Dp3MG content in grape hyacinth petals. Furthermore, we employed yeast one-hybrid (Y1H), electrophoretic mobility shift assay (EMSA), and dual-luciferase assays to explore the regulatory interactions between the anthocyanin biosynthesis transcription factor MaMybA and the MaSCPL1 promoter. Our findings indicate that MaMybA can bind to the MaSCPL1 promoter and significantly activate its expression. Furthermore, the MaMybA-RNAi resulted in a substantial multifold reduction in the expression of MaSCPL1, implying that the regulation of MaSCPL1 expression is mediated by MaMybA. This study revealed the MaSCPL1 gene has been associated with anthocyanin acylated modification in grape hyacinth and elucidated the important role of the MaMybA-MaSCPL1 module in colouration grape hyacinth.

Color, proximate composition, bioactive compounds and antinutrient profiling of rose

Rose (Rosa sp.) is one of the most important ornamentals which is commercialize for its aesthetic values, essential oils, cosmetic, perfume, pharmaceuticals and food industries in the world. It has wide range of variations that is mostly distinguished by petal color differences which is interlinked with the phytochemicals, secondary metabolites and antinutrient properties. Here, we explored the color, bioactive compounds and antinutritional profiling and their association to sort out the most promising rose genotypes. For this purpose, we employed both quantitative and qualitative evaluation by colorimetric, spectrophotometric and visual analyses following standard protocols. The experiment was laid out in randomized complete block design (RCBD) with three replications where ten rose genotypes labelled R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 were used as plant materials. Results revealed in quantitative assessment, the maximum value of lightness, and the luminosity indicating a brightening of rose petals close to a yellow color from rose accessions R4, and R10, respectively which is further confirmed with the visually observed color of the respective rose petals. Proximate composition analyses showed that the highest amount of carotenoid and β-carotene was found in R10 rose genotype, anthocyanin and betacyanin in R7. Among the bioactive compounds, maximum tocopherol, phenolic and flavonoid content was recorded in R8, R6 and R3 while R1 showed the highest free radical scavenging potentiality with the lowest IC50 (82.60 µg/mL FW) compared to the others. Meanwhile, the enormous variation was observed among the studied rose genotypes regarding the antinutrient contents of tannin, alkaloid, saponin and phytate whereas some other antinutrient like steroids, coumarines, quinones, anthraquinone and phlobatanin were also figured out with their presence or absence following qualitative visualization strategies. Furthermore, according to the Principal Component Analysis (PCA), correlation matrix and cluster analysis, the ten rose genotypes were grouped into three clusters where, cluster-I composed of R3, R4, R5, R8, cluster-II: R9, R10 and cluster-III: R1, R2, R6, R7 where the rose genotypes under cluster III and cluster II were mostly contributed in the total variations by the studied variables. Therefore, the rose genotypes R9, R10 and R1, R2, R6, R7 might be potential valuable resources of bioactive compounds for utilization in cosmetics, food coloration, and drugs synthesis which have considerable health impact.

Natural variations in the Cis-elements of GhRPRS1 contributing to petal colour diversity in cotton.

The cotton genus comprises both diploid and allotetraploid species, and the diversity in petal colour within this genus offers valuable targets for studying orthologous gene function differentiation and evolution. However, the genetic basis for this diversity in petal colour remains largely unknown. The red petal colour primarily comes from C, G, K, and D genome species, and it is likely that the common ancestor of cotton had red petals. Here, by employing a clone mapping strategy, we mapped the red petal trait to a specific region on chromosome A07 in upland cotton. Genomic comparisons and phylogenetic analyses revealed that the red petal phenotype introgressed from G. bickii. Transcriptome analysis indicated that GhRPRS1, which encodes a glutathione S-transferase, was the causative gene for the red petal colour. Knocking out GhRPRS1 resulted in white petals and the absence of red spots, while overexpression of both genotypes of GhRPRS1 led to red petals. Further analysis suggested that GhRPRS1 played a role in transporting pelargonidin-3-O-glucoside and cyanidin-3-O-glucoside. Promoter activity analysis indicated that variations in the promoter, but not in the gene body of GhRPRS1, have led to different petal colours within the genus. Our findings provide new insights into orthologous gene evolution as well as new strategies for modifying promoters in cotton breeding.

Multi-omics analysis revealed the mechanism underlying flavonol biosynthesis during petal color formation in Camellia Nitidissima

BackgroundCamellia nitidissima is a rare, prized camellia species with golden-yellow flowers. It has a high ornamental, medicinal, and economic value. Previous studies have shown substantial flavonol accumulation in C. nitidissima petals during flower formation. However, the mechanisms underlying the golden flower formation in C. nitidissima remain largely unknown.ResultsWe performed an integrative analysis of the transcriptome, proteome, and metabolome of the petals at five flower developmental stages to construct the regulatory network underlying golden flower formation in C. nitidissima. Metabolome analysis revealed the presence of 323 flavonoids, and two flavonols, quercetin glycosides and kaempferol glycosides, were highly accumulated in the golden petals. Transcriptome and proteome sequencing suggested that the flavonol biosynthesis-related genes and proteins upregulated and the anthocyanin and proanthocyanidin biosynthesis-related genes and proteins downregulated in the golden petal stage. Further investigation revealed the involvement of MYBs and bHLHs in flavonoid biosynthesis. Expression analysis showed that flavonol synthase 2 (CnFLS2) was highly expressed in the petals, and its expression positively correlated with flavonol content at all flower developmental stages. Transient overexpression of CnFLS2 in the petals increased flavonol content. Furthermore, correlation analysis showed that the jasmonate (JA) pathways positively correlated with flavonol biosynthesis, and exogenous methyl jasmonate (MeJA) treatment promoted CnFLS2 expression and flavonol accumulation.ConclusionsOur findings showed that the JA-CnFLS2 module regulates flavonol biosynthesis during golden petal formation in C. nitidissima.

Chlorophyllase (PsCLH1) and light-harvesting chlorophyll a/b binding protein 1 (PsLhcb1) and PsLhcb5 maintain petal greenness in Paeonia suffruticosa ‘Lv Mu Yin Yu’

IntroductionGreen flowers are not an adaptive trait in natural plants due to the challenge for pollinators to discriminate from leaves, but they are valuable in horticulture. The molecular mechanisms of green petals remain unclear. Tree peony (Paeonia suffruticosa) is a globally cultivated ornamental plant and considered the ‘King of Flowers’ in China. The P. suffruticosa ‘Lv Mu Yin Yu (LMYY)’ cultivar with green petals could be utilized as a representative model for understanding petal-specific chlorophyll (Chl) accumulation and color formation. ObjectivesIdentify the key genes related to Chl metabolism and understand the molecular mechanism of petal color changes. MethodsThe petal color parameter was analyzed at five developmental stages using a Chroma Spectrophotometer, and Chl and anthocyanin accumulation patterns were examined. Based on comparative transcriptomes, differentially expressed genes (DEGs) were identified, among which three were functionally characterized through overexpression in tobacco plants or silencing in ‘LMYY’ petals. ResultsDuring flower development and blooming, flower color changed from green to pale pink, consistent with the Chl and anthocyanin levels. The level of Chl demonstrated a similar pattern with petal epidermal cell striation density. The DEGs responsible for Chl and anthocyanin metabolism were characterized through a comparative transcriptome analysis of flower petals over three critical developmental stages. The key chlorophyllase (PsCLH1) and light-harvesting chlorophyll a/b binding protein 1 (PsLhcb1) and PsLhcb5 influenced the Chl accumulation and the greenness of ‘LMYY’ petals. ConclusionPsCLH1, PsLhcb1, and PsLhcb5 were critical in accumulating the Chl and maintaining the petal greenness. Flower color changes from green to pale pink were regulated by the homeostasis of Chl degradation and anthocyanin biosynthesis. This study offers insights into underlying molecular mechanisms in the green petal and a strategy for germplasm innovation.

Variation and Phenetic Relationship of Passiflora spp. in Yogyakarta Based on Morphological and Anatomical Characters

Passiflora spp. or passion fruit is a tropical plant that is often used as a food source. The large morphological variations of Passiflora cause difficulties in identifying the species. The objectives of the study are to identify the specific morphological and anatomical characters of Passiflora spp. in Yogyakarta and to determine their phenetic relationship for identification. A total of 15 samples of Passiflora were taken by purposive sampling technique from Bantul, Sleman, Kulon Progo, and Yogyakarta City, and then carried through the morphological and anatomical characterization. The morphological characters observed stems, leaves, and flowers, while the anatomical characters observed leaves. The results show that the observed samples are identified as four species, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis. The P. edulis species consists of two forms, P. edulis f. flavicarpa and P. edulis f. edulis. The variation of morphological character lie in young stem shape, leaf shape, the texture of stem and leaf surface, bract shape and color, sepal and petal color, and the presence of a purple corona ring. While the variation of anatomical characters lie in the pattern of the vascular bundles, the shape of the upper and lower sides of the leaf veins, the shape and size of the palisade cells, as well as the type and density of stomata. Based on the phenetic analysis on the 0.8 phenon line, four main clusters were formed, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis.

CHRYSANTHEMUM FLOWERS AS A SOURCE OF IDEAS FOR CREATING PARTY WEAR

Chrysanthemums have several types of flowers with attractive petal shapes and colours. This research describes the making process and the result of men's and women's party wear with chrysanthemums as decorative trims. This research method uses a double-diamond design process consisting of four stages: discovered, defined, developed, and delivered. The discovery stage is the stage of finding the source of ideas as outlined in the mood board, inspired by the arrangement of petals and varied colours in flowers. The defined stage was to create eight designs of women's party wear and four designs of men's party wear based on the mood board. In the development stage, the women's party fashion will be created using the draping technique on a medium-sized mannequin, and the men's party wear will be created using a large-size construction pattern. The deliver stage is the stage of making decorative trims in the form of chrysanthemum flowers and fabric manipulation tucking as the centre of attention on the apparel. The result of the research was a party dress that was based on the source of the chrysanthemum flower idea. Recommendations for future research can explore the application of chrysanthemum flower idea sources on different designs.

Why are the inner and outer sides of many flower petals differently coloured?

The flower perianth has various, non-mutually exclusive functions, such as visual signalling to pollinators and protecting the reproductive organs from the elements and from florivores, but how different perianth structures and their different sides play a role in these functions is unclear. Intriguingly, in many species there is a clear colour difference between the different sides of the perianth, with colour patterns or pigmentation present on only one side. Any adaptive benefit from such colour asymmetry is unclear, as is how the asymmetry evolved. In this viewpoint paper, we address the phenomenon of flowers with differently coloured inner and outer perianth sides, focusing on petals of erect flowers. Guided by existing literature and our own observations, we delineate three non-mutually exclusive evolutionary hypotheses that may explain the factors underlying differently coloured perianth sides. The pollen-protection hypothesis predicts that the outer side of petals contributes to protect pollen against UV radiation, especially during the bud stage. The herbivore-avoidance hypothesis predicts that the outer side of petals reduces the flower's visibility to herbivores. The signalling-to-pollinators hypothesis predicts that flower colours evolve to increase conspicuousness to pollinators. The pollen-protection hypothesis, the herbivore-avoidance hypothesis, and the signalling-to-pollinators hypothesis generate largely but not entirely overlapping predictions about the colour of the inner and outer side of the petals. Field and laboratory research is necessary to disentangle the main drivers and adaptive significance of inner-outer petal side colour asymmetry.

Methylation Modification in Ornamental Plants: Impact on Floral Aroma and Color.

Methylation represents a crucial class of modification that orchestrates a spectrum of regulatory roles in plants, impacting ornamental characteristics, growth, development, and responses to abiotic stress. The establishment and maintenance of methylation involve the coordinated actions of multiple regulatory factors. Methyltransferases play a pivotal role by specifically recognizing and methylating targeted sites, which induces alterations in chromatin structure and gene expression, subsequently influencing the release of volatile aromatic substances and the accumulation of pigments in plant petals. In this paper, we review the regulatory mechanisms of methylation modification reactions and their effects on the changes in aromatic substances and pigments in plant petals. We also explore the potential of methylation modifications to unravel the regulatory mechanisms underlying aroma and color in plant petals. This aims to further elucidate the synthesis, metabolism, and regulatory mechanisms of various methylation modifications related to the aroma and color substances in plant petals, thereby providing a theoretical reference for improving the aroma and color of plant petals.

Heat-induced modulation of flavonoid biosynthesis via a LhMYBC2-Mediated regulatory network in oriental hybrid lily

Global warming significantly threatens crop production, and adversely affects plant physiology due to rising temperatures. Oriental hybrid lily, an ornamental plant of economic importance, experiences flower color changes in response to elevated temperatures. Anthocyanins belong to a subgroup of flavonoids and are the primary pigments responsible for the coloration of oriental hybrid lily petals. However, the regulatory mechanisms governing flavonoid biosynthesis under high temperature conditions in lilies remain poorly understood. In this study, we revealed the altered metabolite profiles in flavonoid biosynthesis using quasi-targeted metabolomic and transcriptomic analyses. Isoflavonoids accumulate substantially under high temperature conditions, whereas the accumulation of anthocyanin decreases. The expression of the isoflavone reductase gene (LhIFR) and the transcription factor LhMYBC2 were upregulated in response to high temperatures. The LhMYBC2 protein, which belongs to Subgroup 4-AtMYB4, competes with the anthocyanin positive regulator LhMYBA1 for the LhTT8 partner, thereby repressing the formation of a positively regulated transcription complex. Heterologous overexpression of LhMYBC2 in tobacco led to reduced anthocyanin accumulation and increased isoflavonoid accumulation, corroborating its role in inhibiting anthocyanin biosynthesis. This study proposes a regulatory model wherein LhMYBC2 acts as a mediator of flavonoid biosynthesis, influencing the coloration of lily flowers under high-temperature stress. These findings deepen our understanding of the metabolic and transcriptional responses of lily to heat stress and underscore the potential role of LhMYBC2 in mitigating anthocyanin accumulation.

Integrated Metabolomics and Transcriptomics Reveal the Key Role of Flavonoids in the Cold Tolerance of Chrysanthemum.

Chrysanthemum (Chrysanthemum morifolium, ground-cover Chrysanthemums), one of the important garden flowers, has a high ornamental and economic value. However, its ornamental value is significantly diminished by the low temperature experienced in northeastern China. Here, metabolomics and transcriptomics were performed on three Chrysanthemum cultivars before and after a low temperature to investigate the dynamic metabolite changes and the molecular regulatory mechanisms. The results showed that 1324 annotated metabolites were detected, among which 327 were identified as flavonoids derived from Chrysanthemum. The accumulation of metabolites and gene expression related to the flavonoid biosynthesis pathway significantly increased in the three cultivars under the low temperature, indicating flavonoid metabolism actively participates in the Chrysanthemum cold response. Specifically, the content of cyanidin and pelargonidin derivatives and the expression of anthocyanin biosynthesis genes significantly increases in XHBF, providing a reasonable explanation for the change in petal color from white to purple under the low temperature. Six candidate UDP-glycosyltransferase genes involved in the glycosylation of flavonoids were identified through correlation networks and phylogenetic analysis. CmNAC1, CmbZIP3, and other transcription factors potentially regulating flavonoid metabolism and responding to low temperatures were discovered by correlation analysis and weighted gene co-expression network analysis (WGCNA). In conclusion, this study elucidated the specific response of flavonoids to low temperatures in Chrysanthemums, providing valuable insights and metabolic data for investigating cold tolerance.

Molecular and Phytochemical Characteristics of Flower Color and Scent Compounds in Dog Rose (Rosa canina L.).

This study delves into the chemical and genetic determinants of petal color and fragrance in Rosa canina L., a wild rose species prized for its pharmacological and cosmetic uses. Comparative analysis of white and dark pink R. canina flowers revealed that the former harbors significantly higher levels of total phenolics (TPC) and flavonoids (TFC), while the latter is distinguished by elevated total anthocyanins (TAC). Essential oils in the petals were predominantly composed of aliphatic hydrocarbons, with phenolic content chiefly constituted by flavonols and anthocyanins. Notably, gene expression analysis showed an upregulation in most genes associated with petal color and scent biosynthesis in white buds compared to dark pink open flowers. However, anthocyanin synthase (ANS) and its regulatory gene RhMYB1 exhibited comparable expression levels across both flower hues. LC-MS profiling identified Rutin, kaempferol, quercetin, and their derivatives as key flavonoid constituents, alongside cyanidin and delphinidin as the primary anthocyanin compounds. The findings suggest a potential feedback inhibition of anthocyanin biosynthesis in white flowers. These insights pave the way for the targeted enhancement of R. canina floral traits through metabolic and genetic engineering strategies.