Search Results (146)

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

Across plants, the PEBP gene family is reported to regulate storage organ formation, developmental plasticity, and floral transitioning. However, its evolutionary dynamics and functional diversification within Allium species remain poorly understood. In this study, we performed genomic and transcriptomic analyses of the PEBP gene family across three economically important Allium species, including Allium fistulosum (bunching onion), Allium sativum (garlic), and Allium cepa (onion), identifying 19, 17, and 21 PEBP genes, respectively. The genes were assigned into five subfamilies (FT-like, TFL1-like, MFT-like, BFT-like, and PEBP-like), with MFT-like members being the most abundant. Structural analysis revealed strong conservation of key motifs (e.g., GxHR and DPDxP) across species, while substantial variation in intron–exon organization suggested subfunctionalization. Collinearity analysis indicated that segmental duplication primarily drove PEBP gene expansion in garlic and onion, whereas tandem duplication was absent in bunching onion. Promoter analysis showed enrichment of light- and hormone-related cis-regulatory elements, implicating their involvement in environmental and hormonal regulation. Expression profiling demonstrated clear tissue specificity, with AsPEBP11/13/14/16/19 exhibiting significantly higher expression in normal flowers than in abnormal ones, suggesting key roles in floral morphogenesis. Together, these findings will prove useful for future breeding programs aimed at improving reproductive development and fertility in Allium species. Full article

Background: Rosa chinensis, commonly known as the Chinese rose, is one of the most economically significant ornamental plants worldwide. The Rosa chinensis cultivar ‘Rainbow’s End’ notably transitions in color from yellow to red throughout its blooming phase; however, the chemical and molecular foundations underlying this floral color transformation remain inadequately understood. Methods: This study used the petals of the Rosa ‘Rainbow’s End’ cultivar at four developmental stages (R1, R2, R3, and R4) for targeted metabolomic and transcriptomic analyses. Results: Targeted metabolomic analyses revealed that the majority of anthocyanidin metabolites were highest at stages R2 and R3 and lowest at R1 and R4. In contrast, most carotenoid metabolites reached their highest levels at R1 and declined continuously from R2 to R4. These results were consistent with the color phenotype of Rosa ‘Rainbow’s End’ petals and suggested that both anthocyanins and carotenoids play critical roles in flower color variation. Specifically, an upregulation of CHS, ANS, and UGT genes in the anthocyanin biosynthesis pathway was observed in R2 and R3, coinciding with the expression of two MYB transcription factors (MYB14 and MYB54). Conversely, consistent downregulation of PSY, PDS, Z-ISO, ZDS, CHYB, and NCED genes in the carotenoid biosynthesis pathway was detected in R2 to R4 and was associated with four MYB transcription factors (MYB20, MYB43, MYB44, and MYB86). Conclusions: Rosa ‘Rainbow’s End’ is an excellent model for studying variations in flower color. The expression patterns of the identified structural genes involved in anthocyanin and carotenoid biosynthesis pathways, along with the related MYB transcription factors, were aligned with the levels of metabolite changes in the petals of four flowering stages. These genes and transcription factors are likely responsible for the color shifts in Rosa ‘Rainbow’s End’. This study clarifies the mechanisms underlying color changes in Rosa ‘Rainbow’s End’ and provides a theoretical basis for future flower breeding efforts. Full article

Floral volatile terpenoids are known to play important roles in plant pollination biology by attracting animal pollinators, repelling antagonists, and enhancing resistance to potential microbial pathogens. The terpenoid blend emitted by a flower is usually plant-lineage specific and is primarily determined by a set of versatile terpene synthases (TPSs), which catalyze the final step of diverse terpenoid synthesis. The strongly scented flower of Jasminum sambac (L.) Aiton emits linalool and α-farnesene, which dominate the nocturnal floral VOCs, yet the corresponding TPSs have not been identified. Here, we show that four TPS enzymes are responsible for the synthesis of a mixture of volatile terpenoids in the flower, based on their highly correlated and almost exclusive expression in the petal, as well as their enzymatic characterizations in vitro and in Nicotiana benthamiana Domin. JsTPS01 (TPS-a) acts as a sesquiterpene synthase, producing τ-cadinol in yeast at levels that mirror its rhythmic expression in petals. JsTPS02 (TPS-b) carries a plastid-targeting transit peptide, localizes to chloroplasts/plastids, and converts geranyl diphosphate (GPP) to linalool with high affinity (K_m = 28.2 ± 3.4 µM). JsTPS03 is a TPS-b clade member that can convert farnesyl diphosphate (FPP) to farnesol with a K_m of 14.4 ± 5.9 μM in an in vitro assay using isolated yeast vehicles. JsTPS04 (TPS-e/f) exhibits dual targeting—cytosolic in protoplasts of Arabidopsis thaliana (L.) Heynh, but plastidic in J. sambac petals—and functions as a bifunctional mono-/sesqui-TPS, forming linalool from GPP (K_m = 2.5 ± 0.3 µM) and trans-nerolidol from FPP (K_m = 7.6 ± 0.6 µM). Transient expression in N. benthamiana leaves further confirmed its in-planta linalool production. Collectively, we identified four preferentially expressed terpene synthases that contribute to the production of linalool, τ-cadinol, trans-nerolidol, and farnesol in J. sambac. Full article

Gynogenesis offers a promising route for doubled haploid (DH) production in Cucurbita, yet efficient protocols remain scarce. This study established a reproducible ovary culture system for Cucurbita pepo and evaluated zeatin riboside (ZR) as an alternative cytokinin. Ovaries collected at anthesis and one day before were cultured to screen nine media with different cytokinin–auxin combinations. Subsequently, four optimized ZR-based formulations were evaluated. Both floral stages showed morphogenic activity, but embryo formation occurred almost exclusively in pre-anthesis ovaries. Among ZR treatments, E6.1 (1 mg·L⁻¹ ZR + 3 mg·L⁻¹ NAA, 30 g·L⁻¹ sucrose) achieved the highest embryogenic output (approximately 97 embryos per 100 explants), while high-sucrose media (120 g·L⁻¹) induced abundant swollen ovules but poor conversion, suggesting that excessive osmotic pressure promotes morphogenesis but hampers embryogenic transition. In total, 415 embryos were obtained, and 52 regenerants were analyzed by flow cytometry, confirming haploid, diploid, and mixoploid plants and evidencing spontaneous chromosome doubling during in vitro development. A categorical A–D scoring system enabled early prediction of embryogenic potential. This represents the first successful application of ZR in cucurbit gynogenesis and highlights its value as a biologically compatible cytokinin for DH production. The findings open new avenues for testing ZR-based formulations in other Cucurbita species under different auxin and sucrose regimes. Full article

Vegetative to reproductive phase transition is an important developmental process in flowering plants, regulated in part by microRNAs that repress target genes post-transcriptionally. However, the role of miR156 and its target Squamosa Promoter Binding Protein-Like (SPL) transcription factors remains poorly understood. In this study, we identified 14 SPL gene members in spinach and analyzed their expression during phase transition. Genome-wide identification and transcriptome-based analysis revealed that 11 of these genes are likely direct targets of SpmiR156a/b/c/d, with binding sites confirmed by sequence-based interaction prediction. Expression profiling showed that SpSPL3 and SpSPL8, which are strongly repressed during vegetative growth, were significantly regulated during the transition phase. Gene Ontology (GO) and promoter cis-element analyses support that SPL genes are involved in hormonal pathways and floral development Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) further validated the transcriptome expression patterns of key SPL genes. Together, these findings outline a regulatory framework in which SpmiR156 modulates SpSPL gene activity to control developmental phase change in spinach, highlighting both the expansion and functional diversification of the SPL gene and the central role of SpmiR156 in vegetative to reproductive transition. Full article

The transition to flowering in Arabidopsis thaliana is governed by complex transcriptional regulatory networks, in which promoter-associated cis-regulatory elements integrate both developmental and environmental cues. To investigate these regulatory interactions, we analyzed promoter motifs of 18 flowering-related genes using curated motif resources, including the Eukaryotic Promoter Database (EPD) and JASPAR, applying stringent statistical thresholds. Transcription factors (TFs), which were predicted to bind across all examined promoters, were designated as putative master regulators, resulting in the identification of 36 candidates, predominantly belonging to the MADS-box, DOF, and IDD families. Positional analyses revealed both proximal and distal binding sites, including a notable motif at −1024 in PISTILLATA and at +466 in SEPALLATA3, potentially indicative of autoregulatory control. Comparative analysis further identified 96 gene-specific associations, reflecting a balance between shared and specialized regulatory mechanisms. Treatment with β-aminobutyric acid (BABA), which has a flowering delaying effect, repressed SQUAMOSA and increased DOF-type TFs, indicating a chromatin-associated reprogramming process, which may coordinate the transcriptional suppression of flowering activators. These findings refine current models of floral regulatory networks and provide testable hypotheses regarding autoregulatory and cross-regulatory circuits in the control of flower development. Full article

As an emerging field of life science, epigenetics plays a pivotal role in regulating gene expression. Epigenetic modifications including histone modifications, DNA methylation, chromatin remodeling, non-coding RNAs, and RNA modifications (particularly m⁶A methylation) play crucial roles in fine-tuning plant developmental processes. Among these, floral transition marks a key developmental switch from vegetative to reproductive growth, orchestrated by complex interactions between endogenous signals (such as age and hormones) and environmental cues (such as photoperiod and temperature). Recent advances have uncovered that epigenetic mechanisms act as molecular bridges integrating these signals to ensure flowering occurs under optimal conditions. This review synthesizes the current understanding of epigenetic control in the six canonical flowering pathways—photoperiod, vernalization, autonomous, thermosensory, gibberellin, and age-dependent pathways—with a particular emphasis on the emerging role of m⁶A RNA modification. We also discuss the crosstalk among epigenetic layers and highlight the translational potential of epigenetic engineering in optimizing flowering time and crop adaptation. Full article

DnaJ proteins are established regulators of multiple physiological processes in plants, but their systematic identification and functional characterization in cotton remains largely uncharacterized, particularly regarding their roles in floral developmental regulation. In this study, based on genome-wide analysis of Gossypium hirsutum L., 372 DnaJ genes were systematically identified and phylogenetically classified into four distinct clades (I–IV). These genes exhibited non-uniform chromosomal distribution. Structural analysis revealed clade-specific variations in intron numbers and conserved motifs. Cis-acting element profiling indicated the roles of DnaJs in modulating biosynthetic and metabolic regulation during both vegetative and reproductive development in cotton. Transcriptomic analysis highlighted tissue-specific expression patterns, with GhDnaJ316 showing preferential expression in anthers and filaments. Functional validation via VIGS-mediated silencing confirmed GhDnaJ316 as a negative regulator of floral transition, accelerating budding by 7.7 days and flowering by 9.7 days in silenced plants. This study elucidates the genomic architecture of GhDnaJs, demonstrates GhDnaJ316’s critical role in floral development and provides insights for molecular breeding in early-maturing cotton. Full article

Blue light (BL) is a key environmental signal influencing plant flowering, yet its role in floral development beyond the transition phase remains underexplored. This review provides a comprehensive synthesis of current research on BL-mediated floral development, with a particular emphasis on horticultural crops grown in a controlled environment. Unlike prior reviews that focus primarily on floral induction, this article systematically examines BL’s effects on later stages of flowering, including floral organ morphogenesis, sex expression, bud abortion, flower opening, scent emission, coloration, pollination, and senescence. Drawing on evidence from both model plants (e.g., Arabidopsis thaliana) and crop species, this review identifies key photoreceptors, hormonal regulators, and signaling components involved in BL responses. It also highlights species-specific and context-dependent outcomes of BL manipulation, proposes mechanistic hypotheses to explain conflicting findings, and outlines critical knowledge gaps. By integrating molecular, physiological, and environmental perspectives, this review offers a framework for optimizing BL applications to improve flowering traits and postharvest quality in horticultural production systems. Full article

Broccoli (Brassica oleracea L. var. italica) is a biennial or annual herbaceous plant belonging to the species Brassica oleracea in the genus Brassica of the Cruciferae family. The green flower curd serves as the primary edible organ, with its development and preservation critically determining broccoli yield and quality. Given that these processes are regulated by flowering time, understanding the mechanisms underlying floral transition is essential for enhancing broccoli yield and quality. This study aimed to identify the MADS-box family in broccoli and to investigate the function of the BoAGL8 gene in floral induction. We identified a total of 176 MADS-box genes, of which 54 genes were up-regulated and 50 genes were down-regulated under low-temperature treatment. Notably, the expression of BoAGL8 was up-regulated by 6.70-fold under low-temperature induction, prompting us to select and clone this gene for further analysis. Tissue-specific expression profiling further revealed that BoAGL8 is expressed at relatively high level in both mature and young leaves. After 15 days of low-temperature treatment, BoAGL8 expression in shoot tip was significantly upregulated compared to untreated controls. Subcellular localization analysis showed that BoAGL8 protein was located to the nucleus. Ectopic over-expression of BoAGL8 in Arabidopsis exhibited accelerated bolting and flowering, reduced rosette leaf number, and increased seed yield per plant compared to wild-type plants. Furthermore, compared to wild-type controls, transgenic lines exhibited upregulated expression of AtFT, AtAP1 and AtSEP3, alongside downregulation of SVP expression. The above results indicate that BoAGL8 may play a key regulatory role in the process of floral organ development in broccoli, providing an important theoretical basis for future research on flowering time regulation and breeding in broccoli. Full article

Michelia ‘Xin’ is an evergreen rare ornamental tree species that undergoes FBD only once but blooms twice a year. However, the molecular mechanisms controlling its FBD process remain largely unknown. This study characterized the FBD process and delved into the key molecular regulatory mechanisms through transcriptomic and metabolomic analyses of developing flower buds. FBD in Michelia ‘Xin’ was characterized into five stages, including vegetative (T1), floral meristem transition (T2), tepal primordia differentiation (T3), stamen primordia differentiation (T4), and pistil primordia differentiation (T5). Analyses revealed a stage-specific metabolic and transcriptional regulation of FBD, with increasing numbers of differential metabolites and a decreasing number of DEGs from T1 to T5. Most phytohormone and transcription factor-related DEGs were highly induced from T2. The down-regulation of dormancy-associated protein homologs and CONSTANS-LIKE proteins associated with significant induction of flowering-promoting factor, CLAVATA3, trichome birefringence-like, and GRAVITROPIC IN THE LIGHT proteins was essential for the induction and reproductive organs’ development. Porphyrin biosynthesis, chlorophyll a-b binding proteins, DNA replication, flavonoid biosynthesis, and starch and sucrose metabolism were also significantly induced from T2. Key pivotal candidate genes were screened out. Our results provide fundamental resources for dissecting the molecular network regulating FBD and molecular-assisted flowering control in Michelia ‘Xin’. Full article

The transition from outcrossing to self-pollination is an evolutionary process in angiosperms. However, the changes in floral volatile composition during this process and their impacts on the behavior of pollinators are poorly understood. Therefore, this study investigated the potential differences in the floral volatile profiles and pollinator attraction capabilities of three invasive Bidens species. The results indicated that Bidens pilosa var. radiata (BH), which serves as a transitional species between facultative outcrossing and obligate outcrossing attracts a greater diversity and abundance of pollinators such as Apis cerana compared to the more self-compatible Bidens frondosa (DL) and Bidens pilosa var. pilosa (SY). Furthermore, a total of 37, 33, and 34 Volatile Organic Compounds (VOCs) were identified in the floral volatiles of BH, DL, and SY, respectively, with no discernible trend of decreased number of floral VOCs owing to increased self-pollination ability. Moreover, eleven significantly different compounds in the floral volatiles of the three Bidens species were obtained. Among these (E)-β-Ocimene (18.31 ± 1.10%) and (Z)-β-Ocimene (33.93 ± 3.49%) in the floral volatiles of BH (52.24 ± 4.59%) was significantly higher than that of DL (1.72 ± 0.50%) and SY (0.32 ± 0.19%). Additionally, Y-tube olfactometer behavioral assays indicated that (E)- and (Z)-β-Ocimene significantly attracted A. cerana. These findings suggested that (E)- and (Z)-β-Ocimene contribute to the attractiveness of BH to local pollinators. Furthermore, it can be inferred that within Bidens, stronger self-pollination ability reduces the relative content of VOCs—such as (E)- and (Z)-β-Ocimene—used to attract generalist pollinators. Full article

Carpel number has been recognized as a critical factor influencing fruit size, ultimately determining yield and economic efficiency. The WUSCHEL (WUS) protein is essential for maintaining stem cell homeostasis in the floral meristem. Its expression level directly influences the size of the floral meristem (FM), thereby determining the number of floral organs in Arabidopsis thaliana, Solanum lycopersicum, and Cucumis sativus. While its role remained largely unexplored in grapevine (Vitis vinifera). This study cloned the VvWUS gene from the polycarpic grape cultivar ‘Jizaomi’. Transgenic tomato lines expressing VvWUS heterologously exhibited accelerated floral transition, enhanced carpel/floral organ initiation, and had significantly higher locule numbers relative to wild type. Furthermore, direct binding of VvWUS to the VvAGAMOUS (VvAG) promoter and activation of VvAG expression were demonstrated through yeast one-hybrid (Y1H) and dual-luciferase (LUC) assays. These findings elucidated the molecular function of VvWUS in grape carpel development, providing a foundational basis for molecular breeding strategies targeting large-berry grape varieties. Full article

Background/Objectives: Bolting in lettuce (Lactuca sativa L.) is highly sensitive to elevated temperatures, leading to premature flowering and reduced crop quality and yield. Although SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) is a well-known floral integrator in Arabidopsis, its role in heat-induced bolting in lettuce remains unclear. Methods: In this study, we generated CRISPR/Cas9-mediated LsSOC1 knockout (KO) lines and evaluated their phenotypes under high-temperature conditions. Results: LsSOC1-KO lines exhibited delayed bolting up to 18.6 days, and stem elongation was reduced by approximately 3.8 cm, which is equivalent to a 36.1% decrease compared to wild-type (WT) plants. Transcriptome analysis of leaf and bud tissues identified 32 up-regulated and 10 down-regulated genes common to leaf tissue (|log₂FC| ≥ 1, adjusted p < 0.05). Among them, GA20-oxidase1 was significantly down-regulated in both tissues, which may have contributed to delayed floral transition and possibly to reduced stem elongation, although tissue-specific regulation of gibberellin metabolism warrants further investigation. In contrast, genes encoding heat shock proteins, ROS-detoxification enzymes, and flavonoid biosynthetic enzymes were up-regulated, suggesting a dual role of LsSOC1 in modulating thermotolerance and floral transition. qRT-PCR validated the sustained suppression of flowering-related genes in LsSOC1 KO plants under 37 °C heat stress. Conclusions: These findings demonstrate that LsSOC1 is a key integrator of developmental and thermal cues, orchestrating both bolting and stress-responsive transcriptional programs. Importantly, delayed bolting may extend the harvest window and improve postharvest quality in lettuce, highlighting LsSOC1 as a promising genetic target for breeding heat-resilient leafy vegetables. Full article