Search Results (156)

Background/Objectives: The coordination of flowering and dormancy represents a fundamental adaptive strategy for perennial plant survival. Recent studies have demonstrated that AIL1 homologs act as integrators of short-day signals, playing pivotal roles in seasonal growth cessation and dormancy regulation in poplar. Despite these advances, whether AIL1-mediated regulatory mechanisms are conserved in Platanus acerifolia, a species with distinct phylogenetic and ecological characteristics, remains an open question. Methods: In this study, two AIL1 homologs, PaAIL1a and PaAIL1b, were isolated from P. acerifolia. Their biological functions were systematically investigated through sequence analysis, spatiotemporal expression profiling, environmental stress treatments, yeast one-hybrid assays, and luciferase (LUC) transient expression assays. Results: PaAIL1s (PaAIL1a and PaAIL1b) exhibited ubiquitous expression across diverse tissues and organs, functioning as mediators of photoperiod and temperature signaling to orchestrate bud dormancy regulation. Interaction and activation assays placed these factors downstream of PaFUL proteins. While displaying functional redundancy in dormancy induction and floral development, the paralogs underwent distinct subfunctionalization: PaAIL1a specifically regulated flowering initiation and dormancy release, whereas PaAIL1b acted predominantly during the ecodormancy phase. Conclusions: These results establish PaAIL1 genes as critical integrators of environmental signals and developmental programs, governing seasonal growth dynamics in this species. Full article

Monarch butterflies have declined in both eastern and western populations. Conservation initiatives that support this imperiled species are being implemented in lands managed by the energy and transportation sectors. Vegetation management strategies that encourage the presence of milkweed (Asclepias spp.), the larval host of monarch butterflies (Danaus plexippus), or floral resources to support pollinators are being practiced across North America; however, survey methods to evaluate the success of these strategies vary in accuracy and scalability. In this study, we compared five methods to quantify milkweed stem density and land cover estimates: (1) Site al, (2) Transect plot, (3) Square plot, (4) Large transect (informed by the Monarch CCAA methodology), and (5) Machine learning of images collected by UAVs. These methods encompass full coverage ground counts, partial ground counts, and aerial imagery using object-based image analysis. Sites included distribution, transmission, and gas line ROWs, solar arrays, and transportation easements. We found that Site al and Machine learning most consistently quantified milkweed stem density across sites. Partial ground count methods were likely to over or underestimate milkweed populations. Habitat characteristics (woody, broadleaf, grass, and bare ground) estimates were inconsistent across method and site. The intent of this study was to provide land managers with insight as to the most accurate, efficient, and economical approach to quantify milkweed populations and habitat characteristics. Full article

This study investigated the aroma characteristics of three grades of raw tea leaves and their corresponding jasmine tea products from Guangxi, China. Aromatic profiles of jasmine tea varieties were analysed using two-dimensional gas chromatography-olfactory-mass spectrometry (GC×GC-O-MS), stir bar sorptive extraction (SBSE), and descriptive sensory evaluation. Chemometric methods were applied to compare sensory scores with instrumental data. Volatile compound concentrations and relative odour activity values (r-OAVs) were calculated. The results indicated significant differences in base tea leaf quality: high-grade tea leaf G1 exhibited pure, sweet characteristics, serving as an excellent aroma-absorbing carrier. The scenting process significantly imparted jasmine fragrance to the finished product, although its efficacy was constrained by tea leaf grade. GH1 finished tea exhibited a fresh, vibrant, and rich aroma with a sweet, mellow fragrance and high floral integration. In contrast, GH3, due to its inferior base material quality, yielded a weak aroma after scenting with limited quality improvement. The initial quality of the tea base is the fundamental determinant of the upper limit of the finished jasmine tea’s sensory quality, while the scenting process is the core means of shaping its signature floral aroma. The combination of high-quality tea leaves and precise scenting techniques is essential for developing the fresh, vibrant, and rich flavour profile of premium jasmine tea. This study reveals that the flavour formation of jasmine tea originates from the foundational quality of the tea leaves, providing a theoretical basis for monitoring the aroma quality of jasmine tea produced from different grades of tea leaves. Full article

Deciphering the molecular regulatory networks of panicle development is essential for the genetic improvement of crop yield. However, to date, no systematic studies of gene expression across different panicle developmental stages have been performed in foxtail millet. In this study, a transcriptome analysis of foxtail millet panicle was conducted in four stages of development spanning from the initiation of primary branches to floral organ differentiation. A total of 20,377 expressed genes were identified, including 10,647 differentially expressed genes. Fuzzy C-means clustering detected stage-specific expressed homologs of key transcription regulators, which may be involved in plant organ morphogenesis. Moreover, 1215 transcription factors of 55 families were identified. Members of the MADS-box and GRAS transcription factors showed stage-specific expression patterns, whose conservation was useful in discovering genes related to foxtail millet panicle development. Our analysis was further substantiated by the functional characterization of SiSOC1, whose expression exhibited a gradual upregulation across the four developmental stages. SiSOC1 was identified and validated, which revised the annotation of the reference genome. Overexpression of SiSOC1 markedly accelerated the heading of foxtail millet under long-day and short-day conditions, validating its function in regulating the heading date. In summary, this study systematically identified the transcriptomic landscape of foxtail millet panicle development, and elucidated key regulatory genes. These results provide a theoretical foundation and gene resources for facilitating the molecular breeding of foxtail millet. Full article

Korean pine (Pinus koraiensis) is a vital woody oil tree species native to Northeast Asia, with its pine nuts serving as the primary global source of edible pine nuts globally due to their rich nutritional content. Currently, seed yield from Korean pine is low and unstable, failing to meet the market demand. The limited number of female cones is the primary factor restricting its yield. MADS-box family members are crucial in regulating the initiation, differentiation, and morphogenesis of floral organs. However, systematic identification and characterization of MADS-box proteins in Korean pine have not been reported. This study utilized transcriptome data from reproductive and vegetative buds during the flower bud differentiation stage of Korean pine to comprehensively identify MADS-box family members through bioinformatics analysis and molecular biology approaches. A total of 37 PkMADS-box genes were identified, including 6 type I and 31 type II (MIKC) genes, which were classified into 8 subfamilies. The physicochemical properties, conserved domains, conserved motifs, protein structures, gene expression profiles, and protein–protein interaction networks of these genes were analyzed. Key genes associated with physiological differentiation (flower induction) and sexual organogenesis were identified based on expression patterns during flower bud differentiation and flower organ development. Among these, PkMADS4 and PkMADS26 are likely involved in positively regulating flower induction, while PkMADS9 plays a role in the morphological differentiation of sexual organs in a dose-dependent manner and overexpression of PkMADS9 promoting early flowering in transgenic Arabidopsis. These genes were also identified as key candidates for regulating reproductive phase changes and strobilus development. This study provides a theoretical foundation for further investigation of MADS-box genes in reproduction and offers insights into genetic improvements aimed at enhancing the seed yield of Korean pine. Full article

Hazelnut (Corylus avellana L.) productivity may be constrained by source–sink imbalances. However, field-based evidence under commercial orchard conditions on the use of branch girdling and cytokinin sprays in hazelnut remains limited. This two-season study conducted in a commercial orchard evaluated the effects of branch girdling (30 mm in October; 3 mm in November) and foliar 6-benzyladenine (6-BA; 30 or 60 mg L⁻¹) applications on the physiology, yield, and nut quality of ‘Tonda di Giffoni’ under Mediterranean conditions. Treatments were evaluated in a randomized complete block design (eight trees per treatment) using linear mixed models. Neither girdling nor 6-BA significantly improved fruit set or estimated yield (p > 0.18) and branch productivity was primarily determined by the initial floral load. However, intense October girdling markedly reduced return bloom (p < 0.001) and impaired gas exchange. In contrast, late-season or split 6-BA applications (T7–T9) consistently increased kernel yield (%), although sometimes at the expense of fruit size and weight. These findings suggest that while the total yield remained unchanged, specific treatments modulated physiological and quality traits, with late 6-BA enhancing kernel fill and early girdling posing risks to subsequent reproductive performance. Full article

Background/Objectives: This study was based on the joint analysis of transcriptome and metabolome to explore the key genes and metabolic pathways of gardenia single flower petal number variation and to explore the possible mechanism of floral organ variation. Methods: Five, six, and seven petals of single-flower gardenia were selected as test materials for transcriptome and metabolome determination to excavate the key genes in regulating petal number in gardenia. Results: Metabolomic analysis identified triethylamine, succinic acid, succinylaldehyde, 2-phenylethanol, and o-xylene as the top five differentially expressed metabolites affecting petal number variation in gardenia. In the KEGG enrichment analysis, gardenia five, six, and seven DEGs were mainly enriched in amphetamine biosynthesis, the biosynthesis of plant secondary metabolites; transcriptome results showed that the identified differential transcription factors mainly come from NAC, ERF, C2H2, MYB, and MADS-box gene families; the expression of GjMADS50, GjMADS59, and GjERF28 changed with the increase in petal number. The commonality between gardenia five, six, and seven flowers exceeded the difference, and the expression pattern of MADS-box and ERF gene family members was the upregulation of GjERF28, GjERF39, and GjMADS67 and downregulation of GjMADS50, GjMADS59, and GjMADS60. Conclusions: We propose that ERF transcription factors may determine the initial number of petal primordia by mediating gibberellin biosynthesis or signaling, thereby coordinately regulating floral meristem activity and specific metabolic states. Full article

Background: The Camellia genus is widely recognized for its remarkable diversity in floral morphology and coloration, with Camellia petelotii (Merr.) Sealy being particularly notable for its rare golden-yellow flowers, which possess exceptional ornamental value. Despite its horticultural significance, the molecular mechanisms governing its flowering process remain poorly elucidated, presenting a substantial barrier to effective conservation and breeding initiatives. Methods: To address this knowledge gap, we conducted a comprehensive transcriptomic analysis, focusing on three distinct developmental stages of C. petelotii floral organs: the alabastrum stage (S1), the half-opened flower stage (S2), and the full bloom stage (S3). These samples were subjected to high-throughput sequencing using the Illumina platform. Following rigorous quality control and alignment with the reference genome, we performed transcript assembly and integrated comprehensive gene annotation data with quantitative gene expression profiles. Results: Our analysis identified 18,732 differentially expressed genes (DEGs) showing significant expression changes across developmental stages. Notably, we identified 134 DEGs as potential flowering-related genes, which were functionally associated with key pathways involved in floral regulation, including plant hormone signal transduction (e.g., AUX/IAA, ARF, SAUR, GH3, JAR4, GID1 and SOC1), starch (SS, SUS, BAM) and sucrose metabolism (HK, FrK, and GH32), circadian rhythm regulation (e.g., PIF3, ELF3, LHY, and PRR), and the Autonomous pathway. Building upon these findings, we have proposed a comprehensive model illustrating the regulatory network underlying flowering transition in C. petelotii. The reliability of the transcriptomic data was demonstrated through the validation of 11 genes using quantitative real-time PCR (qRT-PCR). Conclusions: These insights not only enhance our understanding of the molecular basis of flowering in this species but also provide a valuable theoretical framework for future genetic improvement and breeding programs of C. petelotii. Full article

Cauliflower (Brassica oleracea var. botrytis) curd formation is a highly complex developmental process governed by tightly coordinated genetic and physiological regulation. Here, we performed transcriptome sequencing of curd and peduncle tissues across multiple developmental stages, generating 171.52 Gb of high-quality data. Genes associated with photosynthesis and glucosinolate biosynthesis were strongly upregulated in the shoot apical meristem (SAM), highlighting substantial metabolic investment during the pre-initiation phase of curd morphogenesis. Key floral transition regulators, particularly AP2 and MADS-box transcription factors, were activated to drive the vegetative-to-reproductive switch and initiate curd primordia, ultimately giving rise to the arrested inflorescence architecture characteristic of cauliflower. Furthermore, hormone signaling pathways—including auxin (AUX), jasmonic acid (JA), and brassinosteroid (BR)—showed marked activation during SAM proliferation and peduncle elongation, underscoring their crucial roles in structural patterning. Collectively, our findings delineate an integrated regulatory network that links metabolic activity, hormone signaling, and developmental programs, providing novel molecular insights into curd formation and identifying potential breeding targets for the genetic improvement of Brassicaceae crops. Full article

The Archaic period in the Maya lowlands of Mesoamerica emerged around 8000 BCE and likely lasted until about 1000 BCE; however, both the development and complex cultural adaptations representative of Archaic peoples present challenges for archaeologists. In central Belize, archaeological evidence for Archaic people is limited, especially when compared to northern and southern Belize. Nevertheless, our knowledge of Archaic lifestyles in this part of the world has substantially increased over the last twenty years or so. This paper reviews the current understanding of the Archaic period in central Belize based primarily on radiocarbon dates from stratigraphic excavations, diagnostic lithic artifacts, and both faunal and floral remains recovered from excavations, and compares these data to archaeological evidence from northern and southern Belize for regional contextualization and synthesis. Although some aspects of Archaic lifestyles in central Belize appear quite clear based on the available archaeological evidence, others remain elusive. More regional surveys to find sites and an increased number of excavations with datable stratigraphic contexts are needed to more accurately reconstruct the lives of the people who initially inhabited central Belize prior to the emergence of the first culturally recognizable Maya. Full article

This study comprehensively characterizes the PEBP gene family in Cymbidium sinense, an orchid with a prolonged vegetative phase that limits its industrial production. Genome-wide analysis identified six CsPEBPs, classified into FT-like, TFL1-like, and MFT-like subfamilies. Evolutionary, gene structure, and collinearity analyses revealed both conservation and lineage-specific diversification of these genes. CsFTL3, a distinctive FT-like member, displayed notably high expression during the bud undifferentiated stage, followed by a sharp downregulation upon floral initiation. Functional studies identified CsFTL3 as a key floral repressor. Heterologous overexpression in Arabidopsis delayed flowering time from 32.0 days (wild-type) to 63.0–75.3 days (transgenic) and increased rosette leaf number from 12.6 to 33.0–34.5, while its knockdown via virus-induced gene silencing (VIGS) in C. sinense accelerated floral bud development and upregulated flowering-promoter genes. Phylogenetically, CsFTL3 falls within the flowering repressor FT-I clade, and multiple sequence alignment identified critical amino acid substitutions (Y134S, W138L, Q140E) that likely underpin its functional divergence from typical flowering promoters. Furthermore, promoter analysis revealed an enrichment of light-, hormone-, and stress-responsive cis-elements, and its expression was modulated by gibberellin (GA), abscisic acid (ABA), and low-temperature treatments. Predicted protein–protein interaction and transcriptional regulatory networks provide preliminary insights into its complex regulation. We conclude that CsFTL3 acts as a crucial floral inhibitor, integrating environmental and endogenous cues to repress flowering. These findings offer fundamental insights into the molecular mechanisms of flowering in orchids and provide a valuable genetic resource for molecular breeding programs aimed at achieving precise flowering time control. Full article

Forests are important biodiversity reservoirs and require sustainable management to prevent deforestation and forest degradation. Forest landscape restoration (FLR) has been proposed as a sustainable initiative aimed at restoring ecosystem functions and improving the well-being of surrounding populations. In 2005, the World Wildlife Fund (WWF) initiated a project to protect 200 ha of savanna in Manzonzi landscape, Democratic Republic of Congo, on the outskirts of the Luki Biosphere Reserve. The biodiversity changes related to this ecological restoration project remain unpublished. To address this knowledge gap, floristic inventories of the protected Manzonzi landscape were carried out over a 12-year period and we assessed how changes in the floral composition of this landscape evolved and affected the provision of ecosystem services (ES). We found that protection of the savanna by banning recurring bush fires and fencing off the area promoted the richness and abundance of forest species, such as Xylopia aethiopica (Dunal) A. Rich, Albizia adianthifolia (Schumach.) W. Wight. These forest taxa replaced grassland species, such as Hymenocardia acida Tul. and Maprounea africana Müll. Arg., and served to benefit the local population, who use these forest taxa as food, fuelwood, and medicines. This study revealed that protected savanna improved woody biomass, plant diversity (richness/abundance), and carbon storage, significantly boosting essential ES for communities; yet these positive trends reversed when active monitoring ceased. Protecting savannas improves the environment and benefits communities, but stopping protection efforts can undo these gains, emphasizing the need for ongoing conservation. Full article

Pile fermentation is a crucial process for developing the characteristic mellow taste and aged aroma of dark tea, yet the internal quality transformation mechanism of this process is still unclear. This study employed a high-sensitivity analytical platform based on gas chromatography–mass spectrometry (GC-MS) to systematically investigate the dynamic interplay between key chemical components, enzyme activities, and volatile compounds during the pile fermentation of primary dark tea. Our findings revealed a significant decrease in ester-type catechins, crude protein, and protopectin, alongside a notable accumulation of non-ester-type catechins, gallic acid, and soluble components. The multi-enzyme system—comprising PPO/POD, pectinase/cellulase, and protease—cooperatively drove the oxidation of phenols, cell wall degradation, and the release of aromatic precursors. This was complemented by GC-MS analysis, which identified and quantified 103 volatile compounds across nine chemical classes. The total content of volatile compounds increased significantly, with alcohols, esters, and aldehydes/ketones being the dominant groups. Floral and fruity compounds such as linalool and geraniol accumulated continuously, while esters exhibited an initial increase followed by a decrease. Notably, carotenoid degradation products, including β-ionone, were significantly enriched during the later stages. This study revealed a “oxidation–hydrolysis–reconstruction” metabolic mechanism co-driven by microbial activity and a multi-enzyme system, providing a theoretical foundation for the precise regulation of pile fermentation and targeted quality improvement of primary dark tea. Full article

Angiosperms include many taxa with dimorphic unisexual reproductive structures. These are well studied in some grasses, with maize as a key model, but other wind-pollinated lineages in Poales remain less explored. Within Poales, the family Restionaceae has the highest known proportion of dioecious species. In its Australian subfamily Leptocarpoideae, the sexually dimorphic Leptocarpus denmarkicus has raised questions about the basic flowering unit and the developmental basis of dimorphism. Here, we analyze inflorescence architecture and floral development in Eurychorda complanata, the sister lineage to the remainder of Leptocarpoideae. Using comparative morphology, light microscopy and scanning electron microscopy, we reconstruct synflorescence topology, floral organography, and ontogeny in both sexes and compare them with those in L. denmarkicus. In Eurychorda, both sexes produce polytelic paniculate synflorescences with distinct inhibition zones and many-flowered simple spikelets as the basic flowering unit. Male and female spikelets bear up to 50 and up to 15 fertile flowers, respectively. Male flowers have two stamens and a dimerous pistillode, whereas female flowers possess two long filamentous staminodes and a dimerous gynoecium. Ontogenetic series show that flowers of both sexes initiate both androecial and gynoecial structures, and that functional unisexuality is achieved through late arrest of the organs of one sex. Defining spikelets as racemose axes with lateral sessile flowers clarifies homologies of reproductive structures and supports reinterpretation of the dimorphic female unit in L. denmarkicus as a derived compound spike generated through shifts in branching rank and the timing of lateral initiation. The compound female spike of L. denmarkicus has a striking overall similarity to the simple female spikelet in Eurychorda, illustrating fascinating parallelism in the evolution of reproductive organs within Restionaceae and Poales more broadly. At the male side, Eurychorda achieves anther exsertion via filament elongation, whereas in L. denmarkicus filaments are very short and anthers remain within the perianth, but male spikelets sit on long, flexible peduncles that invert the spikelet and promote trembling, thereby ventilating the perianth chamber and aiding pollen escape. These two solutions—filament elongation versus spikelet-peduncle flexibility—represent alternative strategies of pollen release in wind-pollinated flowers. Full article

Fruit production in passionfruit species is primarily associated with cross-pollination, but the role of herkogamy, the spatial separation between stigmas and anthers, in reproductive success remains poorly understood. This study evaluated the influence of style deflexion on fruit set in Passiflora cincinnata Mast., a native species of the Brazilian Caatinga, using accessions conserved in a Passionfruit Germplasm Bank (BAG). Flowers were classified into three morphotypes: stigmas positioned below the anthers, stigmas aligned with the anthers, and stigmas positioned above the anthers. Pollen viability was evaluated using subsamples of randomly selected flowers within each floral morphotype. Across all accessions, 41.75% of flowers displayed stigma below the anthers, 26.32% exhibited aligned the stigma with the anthers, and 31.93% had stigma positioned above, with pollen viability consistently high (96.4–96.7%). Flowers in which stigmas were located below the anthers (negative deflexion) showed the highest fruit set under hand pollination (73.3%), whereas flowers with aligned or elevated stigmas produced only a few fruits (4.7%) in heterotypic crosses. These findings demonstrated that herkogamy strongly shapes reproductive outcomes in P. cincinnata. Integrating this knowledge into germplasm management, conservation, and breeding initiatives will be essential for improving passionfruit cultivation and promoting sustainable agricultural practices in semiarid ecosystems. Full article