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Corolla

In botany, the corolla is the collective term for the petals of a flower, forming the inner whorl of the perianth (the non-reproductive outer parts). Typically brightly colored or white, the corolla attracts pollinators such as insects and birds, while also protecting the reproductive organs.^[1] Positioned inside the calyx (sepals), the corolla surrounds the stamens and pistils. Petals may be fused or separate, varying in number and arrangement across angiosperm species, contributing to floral diversity and evolutionary adaptations.^[1]

Definition and Anatomy

Basic Definition

The corolla is the whorl of petals in a flower, collectively forming the inner perianth and typically located inside the calyx.^[2] It consists of modified leaves that are often colorful and serve as a visual display.^[3] The term "corolla" derives from the Latin word meaning "small crown" or "garland," a usage introduced in botany by Carl Linnaeus in his 1736 work Fundamenta Botanica to evoke the structure's crown-like arrangement around the flower's center.^[4] In contrast to the calyx, which comprises green, protective sepals, the corolla is petal-based, frequently showy, and positioned inward to enclose the reproductive organs in the bud stage.^[5] In some monocots, the perianth may be undifferentiated, with corolla and calyx segments appearing similar as tepals.^[6]

Structural Components

The corolla is composed of one or more petals, which are the individual units forming this floral whorl.^[7] Petals are typically thin, blade-like structures consisting of a broadened upper portion known as the lamina or blade and a narrower basal portion called the claw.^[8] The lamina provides the expanded surface, while the claw serves as the attachment point for the petal.^[9] Petals are attached to the receptacle or, in some cases, the hypanthium via the claw at the base of the flower.^[10] These attachments often feature distinctive venation patterns that radiate from the base, supporting the petal's structure.^[11] Nectar guides, appearing as contrasting color patterns or markings on the lamina, are common structural elements on many petals.^[12] In eudicots, the corolla usually consists of four or five petals, though multiples of these numbers occur in some lineages.^[13] Monocots exhibit more variability, often with three petals or multiples thereof.^[14] Petals may be arranged in a regular (actinomorphic) pattern, allowing division into mirror-image halves along any plane through the center, or an irregular (zygomorphic) pattern, divisible into mirror images along only one plane.^[15] The calyx forms the outer whorl beneath the corolla.^[16]

Relation to Other Floral Parts

The corolla forms the inner whorl of the perianth, positioned immediately above the calyx on the floral receptacle and below the androecium and gynoecium, thereby enclosing or surrounding the reproductive organs of the flower.^[17]^[18] This arrangement places the corolla in direct structural continuity with the outer sepals, collectively comprising the non-reproductive envelope known as the perianth.^[7] In terms of interactions, the corolla often overlaps with or fuses to the sepals, especially in cases of perianth fusion, creating a unified protective layer around the inner floral elements.^[18] Its proximity to the stamens of the androecium positions the corolla to frame the pollen-bearing structures, while the overall whorl configuration allows it to enclose the ovary of the gynoecium in typical complete flowers.^[19]^[7] In incomplete flowers, the corolla is frequently reduced, modified, or entirely absent, as seen in many wind-pollinated species such as corn (Zea mays), where the lack of a showy perianth eliminates the need for such structures.^[7]^[18]

Functions

Role in Pollination

The corolla plays a central role in pollination by serving as the primary floral structure for attracting pollinators and guiding them to reproductive organs. Through its vibrant colors, scents, and morphological features, the corolla enhances the efficiency of pollen transfer in angiosperms, promoting cross-pollination between plants.^[20]^[21] Attraction mechanisms of the corolla include conspicuous colors that target specific pollinators based on their visual capabilities. For instance, red or yellow corollas appeal to birds like hummingbirds, while blue or ultraviolet-reflective patterns attract bees, which perceive ultraviolet light.^[20]^[21] Scent production from corolla tissues further draws in nocturnal pollinators such as moths and bats, often combining with pale or white coloration for visibility in low light.^[20]^[22] These traits collectively signal the availability of rewards like nectar and pollen, increasing visitation rates.^[23] Guidance features ensure precise pollinator behavior during visits. Nectar guides—often ultraviolet patterns or contrasting markings on petals—direct pollinators toward the flower's center, where nectar and pollen are located, minimizing wasted effort and maximizing pollen deposition.^[20]^[21] Landing platforms formed by broad, flat petals provide stable surfaces for insects like bees and butterflies to alight, facilitating contact with anthers and stigmas.^[22]^[21] Specialized shapes, such as elongated tubes or spurs in the corolla, accommodate long-tongued pollinators, channeling their proboscises to essential floral parts.^[22]^[21] Pollination syndromes illustrate how corolla traits correlate with particular pollinators, reflecting co-evolutionary adaptations. Bee-pollinated flowers often feature open corollas in yellows or blues with prominent nectar guides, as seen in sunflowers.^[21] Bird-pollinated syndromes include bright red, tubular corollas, exemplified by scarlet beebalm visited by hummingbirds.^[20]^[21] Moth-pollinated flowers typically have white, nocturnal blooms with strong scents and deep nectar tubes, such as in certain columbines.^[21] Bat-pollinated corollas are large, pale, and strongly scented, providing sturdy landing areas for these mammals.^[22]^[21] These syndromes enhance pollination success by aligning floral design with pollinator morphology and behavior.^[23]

Protective and Attractive Features

The corolla serves protective functions during the flower bud stage by enclosing and shielding the developing reproductive organs from environmental stresses such as ultraviolet (UV) radiation, desiccation, and herbivory, often in conjunction with the calyx. UV-absorbing pigments in the petals, such as flavonoids, absorb harmful UV light to safeguard pollen and ovules from radiation damage, particularly in exposed habitats. Additionally, the compact structure of the corolla in buds helps maintain internal humidity, reducing water loss and preventing desiccation of sensitive inner tissues. The layered petals also act as a physical barrier against small herbivores and pathogens, minimizing damage to immature floral parts. Post-anthesis, the wilting of the corolla contributes to protection by effectively closing the flower, which limits further exposure to desiccation and herbivore access while conserving plant resources for seed development. In many species, this senescence response is triggered after pollination, leading to rapid petal closure that reduces vulnerability to environmental extremes and opportunistic feeders. By sealing the flower, wilting minimizes the risk of secondary infections or excessive moisture loss in humid conditions. Beyond direct pollination cues, the corolla exhibits attractive diversity through patterns and traits that enhance visibility to pollinators in varied environments. UV-reflective or absorbing markings on petals, often forming "bullseyes" or guides invisible to the human eye but detectable by insects via UV vision, draw pollinators effectively while providing incidental protection by absorbing excess radiation. Variations in corolla size, such as larger petals in windy or open habitats, increase aerodynamic stability and visual prominence, while textured surfaces like papillose cells improve light scattering for better attraction in low-light understories. The corolla's ephemeral nature, typically lasting only a few days after anthesis, represents an adaptive strategy to balance attraction duration with energy efficiency. This short lifespan minimizes the metabolic costs of maintaining colorful, nectar-producing structures, allowing plants to allocate resources toward fruit and seed production once pollination occurs. In resource-limited environments, such transient displays optimize reproductive success by reducing the trade-off between floral maintenance and overall plant fitness.

Developmental Functions

The corolla develops from the second whorl of the floral meristem in angiosperms, where petal primordia initiate shortly after sepal primordia emerge from the peripheral zone of the meristem. These primordia arise through localized cell proliferation and outgrowth, establishing the foundational structure of the petals that collectively form the corolla. Petal identity is specified by the ABC model of flower development, a combinatorial genetic framework in which A-class genes (such as APETALA1) and B-class genes (such as APETALA3 and PISTILLATA) act together to promote petal formation while repressing other organ identities.^[24] This model, first elucidated in model species like Arabidopsis thaliana and Antirrhinum majus, ensures that the corolla differentiates distinctly from sepals and stamens.^[24] As the flower progresses toward anthesis, corolla maturation involves rapid expansion driven by a biphasic pattern of cell division followed by extensive cell elongation and vacuolar growth, which unfolds the petals and increases corolla size by several-fold in species like carnations.^[25] During this phase, the initially green corolla, resulting from chlorophyll accumulation in young petals, undergoes color transition as chlorophyll degrades and secondary pigments such as anthocyanins or carotenoids accumulate in the epidermal cells, enhancing visual appeal for pollinators.^[26] This pigmentation shift is regulated by developmental cues including hormonal signals like auxin, which coordinate pigment biosynthesis genes.^[27] Senescence signaling begins subtly during late maturation, with ethylene and other hormones priming cells for eventual breakdown, though full wilting typically follows pollination.^[27] Resource allocation to corolla development represents a significant energetic investment by the plant to support pollinator attraction prior to fertilization. Post-pollination, programmed cell death (PCD) in corolla tissues is triggered via ethylene-dependent pathways, leading to proteolysis, nucleic acid degradation, and nutrient remobilization from petals to support seed and fruit development.^[28] This PCD process, observed in petunias and other model flowers, ensures efficient resource recycling, minimizing post-reproductive costs and enhancing overall fitness.^[28] The corolla's developmental trajectory is briefly coordinated with adjacent whorls through shared meristematic signals, maintaining overall floral architecture.^[24]

Morphological Variations

Petal Fusion Types

The corolla exhibits variation in petal fusion, a fundamental morphological trait that distinguishes major types within angiosperm flowers. Petals may remain entirely separate or adhere to varying degrees, influencing the overall structure of the corolla.^[29] In a polypetalous corolla, also termed apopetalous or choripetalous, the petals are free and distinct from one another, allowing independent movement and flexibility in the flower's appearance. This condition is characteristic of families such as Rosaceae, where roses (Rosa spp.) display five separate, often white or pink petals arranged in a rosaceous pattern.^[29]^[30] Conversely, a gamopetalous corolla, synonymous with sympetalous, features petals that are fused at least partially, typically forming cohesive structures such as tubes, funnels, or bells that unify the petal whorl. This fusion is prevalent in the Solanaceae family, exemplified by tomatoes (Solanum lycopersicum), whose corolla consists of five united petals creating a rotate or wheel-like form.^[29]^[31]^[32] The extent of fusion in gamopetalous corollas ranges from partial adhesion, where petals join only at the base, to complete cohesion forming a continuous tube or urn, as seen in varying shapes across species; this gradation, from sympetalous bases to fully enclosed forms, contributes to structural diversity and specificity in floral architecture.^[33]^[29] Aestivation patterns complement these fusion types by describing petal arrangements in the bud stage.^[29]

Aestivation Patterns

Aestivation refers to the specific arrangement and folding of petals within the unopened flower bud, which determines the sequence and manner in which the corolla unfolds during anthesis.^[34] This pre-anthesis configuration is distinct from mature petal fusion and influences the mechanics of bud expansion without altering the final floral symmetry.^[34] Valvate aestivation occurs when the margins of adjacent petals simply touch each other along their edges without any overlapping, resulting in a compact bud where petals are aligned edge-to-edge.^[35] This pattern is characteristic of the Brassicaceae family, such as in mustard flowers, where the four petals meet valvatelly to enclose the reproductive organs efficiently.^[36] Imbricate aestivation involves petals that overlap one another in a tile-like fashion, with each petal's margin overlapping the adjacent one to provide a more secure enclosure of the bud.^[34] Subtypes include vexillary aestivation, prevalent in the Fabaceae (legume) family, where the posterior standard petal overlaps the two wing petals, which in turn overlap the anterior keel petals, forming a papilionaceous structure that protects the bud while facilitating targeted pollination.^[37] Another subtype is quincuncial aestivation, typically seen in pentamerous corollas, where two petals are interior, two are exterior, and the fifth overlaps both margins of its neighbors, creating an asymmetrical overlap that ensures orderly unfolding.^[38] Contorted or twisted aestivation features petals that are coiled or overlap in a helical manner, with each petal's margin overlapping the next in a consistent direction, often right- or left-handed.^[34] This pattern is common in gamopetalous corollas, such as those in the Convolvulaceae family (morning glories), where the fused petals twist tightly in the bud to compactly house the stamens and pistil before uncoiling at maturity.^[39]

Symmetry and Shape Diversity

The corolla displays two fundamental symmetries that influence floral architecture and pollinator interactions. Actinomorphic symmetry, also known as radial symmetry, allows the corolla to be divided into identical halves by three or more vertical planes through the center, resulting in uniform petal arrangements that facilitate access by diverse generalist pollinators such as various insects. This symmetry is prevalent in the disk florets of Asteraceae, where the corolla supports broad pollination strategies in open habitats.^[40]^[41] Zygomorphic symmetry, or bilateral symmetry, permits division into mirror-image halves along a single vertical plane, creating directional structures that guide specialist pollinators for precise pollen transfer. This form enhances specificity in pollination syndromes and is characteristic of Orchidaceae, where intricate corolla configurations mimic pollinator preferences or mating signals.^[40]^[42] Corolla shapes further diversify floral architecture, adapting to ecological niches across angiosperm families. Common forms include rotate (flat and wheel-like, with a short tube and spreading limb), campanulate (bell-shaped, widening from a narrow base), tubular (cylindrical and elongated), and ligulate (strap-like, with a flattened extension). For example, rotate shapes occur in Solanaceae, campanulate in Campanulaceae, tubular in many disk florets of Asteraceae, and ligulate in ray florets of Asteraceae, each contributing to visual appeal and functional efficiency in pollination. The mature shape often reflects aestivation patterns established during bud development.^[43]

Evolutionary and Genetic Aspects

Evolutionary Origins

The corolla, comprising the whorl of petals in angiosperm flowers, traces its evolutionary precursors to structures in gymnosperms, where sterile bracts subtending reproductive organs likely served as foundational elements. In gymnosperms such as Bennettitales and some conifers, these bracts formed protective or attractive appendages around ovules and pollen-bearing structures, providing a morphological template for later perianth evolution without true floral differentiation.^[44]^[18] The emergence of the corolla proper occurred with the radiation of angiosperms, whose crown group origin estimates range from 202–255 million years ago during the Triassic or Late Permian, based on recent molecular clock analyses calibrated against fossil data.^[45] This timeline aligns with the diversification of early flowering plants, marking a shift from gymnosperm-like reproductive systems to enclosed, more specialized floral organs.^[46]^[47] Fossil evidence from the Yixian Formation in China reveals some of the earliest angiosperm reproductive structures, including those of Archaefructus liaoningensis, dated to approximately 125 million years ago, which exhibit simple, elongated floral axes with carpels and stamens but lack a differentiated perianth; these rudimentary features represent transitional corolla-like configurations preceding more elaborate petal whorls. Subsequent Early Cretaceous fossils, such as those from Portugal and North America, show gradual perianth development with tepals that grade from sepaloid to petaloid forms, indicating the initial stages of corolla specialization.^[48]^[49] The elaboration of the corolla was driven by coevolution with animal pollinators, particularly insects, as early angiosperms transitioned from ancestral wind-pollination strategies prevalent in gymnosperms to biotic pollination modes that enhanced reproductive efficiency. This selective pressure favored colorful, scented petals for visual and olfactory attraction, contributing to the rapid diversification of floral forms in the Cretaceous.^[50]^[51]

Genetic Regulation

The genetic regulation of corolla formation in angiosperms is primarily governed by the ABC(DE) model of floral organ identity, which posits that combinatorial activity of specific gene classes determines the development of floral whorls. In this framework, the corolla, comprising petals in the second whorl, is specified by the activity of B-class genes in combination with A-class genes, while B-class genes alone with C-class genes specify stamens in the third whorl. The B-class genes, such as APETALA3 (AP3) and PISTILLATA (PI) in Arabidopsis thaliana, encode MADS-box transcription factors that form heterodimers essential for petal identity, with their expression initiating early in floral meristem development to promote petal primordia formation.^[52] Loss of AP3 or PI function results in the homeotic transformation of petals into sepals, underscoring their critical role in distinguishing the second whorl from the sepals of the first whorl.^[53] Regulatory networks controlling corolla development involve intricate interactions among MADS-box transcription factors, which act as key regulators by binding to DNA motifs and activating downstream targets involved in cell proliferation and differentiation within petal tissues. These factors, including AP3 and PI, form protein complexes that integrate signals for petal morphogenesis, such as regulating genes for cell wall modification and pigmentation.^[54] Hormonal influences, particularly auxin, further modulate these networks by promoting petal initiation through localized biosynthesis in the inter-sepal zones of the floral meristem, where auxin maxima guide primordia outgrowth and prevent ectopic organ formation.^[55] Auxin signaling interacts with MADS-box pathways to fine-tune corolla patterning, ensuring coordinated growth and symmetry. Recent studies as of 2025 have elucidated how hormone signaling, including auxin and cytokinin gradients, regulates cellular patterning in petals, contributing to microscale diversity in corolla evolution across angiosperms.^[56]^[57] Mutations in genes regulating corolla identity often manifest as homeotic alterations, where petals are converted to other floral organs, providing insights into the precision of genetic controls. For instance, in Arabidopsis ap3 mutants, the second whorl develops sepal-like structures instead of petals due to the absence of B-class activity, while pi mutants exhibit similar transformations, with additional effects on stamen identity in the third whorl. Such mutants highlight the dosage-dependent nature of B-class gene function, as partial loss-of-function alleles can produce intermediate phenotypes, such as petaloid stamens, revealing the underlying regulatory thresholds.^[53] These genetic perturbations not only disrupt corolla formation but also illustrate how evolutionary conservation of MADS-box networks maintains petal diversity across angiosperms.^[58]

Adaptations in Angiosperms

In angiosperms, corolla morphology exhibits significant environmental adaptations that align with pollination strategies and habitat conditions. In arid environments and wind-pollinated species, such as those in the Poaceae family, corollas are often reduced in size or absent to minimize water loss and energy expenditure, as these plants rely on anemophily rather than visual attractants for pollen dispersal.^[59] This reduction is a convergent trait across multiple lineages, facilitating efficient reproduction in resource-scarce settings where insect activity is limited by drought or low temperatures.^[60] Conversely, in tropical regions dominated by insect pollination, corollas tend to be enlarged and vividly colored to enhance visibility and appeal to diverse pollinators, promoting higher rates of cross-pollination in humid, biodiverse ecosystems.^[61] Family-specific adaptations further illustrate corolla specialization for particular pollinators. In the Lamiaceae family, elongated corolla tubes have evolved to accommodate bee proboscises, restricting nectar access to long-tongued species and thereby increasing pollination precision while protecting pollen from inefficient visitors.^[62] Similarly, in Asteraceae, ray florets—modified, strap-shaped corolla extensions—serve as visual lures to attract a broad array of insects, guiding them toward the central disc florets where reproduction occurs, thus amplifying floral display without additional fertile structures.^[63] These traits underscore how corolla architecture can evolve to match pollinator morphology and behavior within taxonomic groups. Recent studies from the 2020s highlight potential shifts in corolla traits driven by climate change and associated pollinator declines. As global warming disrupts pollinator populations and alters abiotic factors, selective pressures may favor smaller or less conspicuous corollas in some species to reduce maintenance costs amid reduced visitation, potentially leading to evolutionary mismatches in plant-pollinator interactions.^[64] Such changes could exacerbate biodiversity loss if corolla adaptations fail to keep pace with rapid environmental shifts. Genetic mechanisms, including regulatory genes influencing floral development, provide the underlying flexibility for these adaptive responses across angiosperm lineages.^[65]

Examples and Applications

Common Plant Examples

In eudicots, the rose (Rosa spp., family Rosaceae) exemplifies a polypetalous, actinomorphic corolla, consisting of five distinct, free petals arranged in radial symmetry around the floral axis.^[66] These petals are typically white, pink, or red, contributing to the flower's visual appeal. Another representative eudicot is the garden petunia (Petunia × hybrida, family Solanaceae), which displays a gamopetalous corolla forming a distinctive funnel-shaped or tubular structure with five fused petals that flare outward at the limb, often in vibrant shades of purple, pink, or white.^[67] Among monocots, the tulip (Tulipa spp., family Liliaceae) features a polypetalous, actinomorphic corolla composed of six colorful tepals functioning as petals, arranged in two whorls of three for a symmetrical display.^[68] The iris (Iris spp., family Iridaceae) presents a corolla-like perianth of six tepals with zygomorphic elements, including three upright inner tepals (standards) and three drooping outer tepals (falls) that introduce bilateral asymmetry while maintaining overall floral balance.^[68] Specialized corolla modifications occur in carnivorous plants such as the pitcher plant (Sarracenia spp., family Sarraceniaceae), where the corolla comprises five separate, wavy petals—typically yellow or red—that nod over the flower to enhance pollinator attraction in nutrient-poor habitats.^[69]

Botanical Significance

The corolla plays a pivotal role in the taxonomy of angiosperms, serving as a key morphological trait for identification and classification. Traits such as petal number, fusion (e.g., polypetalous vs. gamopetalous), and aestivation patterns are integral to dichotomous keys used in floral identification, enabling botanists to distinguish genera and families efficiently.^[70] In the Angiosperm Phylogeny Group (APG) IV system, which integrates molecular data with morphology, corolla characteristics contribute to family delimitation; for instance, the presence of a tubular or rotate corolla helps define orders like Asterales and Lamiales, supporting phylogenetic relationships among over 420 families. Ecologically, the corolla functions as a critical indicator of biodiversity within plant communities, reflecting adaptations to specific pollinator guilds and environmental pressures. Variations in corolla size and shape often correlate strongly with pollinator body size, promoting specialized interactions that enhance reproductive success; for example, deeper corolla tubes match longer proboscises in hawkmoths or hummingbirds, optimizing pollen transfer efficiency.^[71] Such correlations underscore the corolla's role in maintaining ecosystem stability, as shifts in pollinator populations due to habitat loss can alter corolla morphology over time, serving as a proxy for biodiversity health in monitoring programs.^[23] Despite these insights, significant research gaps persist in the molecular ecology of corollas, particularly in linking genetic mechanisms to ecological outcomes. Pre-2020 studies largely focused on basic developmental pathways, but recent CRISPR/Cas9 applications have begun addressing these by editing genes like ATG6 in petunia, revealing how autophagy influences corolla longevity and resource allocation under stress.^[72] These post-2020 advancements highlight the need for integrated studies combining CRISPR-edited models with field ecology to fully elucidate corolla responses to climate change, an area still underexplored relative to evolutionary origins. Recent 2023–2025 research has further advanced this field, including CRISPR/Cas9 editing for anthocyanin regulation in flower color change and NAC transcription factors in floral senescence for extended corolla longevity in species like carnations.^[73]^[74]^[75]

Human Uses and Symbolism

In horticulture, selective breeding targets corolla traits to enhance ornamental value, particularly color diversity and petal durability in species like roses (Rosa spp.). Breeders evaluate germplasm for flower color, identifying up to 11 distinct types—including white, yellow, pink, red, and blue-violet—across 192 rose genotypes, with modern cultivars exhibiting the broadest range due to pigmentation from anthocyanins, flavonols, and carotenoids.^[76] Genetic engineering further expands corolla coloration; for instance, introducing the flavonoid 3′5′-hydroxylase (F3′5′H) gene into roses produces delphinidin-based anthocyanins, yielding commercial violet varieties like the Suntory blue rose Applause, though true blue remains challenging due to vacuolar pH constraints.^[77] The cut flower industry relies on corolla durability for extended vase life, a key economic factor influencing postharvest quality in species such as roses and chrysanthemums. Vase life, often measured by floret diameter, petal wilting resistance, and fresh weight retention, averages 7–14 days in untreated roses but can extend to 20+ days with preservatives like hydroxyquinoline sulfate, preserving corolla integrity for market transport and consumer appeal.^[78] Breeding programs prioritize robust corollas to minimize senescence, supporting an industry with domestic production valued at nearly $763 million in 2022.^[79] Corollas hold rich symbolism in human culture, often representing love, purity, and transience through their petals. In literature and art, petals evoke romantic uncertainty, as in the 15th-century European game "he loves me, he loves me not," where daisy corolla petals are plucked alternately to predict affection, a motif appearing in works like Shakespeare's A Midsummer Night's Dream to symbolize fleeting emotions.^[80]^[81] Floral motifs in heraldry further embed corolla symbolism; the rose, with its five-petaled corolla, signifies beauty, hope, and joy in English and Scottish arms, often depicted slipped and leaved as a charge dating to early medieval periods.^[82] Economically, corolla extracts contribute to industries like perfumery and dyes, while their traits influence agricultural pollination. Rose petals (Rosa damascena and related species) yield essential oils rich in citronellol and geraniol, comprising over 90% of global rose oil production from Bulgaria, Turkey, and Iran, used in high-value perfumes and cosmetics.^[83] Historically, petals from flowers like safflower and roses provided natural dyes for textiles, yielding yellows and pinks through extraction processes documented in ancient Egyptian and Persian practices.^[84] In agriculture, corolla color and shape attract pollinators that contribute to approximately 35% of global food production, with traits like vibrant hues boosting visitation and yields in pollinator-dependent species such as almonds and sunflowers.^[85]^[86]

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Dec 3, 2014 · The loss of chlorophylls during petal development is an important trait for flowering plants that enables flowers to be visually distinguished ...Results · Chlorophyll Content In... · Chlorophyll CycleMissing: corolla maturation
[30]
Transcriptome profiling reveals regulatory mechanisms underlying ...
Apr 1, 2018 · Our data suggest that hormonal interaction between auxin and ethylene may play critical regulatory roles in the onset of natural corolla senescence in petunia.Missing: maturation | Show results with:maturation
[31]
Programmed Cell Death during Pollination-Induced Petal ...
Petal senescence, one type of programmed cell death (PCD) in plants, is a genetically controlled sequence of events comprising its final developmental stage.
[32]
Corolla and its Forms: An Overview (With Diagrams) | Flower
It is polypetalous or dialypetalous if the petals are free from one another and gamopetalous or sympetalous if there is any degree of cohesion. When united ...
[33]
The Families of Flowering Plants - Rosaceae L.
Corolla when present, (3–)5(–10); 1 whorled; polypetalous; usually imbricate; regular; white, or yellow, or red, or pink (but not blue). Androecium (1–)10 ...
[34]
Solanaceae Juss. | Plants of the World Online | Kew Science
Corolla gamopetalous, usually 5-lobed, lobes folded, contorted or valvate ... A number of references to works concerning Solanum can be found at Solanaceae ...
[35]
Solanaceae Family (Night Shade or Potato Family) - Microbe Notes
Mar 16, 2024 · Calyx consists of five sepals, gamosepalous, persistant and often enlarged in fruit. Corolla consists of five petals, gamopetalous, and of ...
[36]
Corolla - What, Shapes, Fusion | Flower | Botany - BrainKart
May 1, 2018 · Fusion: a. Apopetalous (polypetalous, choripetalous): Petals are distinct. Example: Hibiscus. b. Sympetalous (gamopetalous): Petals are fused.
[37]
Symmetry in Flowers: Diversity and Evolution
It seems perhaps paradoxical that contort aestivation is the most symmetrical of all imbricate patterns in pentamerous flowers. Contort petal aestivation ...
[38]
[PDF] Plant Systematics Laboratory Manual
This manual covers plant systematics, including phylogenetic systematics, evolution, plant morphology, anatomy, embryology, palynology, and plant ...
[39]
[PDF] Brassicaceae Floral Formula
Aestivation. Valvate aestivation. Twisted aestivation. Imbricate aestivation. Vexillary aestivation. Aestivation : Memory trick. Androecium. Structure of Stamen.
[40]
Floral Evolution in the Detarieae (Leguminosae): Phylogenetic ...
Premise of research. We examine floral evolution and phylogenetic relationships in the monophyletic Detarieae and related lineages of Caesalpinioideae.
[41]
[PDF] Angiosperm family pairs: preliminary phylogenetic analyses
However, of the postulated synapomorphies. (listed above) it has only an infundibular, contorted corolla. ... PETALS: imbricate (0), valvate (just before anthesis) ...
[42]
[PDF] Lianas and Climbing Plants of the Neotropics: Convolvulaceae
Unique features: Robust herbaceous twining vines (rarely lianas) with white or watery sap; leaves alternate, commonly 5- to 7-palmately compound or lobed; ...
[43]
Floral symmetry: the geometry of plant reproduction - PMC
Aug 22, 2022 · In this review, we introduce the diversity of flower symmetry, trace its evolution in angiosperms, and highlight the conserved genetic basis underpinning ...
[44]
Patterns of Symmetry Expression in Angiosperms - Frontiers
Apr 27, 2020 · The corolla symmetry in anthetic flowers was identified as zygomorphic (79 species) or actinomorphic (148 species) based on the available ...
[45]
“What is a flower?” 6. The evo-devo of floral symmetry
Sep 8, 2017 · Two main types of symmetry are encountered in flowers: radial symmetry or actinomorphy (also called polysymmetry), and bilateral symmetry or ...
[46]
Corolla Types: 13 Main Types of Corolla (With Diagram)
It is irregular, polypetalous corolla with its five petals arranged so as to resemble a butterfly. It consists of a posterior largest 'vexillurri, two lateral ' ...
[47]
Are Petals Sterile Stamens or Bracts? The Origin and Evolution of ...
Although petals appear to have a bract origin in the core eudicots, it is not known whether the transition between tepals and petals occurred once or several ...
[48]
Origin and early evolution of angiosperms - PubMed
Molecular estimates of the age of crown group angiosperms have converged on 140-180 million years ago (Ma), older than the oldest fossils (132 Ma).
[49]
The ancestral flower of angiosperms and its early diversification
Aug 1, 2017 · The origin of the angiosperm flower remains among the most difficult and most important unresolved topics in evolutionary biology4,6,7,8,9,10,11 ...<|control11|><|separator|>
[50]
https://evolution-outreach.biomedcentral.com/articles/10.1007/s12052-009-0192-6
[51]
Diversity in obscurity: fossil flowers and the early history of ...
Newly discovered fossil flowers indicate considerable, previously unrecognized, cryptic diversity among the earliest angiosperms known from the fossil record.
[52]
Coevolution Between Food-Rewarding Flowers and Their Pollinators
Jan 13, 2010 · It is widely accepted that angiosperm flowers and their insect pollinators have influenced each other's evolution, but there is still ...
[53]
Pollinator-driven ecological speciation in plants: new evidence and ...
The hypothesis that pollinators have been important drivers of angiosperm diversity dates back to Darwin, and remains an important research topic today.
[54]
The Arabidopsis homeotic genes APETALA3 and PISTILLATA are ...
Jan 1, 1996 · The class B organ identity genes, APETALA3 and PISTILLATA, are required to specify petal and stamen identity in the Arabidopsis flower.
[55]
Function and regulation of the Arabidopsis floral homeotic gene ...
Mutations in the PISTILLATA (PI) gene of Arabidopsis thaliana cause homeotic conversion of petals to sepals and of stamens to carpels. It is thus classed as a B ...
[56]
Functional divergence within the APETALA3/PISTILLATA floral ...
The Arabidopsis thaliana AP3 and PI genes encode MIKC-type MADS domain-containing transcription factors and are required to specify petal and stamen identities ...
[57]
Auxin controls petal initiation in Arabidopsis | Development
Jan 1, 2013 · We have established that auxin is a direct and mobile petal initiation signal by promoting its biosynthesis in the inter-sepal zone in ptl mutant plants.
[58]
Auxin regulation of Arabidopsis flower development involves ...
During reproductive development, auxin specifies the site of flower initiation and subsequently regulates organ growth and patterning as well as later events ...Introduction · Auxin maxima specify the site... · Auxin regulates floral organ...
[59]
The ABC model of flower development: then and now
Nov 15, 2012 · The ABC model was popularized in a review in Nature published later in 1991 by the senior author and Enrico Coen, whose group had been making ...
[60]
[PDF] new perspectives on the evolution of wind pollination in angiosperms
Evolutionary transitions from animal to wind pollination have occurred repeatedly during the history of the angiosperms, but the selective mechanisms remain ...
[61]
Adaptive Radiation of Reproductive Characteristics in Angiosperms, I
Finally, the shift from insect to wind pollination is most likely to take place in regions where, either because of drought or cold, insects are scarce and the ...Missing: Poaceae | Show results with:Poaceae
[62]
Evolution of pollination syndromes and corolla symmetry in ...
Floral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator.
[63]
Bilabiate Flowers: The Ultimate Response to Bees? - PMC
Bilabiate blossoms protect their pollen against pollen-collecting bees and at the same time render their pollination more precisely.
[64]
Selective advantage of ray florets in Scalesia affinis and S ...
The presence of neuter ray florets in species within Asteraceae is generally believed to increase pollinator attraction. In the endemic Galápagos genus ...
[65]
The effect of global change on the expression and evolution of floral ...
Global change has depressed pollinator abundance and altered abiotic conditions, thereby exposing flowering plant species to novel suites of selective pressures ...
[66]
Corolla Monosymmetry: Evolution of a Morphological Novelty in the ...
Nov 30, 2011 · Monosymmetry evolved from a polysymmetric ancestor repeatedly in different angiosperm lineages, where it likely facilitated diversification ...
[67]
Rosaceae - Plant Systematics - Denison University
Jan 30, 2002 · corolla of 5 distinct petals, caducous; many whorls of stamen with ... medicinal Prunus (apricot seeds) and Rosa (rose hips); Perfumes ...
[68]
Petunia x hybrida - PlantFacts - The Ohio State University
... corolla that flares widely at its open end, with a slightly undulating margin and mild sweet fragrance; shades of purple, magenta, red, pink, violet, blue ...
[69]
[PDF] Field identification of the 50 most common plant families in ...
zygomorphic (rarely actinomorphic, A). ▫. Sepals 5, fused at base. ▫. Petals 5, fused at least at base (B). ▫. Stamens 2 or 4 (rarely 5), inserted into corolla ...
[70]
[Specimen details] / Plant Atlas - Atlas of Florida Plants - University ...
Pitcher plant [Sarracenia] ... Frequent; corolla yellow. Habitat, In depression in pine flatwoods. Reproductive State, Flower ... NW of Wilmer. Description, Flowers ...
[71]
[PDF] TAXONOMIC KEYS
• Taxonomic keys- used for identification of plant or animal. • Defined as ... corolla 1-2 mm long corolla 3-5mmlong. Page 8. Types of keys. • Dichotomous ...
[72]
Size‐matching as an important driver of plant‐pollinator interactions
Aug 7, 2025 · Our study revealed that foraging efficiency is maximal when bee proboscis length corresponds to the corolla tube depth of the flower visited.
[73]
CRISPR/Cas9-Mediated Editing of Autophagy Gene 6 in Petunia ...
Apr 26, 2022 · CRISPR/Cas9-Mediated Editing of Autophagy Gene 6 in Petunia Decreases Flower Longevity, Seed Yield, and Phosphorus Remobilization by ...
[74]
CRISPR/Cas9 System: A Potential Tool for Genetic Improvement in ...
Jun 25, 2022 · CRISPR/Cas9 gene editing could be useful in developing novel cultivars with higher fragrance and enhanced essential oil and many other useful traits.
[75]
Identification of distinct roses suitable for future breeding by ...
Jan 26, 2024 · The size of the flower corolla is the primary ornamental component in roses, significantly influencing the quality and economic value of cut ...
[76]
Recent advances in the research and development of blue flowers
Flower color is the most important trait in the breeding of ornamental plants. In the floriculture industry, however, bluish colored flowers of desirable plants ...
[77]
[PDF] Effects of Preservative Solutions on Vase Life and Postharvest ...
vase life and postharvest quality of rose cut flowers: Chlorophyll Determination: Chlorophyll content was. HQS at 200 ppm prolonged the vase life of rose cut.
[78]
https://www.idosi.org/aejaes/jaes13%281%2913/12.pdf
[79]
Bunches of Love: Flowers with Romantic Meanings - Beliefnet
It was during the 15th century that the hopelessly smitten started picking off petals to discover whether “he loves me/he loves me not” (the last petal to ...
[80]
https://www.beliefnet.com/love-family/galleries/bunches-of-love-flowers-with-romantic-meanings.aspx
[81]
flowers | Types - Mistholme
Jun 5, 2014 · The rose is a beautiful flower, the most frequently used flower in heraldry. It is also one of the oldest, dating from the earliest heraldry ...
[82]
[PDF] Rose Flowers—A Delicate Perfume or a Natural Healer?
Jan 19, 2021 · Roses are used for perfume, cosmetics, and have beneficial healing properties due to their components, and are used for treatment and ...
[83]
A review of history, properties, classification, applications and ...
Jul 15, 2024 · Plant-based dyes have a long history of use in various cultures for coloring textiles, crafts, and artworks. These dyes are sourced from ...
[84]
Importance of pollinators in changing landscapes for world crops
We found that pollinators are essential for 13 crops, production is highly pollinator dependent for 30, moderately for 27, slightly for 21, unimportant for 7.
[85]
Pollinators benefit economies | U.S. Fish & Wildlife Service
In the case of sunflowers, pollinators are economically important for seed production in an industry estimated at $10.4 million annually. Another example is the ...Pollinators Benefit... · Pollinators Improve Crops... · Pollinator Habitat Improves...