The garden strawberry is a grown hybrid species of the genus Fragaria, collectively known as the strawberries. It is cultivated worldwide for its fruit; the fruit is appreciated for its characteristic aroma, bright red color, juicy texture, sweetness. It is consumed in large quantities, either fresh or in such prepared foods as preserves, pies, ice creams and chocolates. Artificial strawberry flavorings and aromas are widely used in many products like lip gloss, hand sanitizers and many others; the garden strawberry was first bred in Brittany, France, in the 1750s via a cross of Fragaria virginiana from eastern North America and Fragaria chiloensis, brought from Chile by Amédée-François Frézier in 1714. Cultivars of Fragaria × ananassa have replaced, in commercial production, the woodland strawberry, the first strawberry species cultivated in the early 17th century; the strawberry is not, from a botanical point of view, a berry. Technically, it is an aggregate accessory fruit, meaning that the fleshy part is derived not from the plant's ovaries but from the receptacle that holds the ovaries.
Each apparent "seed" on the outside of the fruit is one of the ovaries of the flower, with a seed inside it. In 2016, world production of strawberries was 9.2 million tonnes, led by China with 41% of the total. The first garden strawberry was grown in Brittany, during the late 18th century. Prior to this, wild strawberries and cultivated selections from wild strawberry species were the common source of the fruit; the strawberry fruit was mentioned in ancient Roman literature in reference to its medicinal use. The French began taking the strawberry from the forest to their gardens for harvest in the 14th century. Charles V, France's king from 1364 to 1380, had 1,200 strawberry plants in his royal garden. In the early 15th century western European monks were using the wild strawberry in their illuminated manuscripts; the strawberry is found in Italian and German art, in English miniatures. The entire strawberry plant was used to treat depressive illnesses. By the 16th century, references of cultivation of the strawberry became more common.
People began using it for its supposed medicinal properties and botanists began naming the different species. In England the demand for regular strawberry farming had increased by the mid-16th century; the combination of strawberries and cream was created by Thomas Wolsey in the court of King Henry VIII. Instructions for growing and harvesting strawberries showed up in writing in 1578. By the end of the 16th century three European species had been cited: F. vesca, F. moschata, F. viridis. The garden strawberry was transplanted from the forests and the plants would be propagated asexually by cutting off the runners. Two subspecies of F. vesca were identified: F. sylvestris alba and F. sylvestris semperflorens. The introduction of F. virginiana from Eastern North America to Europe in the 17th century is an important part of history because this species gave rise to the modern strawberry. The new species spread through the continent and did not become appreciated until the end of the 18th century.
When a French excursion journeyed to Chile in 1712, it introduced the North American strawberry plant with female flowers that resulted in the common strawberry that we have today. The Mapuche and Huilliche Indians of Chile cultivated the female strawberry species until 1551, when the Spanish came to conquer the land. In 1765, a European explorer recorded the cultivation of the Chilean strawberry. At first introduction to Europe, the plants produced no fruit, it was discovered in 1766 that the female plants could only be pollinated by plants that produced large fruit: F. moschata, F. virginiana, F. ananassa. This is when the Europeans became aware that plants had the ability to produce male-only or female-only flowers; as more large-fruit producing plants were cultivated the Chilean strawberry decreased in population in Europe, except for around Brest where the Chilean strawberry thrived. The decline of the Chilean strawberry was caused by F. ananassa. Strawberry cultivars vary in size, flavor, degree of fertility, season of ripening, liability to disease and constitution of plant.
On average, a strawberry has about 200 seeds on its external membrane. Some vary in foliage, some vary materially in the relative development of their sexual organs. In most cases, the flowers appear hermaphroditic in structure, but function as either male or female. For purposes of commercial production, plants are propagated from runners and, in general, distributed as either bare root plants or plugs. Cultivation follows one of two general models—annual plasticulture, or a perennial system of matted rows or mounds. Greenhouses produce a small amount of strawberries during the off season; the bulk of modern commercial production uses the plasticulture system. In this method, raised beds are formed each year and covered with plastic to prevent weed growth and erosion. Plants obtained from northern nurseries, are planted through holes punched in this covering, irrigation tubing is run underneath. Runners are removed from the plants as they appear, in order to encourage the plants to put most of their energy into fruit development.
At the end of the harvest season, the plastic is removed and the plants are plowed into the ground. Because strawberry plants more than a year or two old begin to decline in productivity and fruit quality, this system of replacing the plants each year allows for improved yields and denser plantings. However, because it requires a longer growing season to allow for estab
The Fabaceae or Leguminosae known as the legume, pea, or bean family, are a large and economically important family of flowering plants. It includes trees and perennial or annual herbaceous plants, which are recognized by their fruit and their compound, stipulate leaves. Many legumes have characteristic fruits; the family is distributed, is the third-largest land plant family in terms of number of species, behind only the Orchidaceae and Asteraceae, with about 751 genera and about 19,000 known species. The five largest of the genera are Astragalus, Indigofera and Mimosa, which constitute about a quarter of all legume species; the ca. 19,000 known legume species amount to about 7% of flowering plant species. Fabaceae is the most common family found in tropical rainforests and in dry forests in the Americas and Africa. Recent molecular and morphological evidence supports the fact that the Fabaceae is a single monophyletic family; this conclusion has been supported not only by the degree of interrelation shown by different groups within the family compared with that found among the Leguminosae and their closest relations, but by all the recent phylogenetic studies based on DNA sequences.
These studies confirm that the Fabaceae are a monophyletic group, related to the Polygalaceae and Quillajaceae families and that they belong to the order Fabales. Along with the cereals, some fruits and tropical roots, a number of Leguminosae have been a staple human food for millennia and their use is related to human evolution; the Fabaceae family includes a number of important agricultural and food plants, including Glycine max, Pisum sativum, Cicer arietinum, Medicago sativa, Arachis hypogaea, Ceratonia siliqua, Glycyrrhiza glabra. A number of species are weedy pests in different parts of the world, including: Cytisus scoparius, Robinia pseudoacacia, Ulex europaeus, Pueraria lobata, a number of Lupinus species; the name'Fabaceae' comes from the defunct genus Faba, now included in Vicia. The term "faba" comes from Latin, appears to mean "bean". Leguminosae is an older name still considered valid, refers to the fruit of these plants, which are called legumes. Fabaceae range in habit from giant trees to small annual herbs, with the majority being herbaceous perennials.
Plants have indeterminate inflorescences. The flowers have a short hypanthium and a single carpel with a short gynophore, after fertilization produce fruits that are legumes; the Leguminosae have a wide variety of growth forms, including trees, herbaceous plants, vines or lianas. The herbaceous plants can be annuals, biennials, or perennials, without basal or terminal leaf aggregations. Many Legumes have tendrils, they are epiphytes, or vines. The latter support themselves by means of shoots that twist around a support or through cauline or foliar tendrils. Plants can be mesophytes, or xerophytes; the leaves are alternate and compound. Most they are even- or odd-pinnately compound trifoliate and palmately compound, in the Mimosoideae and the Caesalpinioideae bipinnate, they always have stipules, which can be rather inconspicuous. Leaf margins are entire or serrate. Both the leaves and the leaflets have wrinkled pulvini to permit nastic movements. In some species, leaflets have evolved into tendrils.
Many species have leaves with structures that attract ants that protect the plant from herbivore insects. Extrafloral nectaries are common among the Mimosoideae and the Caesalpinioideae, are found in some Faboideae. In some Acacia, the modified hollow stipules are known as domatia. Many Fabaceae host bacteria in their roots within structures called root nodules; these bacteria, known as rhizobia, have the ability to take nitrogen gas out of the air and convert it to a form of nitrogen, usable to the host plant. This process is called nitrogen fixation; the legume, acting as a host, rhizobia, acting as a provider of usable nitrate, form a symbiotic relationship. The flowers have five fused sepals and five free petals, they are hermaphrodite, have a short hypanthium cup shaped. There are ten stamens and one elongated superior ovary, with a curved style, they are arranged in indeterminate inflorescences. Fabaceae are entomophilous plants, the flowers are showy to attract pollinators. In the Caesalpinioideae, the flowers are zygomorphic, as in Cercis, or nearly symmetrical with five equal petals in Bauhinia.
The upper petal is the innermost one, unlike in the Faboideae. Some species, like some in the genus Senna, have asymmetric flowers, with one of the lower petals larger than the opposing one, the style bent to one side; the calyx, corolla, or stamens can be showy in this group. In the Mimosoideae, the flowers are actinomorphic and arranged in globose inflorescences; the petals are small and the stamens, which can be more than just 10, have long, coloured filaments, which are the showiest part of the flower. All of the flowers in an inflorescence open at once. In the Faboideae, the flowers are zygom
Plant reproductive morphology
Plant reproductive morphology is the study of the physical form and structure of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants have complex interplays between morphological adaptation and environmental factors in their sexual reproduction; the breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved both biotic and abiotic interactions. Charles Darwin's theories of natural selection utilized this work to build his theory of evolution, which includes analysis of the coevolution of flowers and their insect pollinators.
Plants have complex lifecycles involving alternation of generations. One generation, the sporophyte, gives rise to the next generation asexually via spores. Spores may be identical isospores or come in different sizes, but speaking and sporophytes are neither male nor female because they do not produce gametes; the alternate generation, the gametophyte, sperm. A gametophyte can be monoicous, producing both eggs and sperm or dioicous, either male. In the bryophytes, the sexual gametophyte is the dominant generation. In ferns and seed plants the sporophyte is the dominant generation; the obvious visible plant, whether a small herb or a large tree, is the sporophyte, the gametophyte is small. In seed plants, each female gametophyte, the spore that gives rise to it, is hidden within the sporophyte and is dependent on it for nutrition; each male gametophyte consists of from two to four cells enclosed within the protective wall of a pollen grain. The sporophyte of a flowering plant is described using sexual terms based on the sexuality of the gametophyte it gives rise to.
For example, a sporophyte that produces spores that give rise only to male gametophytes may be described as "male" though the sporophyte itself is asexual, producing only spores. Flowers produced by the sporophyte may be described as "unisexual" or "bisexual", meaning that they give rise to either one sex of gametophyte or both sexes of gametophyte; the flower is the characteristic structure concerned with sexual reproduction in flowering plants. Flowers vary enormously in their construction. A "complete" flower, like that of Ranunculus glaberrimus shown in the figure, has a calyx of outer sepals and a corolla of inner petals; the sepals and petals together form the perianth. Next inwards there are numerous stamens, which produce pollen grains, each containing a microscopic male gametophyte. Stamens may collectively form the androecium. In the middle there are carpels, which at maturity contain one or more ovules, within each ovule is a tiny female gametophyte. Carpels may collectively form the gynoecium.
Each carpel in Ranunculus species is an achene that produces one ovule, which when fertilized becomes a seed. If the carpel contains more than one seed, as in Eranthis hyemalis, it is called a follicle. Two or more carpels may be fused together to varying degrees and the entire structure, including the fused styles and stigmas may be called a pistil; the lower part of the pistil, where the ovules are produced, is called the ovary. It may be divided into chambers corresponding to the separate carpels. A "perfect" flower has both stamens and carpels, may be described as "bisexual" or "hermaphroditic". A "unisexual" flower is one in which either the stamens or the carpels are missing, vestigial or otherwise non-functional; each flower is either "staminate" and thus "male", or "carpellate" and thus "female". If separate staminate and carpellate flowers are always found on the same plant, the species is called monoecious. If separate staminate and carpellate flowers are always found on different plants, the species is called dioecious.
A 1995 study found that about 6% of angiosperm species are dioecious, that 7% of genera contain some dioecious species. Members of the birch family are examples of monoecious plants with unisexual flowers. A mature alder tree produces long catkins containing only male flowers, each with four stamens and a minute perianth, separate stalked groups of female flowers, each without a perianth. Most hollies are dioecious; each plant produces either functionally functionally female flowers. In Ilex aquifolium, the common European holly, both kinds of flower have four sepals and four white petals. Since only female plants are able to set fruit and produce berries, this has consequences for gardeners. Amborella represents the first known group of flowering plants to separate from their common ancestor, it too is dioecio
In botany, a fruit is the seed-bearing structure in flowering plants formed from the ovary after flowering. Fruits are the means. Edible fruits, in particular, have propagated with the movements of humans and animals in a symbiotic relationship as a means for seed dispersal and nutrition. Accordingly, fruits account for a substantial fraction of the world's agricultural output, some have acquired extensive cultural and symbolic meanings. In common language usage, "fruit" means the fleshy seed-associated structures of a plant that are sweet or sour, edible in the raw state, such as apples, grapes, lemons and strawberries. On the other hand, in botanical usage, "fruit" includes many structures that are not called "fruits", such as bean pods, corn kernels and wheat grains; the section of a fungus that produces spores is called a fruiting body. Many common terms for seeds and fruit do not correspond to the botanical classifications. In culinary terminology, a fruit is any sweet-tasting plant part a botanical fruit.
However, in botany, a fruit is the ripened ovary or carpel that contains seeds, a nut is a type of fruit and not a seed, a seed is a ripened ovule. Examples of culinary "vegetables" and nuts that are botanically fruit include corn, eggplant, sweet pepper, tomato. In addition, some spices, such as allspice and chili pepper, are fruits. In contrast, rhubarb is referred to as a fruit, because it is used to make sweet desserts such as pies, though only the petiole of the rhubarb plant is edible, edible gymnosperm seeds are given fruit names, e.g. ginkgo nuts and pine nuts. Botanically, a cereal grain, such as corn, rice, or wheat, is a kind of fruit, termed a caryopsis. However, the fruit wall is thin and is fused to the seed coat, so all of the edible grain is a seed; the outer edible layer, is the pericarp, formed from the ovary and surrounding the seeds, although in some species other tissues contribute to or form the edible portion. The pericarp may be described in three layers from outer to inner, the epicarp and endocarp.
Fruit that bears a prominent pointed terminal projection is said to be beaked. A fruit results from maturation of one or more flowers, the gynoecium of the flower forms all or part of the fruit. Inside the ovary/ovaries are one or more ovules where the megagametophyte contains the egg cell. After double fertilization, these ovules will become seeds; the ovules are fertilized in a process that starts with pollination, which involves the movement of pollen from the stamens to the stigma of flowers. After pollination, a tube grows from the pollen through the stigma into the ovary to the ovule and two sperm are transferred from the pollen to the megagametophyte. Within the megagametophyte one of the two sperm unites with the egg, forming a zygote, the second sperm enters the central cell forming the endosperm mother cell, which completes the double fertilization process; the zygote will give rise to the embryo of the seed, the endosperm mother cell will give rise to endosperm, a nutritive tissue used by the embryo.
As the ovules develop into seeds, the ovary begins to ripen and the ovary wall, the pericarp, may become fleshy, or form a hard outer covering. In some multiseeded fruits, the extent to which the flesh develops is proportional to the number of fertilized ovules; the pericarp is differentiated into two or three distinct layers called the exocarp and endocarp. In some fruits simple fruits derived from an inferior ovary, other parts of the flower, fuse with the ovary and ripen with it. In other cases, the sepals, petals and/or stamens and style of the flower fall off; when such other floral parts are a significant part of the fruit, it is called an accessory fruit. Since other parts of the flower may contribute to the structure of the fruit, it is important to study flower structure to understand how a particular fruit forms. There are three general modes of fruit development: Apocarpous fruits develop from a single flower having one or more separate carpels, they are the simplest fruits. Syncarpous fruits develop from a single gynoecium having two or more carpels fused together.
Multiple fruits form from many different flowers. Plant scientists have grouped fruits into three main groups, simple fruits, aggregate fruits, composite or multiple fruits; the groupings are not evolutionarily relevant, since many diverse plant taxa may be in the same group, but reflect how the flower organs are arranged and how the fruits develop. Simple fruits can be either dry or fleshy, result from the ripening of a simple or compound ovary in a flower with only one pistil. Dry fruits may be either dehiscent, or indehiscent. Types of dry, simple fruits, examples of each, include: achene – most seen in aggregate fruits capsule – caryopsis – cypsela – an achene-like fruit derived from the individual florets in a capitulum. Fibrous drupe – follicle – is formed from a single carpel, opens by one suture
Hornworts are a group of non-vascular plants constituting the division Anthocerotophyta. The common name refers to the elongated horn-like structure, the sporophyte; as in mosses and liverworts, the flattened, green plant body of a hornwort is the gametophyte plant. Hornworts may be found worldwide, though they tend to grow only in places that are humid; some species grow in large numbers as tiny weeds in the soil of cultivated fields. Large tropical and sub-tropical species of Dendroceros may be found growing on the bark of trees; the total number of species is still uncertain. While there are more than 300 published species names, the actual number could be as low as 100-150 species; the plant body of a hornwort is a haploid gametophyte stage. This stage grows as a thin rosette or ribbon-like thallus between one and five centimeters in diameter; each cell of the thallus contains just one chloroplast. In most species, this chloroplast is fused with other organelles to form a large pyrenoid that both manufactures and stores food.
This particular feature is unusual in land plants, but is common among algae. Many hornworts develop internal mucilage-filled cavities; these cavities are invaded by photosynthetic cyanobacteria species of Nostoc. Such colonies of bacteria growing inside the thallus give the hornwort a distinctive blue-green color. There may be small slime pores on the underside of the thallus; these pores superficially resemble the stomata of other plants. The horn-shaped sporophyte grows from an archegonium embedded deep in the gametophyte; the sporophyte of a hornwort is unusual in that it grows from a meristem near its base, instead of from its tip the way other plants do. Unlike liverworts, most hornworts have true stomata on their sporophyte; the exceptions are the genera Megaceros, which do not have stomata. The sporophyte of most hornworts are photosynthetic, not the case with liverworts; when the sporophyte is mature, it has a multicellular outer layer, a central rod-like columella running up the center, a layer of tissue in between that produces spores and pseudo-elaters.
The pseudo-elaters are multi-cellular, unlike the elaters of liverworts. They have helical thickenings. Hornwort spores are large for bryophytes, measuring between 30 and 80 µm in diameter or more; the spores are polar with a distinctive Y-shaped tri-radiate ridge on the proximal surface, with a distal surface ornamented with bumps or spines The life of a hornwort starts from a haploid spore. In most species, there is a single cell inside the spore, a slender extension of this cell called the germ tube germinates from the proximal side of the spore; the tip of the germ tube divides to form an octant of cells, the first rhizoid grows as an extension of the original germ cell. The tip continues to divide new cells. By contrast, species of the family Dendrocerotaceae may begin dividing within the spore, becoming multicellular and photosynthetic before the spore germinates. In either case, the protonema is a transitory stage in the life of a hornwort. From the protonema grows the adult gametophyte, the persistent and independent stage in the life cycle.
This stage grows as a thin rosette or ribbon-like thallus between one and five centimeters in diameter, several layers of cells in thickness. It is green or yellow-green from the chlorophyll in its cells, or bluish-green when colonies of cyanobacteria grow inside the plant; when the gametophyte has grown to its adult size, it produces the sex organs of the hornwort. Most plants are monoecious, with both sex organs on the same plant, but some plants are dioecious, with separate male and female gametophytes; the female organs are known as archegonia and the male organs are known as antheridia. Both kinds of organs develop just below the surface of the plant and are only exposed by disintegration of the overlying cells; the biflagellate sperm must swim from the antheridia, or else be splashed to the archegonia. When this happens, the sperm and egg cell fuse to form a zygote, the cell from which the sporophyte stage of the life cycle will develop. Unlike all other bryophytes, the first cell division of the zygote is longitudinal.
Further divisions produce three basic regions of the sporophyte. At the bottom of the sporophyte, is a foot; this is a globular group of cells that receives nutrients from the parent gametophyte, on which the sporophyte will spend its entire existence. In the middle of the sporophyte, is a meristem that will continue to divide and produce new cells for the third region; this third region is the capsule. Both the central and surface cells of the capsule are sterile, but between them is a layer of cells that will divide to produce pseudo-elaters and spores; these are released from the capsule. While the fossil record of crown group hornworts only begins in the upper Cretaceous, the lower Devonian Horneophyton may represent a stem group to the clade, as it possesses a sporangium with central columella not attached at the roof. However, the same form of columella is characteristic of basal moss groups, such as the Sphagnopsida and Andreaeopsida, has been interpreted as a character common to all early land plants with stomata.
Hornworts were traditionally considered a class within the division Bryophyta. However, it now appears that this former division is paraphyletic, so the hornworts
A seed is an embryonic plant enclosed in a protective outer covering. The formation of the seed is part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm plants. Seeds are the product of the ripened ovule, after fertilization by pollen and some growth within the mother plant; the embryo is developed from the seed coat from the integuments of the ovule. Seeds have been an important development in the reproduction and success of gymnosperm and angiosperm plants, relative to more primitive plants such as ferns and liverworts, which do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates; the term "seed" has a general meaning that antedates the above – anything that can be sown, e.g. "seed" potatoes, "seeds" of corn or sunflower "seeds". In the case of sunflower and corn "seeds", what is sown is the seed enclosed in a shell or husk, whereas the potato is a tuber.
Many structures referred to as "seeds" are dry fruits. Plants producing berries are called baccate. Sunflower seeds are sometimes sold commercially while still enclosed within the hard wall of the fruit, which must be split open to reach the seed. Different groups of plants have other modifications, the so-called stone fruits have a hardened fruit layer fused to and surrounding the actual seed. Nuts are the one-seeded, hard-shelled fruit of some plants with an indehiscent seed, such as an acorn or hazelnut. Seeds are produced in several related groups of plants, their manner of production distinguishes the angiosperms from the gymnosperms. Angiosperm seeds are produced in a hard or fleshy structure called a fruit that encloses the seeds for protection in order to secure healthy growth; some fruits have layers of both fleshy material. In gymnosperms, no special structure develops to enclose the seeds, which begin their development "naked" on the bracts of cones. However, the seeds do become covered by the cone scales.
Seed production in natural plant populations varies from year to year in response to weather variables and diseases, internal cycles within the plants themselves. Over a 20-year period, for example, forests composed of loblolly pine and shortleaf pine produced from 0 to nearly 5 million sound pine seeds per hectare. Over this period, there were six bumper, five poor, nine good seed crops, when evaluated for production of adequate seedlings for natural forest reproduction. Angiosperm seeds consist of three genetically distinct constituents: the embryo formed from the zygote, the endosperm, triploid, the seed coat from tissue derived from the maternal tissue of the ovule. In angiosperms, the process of seed development begins with double fertilization, which involves the fusion of two male gametes with the egg cell and the central cell to form the primary endosperm and the zygote. Right after fertilization, the zygote is inactive, but the primary endosperm divides to form the endosperm tissue.
This tissue becomes the food the young plant will consume until the roots have developed after germination. After fertilization the ovules develop into the seeds; the ovule consists of a number of components: The funicle or seed stalk which attaches the ovule to the placenta and hence ovary or fruit wall, at the pericarp. The nucellus, the remnant of the megasporangium and main region of the ovule where the megagametophyte develops; the micropyle, a small pore or opening in the apex of the integument of the ovule where the pollen tube enters during the process of fertilization. The chalaza, the base of the ovule opposite the micropyle, where integument and nucellus are joined together; the shape of the ovules as they develop affects the final shape of the seeds. Plants produce ovules of four shapes: the most common shape is called anatropous, with a curved shape. Orthotropous ovules are straight with all the parts of the ovule lined up in a long row producing an uncurved seed. Campylotropous ovules have a curved megagametophyte giving the seed a tight "C" shape.
The last ovule shape is called amphitropous, where the ovule is inverted and turned back 90 degrees on its stalk. In the majority of flowering plants, the zygote's first division is transversely oriented in regards to the long axis, this establishes the polarity of the embryo; the upper or chalazal pole becomes the main area of growth of the embryo, while the lower or micropylar pole produces the stalk-like suspensor that attaches to the micropyle. The suspensor absorbs and manufactures nutrients from the endosperm that are used during the embryo's growth; the main components of the embryo are: The cotyledons, the seed leaves, attached to the embryonic axis. There may be two; the cotyledons are the source of nutrients in the non-endospermic dicotyledons, in which case they replace the endosperm, are thick and leathery. In endospermic seeds the cotyledons are papery. Dicotyledons have the point of attachment opposite one another on the axis; the epicotyl, the embryonic axis above the point of attachment of the cotyledon.
The plumule, the tip of the epicotyl, has a feathery appearance due to the presence of young leaf primordia at the apex, will become the shoot upon germination. The hypocotyl, the embryonic axis below the point of attachment of the cotyledon, connecting the epicotyl and the radicle, being the stem-root transition zone; the radicle, the basal tip of the hy
Ranunculus is a genus of about 500 species of flowering plants in the family Ranunculaceae. Members of the genus include the buttercups and water crowfoots; the petals are highly lustrous in yellow species, owing to a special coloration mechanism: the petal's upper surface is smooth causing a mirror-like reflection. The flash aids in attracting pollinating insects and temperature regulation of the flower's reproductive organs. Buttercups flower in the spring, but flowers may be found throughout the summer where the plants are growing as opportunistic colonizers, as in the case of garden weeds; the water crowfoots, which grow in still or running water, are sometimes treated in a separate genus Batrachium. They have thread-like leaves underwater and broader floating leaves. In some species, such as R. aquatilis, a third, intermediate leaf type occurs. Ranunculus species are used as food by the larvae of some Lepidoptera species including Hebrew Character and small angle shades; some species are popular ornamental flowers in horticulture, with many cultivars selected for large and brightly coloured flowers.
Buttercups are perennial, but annual or biennial, aquatic or terrestrial plants with leaves in a rosette at the base of the stem. In many perennial species runners are sent out that will develop new plants with roots and rosettes at the distanced nodes; the leaves lack stipules, have stems, are palmately veined, more or less incised, or compound, leaflets or leaf segments may be fine and linear in aquatic species. The hermaphrodite flowers are single or in a cyme, have five green sepals and five yellow, greenish or white petals that are sometimes flushed with red, purple or pink. At the base of each petal is one nectary gland, naked or may be covered by a scale. Anthers may be few, but many are arranged in a spiral, are yellow or sometimes white, with yellow pollen; the sometimes few but many green or yellow carpels are not fused and are arranged in a spiral on a globe or dome-shaped receptacle. The fruits may be smooth or hairy, nobby or have hooked spines; the name Ranunculus is Late Latin for the diminutive of rana.
This refers to many species being found near water, like frogs. The name buttercup may derive from a false belief that the plants give butter its characteristic yellow hue. A popular children's game involves holding a buttercup up to the chin. In the interior of the Pacific Northwest of the United States, the buttercup is called "Coyote’s eyes"—ʔiceyéeyenm sílu in Nez Perce and spilyaynmí áčaš in Sahaptin. In the legend, Coyote was tossing his eyes up in the air and catching them again when Eagle snatched them. Unable to see, Coyote made eyes from the buttercup. Molecular investigation of the genus has revealed that Ranunculus is not monophyletic with respect to a number of other recognized genera in the family – e.g. Ceratocephala, Hamadryas, Myosurus, Oxygraphis and Trautvetteria. A proposal to split Ranunculus into several genera has thus been published in a new classification for the tribe Ranunculeae; the split genera include Beckwithia Jeps. Callianthemoides Tamura, Coptidium Beurl. Ex Rydb.
Cyrtorhyncha Nutt. Ex Torr. & A. Gray, Ficaria Guett. Krapfia DC. Kumlienia E. Greene and Peltocalathos Tamura. Not all taxonomists and users accept this splitting of the genus, it can alternatively be treated in the broad sense; the most common uses of Ranunculus species in traditional medicines are anti-rheumatism, intermittent fever and rubefacient. The findings in some Ranunculus species of, for example, anemonin, may justify the uses of these species against fever and rubefacient in Asian traditional medicines. All Ranunculus species are poisonous when eaten fresh, but their acrid taste and the blistering of the mouth caused by their poison means they are left uneaten. Poisoning in livestock can occur where buttercups are abundant in overgrazed fields where little other edible plant growth is left, the animals eat them out of desperation. Symptoms of poisoning include bloody diarrhea, excessive salivation and severe blistering of the mouth, mucous membranes and gastrointestinal tract; when Ranunculus plants are handled occurring ranunculin is broken down to form protoanemonin, known to cause contact dermatitis in humans and care should therefore be exercised in extensive handling of the plants.
The toxins are degraded by drying, so hay containing dried buttercups is safe. †Ranunculus gailensis and †Ranunculus tanaiticus seed fossils have been described from the Pliocene Borsoni Formation in the Rhön Mountains, central Germany. Ranunculus abortivus – littleleaf buttercup Ranunculus acaulis – dune, sand or shore buttercup Ranunculus aconitifolius – aconite-leaf buttercup Ranunculus acraeus – a newly described species from Otago, New Zealand Ranunculus acris – meadow buttercup Ranunculus aestivalis Ranunculus alismifolius – plantainleaf buttercup Ranunculus allenii Ranunculus amphitrichus Ranunculus andersonii – Anderson's buttercup Ranunculus anemoneus Ranunculus aquatilis – common water crowfoot Ranunculus arvensis – corn buttercup Ranunculus asiaticus – Persian buttercup Ranunculus auricomus – Goldilocks b