In botany , the petiole ( / ˈ p iː t i . oʊ l / ) is the stalk that attaches the leaf blade to the stem . It is able to twist the leaf to face the sun, producing a characteristic foliage arrangement (spacing of blades), and also optimizing its exposure to sunlight. Outgrowths appearing on each side of the petiole in some species are called stipules . The terms petiolate and apetiolate are applied respectively to leaves with and without petioles.
31-468: About 12; see text Perideridia is a genus of plants in the family Apiaceae . Plants in this genus are known generally as yampah or yampa . They are native to western North America. Similar in appearance to other plants of the family Apiaceae , they have umbels of white flowers. The genus is based on the Greek word perideri , meaning 'necklace'. The plants have a unique appearance for members of
62-465: A family in which the leaves are always sessile. In some other plant groups, such as the speedwell genus Veronica , petiolate and sessile leaves may occur in different species. In the grasses ( Poaceae ), the leaves are apetiolate, but the leaf blade may be narrowed at the junction with the leaf sheath to form a pseudopetiole , as in Pseudosasa japonica . In plants with compound leaves ,
93-465: A gentle laxative if consumed in excess and were used medicinally for this purpose. It resembles the highly toxic poison hemlock and water hemlock . Apiaceae Umbelliferae Apiaceae ( / eɪ p iː ˈ eɪ s i ˌ aɪ , - s iː ˌ iː / ) or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus Apium , and commonly known as the celery , carrot or parsley family , or simply as umbellifers . It
124-403: A marked smell when crushed, aromatic to fetid, but absent in some species. The defining characteristic of this family is the inflorescence , the flowers nearly always aggregated in terminal umbels , that may be simple or more commonly compound, often umbelliform cymes . The flowers are usually perfect ( hermaphroditic ), and actinomorphic , but there may be zygomorphic flowers at the edge of
155-529: A petiolule is called a pulvinulus. In some plants, the petioles are flattened and widened to become phyllodes (also known as phyllodia or cladophylls) and the true leaves may be reduced or absent. Thus, the phyllode comes to serve the functions of the leaf. Phyllodes are common in the genus Acacia , especially the Australian species, at one time put in Acacia subgenus Phyllodineae . In Acacia koa ,
186-825: A result are flavourful aromatic herbs. Examples are parsley ( Petroselinum crispum ), coriander ( Coriandrum sativum ), culantro , and dill ( Anethum graveolens ). The seeds may be used in cuisine, as with coriander ( Coriandrum sativum ), fennel ( Foeniculum vulgare ), cumin ( Cuminum cyminum ), and caraway ( Carum carvi ). Other notable cultivated Apiaceae include chervil ( Anthriscus cerefolium ), angelica ( Angelica spp.), celery ( Apium graveolens ), arracacha ( Arracacia xanthorrhiza ), sea holly ( Eryngium spp.), asafoetida ( Ferula asafoetida ), galbanum ( Ferula gummosa ), cicely ( Myrrhis odorata ), anise ( Pimpinella anisum ), lovage ( Levisticum officinale ), and hacquetia ( Sanicula epipactis ). Generally, all members of this family are best cultivated in
217-401: Is a stalk that attaches a leaf to the plant stem. In petiolate leaves the leaf stalk may be long (as in the leaves of celery and rhubarb ), or short (for example basil ). When completely absent, the blade attaches directly to the stem and is said to be sessile . Subpetiolate leaves have an extremely short petiole, and may appear sessile. The broomrape family Orobanchaceae is an example of
248-579: Is common. The gynoecium consists of two carpels fused into a single, bicarpellate pistil with an inferior ovary . Stylopodia support two styles, and secrete nectar, attracting pollinators like flies, mosquitoes, gnats, beetles, moths, and bees. The fruit is a schizocarp consisting of two fused carpels that separate at maturity into two mericarps, each containing a single seed. The fruits of many species are dispersed by wind but others such as those of Daucus spp., are covered in bristles, which may be hooked in sanicle Sanicula europaea and thus catch in
279-600: Is derived from the type genus Apium , which was originally used by Pliny the Elder circa 50 AD for a celery -like plant. The alternative name for the family, Umbelliferae, derives from the inflorescence being generally in the form of a compound umbel . The family was one of the first to be recognized as a distinct group in Jacques Daleschamps' 1586 Historia generalis plantarum . With Robert Morison's 1672 Plantarum umbelliferarum distribution nova it became
310-421: Is often variation in the functionality of the stamens even within a single inflorescence. Some flowers are functionally staminate (where a pistil may be present but has no ovules capable of being fertilized) while others are functionally pistillate (where stamens are present but their anthers do not produce viable pollen). Pollination of one flower by the pollen of a different flower of the same plant ( geitonogamy )
341-408: Is the 16th-largest family of flowering plants, with more than 3,800 species in about 446 genera , including such well-known, and economically important plants as ajwain , angelica , anise , asafoetida , caraway , carrot , celery , chervil , coriander , cumin , dill , fennel , lovage , cow parsley , parsley , parsnip and sea holly , as well as silphium , a plant whose exact identity
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#1732772630250372-416: Is unclear and may be extinct. The family Apiaceae includes a significant number of phototoxic species, such as giant hogweed , and a smaller number of highly poisonous species, such as poison hemlock , water hemlock , spotted cowbane , fool's parsley , and various species of water dropwort . Most Apiaceae are annual , biennial or perennial herbs (frequently with the leaves aggregated toward
403-404: The parsley family, and are tall (1–3 feet) and grasslike, with threadlike leaves 1–6 inches long that resemble blades of grass. The plants effectively mimic tall grass and are virtually invisible until they flower, since they tend to grow in grassy meadows, and prefer full sunlight. Like most members of the parsley family, yampah produces umbels of white flowers. The small roots of yampah are about
434-446: The rhizome and produces the leaf at its end. Botanically, it is categorized as a vegetable but, culinarily, it is more often used as a fruit. The longest known petiole is that of the royal waterlily or iaupê jaçanã Victoria amazonica which is up to 23 ft (7.0 m) in length. 'Petiole' comes from Latin petiolus , or 'little foot', 'stem', an alternative diminutive of 'pes', 'foot'. The regular diminutive 'pediculus'
465-553: The World Online (PoWO) accepted 444 genera, while GRIN Taxonomy accepted 462. The PoWO genera are not a subset of those in GRIN; for example, Haloselinum is accepted by PoWO but not by GRIN, while Halosciastrum is accepted by GRIN but not by PoWO, which treats it as a synonym of Angelica . The Angiosperm Phylogeny Website had an "approximate list" of 446 genera. The black swallowtail butterfly, Papilio polyxenes , uses
496-512: The base), though a minority are woody shrubs or small trees such as Bupleurum fruticosum . Their leaves are of variable size, and alternately arranged , or with the upper leaves becoming nearly opposite. The leaves may be petiolate or sessile . There are no stipules but the petioles are frequently sheathing, and the leaves may be perfoliate . The leaf blade is usually dissected, ternate , or pinnatifid , but simple, and entire in some genera, e.g. Bupleurum . Commonly, their leaves emit
527-409: The cool-season garden; they may not grow at all if the soils are too warm. Almost every widely cultivated plant of this group is a considered useful as a companion plant . One reason is that the tiny flowers, clustered into umbels, are well suited for ladybugs , parasitic wasps , and predatory flies , which drink nectar when not reproducing. They then prey upon insect pests on nearby plants. Some of
558-456: The family Apiaceae for food and host plants for oviposition . The 22-spot ladybird is also commonly found eating mildew on these plants. Many members of this family are cultivated for various purposes. Parsnip ( Pastinaca sativa ), carrot ( Daucus carota ) and Hamburg parsley ( Petroselinum crispum ) produce tap roots that are large enough to be useful as food. Many species produce essential oils in their leaves or fruits and as
589-433: The family Apiaceae produce phototoxic substances (called furanocoumarins ) that sensitize human skin to sunlight. Contact with plant parts that contain furanocoumarins, followed by exposure to sunlight, may cause phytophotodermatitis , a serious skin inflammation. Phototoxic species include Ammi majus , Notobubon galbanum , the parsnip ( Pastinaca sativa ) and numerous species of the genus Heracleum , especially
620-507: The first group of plants for which a systematic study was published. The family is solidly placed within the Apiales order in the APG III system . It is closely related to Araliaceae and the boundaries between these families remain unclear. Traditionally groups within the family have been delimited largely based on fruit morphology , and the results from this have not been congruent with
651-427: The fur of animals. The seeds have an oily endosperm and often contain essential oils, containing aromatic compounds that are responsible for the flavour of commercially important umbelliferous seed such as anise , cumin and coriander . The shape and details of the ornamentation of the ripe fruits are important for identification to species level. Apiaceae was first described by John Lindley in 1836. The name
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#1732772630250682-615: The genera Klotzschia and Hermas fell outside the four subfamilies. It was suggested that they could be accommodated in subfamilies of their own. Phlyctidocarpa was formerly placed in the subfamily Apioideae, but if kept there makes Apioideae paraphyletic . It could be placed in an enlarged Saniculoideae, or restored to Apioideae if the latter were expanded to include Saniculoideae. The subfamilies can be further divided into tribes and clades, with many clades falling outside formally recognized tribes. The number of genera accepted by sources varies. As of December 2022 , Plants of
713-615: The giant hogweed ( Heracleum mantegazzianum ). Of all the plant species that have been reported to induce phytophotodermatitis, approximately half belong to the family Apiaceae. The family Apiaceae also includes a smaller number of poisonous species, including poison hemlock , water hemlock , spotted cowbane , fool's parsley , and various species of water dropwort . Some members of the family Apiaceae, including carrot , celery , fennel , parsley and parsnip , contain polyynes , an unusual class of organic compounds that exhibit cytotoxic effects. Petiole (botany) The petiole
744-438: The leaflets are attached to a continuation of the petiole called the rachis . Each leaflet may be attached to the rachis by a short stalk called the petiolule. There may be swollen regions at either end of the petiole known as pulvina (singular = pulvinus ) that are composed of a flexible tissue that allows leaf movement. Pulvina are common in the bean family Fabaceae and the prayer plant family Marantaceae . A pulvinus on
775-783: The members of this family considered "herbs" produce scents that are believed to mask the odours of nearby plants, thus making them harder for insect pests to find. The poisonous members of the Apiaceae have been used for a variety of purposes globally. The poisonous Oenanthe crocata has been used as an aid in suicides, and arrow poisons have been made from various other family species. Daucus carota has been used as coloring for butter. Dorema ammoniacum , Ferula galbaniflua , and Ferula moschata (sumbul) are sources of incense . The woody Azorella compacta Phil. has been used in South America for fuel. Many species in
806-560: The more recent molecular phylogenetic analyses. The subfamilial and tribal classification for the family is currently in a state of flux, with many of the groups being found to be grossly paraphyletic or polyphyletic . Prior to molecular phylogenetic studies, the family was subdivided primarily based on fruit characteristics. Molecular phylogenetic analyses from the mid-1990s onwards have shown that fruit characters evolved in parallel many times, so that using them in classification resulted in units that were not monophyletic . In 2004, it
837-483: The phyllodes are leathery and thick, allowing the tree to survive stressful environments. The petiole allows partially submerged hydrophytes to have leaves floating at different depths, the petiole being between the node and the stem. In plants such as rhubarb ( Rheum rhabarbarum ), celery ( Apium graveolens ), artichokes , and cardoons ( Cynara cardunculus ), the petioles ('stalks' or 'ribs') are cultivated as edible crops. The petiole of rhubarb grows directly from
868-468: The plant are crunchy and mildly sweet, and resemble water chestnuts in texture and flavor. Yampah roots were either baked or steamed, and were reported to have excellent flavor and nutritional qualities. The seeds of yampah were used as a seasoning and resemble caraway seeds in flavor. Yampah roots contain rapidly assimilatable carbohydrates, and were used by hunters and runners as a high energy food to enhance physical endurance. Uncooked yampah roots are
899-478: The size of a large unshelled peanut. The plants are widely distributed in moist open meadows and hillsides up to 7,500 feet (2,300 m) across Western North America. Plains Indians named the plant 'Yampah' and consumed its starchy bulbs, some of which taste like carrots. Perideridia gairdneri was an important staple crop of Native Americans in Western North America. The nutlike roots of
930-593: The umbel, as in carrot ( Daucus carota ) and coriander , with petals of unequal size, the ones pointing outward from the umbel larger than the ones pointing inward. Some are andromonoecious, polygamomonoecious, or even dioecious (as in Acronema ), with a distinct calyx , and corolla , but the calyx is often highly reduced, to the point of being undetectable in many species, while the corolla can be white, yellow, pink or purple. The flowers are nearly perfectly pentamerous , with five petals and five stamens . There
961-478: Was proposed that Apiaceae should be divided into four subfamilies: Apioideae is by far the largest subfamily with about 90% of the genera. Most subsequent studies have supported this division, although leaving some genera unplaced. A 2021 study suggested the relationships shown in the following cladogram. Platysace Mackinlayoideae Klotzschia Azorelloideae Hermas Phlyctidocarpa + Saniculoideae Apioideae The Platysace clade and