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82-414: § Evolutionary lines and subgenera Allium is a large genus of monocotyledonous flowering plants with around 1000 different species accepted in botanical science, making Allium the largest genus in the Amaryllidaceae plant family and places Allium amongst the largest plant genera in the world. Many of the species are edible, and some have a long history of cultivation and human consumption as

164-405: A petiole . The flowers, which are produced on scapes are erect or in some species pendent, having six petal-like tepals produced in two whorls. The flowers have one style and six epipetalous stamens ; the anthers and pollen can vary in color depending on the species. The ovaries are superior, and three-lobed with three locules . The fruits are capsules that open longitudinally along

246-444: A phylogenetic tree to be constructed for the flowering plants. The establishment of major new clades necessitated a departure from the older but widely used classifications such as Cronquist and Thorne, based largely on morphology rather than genetic data. These developments complicated discussions on plant evolution and necessitated a major taxonomic restructuring. This DNA based molecular phylogenetic research confirmed on

328-416: A brief history, see Li et al. (2010) The modern era of phylogenetic analysis dates to 1996. In 2006 Friesen, Fritsch, and Blattner described a new classification with 15 subgenera , 56 sections , and about 780 species based on the nuclear ribosomal gene internal transcribed spacers . Some of the subgenera correspond to the once separate genera ( Caloscordum , Milula , Nectaroscordum ) included in

410-719: A classification of flowering plants (florifera) based on a division by the number of cotyledons, but developed his ideas over successive publications, coining the terms Monocotyledones and Dicotyledones in 1703, in the revised version of his Methodus ( Methodus plantarum emendata ), as a primary method for dividing them, Herbae floriferae, dividi possunt, ut diximus, in Monocotyledones & Dicotyledones (Flowering plants, can be divided, as we have said, into Monocotyledons & Dicotyledons). Although Linnaeus (1707–1778) did not utilise Ray's discovery, basing his own classification solely on floral reproductive morphology ,

492-401: A minor one is found in western North America. The genus is especially diverse in the eastern Mediterranean . Species grow in various conditions from dry, well-drained mineral-based soils to moist, organic soils; most grow in sunny locations, but a number also grow in forests (e.g., A. ursinum ), or even in swamps or water. Various Allium species are used as food plants by the larvae of

574-573: A mixture of characteristics. Nymphaeaceae (water lilies) have reticulate veins, a single cotyledon, adventitious roots, and a monocot-like vascular bundle. These examples reflect their shared ancestry. Nevertheless, this list of traits is generally valid, especially when contrasting monocots with eudicots , rather than non-monocot flowering plants in general. Monocot apomorphies (characteristics derived during radiation rather than inherited from an ancestral form) include herbaceous habit, leaves with parallel venation and sheathed base, an embryo with

656-505: A number of taxonomic groupings previously considered separate genera ( Caloscordum Herb., Milula Prain and Nectaroscordum Lindl.) Allium spicatum had been treated by many authors as Milula spicata , the only species in the monospecific genus Milula . In 2000, it was shown to be embedded in Allium . Tribe Allieae (monogeneric, Allium ) Tribe Tulbaghieae Tribes Gilliesieae , Leucocoryneae When Linnaeus formerly described

738-483: A proximal leaf base or hypophyll and a distal hyperphyll. In monocots the hypophyll tends to be the dominant part in contrast to other angiosperms. From these, considerable diversity arises. Mature monocot leaves are generally narrow and linear, forming a sheathing around the stem at its base, although there are many exceptions. Leaf venation is of the striate type, mainly arcuate-striate or longitudinally striate (parallel), less often palmate-striate or pinnate-striate with

820-401: A quarter of all angiosperms. The largest family in this group (and in the flowering plants as a whole) by number of species are the orchids (family Orchidaceae ), with more than 20,000 species. About 12,000 species belong to the true grasses ( Poaceae ), which are economically the most important family of monocotyledons. Often mistaken for grasses, sedges are also monocots. In agriculture

902-582: A short axial body bearing leaves whose bases store food. Additional outer non-storage leaves may form a protective function (Tillich, Figure 12). Other storage organs may be tubers or corms , swollen axes. Tubers may form at the end of underground runners and persist. Corms are short lived vertical shoots with terminal inflorescences and shrivel once flowering has occurred. However, intermediate forms may occur such as in Crocosmia (Asparagales). Some monocots may also produce shoots that grow directly down into

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984-617: A similar position as a major division of the flowering plants throughout the nineteenth century, with minor variations. George Bentham and Hooker (1862–1883) used Monocotyledones, as would Wettstein , while August Eichler used Mononocotyleae and Engler , following de Candolle, Monocotyledoneae. In the twentieth century, some authors used alternative names such as Bessey 's (1915) Alternifoliae and Cronquist 's (1966) Liliatae. Later (1981) Cronquist changed Liliatae to Liliopsida, usages also adopted by Takhtajan simultaneously. Thorne (1992) and Dahlgren (1985) also used Liliidae as

1066-425: A single cotyledon, an atactostele , numerous adventitious roots, sympodial growth, and trimerous (3 parts per whorl ) flowers that are pentacyclic (5 whorled) with 3 sepals, 3 petals, 2 whorls of 3 stamens each, and 3 carpels. In contrast, monosulcate pollen is considered an ancestral trait, probably plesiomorphic . The distinctive features of the monocots have contributed to the relative taxonomic stability of

1148-401: A smaller group were grass-like plants with long straight parallel veins. In doing so he distinguished between the dicotyledons, and the latter (grass-like) monocotyledon group, although he had no formal names for the two groups. Formal description dates from John Ray 's studies of seed structure in the 17th century. Ray, who is often considered the first botanical systematist , observed

1230-559: A smooth texture, and are fibrous, or with cellular reticulation. The inner coats of the bulbs are membranous. Many alliums have basal leaves that commonly wither away from the tips downward before or while the plants flower, but some species have persistent foliage. Plants produce from one to 12 leaves, most species having linear, channeled or flat leaf blades. The leaf blades are straight or variously coiled, but some species have broad leaves, including A. victorialis and A. tricoccum . The leaves are sessile , and very rarely narrowed into

1312-686: A synonym. Taxonomists had considerable latitude in naming this group, as the Monocotyledons were a group above the rank of family. Article 16 of the ICBN allows either a descriptive botanical name or a name formed from the name of an included family. In summary they have been variously named, as follows: Over the 1980s, a more general review of the classification of angiosperms was undertaken. The 1990s saw considerable progress in plant phylogenetics and cladistic theory, initially based on rbcL gene sequencing and cladistic analysis, enabling

1394-509: A typical inverted conical shape of the basal primary axis ( see Tillich, Figure 1). The limited conductivity also contributes to limited branching of the stems. Despite these limitations a wide variety of adaptive growth forms has resulted (Tillich, Figure 2) from epiphytic orchids (Asparagales) and bromeliads (Poales) to submarine Alismatales (including the reduced Lemnoideae ) and mycotrophic Burmanniaceae (Dioscreales) and Triuridaceae (Pandanales). Other forms of adaptation include

1476-629: A vegetable including the onion , garlic , scallions , shallots , leeks , and chives , with onions being the second most grown vegetable globally after tomatoes as of 2023. Allium species occur in temperate climates of the Northern Hemisphere , except for a few species occurring in Chile (such as A. juncifolium ), Brazil ( A. sellovianum ), and tropical Africa ( A. spathaceum ). They vary in height between 5–150 centimetres (2–59 in). The flowers form an umbel at

1558-725: A very short period in a plant's life), nor is it completely reliable. The single cotyledon is only one of a number of modifications of the body plan of the ancestral monocotyledons, whose adaptive advantages are poorly understood, but may have been related to adaption to aquatic habitats , prior to radiation to terrestrial habitats. Nevertheless, monocots are sufficiently distinctive that there has rarely been disagreement as to membership of this group, despite considerable diversity in terms of external morphology. However, morphological features that reliably characterise major clades are rare. Thus monocots are distinguishable from other angiosperms both in terms of their uniformity and diversity. On

1640-466: Is a broad sketch only, not invariably applicable, as there are a number of exceptions. The differences indicated are more true for monocots versus eudicots . A number of these differences are not unique to the monocots, and, while still useful, no one single feature will infallibly identify a plant as a monocot. For example, trimerous flowers and monosulcate pollen are also found in magnoliids , and exclusively adventitious roots are found in some of

1722-503: Is characterised by herbaceous geophyte perennials with true bulbs , some of which are borne on rhizomes , and an onion or garlic odor and flavor. The bulbs are solitary or clustered and tunicate and the plants are perennialized by the bulbs reforming annually from the base of the old bulbs, or are produced on the ends of rhizomes or, in a few species, at the ends of stolons . A small number of species have tuberous roots. The bulbs' outer coats are commonly brown or grey, with

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1804-613: Is found widely across mountain ranges Europe , as well as the Caucasus and the Himalayas . The specific epithet victorialis comes from the German Siegwurz (Root of Victory), and it earned this name having been "worn as an amulet, to be as safeguard against the attacks of certain impure spirits," by Bohemian miners among others. The plant, in past centuries in certain mountainous regions of Europe, "was cultivated as

1886-492: Is not accompanied by changes in ploidy level. This remarkable variation was noted in the discussion of the evolution of junk DNA and resulted in the Onion Test , a "reality check for anyone who thinks they have come up with a universal function for junk DNA". Genome sizes vary between 7.5 Gb in A. schoenoprasum and 30.9 Gb in A. ursinum , both of which are diploid . The unusual telomeric sequence of 'Allium cepa'

1968-468: Is one of the largest monocotyledonous genera, but the precise taxonomy of Allium is poorly understood, with incorrect descriptions being widespread. The difficulties arise from the fact that the genus displays considerable polymorphism and has adapted to a wide variety of habitats. Furthermore, traditional classifications had been based on homoplasious characteristics (the independent evolution of similar features in species of different lineages). However,

2050-524: Is one of the most popular and has been given an Award of Garden Merit (H4). These ornamental onions produce spherical umbels on single stalks in spring and summer, in a wide variety of sizes and colours, ranging from white ( Allium 'Mont Blanc'), blue ( A. caeruleum ), to yellow ( A. flavum ) and purple ( A. giganteum ). By contrast, other species (such as invasive A. triquetrum and A. ursinum ) can become troublesome garden weeds . The following cultivars, of uncertain or mixed parentage, have gained

2132-499: Is the name that has been most commonly used since the publication of the Angiosperm Phylogeny Group (APG) system in 1998 and regularly updated since. Within the angiosperms, there are two major grades , a small early branching basal grade, the basal angiosperms (ANA grade) with three lineages and a larger late branching grade, the core angiosperms (mesangiosperms) with five lineages, as shown in

2214-759: Is their growth pattern, lacking a lateral meristem ( cambium ) that allows for continual growth in diameter with height ( secondary growth ), and therefore this characteristic is a basic limitation in shoot construction. Although largely herbaceous, some arboraceous monocots reach great height, length and mass. The latter include agaves , palms , pandans , and bamboos . This creates challenges in water transport that monocots deal with in various ways. Some, such as species of Yucca , develop anomalous secondary growth, while palm trees utilise an anomalous primary growth form described as establishment growth ( see Vascular system ). The axis undergoes primary thickening, that progresses from internode to internode, resulting in

2296-683: Is usually fugacious (short lived). Some of the more persistent perigones demonstrate thermonastic opening and closing (responsive to changes in temperature). About two thirds of monocots are zoophilous , predominantly by insects . These plants need to advertise to pollinators and do so by way of phaneranthous (showy) flowers. Such optical signalling is usually a function of the tepal whorls but may also be provided by semaphylls (other structures such as filaments , staminodes or stylodia which have become modified to attract pollinators). However, some monocot plants may have aphananthous (inconspicuous) flowers and still be pollinated by animals. In these

2378-721: Is whose pulp is divided into two lobes and a radicle... 2. Such which neither spring out of the ground with seed leaves nor have their pulp divided into lobes John Ray (1674), pp. 164, 166 Since this paper appeared a year before the publication of Malpighi 's Anatome Plantarum (1675–1679), Ray has the priority. At the time, Ray did not fully realise the importance of his discovery but progressively developed this over successive publications. And since these were in Latin, "seed leaves" became folia seminalia and then cotyledon , following Malpighi . Malpighi and Ray were familiar with each other's work, and Malpighi in describing

2460-522: The Gilliesieae . The terminology has varied with some authors subdividing subgenera into Sections and others Alliances. The term Alliance has also been used for subgroupings within species, e.g. Allium nigrum , and for subsections. Subsequent molecular phylogenetic studies have shown the 2006 classification is a considerable improvement over previous classifications, but some of its subgenera and sections are probably not monophyletic . Meanwhile,

2542-593: The Piperaceae . Similarly, at least one of these traits, parallel leaf veins, is far from universal among the monocots. Broad leaves and reticulate leaf veins, features typical of dicots, are found in a wide variety of monocot families: for example, Trillium , Smilax (greenbriar), Pogonia (an orchid), and the Dioscoreales (yams). Potamogeton and Paris quadrifolia (herb-paris) are examples of monocots with tetramerous flowers. Other plants exhibit

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2624-754: The Royal Horticultural Society 's Award of Garden Merit : Dogs and cats are very susceptible to poisoning after the consumption of certain species. Even cattle have suffered onion toxicosis. Vegetables of the Allium genus can cause digestive disorders for human beings. The genus includes many economically important species. These include onions ( A. cepa ), French shallots ( A. oschaninii ), leeks ( A. ampeloprasum ), garlic ( A. sativum ), and herbs such as scallions (various Allium species) and chives ( A. schoenoprasum ). Some have been used as traditional medicines. This genus also includes species that are abundantly gathered from

2706-680: The boreal zone, predominantly in Asia. Of the latter, 138 species occur in China, about a sixth of all Allium species, representing five subgenera. A few species are native to Africa and Central and South America. A single known exception, Allium dregeanum occurs in the Southern Hemisphere (South Africa). There are two centres of diversity , a major one from the Mediterranean Basin to Central Asia and Pakistan , while

2788-450: The cladogram . Amborellales Nymphaeales Austrobaileyales magnoliids Chloranthales monocots Ceratophyllales eudicots While the monocotyledons have remained extremely stable in their outer borders as a well-defined and coherent monophylectic group, the deeper internal relationships have undergone considerable flux, with many competing classification systems over time. Historically, Bentham (1877), considered

2870-537: The dichotomy of cotyledon structure in his examination of seeds. He reported his findings in a paper read to the Royal Society on 17 December 1674, entitled "A Discourse on the Seeds of Plants". The greatest number of plants that come of seed spring at first out of the earth with two leaves which being for the most part of a different figure from the succeeding leaves are by our gardeners not improperly called

2952-440: The eudicots are the largest and most diversified angiosperm radiations , accounting for 22.8% and 74.2% of all angiosperm species respectively. Of these, the grass family (Poaceae) is the most economically important, which together with the orchids Orchidaceae account for half of the species diversity, accounting for 34% and 17% of all monocots respectively, and are among the largest families of angiosperms. They are also among

3034-405: The leek moth and onion fly as well as other Lepidoptera including cabbage moth , common swift moth (recorded on garlic), garden dart moth, large yellow underwing moth, nutmeg moth, setaceous Hebrew character moth, turnip moth and Schinia rosea , a moth that feeds exclusively on Allium species. The genus Allium has very large variation between species in their genome size that

3116-530: The lilioid monocots ; major cereal grains ( maize , rice , barley , rye , oats , millet , sorghum and wheat ) in the grass family ; and forage grasses ( Poales ) as well as woody tree-like palm trees ( Arecales ), bamboo , reeds and bromeliads (Poales), bananas and ginger ( Zingiberales ) in the commelinid monocots , as well as both emergent (Poales, Acorales ) and aroids , as well as floating or submerged aquatic plants such as seagrass ( Alismatales ). The most important distinction

3198-418: The phyletic system that superseded it in the late nineteenth century, based on an understanding of the acquisition of characteristics. He also made the crucial observation Ex hac seminum divisione sumum potest generalis plantarum distinctio, eaque meo judicio omnium prima et longe optima, in eas sci. quae plantula seminali sunt bifolia aut διλόβω, et quae plantula sem. adulta analoga. (From this division of

3280-471: The suffix -florae was replaced with -anae ( e.g. Alismatanae ) and the number of superorders expanded to ten with the addition of Bromelianae, Cyclanthanae and Pandananae. Molecular studies have both confirmed the monophyly of the monocots and helped elucidate relationships within this group. The APG system does not assign the monocots to a taxonomic rank, instead recognizing a monocots clade. However, there has remained some uncertainty regarding

3362-463: The type species for the genus is Allium sativum which means "cultivated garlic". The decision to include a species in the genus Allium is taxonomically difficult, and species boundaries are unclear. Estimates of the number of species are as low as 260, and as high as 979. In the APG III classification system , Allium is placed in the family Amaryllidaceae , subfamily Allioideae (formerly

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3444-733: The ability to increase the width of a stem ( secondary growth ) via the same kind of vascular cambium found in non-monocot woody plants . However, some monocots do have secondary growth; because this does not arise from a single vascular cambium producing xylem inwards and phloem outwards, it is termed "anomalous secondary growth". Examples of large monocots which either exhibit secondary growth, or can reach large sizes without it, are palms ( Arecaceae ), screwpines ( Pandanaceae ), bananas ( Musaceae ), Yucca , Aloe , Dracaena , and Cordyline . The monocots form one of five major lineages of mesangiosperms (core angiosperms), which in themselves form 99.95% of all angiosperms . The monocots and

3526-462: The angiosperms. Correlation with morphological criteria showed that the defining feature was not cotyledon number but the separation of angiosperms into two major pollen types, uniaperturate ( monosulcate and monosulcate-derived) and triaperturate (tricolpate and tricolpate-derived), with the monocots situated within the uniaperturate groups. The formal taxonomic ranking of Monoctyledons thus became replaced with monocots as an informal clade. This

3608-418: The capsule wall between the partitions of the locule. The seeds are black, and have a rounded shape. The terete or flattened flowering scapes are normally persistent. The inflorescences are umbels , in which the outside flowers bloom first and flowering progresses to the inside. Some species produce bulbils within the umbels, and in some species, such as Allium paradoxum , the bulbils replace some or all

3690-743: The clade of interest) divergence times in mya (million years ago). Acorales Alismatales Petrosaviales Dioscoreales (115 MYA) Pandanales (91 MYA) Allium victorialis Allium victorialis , commonly known as victory onion , Alpine leek , and Alpine broad-leaf allium is a broad-leaved Eurasian species of wild onion . It is a perennial of the Amaryllis family that occurs widely in mountainous regions of Europe and parts of Asia ( Caucasus and Himalayas ). Some authors consider certain East Asian and Alaskan populations as constituting subspecies platyphyllum within

3772-421: The climbing vines of Araceae (Alismatales) which use negative phototropism ( skototropism ) to locate host trees ( i.e. the darkest area), while some palms such as Calamus manan ( Arecales ) produce the longest shoots in the plant kingdom, up to 185 m long. Other monocots, particularly Poales , have adopted a therophyte life form . The cotyledon, the primordial Angiosperm leaf consists of

3854-484: The cotyledons were critical to the development of the plant, proof that Ray required for his theory. In his Methodus plantarum nova Ray also developed and justified the "natural" or pre-evolutionary approach to classification, based on characteristics selected a posteriori in order to group together taxa that have the greatest number of shared characteristics. This approach, also referred to as polythetic would last till evolutionary theory enabled Eichler to develop

3936-404: The dominant members of many plant communities. The monocots are one of the major divisions of the flowering plants or angiosperms. They have been recognized as a natural group since the sixteenth century when Lobelius (1571), searching for a characteristic to group plants by, decided on leaf form and their venation . He observed that the majority had broad leaves with net-like venation, but

4018-419: The exact relationships between the major lineages, with a number of competing models (including APG). The APG system establishes eleven orders of monocots. These form three grades, the alismatid monocots , lilioid monocots and the commelinid monocots by order of branching, from early to late. In the following cladogram numbers indicate crown group (most recent common ancestor of the sampled species of

4100-509: The family Alliaceae). In some of the older classification systems , Allium was placed in Liliaceae . Molecular phylogenetic studies have shown this circumscription of Liliaceae is not monophyletic . Various Allium have been cultivated from the earliest times, and about a dozen species are economically important as crops , or garden vegetables , and an increasing number of species are important as ornamental plants . Plants of

4182-440: The flowers. The umbels are subtended by noticeable spathe bracts, which are commonly fused and normally have around three veins. Some bulbous alliums increase by forming little bulbs or "offsets" around the old one, as well as by seed . Several species can form many bulbils in the flowerhead; in the so-called " tree onion " or Egyptian onion ( A. ×  proliferum ) the bulbils are few, but large enough to be pickled . Many of

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4264-541: The genus Allium in his Species Plantarum (1753), there were thirty species with this name. He placed Allium in a grouping he referred to as Hexandria monogynia (i.e. six stamens and one pistil ) containing 51 genera in all. Linnaeus originally grouped his 30 species into three alliances , e.g. Foliis caulinis planis . Since then, many attempts have been made to divide the growing number of recognised species into infrageneric subgroupings, initially as sections, and then as subgenera further divided into sections. For

4346-424: The genus has been shown to be monophyletic , containing three major clades , although some proposed subgenera are not. Some progress is being made using molecular phylogenetic methods, and the internal transcribed spacer (ITS) region, including the 5.8S rDNA and the two spacers ITS1 and ITS2, is one of the more commonly used markers in the study of the differentiation of the Allium species. Allium includes

4428-530: The genus produce chemical compounds, mostly derived from cysteine sulfoxides, that give them a characteristic onion or garlic taste and odor. Many are used as food plants, though not all members of the genus are equally flavorful. In most cases, both bulb and leaves are edible. The characteristic Allium flavor depends on the sulfate content of the soil the plant grows in. In the rare occurrence of sulfur-free growth conditions, all Allium species completely lose their usual pungency. The genus Allium (alliums)

4510-423: The group. Douglas E. Soltis and others identify thirteen synapomorphies (shared characteristics that unite monophyletic groups of taxa); Monocots have a distinctive arrangement of vascular tissue known as an atactostele in which the vascular tissue is scattered rather than arranged in concentric rings. Collenchyma is absent in monocot stems, roots and leaves. Many monocots are herbaceous and do not have

4592-403: The largest subgenus of the genus Allium : subgenus Allium , which includes the type species of the genus, Allium sativum . This subgenus also contains the majority of the species in its lineage. Within the lineage, the phylogeny is complex. Two small subgenera, Butomissa and Cyathophora form a sister clade to the remaining five subgenera, with Butomissa as the first branching group. Amongst

4674-464: The leaf veins emerging at the leaf base and then running together at the apices. There is usually only one leaf per node because the leaf base encompasses more than half the circumference. The evolution of this monocot characteristic has been attributed to developmental differences in early zonal differentiation rather than meristem activity (leaf base theory). The lack of cambium in the primary root limits its ability to grow sufficiently to maintain

4756-417: The majority of the biomass produced comes from monocotyledons. These include not only major grains ( rice , wheat , maize , etc.), but also forage grasses, sugar cane , the bamboos , and many other common food and decorative crops. The monocots or monocotyledons have, as the name implies, a single (mono-) cotyledon , or embryonic leaf, in their seeds . Historically, this feature was used to contrast

4838-419: The monocots to consist of four alliances , Epigynae, Coronariae, Nudiflorae and Glumales, based on floral characteristics. He describes the attempts to subdivide the group since the days of Lindley as largely unsuccessful. Like most subsequent classification systems it failed to distinguish between two major orders, Liliales and Asparagales , now recognised as quite separate. A major advance in this respect

4920-408: The monocots with the dicotyledons or dicots which typically have two cotyledons; however, modern research has shown that the dicots are not a natural group, and the term can only be used to indicate all angiosperms that are not monocots and is used in that respect here. From a diagnostic point of view the number of cotyledons is neither a particularly useful characteristic (as they are only present for

5002-456: The number of new species continued to increase, reaching 800 by 2009, and the pace of discovery has not decreased. Detailed studies have focused on a number of subgenera, including Amerallium . Amerallium is strongly supported as monophyletic. Subgenus Melanocrommyum has also been the subject of considerable study (see below), while work on subgenus Allium has focussed on section Allium , including Allium ampeloprasum , although sampling

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5084-400: The one hand that the monocots remained as a well defined monophyletic group or clade , in contrast to the other historical divisions of the flowering plants, which had to be substantially reorganized. No longer could the angiosperms be simply divided into monocotyledons and dicotyledons; it was apparent that the monocotyledons were but one of a relatively large number of defined groups within

5166-520: The one hand, the organization of the shoots, leaf structure, and floral configuration are more uniform than in the remaining angiosperms, yet within these constraints a wealth of diversity exists, indicating a high degree of evolutionary success. Monocot diversity includes perennial geophytes such as ornamental flowers including orchids ( Asparagales ); tulips and lilies ( Liliales ); rosette and succulent epiphytes (Asparagales); mycoheterotrophs (Liliales, Dioscoreales , Pandanales ), all in

5248-511: The plant. This necessitates early development of roots derived from the shoot (adventitious roots). In addition to roots, monocots develop runners and rhizomes , which are creeping shoots. Runners serve vegetative propagation , have elongated internodes , run on or just below the surface of the soil and in most case bear scale leaves . Rhizomes frequently have an additional storage function and rhizome producing plants are considered geophytes (Tillich, Figure 11). Other geophytes develop bulbs ,

5330-535: The plants rely either on chemical attraction or other structures such as coloured bracts fulfill the role of optical attraction. In some phaneranthous plants such structures may reinforce floral structures. The production of fragrances for olfactory signalling are common in monocots. The perigone also functions as a landing platform for pollinating insects. The embryo consists of a single cotyledon, usually with two vascular bundles . The traditionally listed differences between monocots and dicots are as follows. This

5412-407: The remaining five subgenera, Rhizirideum forms a medium-sized subgenus that is the sister to the other four, larger, subgenera. This line may not be monophyletic. Names from Some sources refer to Greek ἀλέω (aleo, to avoid) due to the odor of garlic. The majority of Allium species are native to the Northern Hemisphere , being spread throughout the holarctic region, from dry subtropics to

5494-482: The same structures had introduced the term cotyledon, which Ray adopted in his subsequent writing. Mense quoque Maii, alias seminales plantulas Fabarum, & Phaseolorum, ablatis pariter binis seminalibus foliis, seu cotyledonibus, incubandas posui In the month of May, also, I incubated two seed plants, Faba and Phaseolus , after removing the two seed leaves, or cotyledons Marcello Malpighi (1679), p. 18 In this experiment, Malpighi also showed that

5576-425: The seed leaves... In the first kind the seed leaves are nothing but the two lobes of the seed having their plain sides clapt together like the two halves of a walnut and therefore are of the just figure of the seed slit in sunder flat wise... Of seeds that spring out of the earth with leaves like the succeeding and no seed leaves I have observed two sorts. 1. Such as are congenerous to the first kind precedent that

5658-400: The seeds derives a general distinction amongst plants, that in my judgement is first and by far the best, into those seed plants which are bifoliate, or bilobed, and those that are analogous to the adult), that is between monocots and dicots. He illustrated this by quoting from Malpighi and including reproductions of Malpighi's drawings of cotyledons (see figure). Initially Ray did not develop

5740-445: The soil, these are geophilous shoots (Tillich, Figure 11) that help overcome the limited trunk stability of large woody monocots. In nearly all cases the perigone consists of two alternating trimerous whorls of tepals , being homochlamydeous , without differentiation between calyx and corolla . In zoophilous (pollinated by animals) taxa, both whorls are corolline (petal-like). Anthesis (the period of flower opening)

5822-430: The species Allium victorialis . Recent sources recognize this group as a distinct species, called Allium ochotense . Allium victorialis attains a height of 30–45 cm (11.8–17.7 in) and forms a sheathed bulb ("root-stalk") about the thickness of a finger and 5–8 cm (2.0–3.1 in) long. Leaves are broad, elliptical or lanceolate. Flowers ( perianths ) are whitish green. Allium victorialis

5904-404: The species are attributed to subgenus Amerallium , the third largest subgenus of Allium . The lineage is considered to represent the most ancient line within Allium , and to be the only lineage that is purely bulbous, the other two having both bulbous and rhizomatous taxa. Within the lineage Amerallium is a sister group to the other two subgenera ( Microscordum + Nectaroscordum ). Nearly all

5986-409: The species in this lineage of five subgenera are accounted for by subgenus Melanocrommyum , which is most closely associated with subgenera Vvedenskya and Porphyroprason , phylogenetically. These three genera are late-branching whereas the remaining two subgenera, Caloscordum and Anguinum , are early branching. The third evolutionary line contains the greatest number of sections (seven), and also

6068-619: The species of Allium have been used as food items throughout their ranges. There are several unrelated species that are somewhat similar in appearance to Alliums but are poisonous (e.g. in North America, death camas, Toxicoscordion venenosum ), but none of these has the distinctive scent of onions or garlic. With over 850 species Allium is the sole genus in the Allieae , one of four tribes of subfamily Allioideae ( Amaryllidaceae ). New species continue to be described and Allium

6150-403: The specific issue regarding Liliales and Asparagales, Dahlgren followed Huber (1969) in adopting a splitter approach, in contrast to the longstanding tendency to view Liliaceae as a very broad sensu lato family . Following Dahlgren's untimely death in 1987, his work was continued by his widow, Gertrud Dahlgren , who published a revised version of the classification in 1989. In this scheme

6232-490: The term was used shortly after his classification appeared (1753) by Scopoli and who is credited for its introduction. Every taxonomist since then, starting with De Jussieu and De Candolle , has used Ray's distinction as a major classification characteristic. In De Jussieu's system (1789), he followed Ray, arranging his Monocotyledones into three classes based on stamen position and placing them between Acotyledones and Dicotyledones. De Candolle's system (1813) which

6314-429: The top of a leafless stalk. The bulbs vary in size between species, from small (around 2–3 mm in diameter) to rather large (8–10 cm). Some species (such as Welsh onion A. fistulosum and leeks ( A. ampeloprasum )) develop thickened leaf-bases rather than forming bulbs as such. Carl Linnaeus first described the genus Allium in 1753. The generic name Allium is the Latin word for garlic, and

6396-488: The wild such as wild garlic ( Allium ursinum ) in Europe and ramps ( Allium tricoccum ) in North America. Monocotyledon Monocotyledons have almost always been recognized as a group, but with various taxonomic ranks and under several different names. The APG III system of 2009 recognises a clade called "monocots" but does not assign it to a taxonomic rank. The monocotyledons include about 70,000 species, about

6478-682: Was discovered and cytologically validated to be CTCGGTTATGGG A bioinformatics method for detecting this unique telomere sequence was demonstrated using SERF de novo Genome Analysis Many Allium species have been harvested through human history, but only about a dozen are still economically important today as crops or garden vegetables . Many Allium species and hybrids are cultivated as ornamentals . These include A. cristophii and A. giganteum , which are used as border plants for their ornamental flowers, and their "architectural" qualities. Several hybrids have been bred, or selected, with rich purple flowers. A. hollandicum 'Purple Sensation'

6560-645: Was not sufficient to test the monophyly of the section. The major evolutionary lineages or lines correspond to the three major clades. Line one (the oldest) with three subgenera is predominantly bulbous, the second, with five subgenera and the third with seven subgenera contain both bulbous and rhizomatous taxa. The three evolutionary lineages and 15 subgenera here represent the classification schemes of Friesen et al. (2006) and Li (2010), and subsequent additional species and revisions. First evolutionary line Second evolutionary line Third evolutionary line Although this lineage consists of three subgenera, nearly all

6642-559: Was the work of Rolf Dahlgren (1980), which would form the basis of the Angiosperm Phylogeny Group 's (APG) subsequent modern classification of monocot families. Dahlgren who used the alternate name Lilliidae considered the monocots as a subclass of angiosperms characterised by a single cotyledon and the presence of triangular protein bodies in the sieve tube plastids . He divided the monocots into seven superorders , Alismatiflorae, Ariflorae, Triuridiflorae, Liliiflorae , Zingiberiflorae, Commeliniflorae and Areciflorae. With respect to

6724-468: Was to predominate thinking through much of the 19th century used a similar general arrangement, with two subgroups of his Monocotylédonés (Monocotyledoneae). Lindley (1830) followed De Candolle in using the terms Monocotyledon and Endogenae interchangeably. They considered the monocotyledons to be a group of vascular plants ( Vasculares ) whose vascular bundles were thought to arise from within ( Endogènes or endogenous ). Monocotyledons remained in

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