Trifolium repens

Last updated

White clover
Trifolium repens - white clover on way from Govindghat to Gangria at Valley of Flowers National Park - during LGFC - VOF 2019 (1).jpg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Genus: Trifolium
Species:
T. repens
Binomial name
Trifolium repens
L.
Synonyms [1]
Synonymy
  • Amoria repens(L.) C.Presl
  • Lotodes repensKuntze
  • Trifolium limoniumPhil.
  • Trifolium stipitatumClos
  • Trifolium macrorrhizumBoiss., syn of subsp. macrorrhizum
  • Trifolium nevadenseBoiss., syn of var. nevadense
  • Trifolium orbelicumVelen., syn of var. orbelicum
  • Trifolium orphanideumBoiss., syn of var. orphanideum
  • Trifolium biasolettiiSteud. & Hochst., syn of subsp. prostratum
  • Trifolium occidentaleCoombe, syn of subsp. prostratum

Trifolium repens, the white clover, is a herbaceous perennial plant in the bean family Fabaceae (otherwise known as Leguminosae). It is native to Europe, including the British Isles, [2] and central Asia and is one of the most widely cultivated types of clover. It has been widely introduced worldwide as a forage crop, and is now also common in most grassy areas (lawns and gardens) of North America, Australia and New Zealand. [3] [4] [5] [6] [7] [8] [9] The species includes varieties often classed as small, intermediate and large, according to height, which reflects petiole length. The term 'white clover' is applied to the species in general, 'Dutch clover' is often applied to intermediate varieties (but sometimes to smaller varieties), and 'ladino clover' is applied to large varieties. [10] [11] [12] [13]

Contents

Name

79 Trifolium repens L.jpg
2020 year. Herbarium. Clover. img-001.jpg
Flowering Starr 070313-5645 Trifolium repens.jpg
Flowering
4-leaf clover.JPG
Flower Trifolium repens White Clover, Dutch Clover at Thimphu during LGFC - Bhutan 2019 (1).jpg
Flower

The genus name, Trifolium , derives from the Latin tres , "three", and folium , "leaf", so called from the characteristic form of the leaf, which almost always has three leaflets (trifoliolate); hence the popular name "trefoil". The species name, repens , is Latin for "creeping".

Description

It is a herbaceous, perennial plant. It is low growing, with flowering heads of whitish florets, often with a tinge of pink or cream that may come on with the aging of the plant. The heads are generally 1.5–2 centimetres (1234 in) wide, and are at the end of 7 centimetres (2+34 in) peduncles or inflorescence stalks. [14] The flowers are mostly visited by bumblebees [15] and often by honey bees. The leaves are trifoliolate, smooth, elliptic to egg-shaped and long-petioled and usually with light or dark markings. The stems function as stolons, so white clover often forms mats, with the stems creeping as much as 18 cm (7 in) a year, and rooting at the nodes. [14] The leaves form the symbol known as shamrock. Almost always, a white clover will be trifoliolate. However, one can, but only sometimes, possess four or more leaflets.[ citation needed ]

Varieties and subspecies

Distribution

It is native in Europe and Central Asia, ubiquitous throughout the British Isles, [16] introduced in North America, South Africa, Australia, New Zealand, Japan and elsewhere, and globally cultivated as a forage crop.

White clover has been used as a model organism for global research into ecology and urban evolution. As part of the Global Urban Evolution Project (GLUE) scientists from 26 countries examined the production of cyanide by over 110,000 clover plants from 160 cities. Cyanide can be useful to clover plants as a deterrent to herbivores. Analyzing urban-rural differences, scientists found that cyanide production tended to increase with distance from the center of cities, suggesting that clover populations were adapting to factors commonly found in urban centers worldwide. Possible factors could include temperature (freezing is related to cyanide content), herbivory pressures, and drought stress. As clover habitats, the downtowns of cities may more closely resemble other far-flung cities than nearby rural areas. [17] [18] [19]

Ancestry

Trifolium repens is an allotetraploid (2n = 4x = 32) of two diploid ancestors and exhibits disomic inheritance. [20] In order to increase genetic diversity for breeding, research is focused on finding these ancestors. Proposed ancestors of T. repens include T. nigrescens , T. occidentale , T. pallescens , and T. uniflorum . [20] [21] [22] [23] Additionally, it is possible that one of the diploid ancestors has yet to be analyzed, either because it has not been discovered or is extinct. [24]

Cultivation and uses

Forage

White clover has been described as the most important forage legume of the temperate zones. [25] Symbiotic nitrogen fixation (up to 545 kilograms per hectare per year (486 lb/acre/a) of N, [26] although usually much less, e.g. about 110 to 170 kilograms per hectare per year (98 to 152 lb/acre/a) [27] ) in root nodules of white clover obviates synthetic nitrogen fertilizer use for maintaining productivity on much temperate zone pasture land. White clover is commonly grown in mixtures with forage grasses, e.g. perennial ryegrass ( Lolium perenne ). [28] [29] [30] Such mixtures can not only optimize livestock production, but can also reduce the bloat risk to livestock that can be associated with excessive white clover in pastures. [31] Such species mixtures also tend to avoid issues that could otherwise be associated with cyanogenic glycosides (linamarin and lotaustralin) intake on pure or nearly pure stands of some white clover varieties. [32] However, problems do not inevitably arise with grazing on monocultures of white clover, and superior ruminant production is sometimes achieved on white clover monocultures managed to optimize sward height. [33]

The O-methylated isoflavones formononetin and biochanin A play a role in arbuscular mycorrhiza formation on white clover roots, [34] and foliar disease can stimulate production of estrogenic coumestans in white clover. [35] However, while there have been a few reports of phytoestrogenic effects of white clover on grazing ruminants, [35] these have been far less common than such reports regarding some varieties of subterranean clover ( Trifolium subterraneum ) and red clover ( Trifolium pratense ). Among forage plants, some white clover varieties tend to be favored by rather close grazing, because of their stoloniferous habit, [36] [37] which can contribute to competitive advantage.

Companion planting, green manure, and cover crops

White clover grows well as a companion plant among lawns, grain crops, pasture grasses, and vegetable rows. [14] It is often added to lawn seed mixes, as it is able to grow and provide green cover in poorer soils where turfgrasses do not perform well. White clover can tolerate close mowing and grazing, and it can grow on many different types and pHs of soil (although it prefers clay soils). [14] As a leguminous and hardy plant, it is considered to be a beneficial component of natural or organic pasture management and lawn care due to its ability to fix nitrogen and out-compete weeds. Natural nitrogen fixing reduces leaching from the soil and by maintaining soil health can reduce the incidence of some lawn diseases that are enhanced by the availability of synthetic fertilizer. [38] For these reasons, it is often used as a green manure and cover crop.

Culinary uses

Besides making an excellent forage crop for livestock, [39] its leaves and flowers are a valuable survival food: they are high in proteins, and are widespread and abundant. The fresh plants have been used for centuries as additives to salads and other meals consisting of leafy vegetables.[ citation needed ] They are not easy for humans to digest raw, but, this is however easily fixed by boiling the harvested plants for 5–10 minutes. [40] Native Americans ate some species raw. [41] Dried white clover flowers may also be smoked as a herbal alternative to tobacco. [42]

Medicinal uses

In India, T. repens is considered a folk medicine against intestinal helminthic worms, and an experimental in-vivo study validated that the aerial shoots of T. repens bear significant anticestodal (anti-tapeworm) properties. [43]

Etymology

Trifolium means 'trefoil' (three-lobed leaves); this is Pliny’s name for trifoliate plants. [44]

Repens means 'creeping' or 'stoloniferous'. [44]

Related Research Articles

<span class="mw-page-title-main">Clover</span> Genus of legumes

Clover, also called trefoil, are plants of the genus Trifolium, consisting of about 300 species of flowering plants in the legume family Fabaceae originating in Europe. The genus has a cosmopolitan distribution with highest diversity in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes on mountains in the tropics. They are small annual, biennial, or short-lived perennial herbaceous plants, typically growing up to 30 centimetres (12 in) tall. The leaves are trifoliate, with stipules adnate to the leaf-stalk, and heads or dense spikes of small red, purple, white, or yellow flowers; the small, few-seeded pods are enclosed in the calyx. Other closely related genera often called clovers include Melilotus and Medicago.

<i>Onobrychis</i> Genus of flowering plants in the bean family Fabaceae

Onobrychis, the sainfoins, are a genus of Eurasian perennial herbaceous plants of the legume family (Fabaceae). About 206 species are presently accepted. The Flora Europaea lists 23 species of Onobrychis; the main centre of diversity extends from Central Asia to Iran, with 56 species – 27 of which are endemic – in the latter country alone. O. viciifolia is naturalized throughout many countries in Europe and North America grasslands on calcareous soils.

<span class="mw-page-title-main">Forage</span> Plant material eaten by grazing livestock

Forage is a plant material eaten by grazing livestock. Historically, the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially as hay or silage.

<i>Lolium</i> Genus of plants (tufted grasses)

Lolium is a genus of tufted grasses in the bluegrass subfamily (Pooideae). It is often called ryegrass, but this term is sometimes used to refer to grasses in other genera.

<i>Trifolium pratense</i> Species of flowering plant in the bean family

Trifolium pratense, red clover, is a herbaceous species of flowering plant in the bean family Fabaceae, native to Europe, Western Asia, and northwest Africa, but planted and naturalized in many other regions.

<i>Trifolium arvense</i> Species of flowering plant in the bean family Fabaceae

Trifolium arvense, commonly known as the hare's-foot clover, rabbitfoot clover, stone clover or oldfield clover, is a flowering plant in the bean family Fabaceae. This species of clover is native to most of Europe, excluding the Arctic zone, and western Asia, in plain or mid-mountain habitats up to 1,600 metres (5,200 ft) altitude. It grows in dry sandy soils, both acidic and alkaline, soil with dry-mesic conditions and is typically found at the edge of fields, in wastelands, at the side of roads, on sand dunes, and opportunistically in vineyards and orchards when they are not irrigated.

<span class="mw-page-title-main">Living mulch</span> Cover crop grown with a main crop as mulch

In agriculture, a living mulch is a cover crop interplanted or undersown with a main crop, and intended to serve the purposes of a mulch, such as weed suppression and regulation of soil temperature. Living mulches grow for a long time with the main crops, whereas cover crops are incorporated into the soil or killed with herbicides.

<i>Lolium perenne</i> Species of plant

Lolium perenne, common name perennial ryegrass, English ryegrass, winter ryegrass, or ray grass, is a grass from the family Poaceae. It is native to Europe, Asia and northern Africa, but is widely cultivated and naturalised around the world.

<i>Lolium pratense</i> Species of grass

Lolium pratense, meadow fescue is a perennial species of grass, which is often used as an ornamental in gardens, and is also an important forage crop. It grows in meadows, roadsides, old pastures, and riversides on moist, rich soils, especially on loamy and heavy soils.

<i>Medicago lupulina</i> Species of flowering plant in the bean family Fabaceae

Medicago lupulina, commonly known as black medick, nonesuch, or hop clover, is a plant of dry grassland belonging to the legume or clover family. Plants of the genus Medicago, or bur clovers, are closely related to the true clovers (Trifolium) and sweet clover (Melilotus). Like the true clovers, black medick has three leaflets and a small, yellow flower closely resembling those of lesser trefoil. Black medick belongs to the same genus as alfalfa.

British NVC community MG6 is one of the mesotrophic grassland communities in the British National Vegetation Classification system. It is one of four such communities associated with well-drained permanent pastures and meadows.

British NVC community MG4 is one of the mesotrophic grassland communities in the British National Vegetation Classification system. It is one of four such communities associated with well-drained permanent pastures and meadows.

<i>Trifolium hybridum</i> Species of flowering plant in the bean family

Trifolium hybridum, the alsike clover, is a species of flowering plant in the pea family Fabaceae. The stalked, pale pink or whitish flower head grows from the leaf axils, and the trifoliate leaves are unmarked. The plant is up to 40 centimetres (1.3 ft) tall, and is found in fields and on roadsides – it is also grown as fodder. It has been linked with toxicity in horses and has some agricultural uses. The plant blooms from spring to autumn. Originating in mainland Europe, it has become established as an introduced plant in the British Isles and throughout the temperate regions of the world.

<i>Lolium arundinaceum</i> Species of flowering plant

Lolium arundinaceum, tall fescue is a cool-season perennial C3 species of grass that is native to Europe. It occurs on woodland margins, in grassland and in coastal marshes. It is also an important forage grass with many cultivars that used in agriculture and is used as an ornamental grass in gardens, and sometimes as a phytoremediation plant.

<i>Lolium multiflorum</i> Species of flowering plant

Lolium multiflorum is a ryegrass native to temperate Europe, though its precise native range is unknown.

Pythiumdisease, also known as "Pythiumblight," "cottony blight," or "grease spot," is a highly destructive turfgrass disease caused by several different Pythium species. All naturally cultivated cool-season turfgrasses are susceptible to Pythium and if conditions are favorable to Pythium it can destroy a whole turfgrass stand in a few days or less. Pythium favors hot and very humid weather and will usually develop in low areas or swales in the turfgrass.

<i>Lolium rigidum</i> Species of grass

Lolium rigidum is a species of annual grass. Common names by which it is known include annual ryegrass, a name also given to Italian ryegrass, rigid ryegrass, stiff darnel, Swiss ryegrass and Wimmera ryegrass. It is a native of southern Europe, northern Africa, the Middle East and the Indian subcontinent and is grown as a forage crop, particularly in Australia, where it is also a serious and economically damaging crop weed.

Perennial ryegrass staggers is poisoning by peramine, lolitrem B, and other toxins that are contained in perennial ryegrass, and produced by the endophyte fungus Epichloë festucae which can be present in all parts of the grass plant, but tends to be concentrated in the lower part of the leaf sheaths, the flower stalks and seeds. This condition can affect horses, cattle, sheep, farmed deer and llamas. It regularly occurs in New Zealand and is known spasmodically from Australia, North and South America, and Europe.

<span class="mw-page-title-main">Lolitrem B</span> Chemical compound

Lolitrem B is one of many toxins produced by a fungus called Epichloë festucae var. lolii), which grows in Lolium perenne. The fungus is symbiotic with the ryegrass; it doesn't harm the plant, and the toxins it produces kill insects that feed on ryegrass. Lolitrem B is one of these toxins, but it is also harmful to mammals. The shoots and flowers of infected ryegrass have especially high concentrations of lolitrem B, and when livestock eat too much of them, they get perennial ryegrass staggers. At low doses the animals have tremors, and at higher doses they stagger, and at higher yet doses the animals become paralyzed and die. The blood pressure of the animals also goes up. The effect of the lolitrem B comes on slowly and fades out slowly, as it is stored in fat after the ryegrass is eaten. The condition is especially common in New Zealand and Australia, and plant breeders there have been trying to develop strains of fungus that produce toxins only harmful to pests, and not to mammals.

A pasture wedge graph or feed wedge is a farm management tool used by dairy farmers for the purposes of managing pasture. It takes the form of a bar graph, that shows the amount of feed available in a pasture over time, and is therefore shaped as a declining wedge.

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Bibliography