Cuscuta campestris | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Solanales |
Family: | Convolvulaceae |
Genus: | Cuscuta |
Species: | C. campestris |
Binomial name | |
Cuscuta campestris | |
Cuscuta campestris, with the common names field dodder, golden dodder, large-seeded alfalfa dodder, yellow dodder and prairie dodder, is a parasitic plant which belongs to the family Convolvulaceae. It was formerly classified in the family Cuscutaceae.
It is native to central North America. It is a parasite of a wide range of herbaceous plants.
It is a pest of lucerne and other legumes. It has become a widespread weed in many countries. It is known as 'golden dodder' in Australia.
It has been confused in some recent literature with Cuscuta pentagona Engelmann, but the differences between the two species are clear. [2]
Remarkably, the seeds of the plant have been found to become dispersed by waterfowl in significant numbers. [3]
The life cycle of the Cuscuta starts with seed germination. The seeds germinate near the surface of the soil, sending up thin stems in colors of pale green and yellow. [4] The thread-like stems grow slowly until they touch another plant and begin to wrap themselves around it. Once fully wrapped around a host plant, Cuscuta campestris will form sucker-like roots, called haustoria, and penetrate the body of the host, stealing nutrients from them. [5] Once attached, the lowest end of the Cuscuta campestris plant will die and lose its connection with the ground's surface. If the seedlings do not make contact with a host plant, they will die. [6] The seedlings cannot survive for long periods of time hence, they find the appropriate plant stem by recognizing plant chemo-attractants. Cuscuta campestris is known for restraining the growth of their host plants and even inhibiting their flowering. This causes the host cell to eventually die. [7] This mechanism gives them the ability to control other populations of weeds like Mikania micrantha. [8] Another mechanism by which these dodders recognize which plants to use as hosts depends on the light that's reflected off the plant's surface. Cuscuta campestris is highly attracted to "far red light", which is a wavelength that is reflected by most plant surfaces. Dodders that were exposed to unfiltered light were able to attach to their host before their energy had been totally exhausted, but dodders that were only exposed to red light lost their way. This could be a technique by which to control C. campestris infestations if exposed to red light within the early stages of development, to avoid the spread and growth of the plant. [9] Cuscuta campestris is a parasitic weed that is one of the most widespread. [10] It does not contain leaves or roots and must grow an absorptive organ as an interconnecting vessel between itself and the host plant. [10] These absorptive organs allow for Cuscuta Campestris to penetrate the tissue of the host plant and connect, drawing out nutrients from the host. [11] Cuscuta spp. can simultaneously parasitize many plants at the same time, suggesting that the species have a foraging technique that has evolved throughout history. [11]
The native range of this species is unknown but thought to be native to North America, specifically Canada, US, and Mexico. It is also found in parts of the Caribbean, including Cuba, Bahamas, Jamaica, Martinique, and possibly parts of South America. [6] It is widely naturalised in parts of coastal and subcoastal regions of Australia, being found predominantly in the Southeastern Australia border along the Murray River. [6] Cuscuta campestris can be found growing in grasslands, open woodlands, gardens, riparian zones, and wetlands. [6] Cuscuta campestris has a tolerance for a wide range of climatic conditions, from warm temperate regions to subtropical or tropical regions. [12]
Reproduction takes place through seed or vegetative spread. Pollination for C. campestris is autogamous, or self-fertilizing, and the species can produce up to 16,000 seeds on a single plant. [12] In North America, flowering occurs in mid-summer, with less flowering occurring in humid, high rainfall locations. C. campestris seeds have a hard seed coating that requires degradation and scarification, reducing the danger of all seeds germinating at once. [13] Germination can occur regardless of the amount of light available, as long as temperatures are between 10-30 degrees celsius and the seeds are able to remain viable for up to 10 years in soil. [12]
Cuscuta campestris is an agricultural pest. By combining preventative, chemical, mechanical, and cultural methods, the populations of Cuscuta campestris can be reduced. [5] Scattered infestations can be dealt with using a hand-held flame gun, hand-pulling the host plants up with the Cuscuta campestris parasite species attached, or by mowing with a shallow blade. [6] Cuscuta campestris must be controlled on vegetation located on roadsides and sidewalks. [6] Cuscuta campestris is mainly spread by people, the best method is to educate people on the species and discourage them from carrying the plants to other locations. [6]
Preventative Management includes planting dodder-free crop seeds, cleaning agricultural machinery before each use, and managing pre-existing populations to reduce seed dispersal. [5] While small infestations can be removed by hand-pulling, the recommendation for controlling large infestations is to remove all host plants of the species and replace them with non-host species. [5] Field Dodder can be controlled using post-emergence herbicides, which are applied before the Cuscuta campestris emergence, and pre-emergence herbicides, which are applied after the Cuscuta campestris emergence. [5] Cultural control is another method for removing Field Dodder from an area, planting non-host crops, such as wheat, broccoli, corn, sorghum, and legumes can significantly reduce their presence. [5] Attempts to control C. campestris using a biological control, entail using gall forming weevils (Smicronyx spp.) and Agromyzid Flies (Melanagromyzacuscutae spp.), or using a pathogen, Alternaria cuscutacidae, has been successfully applied for population control. [12] Once cleared, areas with a history of Field dodder infestation should be watched extensively for more emergences. [5]
Parasitic plants of the genus Cuscuta have little to no chlorophyll making them unable to undergo photosynthesis, a process by which plants make their own food. This makes them photosynthetically inactive. [14] Cuscuta species are thus referred to as holoparasitic plants, as they depend on their host plant for nutrients. About 10-15 species of Cuscuta, out of the known 200, are considered agricultural weeds which wrap their vines around their hosts and obtain their nutrients from them through their extensions called haustoria. This mechanism for obtaining their food makes them very difficult to remove. Their growth has been cited to cause severe loss to crops that yield alfalfa, tomatoes, carrots and cranberry crops.[ citation needed ]
The life cycle of the Cuscuta starts with seed germination. The seedlings cannot survive for long periods of time hence, they find the appropriate plant stem by recognizing plant chemo-attractants. Cuscuta campestris is known for restraining the growth of their host plants and even inhibiting their flowering. This causes[ clarification needed ] the host cell to eventually die. [7] This mechanism gives them the ability to control other populations of weeds like Mikania micrantha. [15] Another mechanism by which these dodders recognize which plants to use as hosts depends on the light that's reflected off the plant's surface. Cuscuta campestris is highly attracted to "far red light", which is a wavelength that is reflected by most plant surfaces. Dodders that were exposed to unfiltered light were able to attach to their host before their energy had been totally exhausted, but dodders that were only exposed to red light lost their way. This could be a technique by which to control C. campestris infestations if exposed to red light within the early stages of development, to avoid the spread and growth of the plant. [14]
Cuscuta, commonly known as dodder or amarbel, is a genus of over 201 species of yellow, orange, or red parasitic plants. Formerly treated as the only genus in the family Cuscutaceae, it now is accepted as belonging in the morning glory family, Convolvulaceae, on the basis of the work of the Angiosperm Phylogeny Group. The genus is found throughout the temperate and tropical regions of the world, with the greatest species diversity in subtropical and tropical regions; the genus becomes rare in cool temperate climates, with only four species native to northern Europe.
Striga, commonly known as witchweed, is a genus of parasitic plants that occur naturally in parts of Africa, Asia, and Australia. It is currently classified in the family Orobanchaceae, although older classifications place it in the Scrophulariaceae. Some species are serious pathogens of cereal crops, with the greatest effects being in savanna agriculture in Africa. It also causes considerable crop losses in other regions, including other tropical and subtropical crops in its native range and in the Americas. The generic name derives from Latin strī̆ga, "witch".
Cassytha is a genus of some two dozen species of obligately parasitic vines in the family Lauraceae. Superficially, and in some aspects of their ecology, they closely resemble plants in the unrelated genus Cuscuta, the dodders. When fruit and flowers are absent in the field, the physical resemblance is so close that few people without technical training can discern the difference. In this respect and in their ecology the two genera present a spectacular example of convergent evolution. Nonetheless, Nickrent comments that "Cassytha is uneqivocally assigned to Lauraceae based on (both) morphological and molecular data." In its divergence from habits typical of the Lauraceae, Cassytha also presents examples of mosaic evolution
Phoradendron is a genus of mistletoe, native to warm temperate and tropical regions of the Americas. The center of diversity is the Amazon rainforest. Phoradendron is the largest genus of mistletoe in the Americas, and possibly the largest genus of mistletoes in the world. Traditionally, the genus has been placed in the family Viscaceae, but recent genetic research acknowledged by the Angiosperm Phylogeny Group shows this family to be correctly placed within a larger circumscription of the sandalwood family, Santalaceae.
A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called the haustorium, which penetrates the host plant, connecting them to the host vasculature – either the xylem, phloem, or both. For example, plants like Striga or Rhinanthus connect only to the xylem, via xylem bridges (xylem-feeding). Alternately, plants like Cuscuta and some members of Orobanche connect to both the xylem and phloem of the host. This provides them with the ability to extract resources from the host. These resources can include water, nitrogen, carbon and/or sugars. Parasitic plants are classified depending on the location where the parasitic plant latches onto the host, the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given off by host shoots or roots, respectively. About 4,500 species of parasitic plants in approximately 20 families of flowering plants are known.
Orobanche aegyptiaca, the Egyptian broomrape, is a plant which is an obligate holoparasite from the family Orobanchaceae with a complex lifecycle. This parasite is most common in the Middle East and has a wide host range including many economically important crops.
Cuscuta californica is a species of dodder known by the common names chaparral dodder and California dodder. This is an annual parasitic plant that may resemble fine strands of spaghetti or twine strewn across other species in its habitat. A mature plant of this species may fulfill all of its food and water needs from the host plant, but they rarely kill their host. It is native to western United States and Baja California in Mexico.
Cuscuta europaea, the greater dodder or European dodder, is a parasitic plant native to Europe, which belongs to the family Convolvulaceae, but was formerly classified in the family Cuscutaceae. It grows on Asteraceae, Cannabaceae, Chenopodiaceae, Fabaceae, Urticaceae and other herbaceous plants, including garden plants such as Coleus and Impatiens, and more occasionally on Humulus. It is a notable parasite of lucerne. In many regions, including the Nepal Eastern Himalayas, this species are used as traditional medicine to treat hepatic diseases.
Cuscuta epithymum is a parasitic plant assigned to the family Cuscutaceae or Convolvulaceae, depending on the taxonomy. It is red-pigmented, not being photosynthetically active. It has a filiform habit, like a group of yarns. Its leaves are very small, like flakes. Its flowers, disposed in little glomerules, have a white corolla, with the androecium welded to the corolla.
Cuscuta approximata is a species of dodder known by the common name alfalfa dodder. It is native to Eurasia and Africa, but it is also found in North America, where it is an introduced species and uncommon noxious weed. It is a parasitic vine which climbs other plants and takes nutrition directly from them via a haustorium. The dodder resembles a pile of light yellow to orange-red straw wrapped tightly around its host plant. It is mostly stem; the leaves are reduced to scales on the stem's surface, since they are not needed for photosynthesis while the dodder is obtaining nutrients from its host. It bears clusters of tiny yellowish bell-shaped flowers which are only about 3 millimeters wide. The dodder reproduces by seed, with each plant capable of producing over 10,000 seeds at once. This plant is a weed of alfalfa, clover, and tomatoes, as well as other crop plants and native flora. This species is sometimes treated as a subspecies of Cuscuta epithymum.
Mikania micrantha is a tropical plant in the family Asteraceae; known as bitter vine, climbing hemp vine, or American rope. It is also sometimes called mile-a-minute vine.
Cuscuta salina is a species of dodder known by the English name salt marsh dodder and is a native plant of western North America. The habitat includes coastal tidal wetlands in California, as well as saline habitats away from the coast, such as vernal pools and salt flats. Salt Marsh Dodder is a parasitic plant, wrapping orange-colored stems around natural wetland vegetation and absorbing nutrients of host plants via their specialized structures called haustoria.
Striga hermonthica, commonly known as purple witchweed or giant witchweed, is a hemiparasitic plant that belongs to the family Orobanchaceae. It is devastating to major crops such as sorghum and rice. In sub-Saharan Africa, apart from sorghum and rice, it also infests maize, pearl millet, and sugar cane.
Cassytha pubescens is a native Australian hemiparasitic vine species, in the Laurel family. Common names for the species include devils twine, dodder-laurel, spilled devil's twine, snotty gobble or downy dodder-laurel. It is a widespread and common species in south eastern Australia. The species was first formally described in 1810 by the Scottish botanist Robert Brown in Prodromus Flora Novae Hollandiae et Insulae Van Diemen. Leaves are reduced to scales and photosynthesis is achieved through chlorophyll contained in the plants stems. Stems are between 0.5mm and 1.5mm in diameter and the haustoria are between 2 and 3 mm long.
Phoradendron tomentosum, the leafy mistletoe, hairy mistletoe or Christmas mistletoe, is a plant parasite. It is characterized by its larger leaves and smaller berries than dwarf mistletoe. Leafy mistletoe seldom kill but they do rob their hosts of moisture and some minerals, causing stress during drought and reducing crop productions on fruit and nut trees. Leafy mistletoe has the ability to photosynthesize on its own but it relies on other plants in order to obtain its nutrients. It attaches itself to a tree and then grows haustoria, in order to get the food and water it needs.
Cuscuta pacifica is a species of dodder. Its common name is goldenthread.
Cuscuta denticulata, commonly known as desert dodder or small-toothed dodder, is a thin, yellow to orange, parasitic annual vine in the morning glory family (Convulvulaceae), native to the deserts of the south-western United States and northern Mexico.
Cuscuta compacta, the compact dodder, is a parasitic plant that specializes on woody plants. This species is distributed across the Eastern and Midwestern USA, Eastern Canada, and Mexico.
Cuscuta gronovii is a yellow vine that grows as a parasite off other plants. It is a dicot.
Cuscuta glomerata is a parasitic plant in the morning glory family, Convolvuaceae. It is commonly known by the name rope dodder.