Orobanche minor | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Lamiales |
Family: | Orobanchaceae |
Genus: | Orobanche |
Species: | O. minor |
Binomial name | |
Orobanche minor | |
Orobanche minor, the hellroot, [1] common broomrape, lesser broomrape, small broomrape or clover broomrape, is a holoparasitic flowering plant belonging to the family Orobanchaceae. It is one of about 150 non-photosynthetic plants in the genus Orobanche that parasitize autotrophic plants.
Orobanche minor grows to 0.5 m (1 ft 8 in) and is a perennial.[ citation needed ] The flowers are hermaphrodite.
Common broomrape grows in a wide variety of soils, namely moist, light (sandy), medium (loamy) and heavy (clay) soils that are acid, neutral or basic. It can grow in semi-shade or in full sunlight. [2]
The species appears in a wide range of colours from red-brown, yellow-brown to purple. Yellow specimens are also not uncommon and it is this extreme variability that makes identification on the basis of size or colour uncertain. [3] It is parasitic on various members of the pea (Fabaceae) and daisy (Asteraceae) families. Although widespread, its appearance is sporadic; despite this, it can occur in vast colonies from time to time. The main flowering season in the northern hemisphere is from May until the end of August and from August to January in the southern hemisphere. [4] The species has efficient seed dispersal and is largely inbreeding so that populations preferentially parasitizing a particular species which has its own clear ecological preferences may become effectively isolated and eventually may produce distinct taxa. [5]
The plants are attached to their host by means of haustoria, which transfer nutrients from the host to the parasite. Only the hemiparasitic species possess an additional extensive root system. The root system is reduced as its function is mainly anchorage of the plant.
Common broomrape is one of the most widespread species, and is native to Southern Europe, [6] but has been widely introduced elsewhere, for example in the United States. [7] In New Zealand it is the only species of the genus present where it is regarded as an agricultural pest. [4] In the United Kingdom it is widely recorded in southern England, less common in Wales, rarely recorded in lowland Scotland and absent from the Highlands and outer islands. [8]
Phylogenetic analyses have placed this species in the taxonomically difficult Minores species complex. [9] [10] Four infraspecific taxa of Common broomrape are currently recognised in the United Kingdom: O. minor var. minor, O. minor var. flava, O. minor var. compositarum and O. minor subsp. maritima. [11] [12] Chromosome No.: 2n = 38. The genetic structure of populations of O. minor are under investigation using molecular markers and DNA sequencing to help resolve the taxonomic and nomenclatural problems that have historically been linked with this species. [13]
The common broomrape is highly generalist in its host range, and can infect hundreds of species in families from the Ranunculaceae to the Poaceae (=Gramineae) but with a clear preference for the Fabaceae (=Leguminosae) and Asteraceae (=Compositae). [11] However races occurring on different species of host are genetically divergent [14] and physiologically adapted to their local hosts, and may therefore be in a state of incipient speciation. [15] Urgent conservation efforts are required as the survival of some intraspecific taxa is very uncertain. [13]
Rhinanthus minor, known as yellow rattle, is a herbaceous wildflower in the genus Rhinanthus in the family Orobanchaceae. It has circumpolar distribution in Europe, Russia, western Asia, and northern North America. An annual plant, yellow rattle grows up to 10–50 centimetres (3.9–19.7 in) tall, with upright stems and opposite, simple leaves. The fruit is a dry capsule, with loose, rattling seeds.
Paulowniaceae are a family of flowering plants within the Lamiales. They are a monophyletic and monogeneric family of trees with currently 7 confirmed species. They were formerly placed within Scrophulariaceae sensu lato, or as a segregate of the Bignoniaceae.
Orobanche, commonly known as broomrape, is a genus of almost 200 species of small parasitic herbaceous plants, mostly native to the temperate Northern Hemisphere. It is the type genus of the broomrape family Orobanchaceae.
Orobanchaceae, the broomrapes, is a family of mostly parasitic plants of the order Lamiales, with about 90 genera and more than 2000 species. Many of these genera were formerly included in the family Scrophulariaceae sensu lato. With its new circumscription, Orobanchaceae forms a distinct, monophyletic family. From a phylogenetic perspective, it is defined as the largest crown clade containing Orobanche major and relatives, but neither Paulownia tomentosa nor Phryma leptostachya nor Mazus japonicus.
Rehmannia is a genus of seven species of flowering plants in the order Lamiales and family Orobanchaceae, endemic to China. It has been placed as the only member of the monotypic tribe Rehmannieae, but molecular phylogenetic studies suggest that it forms a clade with Triaenophora. Contrary to the immense majority of the taxa of Orobanchaceae, Rehmannia is not parasitic.
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.
Lindenbergia is a genus of herbaceous plants in the order Lamiales and in the broomrape family Orobanchaceae. It is one of the few genera of the family which are not parasitic. It contains about 15 species found from northeast Africa across Asia to the Philippines, and is most abundant in India.
Cistanche is a worldwide genus of holoparasitic desert plants in the family Orobanchaceae. They lack chlorophyll and obtain nutrients and water from the host plants whose roots they parasitize. They are often known as desert hyacinths.
Orobanche pinorum is a species of broomrape known by the common name conifer broomrape. It is native to the forests of western North America, where it is a parasite growing attached to the roots of other plants, usually Holodiscus species. This plant has an erect stem with a wide, thickened base and slender top growing 10–30 centimetres (3.9–11.8 in) tall. As a parasite taking its nutrients from a host plant, it lacks leaves and chlorophyll and is brownish or yellowish in color. The inflorescence is a dense, spreading array of purple-tinged yellowish flowers 1–2 centimetres (0.39–0.79 in) long.
Orobanche rapum-genistae, the greater broomrape, is a plant species in the genus Orobanche. It is a parasitic plant, native to Europe, growing on the roots of plants in the bean family, usually common broom or European gorse.
Boschniakia rossica, commonly known as the northern groundcone, is a holoparasitic plant that lives in the northern latitudes of the northern hemisphere. In the Pacific Northwest Temperate Rainforest, it does not grow south of Prince of Wales Island, beyond that boundary is the Vancouver groundcone habitat. It does not contain chlorophyll, so it must be parasitic to obtain nutrients. It specializes on Alnus species, but can parasitize off of other trees and shrubs such as on Betula (birch), Salix (willow), Vaccinium (blueberry), Picea (spruce), and Chamaedaphne. This organism is likely to be found at mid elevations alongside rivers and streams, where moisture is abundant. This species propagates itself through water flow. In some places bears are known to have eaten the starchy roots, or tubers, of this plant.
Aeginetia indica, commonly known as Indian broomrape or forest ghost flower, is a holoparasitic herb or root parasite of the plant family Orobanchaceae. It grows in moist deciduous and semi-evergreen forests of tropical and subtropical Asia and New Guinea. It parasitises plants of the families Cannaceae, Commelinaceae, Cyperaceae, Juncaceae, Poaceae, and Zingiberaceae.
Orobanche ludoviciana, the Louisiana broomrape or prairie broom-rape, is a species of plant in the family Orobanchaceae. It was first described and named by Thomas Nuttall in 1818.
Orobanche hederae, the ivy broomrape, is, like other members of the genus Orobanche, a parasitic plant without chlorophyll, and thus totally dependent on its host, which is ivy. It grows to 60 cm (2 ft), with stems in shades of brown and purple, sometimes yellow. The flowers are 10–22 mm (0.4–0.9 in) long, cream in colour with reddish-purple veins.
Cospeciation is a form of coevolution in which the speciation of one species dictates speciation of another species and is most commonly studied in host-parasite relationships. In the case of a host-parasite relationship, if two hosts of the same species get within close proximity of each other, parasites of the same species from each host are able to move between individuals and mate with the parasites on the other host. However, if a speciation event occurs in the host species, the parasites will no longer be able to "cross over" because the two new host species no longer mate and, if the speciation event is due to a geographic separation, it is very unlikely the two hosts will interact at all with each other. The lack of proximity between the hosts ultimately prevents the populations of parasites from interacting and mating. This can ultimately lead to speciation within the parasite.
Orobanche reticulata is a species of broomrape known by the common name thistle broomrape. It is a parasitic plant whose host is normally the creeping thistle. It is native to the lowlands of Western Europe and Central Asia, but in the United Kingdom it is a rare and protected plant, growing only in Yorkshire, on grassland sites such as Quarry Moor.
Triaenophora is a genus of flowering plants native to Temperate Asia. Its family placement is not fully settled, as of March 2022: it may be placed in Orobanchaceae or Plantaginaceae.
Orobanche alba, also known by its common names thyme broomrape and red broomrape, is a holoparasitic plant of the broomrape family. It parasitises plants from the mint family.