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Orobanchaceae

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23-422: 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 (e.g., Pedicularis , Rhinanthus , Striga ) were formerly included in the family Scrophulariaceae sensu lato . With its new circumscription, Orobanchaceae forms a distinct, monophyletic family. From a phylogenetic perspective, it

46-612: A cosmopolitan distribution , found mainly in temperate Eurasia , North America , South America , parts of Australia , New Zealand , and tropical Africa . The only exception to its distribution is Antarctica, though some genera may be found in subarctic regions. This family has tremendous economic importance because of the damage to crops caused by some species in the genera Orobanche and Striga . They often parasitize cereal crops like sugarcane , maize , millet , sorghum , and other major agricultural crops like cowpea , sunflower , hemp , tomatoes , and legumes . Because of

69-513: A host, the broomrape robs its host of water and nutrients. Some species are only able to parasitise a single plant species, and they are often named after the plant they parasitise, such as ivy broomrape ( O. hederae ) being restricted to parasitising ivy . Others can infect several genera, such as the lesser broomrape O. minor , which lives on clover and other related Fabaceae . Branched broomrape Orobanche ramosa , native to central and southwestern Europe but widely naturalised elsewhere,

92-554: A lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called

115-780: A study comparing the rates of molecular evolution of parasitic versus non parasitic taxa for 12 pairs of angiosperm families — including Apodanthaceae , Cytinaceae , Rafflesiaceae , Cynomoriaceae , Krameriaceae , Mitrastemonaceae , Boraginaceae , Orobanchaceae, Convolvulaceae , Lauraceae , Hydnoraceae , and Santalaceae / Olacaceae —, parasitic taxa evolve on average faster than their close relatives for mitochondrial, plastid, and nuclear genome sequences. Whereas Orobanchaceae fit to this trend for plastid DNA, they appear to evolve slower than their non parasitic counterpart in comparisons involving nuclear and mitochondrial DNA. 99 genera are accepted. Orobanchaceae genera listed according to their life history trait. The family Orobanchaceae has

138-526: 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. It is a weed on broadleaf crop plants in Australia, where some states enforce mandatory destruction and reporting, as well as prohibition of sale. Broomrapes are generally small, only 10–60 centimetres (4–24 inches) tall depending on species. They are best recognized by

161-499: Is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to

184-507: Is considered a major threat to crops in some areas. Plants that it targets are tomato , eggplant , potato , cabbage , coleus , bell pepper , sunflower , celery , and beans . In heavily infested areas, branched broomrape can cause total crop failure. The bean broomrape Orobanche crenata , which targets the fava bean , has stems that are gathered and eaten in the Italian region of Apulia . The generic name Orobanche comes from

207-548: Is defined as the largest crown clade containing Orobanche major and relatives, but neither Paulownia tomentosa nor Phryma leptostachya nor Mazus japonicus . The Orobanchaceae are annual herbs or perennial herbs or shrubs , and most (all except Lindenbergia , Rehmannia and Triaenophora ) are parasitic on the roots of other plants—either holoparasitic or hemiparasitic (fully or partly parasitic). The holoparasitic species lack chlorophyll and therefore cannot perform photosynthesis . Orobanchaceae

230-485: Is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family

253-455: Is the largest of the 20–28 dicot families that express parasitism. Apart from a few non-parasitic taxa, the family displays all types of plant parasitism: facultative parasite , obligate parasite , hemiparasites, and holoparasites. Parasitic 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 referred to as

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276-479: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Orobanche Orobanche , commonly known as broomrape ,

299-405: The apex of the slender stem. The tubular calyx is formed by 2–5 united sepals. There are five united, bilabiate petals forming the corolla and they may be yellowish, brownish, purplish, or white. The upper lip is two-lobed, the lower lip is three-lobed. There are two long and two short stamens on slender filaments, inserted below the middle, or at the base of the corolla tube, alternating with

322-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and

345-683: The lateral or side haustoria. In most holoparasitic species there is a swollen mass of short, bulky roots or one big swollen haustorial organ, which may be simple or composite, commonly called the terminal or primary haustorium. Plants are reduced to short vegetative stems, their alternate leaves are reduced to fleshy, tooth-like scales, and have multicellular hairs interspersed with glandular hairs. The hemiparasitic species (transferred from Scrophulariaceae) with green leaves are capable of photosynthesis, and may be either facultative or obligate parasites. The hermaphroditic flowers are bilaterally symmetrical and grow either in racemes or spikes or singly at

368-858: The latter is now morphologically and molecularly considered monophyletic, though many of its genera were once considered a part of the family Scrophulariaceae. Lindenbergia , once treated as a member of the Scrophulariaceae, is one of the only autotrophic genera within Orobanchaceae. It is believed to be the sister group to the hemiparasitic genera within its family. The parasitism and its different modes have been suggested to have an impact on genome evolution, with increased DNA substitution rates in parasitic organisms compared to non-parasitic taxa. For example, holoparasite taxa of Orobanchaceae exhibit faster molecular evolutionary rates than confamilial hemiparasites in three plastid genes. In

391-564: The lobes of the tube. A fifth stamen is either sterile or lacking completely. The anthers dehisce via longitudinal slits. The pistil is one-celled. The ovary is superior. The flowers are pollinated by insects or birds (e.g., hummingbirds , as in Castilleja ). The fruit is a dehiscent , non-fleshy, 1-locular capsule with many very minute endospermic seeds . Fruits of Orobanchaceae are small and abundant and can produce between 10,000–1,000,000 seeds per plant. These are dispersed by

414-411: The plants is visible above the surface of the soil. As they have no chlorophyll, the broomrapes are totally dependent on other plants for nutrients. Broomrape seeds remain dormant in the soil, often for many years, until stimulated to germinate by certain compounds produced by living plant roots. Broomrape seedlings put out a root-like growth, which attaches to the roots of nearby hosts. Once attached to

437-575: The seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted

460-600: The ubiquitous nature of these particular parasites in developing countries, it is estimated to affect the livelihood of over 100 million people, killing 20 to 100 percent of crops depending on infestation. Some genera, especially Cistanche and Conopholis , are threatened by human activity, including habitat destruction and over-harvesting of both the plants and their hosts. Research for this plant family can often be difficult due to its permit requirements for collection, travel, and research. Family (biology) Family ( Latin : familia , pl. : familiae )

483-549: The use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,

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506-433: The wind over long distances, which increases their chances of finding a new host. Development of the haustoria was a significant evolutionary event that allowed for the advancement of parasitic plants . The holoparasitic clade, Orobanche , delineates the first transition from hemiparasitism to holoparasitism within Orobanchaceae. Despite the similar morphological traits found in both Scrophulariaceae and Orobanchaceae,

529-487: The yellow- to straw-coloured stems completely lacking chlorophyll , bearing yellow, white, or blue snapdragon -like flowers. The flower shoots are scaly, with a dense terminal spike of 10-20 flowers in most species, although single in one-flowered broomrape ( Orobanche uniflora ). The leaves are merely triangular scales. The seeds are minute, tan or brown, blackening with age. These plants generally flower from late winter to late spring. When they are not flowering, no part of

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