Misplaced Pages

Lepidium

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
#939060

37-463: 265, see text Lepidium is a genus of plants in the mustard/cabbage family, Brassicaceae . The genus is widely distributed in the Americas, Africa, Asia, Europe, and Australia. It includes familiar species such as garden cress , maca , and dittander . General common names include peppercress , peppergrass , pepperweed , and pepperwort . Some species form tumbleweeds . The genus name Lepidium

74-734: A Mathiola species, to seventeen (n=17). About 35% of the species in which chromosomes have been counted have eight sets (n=8). Due to polyploidy , some species may have up to 256 individual chromosomes, with some very high counts in the North American species of Cardamine , such as C. diphylla . Hybridisation is not unusual in Brassicaceae, especially in Arabis , Rorippa , Cardamine and Boechera . Hybridisation between species originating in Africa and California, and subsequent polyploidisation

111-717: A blade and a claw or not, and consistently lack basal appendages. The blade is entire or has an indent at the tip, and may sometimes be much smaller than the claws. The mostly six stamens are set in two whorls: usually the two lateral, outer ones are shorter than the four inner stamens, but very rarely the stamens can all have the same length, and very rarely species have different numbers of stamens such as sixteen to twenty four in Megacarpaea , four in Cardamine hirsuta , and two in Coronopus . The filaments are slender and not fused, while

148-466: A cross shape. The fruit is an erect, slender, four-sided capsule 4–5.5 cm (1.6–2.2 in) long, called a silique , green maturing to pale grey brown, containing two rows of small shiny black seeds which are released when a silique splits open. A single plant can produce hundreds of seeds, which often scatter several meters from the parent plant. Depending upon conditions, garlic mustard flowers either self-fertilize or are cross-pollinated by

185-661: A cut-flower Matthiola (stock) and the model organism Arabidopsis thaliana (thale cress). Pieris rapae and other butterflies of the family Pieridae are some of the best-known pests of Brassicaceae species planted as commercial crops. Trichoplusia ni ( cabbage looper ) moth is also becoming increasingly problematic for crucifers due to its resistance to commonly used pest control methods. Some rarer Pieris butterflies, such as P. virginiensis , depend upon native mustards for their survival in their native habitats. Some non-native mustards such as Alliaria petiolata (garlic mustard), an extremely invasive species in

222-830: A leafstalk. The leaf blade is usually simple, entire or dissected , rarely trifoliolate or pinnately compound . A leaf rosette at the base may be present or absent. The leaves along the stem are almost always alternately arranged , rarely apparently opposite. The stomata are of the anisocytic type. The genome size of Brassicaceae compared to that of other Angiosperm families is very small to small (less than 3.425 million base pairs per cell), varying from 150 Mbp in Arabidopsis thaliana and Sphaerocardamum spp., to 2375 Mbp Bunias orientalis . The number of homologous chromosome sets varies from four (n=4) in some Physaria and Stenopetalum species, five (n=5) in other Physaria and Stenopetalum species, Arabidopsis thaliana and

259-409: A notch at the tip. The seed does not contain endosperm . Brassicaceae have a bisymmetrical corolla (left is mirrored by right, stem-side by out-side, but each quarter is not symmetrical), a septum dividing the fruit, lack stipules and have simple (although sometimes deeply incised) leaves. The sister family Cleomaceae has bilateral symmetrical corollas (left is mirrored by right, but stem-side

296-638: A rather unpleasant aroma which attracts midges and hoverflies , although the flowers usually pollinate themselves. In June the pale green caterpillar of the orange tip butterfly ( Anthocharis cardamines ) can be found feeding on the long green seed-pods from which it can hardly be distinguished. Garlic mustard is one of the oldest spices used in Europe. Phytoliths in pottery of the Ertebølle and Funnelneck-Beaker culture in north-eastern Germany and Denmark, dating to 4100–3750 BCE, indicate its use in that era. In

333-901: A reliable phylogeny . Although a substantial effort was made through molecular phylogenetic studies , the relationships within the Brassicaceae have not always been well resolved yet. It has long been clear that the Aethionema are sister of the remainder of the family. One analysis from 2014 represented the relation between 39 tribes with the following tree. Aethionemae Megacarpaeae Heliophileae Coluteocarpeae Conringieae Buniadeae Kernereae Schizopetaleae Thlaspideae Isatideae Sisymbrieae Brassiceae Thelypodieae Eutremeae Calepineae Biscutelleae Arabideae Cochlearieae Anchonieae Hesperideae Anastaticeae Dontostemoneae Chorisporeae Euclidieae Iberideae Erysimeae Lepidieae Smelowskieae Yinshanieae Alliaria petiolata Alliaria petiolata , or garlic mustard ,

370-616: A thin wall (or septum). The family contains 372 genera and 4,060 accepted species . The largest genera are Draba (440 species), Erysimum (261 species), Lepidium (234 species), Cardamine (233 species), and Alyssum (207 species). The family contains the cruciferous vegetables , including species such as Brassica oleracea (cultivated as cabbage , kale , cauliflower , broccoli and collards ), Brassica rapa ( turnip , Chinese cabbage , etc.), Brassica napus ( rapeseed , etc.), Raphanus sativus (common radish ), Armoracia rusticana ( horseradish ), but also

407-413: A thin wall grows that divides the cavity, both placentas and separates the two valves (a so-called false septum). Rarely, there is only one cavity without a septum. The 2–600 ovules are usually along the side margin of the carpels, or rarely at the top. Fruits are capsules that open with two valves, usually towards the top. These are called silique if at least three times longer than wide, or silicle if

SECTION 10

#1732851827940

444-401: A variety of insects. Sixty-nine insect herbivores and seven fungi are associated with garlic mustard in Europe. The most important groups of natural enemies associated with garlic mustard were weevils (particularly the genus Ceutorhynchus ), leaf beetles , butterflies , and moths , including the larvae of some moth species such as the garden carpet moth. The small white flowers have

481-755: Is a Greek word meaning 'small scale', which is thought to be derived from a folk medicine usage of the plant to treat leprosy , which cause small scales on the skin. Another meaning is related to the small scale-like fruit. Plants of the World Online accepts 265 species in the genus. 10 species are found in California . Species include: This Brassicales article is a stub . You can help Misplaced Pages by expanding it . Brassicaceae See list of Brassicaceae genera Brassicaceae ( / ˌ b r æ s ɪ ˈ k eɪ s iː ˌ iː , - s i ˌ aɪ / ) or (the older) Cruciferae ( / k r uː ˈ s ɪ f ər i / )

518-499: Is a biennial flowering plant in the mustard family ( Brassicaceae ). It is native to Europe, western and central Asia, north-western Africa, Morocco , Iberia and the British Isles , north to northern Scandinavia , and east to northern Pakistan and Xinjiang in western China. In the first year of growth, plants form clumps of round, slightly wrinkled leaves, that when crushed smell like garlic. The plants flower in spring of

555-559: Is a medium-sized and economically important family of flowering plants commonly known as the mustards , the crucifers , or the cabbage family . Most are herbaceous plants , while some are shrubs . The leaves are simple (although are sometimes deeply incised), lack stipules , and appear alternately on stems or in rosettes . The inflorescences are terminal and lack bracts . The flowers have four free sepals , four free alternating petals , two shorter free stamens and four longer free stamens. The fruit has seeds in rows, divided by

592-564: Is chopped up the cyanide gas is eliminated. Garlic mustard was introduced to North America by European settlers in the 1800s for culinary and medicinal purposes. The species was recorded as being in Long Island in 1868. It has since spread all over North America, apart from the far south of the US and some prairie states and Canadian provinces. It is toxic or unpalatable to many native herbivores, as well as to some native Lepidoptera . The plant

629-571: Is classified as an invasive species in North America. Since being brought to the United States by settlers, it has naturalized and expanded its range to include most of the Northeast and Midwest , as well as south-eastern Canada. It is one of the few invasive herbaceous species able to dominate the understory of North American forests and has thus reduced the biodiversity of many areas. Of

666-602: Is different from out-side), stipules and mostly palmately divided leaves, and mostly no septum. Capparaceae generally have a gynophore , sometimes an androgynophore , and a variable number of stamens. Almost all Brassicaceae have C3 carbon fixation . The only exceptions are a few Moricandia species, which have a hybrid system between C3 and C4 carbon fixation , C4 fixation being more efficient in drought, high temperature and low nitrate availability. Brassicaceae contain different cocktails of dozens of glucosinolates . They also contain enzymes called myrosinases , that convert

703-531: Is surmised for Lepidium species native to Australia and New Zealand. Flowers may be arranged in racemes , panicles , or corymbs , with pedicels sometimes in the axil of a bract, and few species have flowers that sit individually on flower stems that spring from the axils of rosette leaves. The orientation of the pedicels when fruits are ripe varies dependent on the species. The flowers are bisexual , star symmetrical (zygomorphic in Iberis and Teesdalia ) and

740-400: The garlic -like odour of the crushed foliage. All parts of the plant, including the roots, have this smell. It is an herbaceous biennial plant growing from a deeply growing, thin, whitish taproot scented like horseradish . In their first years, plants are rosettes of green leaves close to the ground; these rosettes remain green through the winter and develop into mature flowering plants

777-466: The ovary positioned above the other floral parts . Each flower has four free or seldom merged sepals , the lateral two sometimes with a shallow spur, which are mostly shed after flowering, rarely persistent, may be reflexed, spreading, ascending, or erect, together forming a tube-, bell- or urn-shaped calyx. Each flower has four petals , set alternating with the sepals, although in some species these are rudimentary or absent. They may be differentiated into

SECTION 20

#1732851827940

814-517: The 17th-century Britain, it was recommended as a flavouring for salt fish. It can also be made into a sauce for eating with roast lamb or salad. Early European settlers brought the herb to the New World to use as a garlic-type flavouring. Its traditional medicinal purposes include use as a diuretic . The herb was also planted as a form of erosion control. Today, the chopped leaves are used for flavouring in salads and sauces such as pesto, and sometimes

851-655: The Brassicaceae or recognizing them in the segregate family Cleomaceae . The APG III system has recently adopted this last solution, but this may change as a consensus arises on this point. Current insights in the relationships of the Brassicaceae, based on a 2012 DNA-analysis, are summarized in the following tree. family Resedaceae family Gyrostemonaceae family Pentadiplandraceae family Tovariaceae family Capparaceae family Cleomaceae family Brassicaceae family Emblingiaceae Early classifications depended on morphological comparison only, but because of extensive convergent evolution , these do not provide

888-636: The United States , can be toxic to their larvae . Species belonging to the Brassicaceae are mostly annual , biennial , or perennial herbaceous plants , some are dwarf shrubs or shrubs , and very few vines . Although generally terrestrial, a few species such as water awlwort live submerged in fresh water. They may have a taproot or a sometimes woody caudex that may have few or many branches, some have thin or tuberous rhizomes , or rarely develop runners . Few species have multi-cellular glands. Hairs consist of one cell and occur in many forms: from simple to forked, star-, tree- or T-shaped, rarely taking

925-473: The anthers consist of two pollen producing cavities, and open with longitudinal slits. The pollen grains are tricolpate . The receptacle carries a variable number of nectaries , but these are always present opposite the base of the lateral stamens. There is one superior pistil that consists of two carpels that may either sit directly above the base of the stamens or on a stalk . It initially consists of only one cavity but during its further development

962-571: The class Violales ). Following Bentham and Hooker, John Hutchinson in 1948 and again in 1964 thought the Brassicaceae to stem from near the Papaveraceae . In 1994, a group of scientists including Walter Stephen Judd suggested to include the Capparaceae in the Brassicaceae. Early DNA-analysis showed that the Capparaceae—as defined at that moment—were paraphyletic , and it was suggested to assign

999-456: The flowers and fruit are included as well. The leaves, best when young, taste of both garlic and mustard. The seeds are sometimes used in France to season food. Garlic mustard was once used medicinally as a disinfectant or diuretic, and was sometimes used to treat wounds. Young first-year garlic mustard plants contain up to 100ppm cyanide, a level which is toxic to many vertebrates. Once the plant

1036-541: The following spring. Second-year plants often grow from 30–100 cm (12–39 in) tall, rarely to 130 cm (51 in) tall. The leaves are stalked, triangular through heart shaped, 10–15 cm (3.9–5.9 in) long (of which about half being the petiole ) and 5–9 cm (2.0–3.5 in) broad, with coarsely toothed margins. The flowers are produced in spring and summer in small clusters. Each small flower has four white petals 4–8 mm (0.2–0.3 in) long and 2–3 mm (0.08–0.12 in) broad, arranged in

1073-479: The form of a shield or scale. They are never topped by a gland. The stems may be upright, rise up towards the tip, or lie flat, are mostly herbaceous but sometimes woody. Stems carry leaves or the stems may be leafless (in Caulanthus ), and some species lack stems altogether. The leaves do not have stipules , but there may be a pair of glands at base of leaf stalks and flower stalks . The leaf may be seated or have

1110-570: The genera closest to the Brassicaceae to the Cleomaceae . The Cleomaceae and Brassicaceae diverged approximately 41 million years ago. All three families have consistently been placed in one order (variably called Capparales or Brassicales ). The APG II system merged Cleomaceae and Brassicaceae. Other classifications have continued to recognize the Capparaceae, but with a more restricted circumscription, either including Cleome and its relatives in

1147-461: The glucosinolates into isothiocyanates , thiocyanates and nitriles , which are toxic to many organisms, and so help guard against herbivory. Carl Linnaeus in 1753 regarded the Brassicaceae as a natural group, naming them "Klass" Tetradynamia. Alfred Barton Rendle placed the family in the order Rhoeadales , while George Bentham and Joseph Dalton Hooker in their system published from 1862 to 1883, assigned it to their cohort Parietales (now

Lepidium - Misplaced Pages Continue

1184-456: The importation and release of biological control agents such as those has been repeatedly blocked by the USDA's TAG (Technical Advisory Group). In particular, C. scrobicollis , which is monophagous and has been specifically studied since 2002, continues to be blocked, despite researchers' many petitions for approval. It is currently estimated that adequate control of garlic mustard can be achieved by

1221-518: The introduction of just two weevils, with C. scrobicollis being the most important of the two. None of the roughly 76 species that control this plant in its native range has been approved for introduction as of 2018 and federal agencies continue to use more traditional forms of control, such as chemical herbicides. In North America, the plant offers very little wildlife benefits and is toxic to larvae of certain rarer butterfly species (e.g. Pieris oleracea and Pieris virginiensis ) that lay eggs on

1258-401: The length is less than three times the width. The fruit is very variable in its other traits. There may be one persistent style that connects the ovary to the globular or conical stigma , which is undivided or has two spreading or connivent lobes. The variously shaped seeds are usually yellow or brown in color, and arranged in one or two rows in each cavity. The seed leaves are entire or have

1295-452: The many natural enemies it has in its native range, several have been tested for use as biological control agents . Five weevil species from the genus Ceutorhynchus and one flea beetle were selected as candidates for preliminary testing in the 1990s. Since that time, those studying the candidates have narrowed the list to two or three weevils. Despite the demonstrated effectiveness of C. scrobicollis and C. constrictus in field testing,

1332-572: The next year, producing cross-shaped white flowers in dense clusters. As the flowering stems bloom they elongate into a spike-like shape. When flowering is complete, plants produce upright fruits that release seeds in mid-summer. Plants are often found growing along the margins of hedges , giving rise to the old British folk name of jack-by-the-hedge . Other common names include: garlic mustard , garlic root , hedge garlic , sauce-alone , jack-in-the-bush , penny hedge and poor man's mustard . The genus name Alliaria , "resembling Allium ", refers to

1369-564: The plants, as it is related to native mustards but creates chemicals that they are not adapted to. They have also been known to inhibit growth of ectomycorrhizal fungi . These fungi play many different roles in a forest ecosystem however inhibition by Alliaria petiolata, may impact tree seedlings in a given environment. Though this plant does have antimicrobial properties, it has an overall weak effect on bacterial communities found in soil, which only occurs under temporally specific conditions. Native species, including two stem-mining weevils,

#939060