29-448: See text Cardaminopsis (C.A.Mey.) Hayek Arabidopsis ( rockcress ) is a genus in the family Brassicaceae . They are small flowering plants related to cabbage and mustard . This genus is of great interest since it contains thale cress ( Arabidopsis thaliana ), one of the model organisms used for studying plant biology and the first plant to have its entire genome sequenced. Changes in thale cress are easily observed, making it
58-755: 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
87-733: 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
116-661: 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
145-836: 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
174-409: 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
203-904: 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 List of Brassicaceae genera There are around 350 genera in
232-616: 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
261-413: 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
290-658: A very useful model. Currently, the genus Arabidopsis has nine species and a further eight subspecies recognised. This delimitation is quite recent and is based on morphological and molecular phylogenies by O'Kane and Al-Shehbaz and others. Their findings confirm the species formerly included in Arabidopsis made it polyphyletic . The most recent reclassification moves two species previously placed in Cardaminopsis and Hylandra and three species of Arabis into Arabidopsis , but excludes 50 that have been moved into
319-433: Is a curated online information source for Arabidopsis thaliana genetic and molecular biology research, and The Arabidopsis Book is an online compilation of invited chapters on Arabidopsis thaliana biology. (Note that as of 2013 no further chapters will be published.) In Europe, the model organism resource centre for Arabidopsis thaliana germplasm , bioinformatics and molecular biology resources (including GeneChips )
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#1732765245168348-559: 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
377-503: Is an amphidiploid species originated through hybridization between A. thaliana and diploid A. arenosa . A. neglecta is n=8, as are the various subspecies of A. halleri . As of 2005, A. cebennensis , A. croatica and A. pedemontana have not been investigated cytologically. 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 / )
406-602: 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
435-535: 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
464-878: Is the Nottingham Arabidopsis Stock Centre (NASC) whilst in North America germplasm services are provided by the Arabidopsis Biological Resource Center (ABRC) based at Ohio State University . The ordering system for ABRC was incorporated into the TAIR database in June 2001 whilst NASC has always (since 1991) hosted its own ordering system and genome browser. In 1982, the crew of the Soviet Salyut 7 space station grew some Arabidopsis, thus becoming
493-466: 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
522-655: 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
551-699: 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
580-473: 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
609-583: 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
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#1732765245168638-615: The first plants to flower and produce seeds in space . They had a life span of 40 days. Arabidopsis thaliana seeds were taken to the Moon on the Chang'e 4 lander in 2019, as part of a student experiment. As of May 2022 Arabidopsis thaliana has successfully been grown in samples of lunar soil. Arabidopsis is quite similar to the Boechera genus. The following species previously placed in Arabidopsis are not currently considered part of
667-485: 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
696-582: 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
725-463: The genus. Cytogenetic analysis has shown the haploid chromosome number (n) is variable and varies across species in the genus: A. thaliana is n=5 and the DNA sequencing of this species was completed in 2001. A. lyrata has n=8 but some subspecies or populations are tetraploid. Various subspecies A. arenosa have n=8 but can be either 2n (diploid) or 4n (tetraploid). A. suecica is n=13 (5+8) and
754-461: 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
783-401: 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
812-488: The new genera Beringia , Crucihimalaya , Ianhedgea , Olimarabidopsis , and Pseudoarabidopsis . All of the species in Arabidopsis are indigenous to Europe , while two of the species have broad ranges also extending into North America and Asia . In the last two decades, Arabidopsis thaliana has gained much interest from the scientific community as a model organism for research on numerous aspects of plant biology. The Arabidopsis Information Resource (TAIR)
841-437: The plant family Brassicaceae . The type genus is Brassica (cabbage and mustards). Genera with a large number of species are Alyssum (madworts), Arabis (rockcresses), Cardamine (bittercresses), Draba (whitlow-grasses), Erysimum (wallflowers), Heliophila , Lepidium (pepperworts), Noccaea , Odontarrhena , Physaria (bladderpods), and Rorippa (yellowcresses). The following list includes
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