Alternatively Brassicaceae Burnett (nom. altern.
Including Raphanaceae Horan., Stanle(yace)ae Nutt.
Habit and leaf form. Herbs (mostly), or shrubs (rarely), or lianas (rarely). Plants non-succulent (mainly), or succulent (a few, e.g. Cakile). Annual, biennial, and perennial; with a basal aggregation of leaves, or with neither basal nor terminal aggregations of leaves. Self supporting (usually), or climbing (rarely). When shrubby, often pachycaul. Hydrophytic, helophytic, mesophytic, and xerophytic; when hydrophytic, rooted. Leaves of hydrophytes submerged and emergent. Heterophyllous, or not heterophyllous. Leaves minute to very large; alternate; spiral (usually), or distichous (rarely); fleshy (occasionally), or `herbaceous'; petiolate, or subsessile, or sessile; sheathing to non-sheathing; foetid (sometimes), or without marked odour; simple (usually), or compound (rarely); epulvinate; when compound, pinnate (with articulated leaflets). Lamina when simple, dissected to entire; when simple-dissected, pinnatifid, or runcinate; one-veined (rarely), or pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire, or serrate, or dentate. Leaves without a persistent basal meristem.
Leaf anatomy. Mucilaginous epidermis present (commonly), or absent.
Lamina dorsiventral, or isobilateral, or centric. Minor leaf veins without phloem transfer cells (4 genera).
Stem anatomy. Cork cambium present, or absent; initially in woody species deep-seated. Nodes unilacunar, or tri-lacunar, or multilacunar. Cortical bundles present (rarely), or absent. Medullary bundles present (rarely), or absent. Secondary thickening absent, or developing from a conventional cambial ring, or anomalous (?- given the occasional presence of cortical and/or medullary bundles); usually from a single cambial ring. `Included' phloem present (e.g.Brassica, Cochlearia), or absent. Xylem with fibre tracheids; with vessels. Vessel end-walls simple. Vessels with vestured pits. Wood partially storied, or not storied (?); parenchyma paratracheal (scarce). Sieve-tube plastids P-type, or S-type; when P-type type I (b).
Reproductive type, pollination. Hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in `inflorescences' (usually), or solitary (rarely); usually in racemes. The terminal inflorescence unit racemose. Flowers usually ebracteate; ebracteolate; minute to medium-sized; more or less regular (usually), or somewhat irregular. The floral asymmetry (when noticeable) involving the perianth (the outer petals of pseudanthia sometimes radiate and larger). Flowers 2 merous; cyclic. Floral receptacle nearly always with neither androphore nor gynophore (by contrast with Capparidaceae - the long, slender gynophore of Stanleyeae being exceptional). Free hypanthium absent. Hypogynous disk present (often), or absent; of separate members, or annular.
Perianth with distinct calyx and corolla, or sepaline (the corolla occasionally lacking); 8 (usually), or 4; characteristically 3 whorled (K 2+2, C 4); isomerous. Calyx 4; 2 whorled; polysepalous; regular; decussate. Corolla 4 (diagonal); 1 whorled; polypetalous; imbricate, or contorted; regular (usually); white, or yellow, or orange, or purple, or blue. Petals usually clawed.
Androecium 6 (usually), or 2-4, or 8-16 (rarely). Androecial members branched (usually, in that the inner whorl of 4 is derived from only 2 primordia), or unbranched; free of the perianth; markedly unequal (usually, the outer pair shorter), or all equal; free of one another, or coherent (the inner four sometimes basally connate in pairs); 2 - whorled (usually, 2+4), or 1 - whorled. Androecium exclusively of fertile stamens. Stamens 6 (usually), or 2-4, or 8-16 (rarely); tetradynamous (nearly always), or not didynamous, not tetradynamous (when the outer pair missing). Filaments appendiculate, or not appendiculate. Anthers basifixed; non-versatile; dehiscing via longitudinal slits; introrse; unilocular to bilocular; tetrasporangiate; variously appendaged, or unappendaged. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with one middle layer, or initially with more than one middle layer; of the `monocot' type. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate, or nonaperturate (occasionally); 3(-10) - aperturate; colpate; 3-celled.
Gynoecium 2; syncarpous; eu-syncarpous; superior. Ovary `falsely' 2 locular. Gynoecium transverse. Ovary sessile (usually), or stipitate (rarely, cf. Capparidaceae). Styles 1 (more or less reduced); apical. Stigmas 1-2; commissural; 1 - lobed, or 2 - lobed; more or less capitate; dry type; papillate; Group II type. Placentation parietal (the two placentae each longitudinally divided by a septum, the `replum', separating the locules). Ovules (1-)3-50 per locule (i.e. usually several to `many' per placenta); commonly pendulous, or horizontal; with ventral raphe; non-arillate; anatropous; bitegmic; tenuinucellate, or crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids hooked (sometimes with filiform apparatus). Endosperm formation nuclear. Embryogeny onagrad.
Fruit non-fleshy; usually dehiscent; a silicule, or a siliqua (with variations on this theme). Capsules valvular (the valves falling to reveal the replum). Seeds scantily endospermic, or non-endospermic; small to medium sized. Embryo well differentiated. Cotyledons 2. Embryo chlorophyllous (32/52); bent (folded, the cotyledons against the radicle).
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Mustard-oils present. Cyanogenic, or not cyanogenic. Alkaloids present, or absent (more often). Iridoids absent. Proanthocyanidins absent (except sometimes in the seedcoat). Flavonols present, or absent; when present, kaempferol and quercetin. Ellagic acid absent (9 species, 7 genera). Arbutin absent. Aluminium accumulation not found. C3 (almost exclusively), or C3-C4 intermediate. C3 recorded in Barbarea, Berteroa, Brassica, Cakile, Capsella, Cheiranthus, Crambe, Dipterygium, Farsetia, Matthiola, Raphanus, Sisymbrium, Thlaspi. C3-C4 intermediacy in Moricandia (3 species). Anatomy non-C4 type (Aethionema, Alyssum, Arabis, Brassica, Capsella, Cardamine, Descurainia, Diceratella, Draba, Erysimum, Erucastrum, Farsetia, Fortuynia, Leavenworthia, Lepidium, Lesquerella, Matthiola, Morieria, Oreophyton, Rorippa, Sisymbrium, Thlaspi etc.).
Geography, cytology. Frigid zone to tropical. Cosmopolitan, concentrated in the North temperate and Mediterranean. X = 5-12(+).
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren's Superorder Violiflorae; Capparales. Cronquist's Subclass Dilleniidae; Capparales. Takhtajan's Subclass Dilleniidae; Dillenianae; Capparales. Species 3200. Genera about 350; Aethionema, Alliaria, Alyssum, Arabidopsis, Arabis, Armoracia, Aubretia, Barbarea, Brassica, Cakile, Capsella, Cardamine, Chalcanthus, Clausia, Cochlearia, Coronopus, Crambe, Diplotaxis, Draba, Drabopsis, Erophila, Eruca, Erucaria, Erysimum, Fortuynia, Glastaria, Goldbachia, Harmsiodoxa, Hemicrambe, Hesperis, Hirschfeldia, Hornungia, Iberis, Isatis, Iti, Kernera, Lachnocapsa, Lepidium, Lunaria, Matthiola, Moricandia, Morisia, Muricaria, Nasturtium (= Rorippa), Neslia, Octoceras, Oudneya, Pachycladon, Parlatoria, Parrya, Peltaria, Phlebolobium, Physaria, Pringlea, Pyramidium, Raphanus, Rapistrum, Rollinsia, Rorippa, Savignya, Selenia, Sinapis, Sisymbrium, Sophiopsis, Stanleya, Streptoloma, Taphrospermum, Teesdalia, Thelypodium, Thlaspi, Turritis, Vella, Warea, Werdermannia, Winklera, Xerodraba, Zerdana, Zilla, etc.
For family review, see Vaughan, Macleod and Jones 1976.
Economic uses, etc. Important food crops from Brassica (cabbage, cauliflower, broccoli, kohlrabi, turnips, Brussels sprouts); Raphanus (radish); Rorippa (watercress); condiments from Brassica (mustard), Armoracia (horse-radish); ornamentals from about 50 genera, e.g. Matthiola, Hesperis, Cheiranthus, Lunaria, Iberis, Alyssum, Arabis.
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