Brassicaceae Week: Introduction.: Brassicaceae(Crusiferae) Mustard family
The family contains over 330 genera and about 3,700 species, according to the Royal Botanic Gardens, Kew.
Annual, biennial or perennial herbs (Rarely under shrubs) with watery sap, (pungent juice) containing glucosinolates (mustard oils) and with myoresin cells. Hairs simple branches stellate or peltate.
Vegetative characters :
Leaves : alternate or in basal rosettes,radical or cauline,simple often dissected, rarely pinnately compound sometimes bearing bulbils in axils or leaf surface. Stipules absent.
Inflorescence : Typically racemose, corumbose raceme or flat topped corymb.
Flowers : ebracteate, rarely bracteate.bisexual actinomorphic rarely zygomorphic hypogynous.
Calyx : with 4 sepals free in two whorls.Sepals of lateral pair sometimes saccate at base green or petalloid.
Corolla : 4 petals cruciform, clawed.
Androecium : stamens 6 free tetradinamous(2 short 4 long) dehiscence longitudinal.Nectaries often at base of stamens, pollen grains tricolpate.
Gynoecium : Two united carpels (thus single pistil) syncarpous unilocular.Ovary superior.Gynophore distinct.Style 1 stigmas 2.
Fruit : Siliqua or silicula
Pollination : by insects and dispersal of seeds by wind.
Family contributes to many food plants
Radish (Raphenous sativus)
Cabbage (Brassica oleracea var : capitata)
Cauliflower (Brassica oleracea var : botrytis)
Brassiaca campestris : seeds yield mustard oil used for cooking
Brassica nigra : black variety seeds used as condiment.
Common ornamentals include: stock (Mathiola) candy tuft (Iberis amara) alyssum (Alyssum) wall flower (Erysimum) and street alyssum(Lobularia)
In Maharashtra the family has following genera under it. (BSI Mah Flora)
An important statements in the book Flowers of Himalaya regarding this family.
"Ripe fruits are necessary for the identification of both genera and species.
Many genera are differentiated by small and often obscure botanical characters, particularly of the fruit, about which experts do not always agree;"
Reproducing a KEY from FOH by Polunin and Stainton
Fruit short, a silicula(Less than 3 times as long as broad)
a) Leaves entire, or toothed. 1BRAYA 2 CRAMBE 3 DRABA 4 ISATIS 5 LEPIDIUM 6 PEGAEOPHYTON 7 THLASPI
b) Leaves deeply lobed 8 MEGACARPAEA
Fruit long, a siliqua(More than 3 times as long as broad)
a) Leaves entire or toothed
i) Flowers white violet,purple or pink 9 ARABIDOPSIS 10ARABIS 11 ARCYOSPERMA 12 CHRISTOLEA 13 ERMANIA 14 MATTHIOLA 15 PHAEONYCHIUM 16 PYCHNOPLINTHOPSIS
ii) Flowers yellow ororange 17 ERYSIMUM
b) Leaves deeply lobed, or compound
i) Flowers white violet or pink 18CARDAMINE 19 CHORISPORA 20 LIGNARIELLA 21 PARRYA 22RAPHANUS 23 RORIPPA
ii) Flowers yellow 24 BARBAREA 25 BRASSICA
Species & genera pages of Brassicaceae are now with images.
I request members to pl. go through & point out mistakes, if any.