Cruciferae
New name :Brassicaceae
Classification : Dicot
Subclass : Polypetalae
Series : Thalamiflorae
Order : Parietales
Family : Cruciferae
Identifying characters :
Plant – pungent smelling herbs
Leaves- exstipulate
Inflorescence - racemose
Flowers – ebracteate, tetramerous, hypogynous , actinomorphic
Calyx – imbricate , 2+2 (two outer and two inner)
Corolla – polypetalous , cruciform , imbricate , or valvate
Androecium – stamens-6 , 2+4 (two outer shorter and four inner longer- tetradynamous)
Gynoecium – monocarpellary (become bicarpellary due to development of false septum – replum)
Fruit - siliqua or silicula
Floral formula – Ebr. Φ K4 C4 A2+4 G(2)
Distribution – The family includes about 350 genera and 3200 species . The plants are world wide in distribution but they abundantly grow in temperate and cold parts of the Northern hemisphere. Many species are cultivated for vegetables and oil yielding seeds.
Vegetative characters :
Root : tap root system. In some species tap root is modified into various forms due to storage of food , branched , fusiform (radish) , napiform (turnip),etc.
Stem : erect , herbaceous, rarely wood , solid or fistular, cylindrical, glabrous, branched or unbranched, hairy . the main stem becomes very much condensed in some species like Raphanus sativus (Radish)
Leaf : radical (radish) , cauline and ramal , simple , alternate, radical leaves, generally occur on the reduced stem and form rosettes. Eg. Radish, rarely compound ( sim sag ), petiolate , sometime sessile , lyrate , exstipulate, margin smooth, wavy or dentate, hairy , unicostate and reticulate venation , acute or obtuse, entire or variable , glabrous or hairy.
Reproductive characters :
Inflorescence : racemose type , generally raceme or corymb, sometimes corymbose- raceme as in candytuft.
Flower : ebracteate , pedicellate, bisexual, complete, actinomorphic, rarely zygomorphic ( Iberis amara) i.e candytuft , tetramerous or bimerous, hypogynous, perigynous In Lepidium , cyclic.
Calyx : four sepals, polysepalous, imricate aestivation. The sepals may be caduceus, green or petalloid, inferior. Number of sepals = 4 (2+2) two outer and two inner.
Corolla : four petals, polypetalous, cruciform i.e four petals arranged crosswise , each petal consists of broad limb and narrow stalked claw , alternating with sepals, two anterior petals larger in Iberis amara , petals are reduced in Coronopus or absent in Lepidium , inferior, valvate aestivation.
Androecium : sis stamens (+4), two outer shorter and four inner larger- tetradynamous , polyandrous, anthers – basifixed or dorsifixed , dithecous (bithecous), nectar glands present at the base of stamens , introse.
Gynoecium : bicarpellary, syncarpous , carpels placed transversely, ovary superior, unilocular in the early stage but later it becomes bilocular due to the development of false septum called replum, ovules many in each locule, parietal placentation, style- short , stigma- capitate, simple or bilobed.
Fruit : siliqua or silicula – ( dry, dehiscent, cylindrical, fruit, develop from bicarpellary ovary and dehises In two valve.
Floral Formula and Diagram :
New name :Brassicaceae
Classification : Dicot
Subclass : Polypetalae
Series : Thalamiflorae
Order : Parietales
Family : Cruciferae
Identifying characters :
Plant – pungent smelling herbs
Leaves- exstipulate
Inflorescence - racemose
Flowers – ebracteate, tetramerous, hypogynous , actinomorphic
Calyx – imbricate , 2+2 (two outer and two inner)
Corolla – polypetalous , cruciform , imbricate , or valvate
Androecium – stamens-6 , 2+4 (two outer shorter and four inner longer- tetradynamous)
Gynoecium – monocarpellary (become bicarpellary due to development of false septum – replum)
Fruit - siliqua or silicula
Floral formula – Ebr. Φ K4 C4 A2+4 G(2)
Distribution – The family includes about 350 genera and 3200 species . The plants are world wide in distribution but they abundantly grow in temperate and cold parts of the Northern hemisphere. Many species are cultivated for vegetables and oil yielding seeds.
Vegetative characters :
Root : tap root system. In some species tap root is modified into various forms due to storage of food , branched , fusiform (radish) , napiform (turnip),etc.
Stem : erect , herbaceous, rarely wood , solid or fistular, cylindrical, glabrous, branched or unbranched, hairy . the main stem becomes very much condensed in some species like Raphanus sativus (Radish)
Leaf : radical (radish) , cauline and ramal , simple , alternate, radical leaves, generally occur on the reduced stem and form rosettes. Eg. Radish, rarely compound ( sim sag ), petiolate , sometime sessile , lyrate , exstipulate, margin smooth, wavy or dentate, hairy , unicostate and reticulate venation , acute or obtuse, entire or variable , glabrous or hairy.
Reproductive characters :
Inflorescence : racemose type , generally raceme or corymb, sometimes corymbose- raceme as in candytuft.
Flower : ebracteate , pedicellate, bisexual, complete, actinomorphic, rarely zygomorphic ( Iberis amara) i.e candytuft , tetramerous or bimerous, hypogynous, perigynous In Lepidium , cyclic.
Calyx : four sepals, polysepalous, imricate aestivation. The sepals may be caduceus, green or petalloid, inferior. Number of sepals = 4 (2+2) two outer and two inner.
Corolla : four petals, polypetalous, cruciform i.e four petals arranged crosswise , each petal consists of broad limb and narrow stalked claw , alternating with sepals, two anterior petals larger in Iberis amara , petals are reduced in Coronopus or absent in Lepidium , inferior, valvate aestivation.
Androecium : sis stamens (+4), two outer shorter and four inner larger- tetradynamous , polyandrous, anthers – basifixed or dorsifixed , dithecous (bithecous), nectar glands present at the base of stamens , introse.
Gynoecium : bicarpellary, syncarpous , carpels placed transversely, ovary superior, unilocular in the early stage but later it becomes bilocular due to the development of false septum called replum, ovules many in each locule, parietal placentation, style- short , stigma- capitate, simple or bilobed.
Fruit : siliqua or silicula – ( dry, dehiscent, cylindrical, fruit, develop from bicarpellary ovary and dehises In two valve.
Floral Formula and Diagram :
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