菊科 ju ke
Herbs, subshrubs, or shrubs, rarely trees, sometimes with lactiferous or resinous canals. Leaves usually alternate, rarely opposite or whorled, entire or dentate, or divided, with stipules or sometimes petioles expanded and stipule-like at base. Florets hermaphroditic or unisexual (imperfect), rarely plants trioecious, regular or zygomorphic; 5-merous, few or many crowded into capitulum or spike, enclosed in an involucre of 1 to many seriate bracts. Capitula solitary or several to many in a raceme, cyme, corymb, panicle, or spike; receptacle flat or convex, areolate or exareolate, hairy or not, paleaceous or not. Calyx usually reduced to palea scales or bristle-like pappus. Corolla usually radiate, tubular, or zygomorphic, bilabiate or ligulate. Capitula discoid or radiate, homogamous. Florets all tubular or ligulate, or heterogamous; outer ones female, ligulate; inner ones bisexual, tubular. Stamens 4 or 5, inserted within corolla-tube; filaments usually free; anthers basifixed, usually connate into a tube, obtuse or acute, hastate or tailed. Style apically bifid; style arms with appendage or not. Ovary hypogynous, 1-loculed, with 1 ovule. Fruit an indehiscent achene. Seed erect, albumen absent, embryo straight, dicotyledons, rarely monocotyledons.
About 1535 genera and 25000–30000 species worldwide, rare in tropical regions; 235 genera and nearly 2500 species throughout China.
Many of species are important economically including garden lettuce, crown daisy, Helianthus tuberosus, etc. which are used as vegetables. The seeds of Helianthus annuus, Guizotia abyssinica, and Xanthium sibiricum can be pressed for oil which is edible or used industrially; Taxaracum kok-saghyz, Parthenium hysterophorus can be used to produce rubber; Carthamus tictorius, Blumea balsamifera can be used to make borneol; Pyrethrum coccineum and Pyrethrum cinerarifolium are used as insecticide; Eupatorum japonicum, Aster tataricus, Inula japonica, Carpesium cernuum, Artemisia capillaris, A. argyi, Atractylis macrocephala, A. lancea, Arctium lappa, Carthamus tinctorius, and Taraxacum mongolicum are important medicinal plants; in addition, Dendranthema morifolium, Callistephus chinensis, Dahlia bipinnata, Coreopsis tictoria, Rudbeckia spp., and many others have colorful flowers and are used ornamentally and cultivated in gardens and parks worldwide.
Based on the structure of the flowers in the capitula, and the plants having milky latex or not, the family can be separated into subfamilies and 13 tribes.
Key to subfamilies and tribes
1a. Capitula all ray florets, ray apically 5-denticulate; style arms slender, linear, without appendage; leaves alternate; plants often containing latex ............................................................................. 12. Lactuceae
1b. Capitula with flowers all homomorphic tubular, or heteromorphic, central flower eligulate, plants not containing latex ............................................................................................................. 1. Carduordeae
2a. Anthers obtuse or slightly acute.
3a. Style arms cylindrical, apically with clavate or flattened obtuse appendage; capitula discoid, florets homomorphic tubular; leaves usually opposite .......................................... 2. Eupatorieae
3b. Style arms not clavate, or rather flattened and obtuse capitula radiate, marginal florets often ligulate or discord without ligulate florets.
4a. Style arms usually plano-convex, with acute or triangular appendage at apex, sometimes obtuse; leaves alternate ............................................................................................... 3. Astereae
4b. Style arms usually truncate, without or with acute or triangular appendage, sometimes subulate.
5a. Pappus usually piliform; capitula radiate or discoid; leaves alternate 8. Senecioneae
5b. Pappus absent, or scale formed aristiform or coroniform.
6a. Involucral bract throughout or margin scarious; capitula discoid or radiate 7. Anthemideae
6b. Involucral bract foliaceous.
7a. Receptacle usually paleaceous; capitula usually radiate, rarely coroniform; leaves usually opposite .............................................................................. 5. Heliantheae
7b. Receptacle epaleaceous; capitula radiate; leaves alternate ........ 6. Helenicae
2b. Anthers acute, hastate or caudate at base; leaves alternate.
8a. Style arms fine, long, cylindrical, subulate, acuminate, without appendage; capitula discoid, homogamous .............................................................................................................. 1. Vernonieae
8b. Style arms not finely subulate; capitula discoid, ray florets absent, or radiate with ray florets.
9a. Style tip with a thickened hairy node, above branched or simple; capitula homogamous, sometimes with sterile ray florets ................................................................................. 10. Cynareae
9b. Style tip without hairy node, arms truncate or with triangular appendage.
10a. Capitula discoid or radiate; corolla irregularly parted or bilabiate, or marginal florets ligulate 11. Mutisieae
10b. Disc florets of capitula bifid, not bilabiate.
11a. Pappus bristle filiform, sometimes absent; capitula discoid, or radiate with ray florets 4. Inuleae
11b. Pappus bristle absent; capitula radiate ....................................... 9. Calenduleae