Morphology og SUNFLOWER

Local name: Surjyamukhi.

Botanical name: Helianthus annuus

Family: Compositae

Plant type: An annual, erect, and a herbaceous plant growing to a height of 1.5 to 6.0 m.
Root: Has a tap and branched root system.

Stem: Stem is 2.5 to 7.5 cm in diameter, rough hairy or hispid, usually without branches terminating in a capitulum.

Leaves: Simple, alternate with stout petioles, somewhat lanceolate in shape and about 5 to 25 cm long and two thirds as wide. Leaves are rough on both surfaces and irregularly toothed on the margins.

Inflorescence: Sunflower is protendrous, in which the male and female parts mature at different times. Racemes, head or capitulum consisting of ray and disc florets. Heads are 10 to 50 cm in diameter with 40 to 80 rays and brown or black disc.

Ray floret: Marginal star shaped ones

Calyx: Either absent or represented 2 or 3 scales superior.

Corolla: 2-5, gamopetalous, ligulate superior, yellow.

Androecium: Absent.

Gynoecium: 2, bicarpellary, syncarpous, ovary inferior, unilocular, single base ovule, basal placentation, style single, and stigma bifid.  

Fruit: Cypsela.

Floral formula: %  0 K0 (2-5 scales), C(5), A 0, G(2).

Disc floret: Central tubular ones.

Calyx: Either absent or represented 2 or 3 scales superior.

Corolla and androecium: 5, syngenesious, epipetalous, alternate to petals, filaments free, anther bicelled, and superior.
  
Gynoecium: 2, bicarpellary, syncarpous, ovary inferior, unilocular, single base ovule, basal placentation, style single, and stigma bifid.  

Floral formula: Br.  0 K0 (2-5 scales), C (5), A (5), G (2).

Seeds: A single flower head produces 350 to 2000 seeds. Seeds are generally less than 1.5 cm long pointed at the base and round at end. Color of seeds may be white, black or black white with stripes.