Watermelon

Watermelon citrullus lanatus var.Lanatus is a scrambling and trailing vine in the flowering plant family cucurbitaceae.The species originated in southern Africa and there is evidence of it's cultivation in Ancient. It is grown in tropical and sub-tropical areas worldwide for it's edible fruit, also known as watermelon, which is a special kind of berry with a hard rind and no internal division, botanically called a pepo. The sweet, juicy flesh is usually deep red to pink, with many black seeds. The fruit can be eaten raw or pickled and the rind is edible after cooking.
Kingdom - plantar
(Unranked) - Angiosperms
(Unranked)- Eudicots
(Unranked) - Rosids
Order - Cucurbitaceae
Genus - Citrullus
Species - C.Lanatus
Variety - Lanatus
Trinomial name: Citrullus Lanatus Var. lanatus
Considerable breeding effort has been put into disease resistant varieties and into developing a " seedless" strain with only digestible white seeds. Many cultivars are available that produce mature fruit within 100 days of planting the crop.
         Description
The watermelon is a large annual plant with long, weak, trailing or climbing stems, which are five angled (five sided) and up to 3m (10ft) long.Young growth is densely wooly with yellowish- brown hairs which disappear as the plant ages. The leaves are large, coarse, hairy pinnately-lobed and alternate, they get stiff and rough when old. The plant has branching tendrils. The white to yellow flowers grow singly in the leaf axils corolla is white or yellow inside and greenish-yellow on the outside. The flowers are unisexual, with male and female flowers occurring on the same plant (monoecius). The male flowers predominate at the beginning of the season, the female flowers which develop later, have inferior ovaries. The styles are united into a single column. The large fruit is a kind of modified berry called pepo with a thick rind (exocarp) and fleshy center (mesocarp and endocarp).Wild plants have fruits up to 20cm (8 in) in diameter while cultivated varieties may exceed 60cm (24 in). The rind of the fruit is mid-to dark green and usually mottled or stripped, and the flesh containing numerous pips spread throughout the inside, can be red or pink (most commonly), orange, yellow, green or white.
                                                    History
The watermelon is a flowering plant thought to have originated in southern Africa, where it is found growing wild, it reaches maximum genetic diversity there, with sweet, bland and bitter forms. In the 19th century, Alphonse de candolle considered the watermelon to be indigenous to tropical Africa. Citrullus colocynthis is often considered to be a wild ancestor of the watermelon and is now found native in north and west Africa. However, it is has been suggested on the basis of chloroplast DNA investigations that the cultivated and wild watermelon diverged independently from a common ancestor, possibly c.e cirrhosis from Namibia.