Rice

Rice is the seed of the grass species Oryza Sativa (Asian rice) or Oryza glaberrima (African rice).As a cereal grain,it is the most widely consumed staple food for a large part the world's human population, especially Asia.It is the agricultural commodity with the third highest worldwide productuction (rice,741.5 million tonnes in 2014),after sugarcane (1.9 billion tonnes) and maize (1.0 billion tonnes).
Since sizeable portions of sugarcane and maize crops are used for purposes other than human consumption,rice is the most important grain with regard to human nutrition and  caloric intake, providing more than one-fifth of the calories consumed worldwide by humans.There are many varieties of rice and culinary preferences tend to vary regionary.
 Rice,a monocot is normally grown as an annual plant, although in tropical areas it can survive as a perennial, and can produce a ration crop for up to 30years.Rice cultivation is well suited to countries and regions with low labor costs and high rainfall, as it is labor intensive to cultivate and requires ample water. However, rice can be grown practically anywhere, even on a steep hill or mountain area with the use of water-controlling terrace systems. Although it's parent species are native to Asia and certain parts of Africa, centuries of trade and exportation have made it commonplace in many cultures worldwide.
 The traditional method of cultivating rice is flooding fields while, or after setting the young seedling. This simple method  requires sound planning and servicing of the water damming and channelling, but reduces the growth of less robust weed and pest plants that have no submerged growth state and deters vermin. While flooding is not mandatory for the cultivation of rice, all other methods of irrigation require higher effort in weed and pest control during growth periods and a different approach for fertilizing the soil.
 The name wild rice is usually used for species of the genera zizania and porteresia, both wild and domesticated, although the term may also be used for primitive uncultivated varieties of Oryza.
Etymology

First used in English in the middle of the 13th century, the word "rice" derives from the old French ris, which comes Italian riso, in turn from Latin Oriza, which derives from the Greek "Oruza". The Greek word is the source of all European words (CF. welsh reis, German Reis, Lithuanian ryziai, serbo-croatian riza, polish ryz, Dutch rijst, Hungarian rizs, Romanian orez).
 The origin of the Greek word is unclear, It is sometimes held to be from the Tamil word (arisi), or rather old Tamil arici. However, Krishna Mufti disagrees with the notion that old Tamil arici is the source of the Greek term, and proposes that it was borrowed from descendants of proto-Dravidian, .... instead. Mayrhafer suggested that the immediate source of the Greek word is to be sought in old Iranian words of the types *vriz_ or *vrinj-(source of the modern Persian word Berenj) but these are ultimately traced back to indo-Aryan(as in Sanskrit vrihi) and subsequently to Dravidian.