Oryza sativa species

Rice belongs to the genus Oryza in the family Poaceae. Oryza sativa is the main species cultivated worldwide. Oryza sativa (Asian or paddy rice), is grown primarily in the humid topics and subtropics, with some cultivation on flooded upland sites, such as central California.

Another less important rice, Oryza glaberrima (African rice), is grown in east Africa, but is being replaced by Oryza sativa.

Rice is consumed as a grain almost exclusively by humans, supplying 20% of daily calories for the world population.

The cultivated species of Oryza sativa evolved during several thousand years of cultivation in widely different geographic and agroclimatic regions, producing a multitude of forms and varieties.

For producing rice, a tremendous amount of water is used for the rice irrigation under the traditional irrigation technique called as a continuous deep flooding irrigation technique. In this technique, the paddy fields are inundated all the time starting from transplanting until nearly harvesting at certain water depth that varies from 50 mm to 100 mm.
Oryza sativa species