Floating rice
Deepwater rice are varieties of rice (Oryza sativa) grown in flooded conditions with water more than 50 cm (20 in) deep for at least a month. More than 100 million people in South and Southeast Asia rely on deepwater rice for their sustenance. Two adaptations permit the rice to thrive in deeper water, floating rice and traditional talls. Traditional talls are varieties that are grown at water depths between 50 and 100 cm (20 and 39 in) and have developed to be taller and have longer leaves than standard rice. Floating rice grows in water deeper than 100 cm through advanced elongation ability. This means when a field where rice is growing floods, accelerated growth in the internodal of the stem allows the plant to keep some of its foliage on top of the water. The O. s. indica cultivar is the main type of deepwater rice, although varieties of O. s. japonica have been found in Burma, Bangladesh, and India.
Deepwater rice is a staple food grown on roughly 90,000 km2 (35,000 sq mi) of land. The main areas where it is grown are in South and Southeast Asia, where more than 100 million people rely its production for their livelihood. In South Asia or South-East Asia, the main area deepwater rice is grown in is the Brahmaputra valley in Assam, a state in Northeast India and other Northeast Indian states. In Southeast Asia, the main areas of cultivation are in Burma in the Irrawaddy Delta, in Thailand in the Chao Phraya and Mekong in Vietnam and Cambodia. In these countries, deepwater rice accounts for more than 25% of the land used to grow rice.
Deepwater rice is cultivated less in West Africa than in Asia, with about 4,700 km2 (1,800 sq mi). Areas it is grown include the Niger River basin. Some areas in Ecuador grow deepwater rice.
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