Oryza rufipogon is a species of flowering plant in the family Poaceae. It is known as brownbeard rice, wild rice, and red rice. In 1965, Oryza nivara was separated off from O. rufipogon. The separation has been questioned, and now many sources consider O. nivara to be a synonym of O. rufipogon. O. nivara may be treated as the annual form of O. rufipogon.
It is native to East-, Southeast- and South- Asia. It has a close evolutionary relation to Oryza sativa, the plant grown as a major rice food crop throughout the world. Oryza nivara is a possible wild progenitor of cultivated rice. Both have an AA genome.
Description
For those who accept Oryza nivara as a separate species, it is an annual, short to intermediate height (usually <2 metres (6 ft 7 in)) grass; panicles usually compact, rarely open; spikelets large, 6–10.4 millimetres (0.24–0.41 in) long and 1.9–3.4 millimetres (0.075–0.134 in) wide, with strong awn (4–10 centimetres (1.6–3.9 in) long); anthers 1.5–3 millimetres (0.059–0.118 in) long. It grows in shallow water up to 0.3 metres (1 ft 0 in), in seasonally dry and open habitats. It is found growing in swampy areas, at edge of pond and tanks, beside streams, in ditches, in or around rice fields.
