The Rice plant (Oryza sativa) belongs to Poaceae (the Grass family). It is an annual grass that has its origin in the species Oryza perennis, native to northwest India east to Yunnan of China. Asian rice plant (Oryza sativa) was introduced into Japan in ancient days. It is devided into 3 species, Indica (Long-grain rice), Javanica (Large-grain rice) and Japonica (Short-grain rice). Indica species has weighting over 80 % of world rice production, meanwhile Japonica species has less than 15 %.