Irrigated rice ecosystems are those areas that have assured irrigation for one or more crops per year. About 57% of world area under rice (about 43 million ha) area under irrigation. Yield levels achieved are 4-7 t ha^-1 crop^-1. There are three rice environments in this ecosystem, namely, irrigated with favorable temperature, irrigated with unfavorable temperature-tropical zone and irrigated with unfavorable temperature-temperate zone.