The term rice refers to the grain-producing species of grass with narrow leaves that grows about 60 to 180 centimeters tall. There are 20 wild species and two cultivated species of rice. Rice is native to Africa, India, and China. The word rice has Indo-Iranian origins. Rice is a major staple food, and rice production is a major source of income and employment for millions of people in 144 countries worldwide. Rice is a superior source of energy among the cereals. Polished rice, however, has shown vitamin A and mineral deficiencies, causing weak immune systems in children in countries where rice is a major staple food. Parboiled rice, in contrast, is nutritionally superior to polished rice. In south and southeast Asia, rice is cultivated under submerged conditions in paddies. The practice of intensive rice monoculture in Asia has caused problems of waterlogging, salinity buildup, and nutrient depletion. Rice cultivation Rice ...