Response of Rice (Oryza sativa L.) to Increasing Temperature and Atmospheric CO2

Rice (O.

sativa

and

O. glaberrima

) is one of the world most important cereal food crops, particularly in Asia and increasingly so in Africa and Latin America. Rice provides a substantial portion of the dietary requirements of nearly 1.6 billion people, with another 400 million relying on rice for quarter to half of their diet (Swaminathan 1984). Rice is cultivated as far north as Manchuria in China (39° 53’N) and far south as New South Wales in Australia (28° 81’S) (Khush 2005), either as an upland (aerobic) or wetland (irrigated, rainfed and deepwater) crop. Upland rice cultivation covers 17Mha, while wetland rice is cultivated on 131Mha, contributing about 30 and 70%, respectively, of the total rice production in the world (Dubey 2001). Rice occupies 23% of the total cultivated area under cereals in the world, of which 89% is in Asia (FAO 2003). Hence, Asia produces 523MT of rice (91% of the world production) (Dubey 2001), on which nearly half of the world’s population depend for food and livelihood (Carriger and Vallee 2007). Since the world population is increasing at 1.17% annually, an annual increase in rice production by 0.6–0.9% is required until 2050 (Carriger and Vallee 2007) to meet the anticipated demand.