Rice is a cereal foodstuff which forms an important part of the diet of many people worldwide. Domesticated rice comprises two species of food crops in the Oryza genus of the Poaceae ("true grass") family, Oryza sativa and Oryza glaberrima (Crawford et al., 1998). Rice is grown as a monocarpic annual plant, although in tropical areas it can survive as a perennial and can produce a ratoon crop and survive for up to 20 years (International Rice Research Institute 2008). Smith et al (1998) reported that Rice provides more than one fifth of the calories consumed worldwide by humans. In the...