Rice (Oryza sativa L.) is a staple food of more than 60%
of the world’s population and provides more calories per
hectare than any other crop. It is estimated that more
than 40% world’s population use rice as major source of
calories (Munson, 1982) should use recent data. In India,
rice is extensively grown on an area of 42 million ha with
a production and a productivity of 117 million tonnes and
2.91 t ha-1 respectively (Anonymous, 2003a).