Improving rice (Oryza sativa L.) grain yield per unit land area
is the only way to achieve increased rice production because
of the reduction in area devoted to rice production (Cassman,
1999). Irrigated rice contributes >75% of total rice production,
although it accounts for about 55% of total rice area. Rice varieties
with higher yield potential must be developed to enhance the
average farm yields of irrigated rice to increase the world’s total
rice production.