Adoption of green revolution technologies led to major increases in rice production.  Between 1966 and 2005, population of densely populated low income countries grew by 95% but rice production increased by 139% from 257 million tons in 1966 to 615 million tons in 2005. In spite of these advances in rice production 750 million poor rice consumers go to bed hungry everyday.  Micronutrient deficiencies affect millions of poor rice consumers.  One of the millennium development goals is to reduce extreme poverty and hunger.  Another is to reduce child mortality.  Extreme poverty can be reduced by generating employment and by maintaining the availability of rice at low prices, since poor consumers spend half of their income on food.  Child mortality can be reduced by alleviating micronutrient deficiencies.  Thus, adequate supplies of rice must be maintained as a hedge against price increase.
To meet these challenges we need rice varieties with higher yield potential and dense micronutrients.  Although the yield potential of rice is 10 tons per hectare, farmers on the average get only 5 tons.  To close   the   yield gap, we must develop varieties with more durable resistance to diseases and insects and tolerance to abiotic stresses.  Strategies for increasing the yield potential include: (1) conventional breeding (2) ideotype breeding, (3) hybrid breeding, and (4) genetic engineering.  Conventional and biotechnological approaches are being employed to develop durable resistance to diseases and insects and tolerance to abiotic stresses.  Rice varieties with higher levels of iron and zinc   are being developed.  Natural variation in rice for beta carotene (precursor of vitamin A) does not exist.  A team of Swiss and German scientists has introduced biosynthetic pathway through genetic engineering leading to production of beta carotene in rice endosperm.  The capability of beta carotene production is being transferred into widely grown national  rice  varieties.