But as the limitations of the Green Revolution become harder and harder to ignore, biotechnologies and biotech companies are being courted by public sector research institutions to offer solutions to the sustainability problem. Despite the hype, it seems that biotech's promises are little more than Green Revolution solutions in fancy new packaging. Adapting it to grow in a huge variety of different environments from Himalayan hilltops to tropical lagoons, farmers have nurtured a vast array of varieties of the world's number one staple to meet their families' needs. In contrast, in industrialised countries outside Japan, annual per capita intakes do not exceed the meagre 10 kg eaten by US dwellers, although rice is found in a number of processed foods and feeds. The result of the continuous interaction between farmers' needs and the environment has been the huge heritage of rice genetic diversity, which has been estimated in more than 140,000 varieties of O. sativa , including land races and improved varieties.
Some varieties grow well during droughts, others can withstand certain pests.
Some produce long slender grains, others short, round ones. No less impressive are the technologies that have accompanied rice. In tropical countries rice ecosystems are extremely diverse in species. For example, Filipino and Indonesian ricefields have been found to contain more than 600 and 760 invertebrate taxa respectively. In many rice lands flooded by estuarine waters, fish and shrimps that arrive with the tide are often cultured alongside.