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International issues
Past scientific research on various aspects of
rice cultivation and on the rice plant itself
has been responsible for remarkable gains
in the productivity of rice-farming systems.
However, rice production must increase if it is to
keep pace with population growth. The scope for
expansion of rice-growing areas is limited. Most
of the increase will have to come from improved
plants and from production methods that are
more efficient yet more environmentally
sustainable.
Here, we look at several major issues:
dealing with a future in which less water is
available, ways to increase the yield potential of
the rice plant, steps toward making rice more
nutritious, forecasting and dealing with the
effects on rice plants and ecosystems of global
climate change, reducing greenhouse gas
emissions from rice fields, the new research area
of functional genomics, biotechnology, and
integrating knowledge through crop modeling.
The looming water crisis
The amount of water needed to produce one ton
of rice would fill between two and three
Olympic-sized swimming pools.
Nearly 90% of fresh water diverted for
human use in Asia goes to agriculture and, of
this, more than 50% is used to irrigate rice.
China’s Yellow River, which flows for 4,600 km
through some of Asia’s richest farmland, has run
dry nearly every year since 1972. In South Asia,
the Ganges and Indus rivers have almost no
outflow to the sea in the dry season.
Too much water or too little
Asia’s water problems are caused partly by the
uneven distribution of water. On the one hand,
about half of China receives less than 400 mm of
rainfall a year, and extensive areas of
northwestern, central, and southern Asia are
drought-prone. On the other hand, the Ifugao rice
Precious irrigation water in Bangladesh.
International issues 31