Sustainability of rice in the global food system - IRRI books

Table 10. Recent trends in population and rice production in the major rice-growing countries
in Asia.
Country
Rice harvested Population growth Growth in rice production
area, 1995 (% yr -1 )
(% yr -1 )
(million ha)
1975-85 1985-95 1975-85 1985-95
China 31.11 1.4
1.4
3.2
0.7
India
42.30 2.2
2.0
2.4
3.1
Indonesia 11.50
2.1
1.7
5.5 2.5
Bangladesh 9.95 2.6 2.0
2.3
1.8
Vietnam
6.77
2.2
2.2 3.6
5.2
Thailand 9.02
2.1
1.4
3.0 0.5
Myanmar 6.20 2.1
2.2 4.6
3.1
Japan
2.12 0.8 0.4
–1.0 –1.1
Philippines
3.76 2.4
2.1
3.5 1.7
South Korea
1.06
1.5 1.0 1.8 –2.2
Asia 132.84 1.9 1.8 3.2
1.7
World 149.09 1.7 1.8 3.1 1.7
1 t ha -1 because of increased pest pressure and frequent cloudy days with below optimal
sunshine (Hossain 1997, Seshu 1988, Seshu and Cady 1984). In humid tropical
regions with a good irrigation infrastructure, the maximum attainable yield is about
to be reached.
Two technologies in the pipeline may help increase land productivity and input
use efficiency, which may aid in further increasing rice supplies. The first is a new
type of rice plant, which the media called “super rice.” In 1988, IRRI scientists began
to design a new plant type that would increase nutrient efficiency, by reducing unproductive
tillers, and increase photosynthesis efficiency through erect and thick leaves
(Khush 1995a,b). Field evaluation of breeding lines for this new plant type has begun,
and initial observations show that the new plant may have a yield advantage of
20–25% over existing modern varieties. Because of poor grain filling, however, this
potential is not being realized. Breeders are now selecting germplasm for improved
grain filling and incorporating genes for disease and insect resistance. Agronomists
are working to develop an optimal planting method, nitrogen application, and weed
control. Further research is also needed to improve grain quality. It may take another
5–10 yr for this technology to reach rice farmers.
The second technology involves developing hybrid rice for tropical regions
(Virmani 1994). Hybrid rice has been grown in China since 1976 and has been the
main source of the growth in rice production since then. Hybrid rice has an average
yield advantage of about 15% over the best inbred varieties. About half of Chinese
rice land is now planted to hybrid rice. The Chinese hybrids, however, were found to
be unsuitable for tropical regions. IRRI began hybrid rice research in 1978 and has
already been successful in breeding lines that show a yield advantage of about 15-
20% over modern inbred varieties under tropical conditions. The IRRI materials are
34 Hossain