DETERMINATION OF THE YIELD POTENTIAL AND ASSOCIATED TRAITS IN RICE

摘要

Production technologies of growing semi-dwarf crop genotypes under a high input of resources started in the mid 1960s during the Green Revolution, leading to significant worldwide increases in crop yields and grain production. However, since the mid-1980s when the Green Revolution expansion was drawing to a close, increases in crop yields have been decreasing. In rice, the average annual rate of yield increase in 1990s sharply declined to 1.1% from that of 2.7% in the 1980s (Horie et al., 2004). Sucha stagnation of the crop yield increase reflected the remarkable decline in the per capita grain production in the world from the mid-1980s (Mann, 1999). One of the causes for the stagnation of the crop yield was the slower rate of yield potential improvement under optimum management practices. In the tropics, the rice yield potential has not increased substantially in the past three decades since the Green Revolution began, and the gap between yield potential and farm yields has narrowed (Peng et al.,1999). Similar phenomena have also been reported for wheat and maize (Sinclair, 1999).