Yield formation and cultivation techniques in super high-yielding ratoon rice

Test fields of super high-yielding ratoon rice were established in Youxi county of Fujian in 1998 -2002. The accumulated areas in five years were 1 097. 73 hm2 . The average yield was 10 664 kg · hm-2 in main season and 6 537 kg · hm-2 in ratoon season. The results showed that super high-yield of main crop depended on stable spike numbers and larger spike, the yield had significantly and positively correlation with total dry matter accumulation. The yield of ratoon season mainly depended on more ratoon spikes, 35%-40% of dry matter accumulation in ratoon spikes derived from the transportation of main crop stubble and 60%-65% from the photosynthetic production of the leaves of ratoon rice itself. The key cultivation techniques for super high-yielding ratoon rice included planning suitable planting region, selecting the varieties with high-yielding and high ratoon ability, regulating growth period, cultivating in ridge bed, optimizing fertilizer application and maintaining higher rice stubble.