STUDY ON RICE-SPECIFIC BULK BLENDING FERTILIZERS

Results of long-term trials and experimental network over various areas of Guangdong Province showed that the significance of yield increasing effects for rice were generally NKP. Application of P did not result in significant or even no increasing effect at the first crop for a large number of paddy soils, due to relative high concentrations of soil available P. However, yield increasing effects of added N and K became less significance thus resulting in yield decrease for treatments without P application after several crops. On the basis of fertilizer efficiency in various soils with different nutrient supply, nutrient balance of the soil, and the function of yield and fertilizer rates, nutrient formula and application techniques of the product were established for rice-specific bulk blending fertilizer (BBF,N∶P2O5∶K2O=1∶0.35∶0.75～0.85) in Guangdong Province. After repeating field demonstrations in comparison with local fertilizer management and the same rates of imported compound fertilizers(15-15-15), it has been comfirmed that the BBF significantly increased yield, reduced fertilization costs, and saved fertilizer resources.