Abstract: According to the high level of nitrogen application and the low Nitrogen fertilizer utilization rate，eight different treatments with different fertilizer application，no nitrogen fertilization( N0) ，conventional fertilization nitrogen( CFN) ， 80% chemical fertilizers and 20% farmyard manure( 80F + 20M) ， 80% chemical fertilizers，30% chemical fertilizers and 50% farmyard manure( 30F + 50M) ， 30% chemical fertilizers and 50% controlled-release nitrogen( 30F + 50S) ， 30% chemical fertilizers and 50% green manure nitrogen in early rice and 80% chemical fertilizers and fresh rice straw in later rice，and 80% controlled-release nitrogen with their replications were examined．Each P and K application rate was the same in all the treatments． Analysis of the dynamics of soil nutrient and the relationship between the crop yields in different growth stages． The results showed that: Under the 30F + 50M treatment and 30F + 50S treatment， the grain yield higher the 80F 4． 7% and 5． 2% respectively，equal to CFN treatment． The rest of the treatment of nitrogen reduction was similar to 80F of yield． Under the 30F + 50M treatment， the soil organic mater content and available P reached the maximum in the whole grows period and the available N reached the maximum at the active tillering stage and the mature stage． Under the 30F + 50S treatment， the available N reached the maximum at the heading stage． Under the N0 treatment， the soil available K reached maximum in the whole grows period． The soil total nitrogen，available N content，available P content and rice grain yield significant positive correlation，and the soil available K content is a significant negative correlation with yield． The soil organic matter content，available P content and available K content in different growth periods are significantly positive correlation respectively． Therefore，chemical fertilizers and farmyard manure or chemical fertilizers and controlled-release nitrogen could improve soil available nutrient content at different growth periods and increase yield or reached traditional fertilization level．

Key words: Rice, Nitrogen-reduction, Yield, Soil fertility

CLC Number: 

• S158.3

• S511.06