In order to reveal the application effect of machine-transplanting with side-deep fertilization of controlled-release blended fertilizer in the southern double cropping rice. Field experiment was conducted for early- and late-rice

and 4 treatments were set up: no nitrogen (N) fertilizer application

conventional fertilization

machine-transplanting with side-deep fertilization by reducing N of 30% and machine-transplanting with side-deep fertilization of controlled-release blended fertilizer by reducing N of 30%. The objective of this study was to compare the effect of machine-transplanting with side-deep fertilization of controlled-release blended fertilizer and conventional fertilization on yield

economic benefits and nutrient uptake and utilization of double-cropping rice

and its reducing potential. Results showed that the yield and economic benefit of machine-transplanting with side-deep fertilization reduced N by 30% of early-rice is higher than those of conventional fertilization by 20.2%~20.9% and 31.8%~32.4%

and its effective panicle

total spikelet and total grain increased by 6.2%~7.5%

20.5%~25.3%

and 27.6%~28.2%

respectively. The yield and economic benefit of machine-transplanting with side-deep fertilization reduced N by 30% of late rice increased by 3.9%~5.2% and 12.6%~13.8%

and its effective panicle

total spikelet

and total grain increased by 15.8%~17.8%

16.8%~18.6% and 14.0%~16.8%

respectively. Hence

the effect of the reduction of side-deep application of controlled-release blended fertilizer is better. Under the condition of machine-transplanting with side-deep fertilization with a N reduction of 30%

the N

P and K uptakes of early-rice with controlled-release blended fertilizer compare with conventional fertilization reduction at harvest time increased by 1.6%

2.5% and 7.9%

respectively

and those of late rice increased by 4.0%

1.1% and 0.9%

and those of early- and late- rice were increased in N recovery efficiency by 4.2% and 10.2%

in N agronomic efficiency by 3.3% and 1.2%

in N partial factor productivity by 0.6% and 1.2%. In conclusion

in the Dongting Lake area

machine-transplanting with side-deep fertilization of controlled-release blended fertilizer can effectively reduce N fertilizer application in the rice field

facilitate the formation of effective panicle

improve N

P

K accumulation and N fertilizer use efficiency

reduce N loss

and thus realize the production of double-cropping rice in terms of saving fertilizer

saving labor

increasing efficiency and increasing yield.