Effects of Nitrogen Application Rate at Different Stages and Planting Pattern on Japonica Rice Yield Characters and Nitrogen Use Efficiency in Paddy Field of Southern Henan Province

PENG Ting; HAN Yuen; ZHANG Jing; DU Yanxiu; LI Junzhou; SUN Hongzheng; ZHAO Quanzhi

doi:10.15933/j.cnki.1004-3268.2017.11.004

Abstract：The effects of nitrogen application rate at different stages and planting pattern [artificial transplanting(AT) and mechanical transplanting(MT)] on rice yield and nitrogen use efficiency were studied under the precise and quantitative cultivation with the split plot experiment design in paddy field in southern Henan province.This study could provide a certain theoretical foundation for rice production in paddy field in southern Henan province.The results indicated that under the two different planting patterns,different nitrogen ratios(the ratios of base tillering fertilizer to panicle fertilizer were 4∶ 6,5∶ 5,6∶ 4,and 7∶3) could significantly improve the grain number per spikelet and grain yield of rice.In the AT way,the nitrogen proportion of 6∶4 had the highest yield,which increased by 27.65％ compared with the control without nitrogen fertilizer,while the nitrogen proportion of 7∶3 in the MT way had the highest yield,which increased by 115.55％ compared with the control.In addition,the production of MT was higher than that of AT,but the difference did not reach the significant level.In case of AT,effective panicles and grain number in 6 ∶ 4 were higher than those of other treatments;while in MT,effective panicles were highest in 5∶5,and grain number was highest in 7∶3;and the seed setting rate and 1 000 grain weight were highest in control under AT and MT.The dry matter accumulation at the mature stage in AT reached the maximum at the nitrogen ratio of 6∶ 4.At the heading and flowering stage,the nitrogen content in leaves and stems was higher with nitrogen ratios of 6 ∶ 4 and 7 ∶ 3 under AT and MT,respectively.The MT had a higher level than AT in the nitrogen use physiological efficiency under different nitrogen ratios,and the best nitrogen ratio was 7∶3 for the two planting methods.The AT had the highest partial factor productivity at the nitrogen ratio of 6∶ 4,but the MT was 7∶ 3.The highest nitrogen use for 100 kg grain was 5∶5 and 6∶4 in AT,while 6∶4 in MT.Therefore,there was a significant effect on yield with different nitrogen proportions under different cultivation ways.The best nitrogen ratios for AT and MT were 6∶4 and 7∶3 respectively,under which AT and MT had the highest yield and nitrogen use efficiency.