Effect Of Different Deep Side Fertilizer Usage On Rice Growth-development And Nitrogen Use Efficiency

The experiment was carried out in the rice experimental field of Baicheng Academy of Agricultural Sciences,Jilin province in 2020.A regional experiment design was adopted and jigeng 816 was used as the test variety.Five treatments were set up in the experiment.Blank control(CK1),conventional fertilization(CK2),side depth fertilization with 100kg/hm~2pure nitrogen(CS1),150kg/hm2 pure nitrogen(CS2),200kg/hm~2pure nitrogen(CS3)were used to investigate the effects of different side depth fertilizer application rates on rice growth and nitrogen use efficiency.Finally,the suitable amount of lateral depth fertilizer was selected to provide technical and theoretical support for rice planting in the west of Jilin Province.The results of this experiment are as follows:1.Compared with CK2 treatment,lateral deep fertilization increased tiller number and effective panicle number per unit area of rice.Except for CS1 treatment,plant height and grain number per spike of CS2 and CS3 were higher than those of CK2 treatment,but seed setting rate of CS3 was significantly lower than other treatments,and there was no significant difference in1000-grain weight among different treatments.2.Compared with CK2 treatment,The SPAD value of CS2 and CS3 treatment still remained high after full heading stage.At 20 days after full heading stage,the SPAD value of CS2 and CS3treatment increased by 17.21%and 18.72%,respectively,compared with CK2 treatment.There was no significant difference between CS2 and CS3 treatment.The SPAD value of CK2treatment was significantly different.In the mature stage,SPAD value of CS2 and CS3 treatments increased by 26.73%and 11.00%compared with CK2 treatment,respectively,and there was no significant difference between CS2,CS3 and CK2 treatment.3.The leaf area index at full heading stage was CS2>CS3>CK2>CS1,The LAI of CS1 and CS2 treatment was 24.34%higher than that of CK2 treatment,and there was no significant difference between CS2 and CK2 treatment.The leaf area index of CS3 was 23.31%higher than that of CK2,and there was no significant difference between CS3 and CK2.There was no significant difference between CS2 and CS3 treatments.4.Compared with CK2 treatment,the dry matter accumulation of CS1,CS2 and CS3 was12.45%higher than CK2 treatment,10.87%higher than CK2 treatment,and 14.22%higher than CK2 treatment.The differences between CS1,CS2,CS3 and CK2 treatment were not significant.5.Compared with CK2,side deep fertilization increased the nitrogen accumulation of rice,and the nitrogen accumulation of CS2 and CS3 was 62.39%and 38.34%higher than that of CK2,respectively.The nitrogen accumulation of CS1 was lower than that of CK2,and the difference of nitrogen accumulation between CS2,CS3 and CK2 reached a significant level.The uptake and utilization rate of nitrogen fertilizer in CS1 was 36.57%,and that in CK2 was23.18%,which was significantly higher than that in CK2.The nitrogen agronomic efficiency of CS1 and CS2 treatments was 11.85(kg/kg)and 6.36(kg/kg)higher than that of CK2treatment,respectively,and the difference between CS1,CS2 and CK2 treatment was significant.The nitrogen agronomic efficiency of CS3 treatment was 3.52(kg/kg)lower than CK2 treatment,and the difference was significant.The nitrogen partial productivity of CS1 and CS2 was 84.84%and 26.94%higher than that of CK2,and the difference reached a significant level.The nitrogen partial productivity of CS3 was 17.54%lower than that of CK2,but the difference was not significant.The N harvest index of CS1 and CS2 treatment was significantly higher than that of CK2 treatment by 20.33%and 13.24%,and the N harvest index of CS3treatment was significantly lower than that of CK2 treatment by 2.00%.6.The highest yield of different nitrogen application treatments was 8.89t/hm~2in CS2treatment,which was 0.72t/hm~2,0.26t/hm~2and 1.19t/hm~2higher than that in CK2,CS1 and CS3treatment,respectively.There was no significant difference between CS2 and CS1 treatment.The difference between CS2,CK2 and CS3 was significant.The large area of lodging was caused by excessive fertilizer in CS3 treatment.7.In terms of economic benefit,CS1 and CS2 treatments were 1547.75yuan/hm~2and1415.25 yuan/hm~2higher than CK2 treatment,except that CS3 treatment was lower than CK2treatment.To sum up,in the west of jilin province by adopting the technology of deep side fertilizing,one-time on a slow controlled release fertilizer can improve the utilization rate of rice to the absorption of nitrogen fertilizer utilization,agriculture,partial productivity and harvest index,at the same time can improve the yield of rice,in the deep side fertilizing,pure nitrogen,100kg/hm~2～150kg/hm~2net benefits reached a higher level,the increase in income is large.