Effects Of Different Nitrogen Application Modes On Agronomic Characters And Taste Quality Of Rice In Jilin Province

?Research purposes?Rice yield and quality are two important research directions in rice breeding.Research on the correlation and influencing factors between yield and quality is the basis for high-yield and high-quality breeding,and nitrogen fertilizer is an important factor affecting rice yield and rice quality.Choosing the appropriate nitrogen fertilizer level and nitrogen fertilizer management model according to the different characteristics of the varieties,and rational application of nitrogen fertilizer can not only greatly increase rice yield,but also effectively improve rice quality,which is an important way to improve rice production efficiency.This experiment studied the effects of different nitrogen fertilizer management models under different nitrogen levels on the yield,agronomic traits,nutritional quality and taste quality of two japonica rice varieties,Jijing 528 and Qiuguang.The amount of nitrogen and the mode of nitrogen application make it possible to improve the quality of rice as much as possible under the premise of little impact on yield.?Methods?The experiment was conducted in the test field of the Rice Research Institute of Jilin Academy of Agricultural Sciences in 2019.The experiment set three nitrogen levels: pure nitrogen A: 75 kg / hm2,B: 125 kg / hm2,C: 175 kg / hm2.The treatment mode of nitrogen fertilizer is treated,the ratio is base fertilizer: tiller fertilizer: ear fertilizer:(1)7: 3: 0,(1)5: 3: 2,(3)3: 3: 4.The experiment was designed with random blocks and repeated 4 times.The experiment adopts 12 rows of areas,each planting area has 6 rows,the row length(pond width)is 10 meters,about 0.2 hectares of test area(4 ponds,0.05 hectares per pond),and the transplanting density is 9 cun *6 cun.The experimental material Jijing 528 is a high quality variety with few tillers and large spikes selected by the Academy of Agricultural Sciences of Jilin Province,and Qiuguang is a variety of Japanese japonica rice introduced in the early years of Jilin Province.?Results?The main test results are as follows: 1.Effects of different nitrogen application patterns on rice agronomic traits and yield.From the perspective of nitrogen level,under the conditions of this experiment,with the increase of nitrogen application level,the effective tiller number and plant height of rice both increased significantly,and the rice yield also gradually increased.At the highest nitrogen level C(pure nitrogen 175 kg / hm2),the yield was the highest,all of which showed C> B> A.The increase in nitrogen application level changed the components of rice yield,and both the thousand kernel weight and seed setting rate decreased,but the spike length and average spike grain number increased significantly,resulting in increased yield.At high nitrogen levels,the low-tiller rice variety Jijing 528 began to slightly fall,while the multi-tiller rice variety Qiuguang fell seriously.The analysis believes that if the nitrogen application level is further increased,it will induce large-scale lodging and affect the yield and quality.From the perspective of nitrogen fertilizer application,basal fertilizer: tiller fertilizer: ear fertilizer is 3: 3: 4 optimal,reduce the basal fertilizer while increasing the application of ear fertilizer,before nitrogen moves backward,the effective number of tillers and plant height have increased,rice yield A substantial increase.However,the multi-tiller spikelet type will fall down when there is too much ear fertilizer,resulting in a reduction in yield.A 5: 3: 2 nitrogen fertilizer management model should be used.2.Effects of different nitrogen application modes on rice quality.From the perspective of nitrogen level,with the increase of nitrogen level in rice nutritional quality,the amylose content in rice gradually decreases.The protein and fat content of the low-tiller variety Jijing 528 is less affected by the nitrogen level,and more tillers.The protein content of the type variety Qiuguang is greatly affected by the nitrogen level.From the perspective of taste quality,the low-tiller variety Jijing 528 had the highest taste quality at medium nitrogen level B(pure nitrogen 125 kg / hm2),and the multi-tiller variety Qiuguang had the highest taste quality at low nitrogen level A(pure nitrogen 75 kg / hm2).Excessive application of nitrogen fertilizer will cause a decrease in taste quality.From the point of view of nitrogen fertilizer application,the effect of backward nitrogen on nutritional quality is less,but it will reduce the quality of rice taste.?Conclusions?According to the comprehensive comparison and analysis of the experimental results,for the Jilin 528 high-quality japonica rice variety with small tillers and large spikes,in order to take into account the rice taste quality and yield,while ensuring the yield,the nitrogen fertilizer management model with higher taste quality is selected.The reasonable nitrogen application level should be between 125 kg / hm2-175 kg / hm2,the application of basic fertilizer: tiller fertilizer: ear fertilizer = 3: 3: 4 nitrogen fertilizer management model.Compared with other models,this model has the highest yield and no significant changes in nutritional quality.Although the taste quality is slightly lower but there is no significant difference,it can optimize rice quality while having the least impact on yield.The reasonable nitrogen application level of the multi-tiller spikelet variety should be between 125 kg / hm2-175 kg / hm2,and the basic fertilizer: tiller fertilizer: ear fertilizer = 5: 3: 2 nitrogen fertilizer operation model is used.Appropriate amount of ear fertilizer ensures high rice quality and harmonizes yield and quality.