| The combined application of nitrogen and phosphorus fertilizer and its interaction effect are favorable measures for weight loss,yield increase and quality improvement of winter wheat.In this study,the long-term in-situ trial of different levels of nitrogen and phosphorus in the wheat and jade two-cooked grain field in the Guanzhong Plain was continued since 2009,and five nitrogen application levels were set up:N0,N75,N150,N225,N300 kg/hm~2,four phosphorus application levels:P0,P60,P120,P180 kg/hm~2,and the winter wheat varieties were Pubing 151 and Xinong 979.From 2020 to 2022,the growth dynamics of plants under different nitrogen and phosphorus combined treatment were monitored during the winter wheat growing season,and the effects of different nitrogen and phosphorus combined treatment on nitrogen and phosphorus nutrient uptake,transport and utilization,yield,grain processing quality and nutrient content of winter wheat plants were studied:(1)The combined application of different nitrogen and phosphorus fertilizers significantly affected the leaf area index,SPAD value and biomass index of winter wheat.The leaf area index and SPAD value of winter wheat showed a trend of increasing first and then decreasing in Sui Sheng,while the biomass continued to increase with the advancement of fertility.The growth law of the two cultivars was basically the same under different nitrogen and phosphorus accessories,and the leaf area index of each growth period was basic N225>N300>N150>N75>N0 under different nitrogen application levels,and the leaf area index of each growth period was P180>P120>P60>P0 at different phosphorus application levels.The overall SPAD values were N150≈N225≈N300>N75>N0 at different nitrogen levels,and P60≈P120≈P180>P0 at different phosphorus levels.At different nitrogen application levels,the maximum dry matter accumulation rate in the aboveground part reached the maximum under N225 and N150 treatment,the maximum dry matter accumulation rate at the phosphorus application level was the best under P120 and P180 treatment,and the average dry matter accumulation rate of both varieties reached the maximum under N225 and P180treatment from 2020 to 2022.(2)Nitrogen and phosphorus application significantly increased the accumulation and transport of nitrogen and phosphorus in winter wheat,and there were significant nitrogen-phosphorus interaction effects,nitrogen and phosphorus accumulation and pre-flower transport at flowering and maturity performed best under N225 and P120 treatment,and the grain yield of winter wheat was mainly achieved by the transport of pre-flowering nitrogen and phosphorus in winter wheat,and there were significant nitrogen-phosphorus interaction effects,nitrogen and phosphorus accumulation and pre-flower transport at flowering and maturity performed best under N225 and P120 treatment,and the grain yield of winter wheat was mainly achieved by the transport of pre-flowering nitrogen and phosphorus.Compared with P0,the nitrogen absorption efficiency of Pubing 151 and Xinong 979 was increased by27.5—34.6%,14.3—23.8%,29.3—38.0%,28.6—31.0%,respectively from 2020 to 2022.Compared with N0,the phosphorus absorption efficiency of Pubing 151 and Xinong 979 was increased by 58.9—93.0%,51.7—72.1%,52.9—74.4%and 49.6—79.9%from 2020 to 2022,respectively.(3)Nitrogen and phosphorus application significantly affected the yield and economic benefits of winter wheat,and the yield increase effect of nitrogen application was greater than that of phosphorus application,and the yield of winter wheat was mainly achieved by increasing the number of ears and ear grains by different nitrogen and phosphorus combined application treatments.The number of ears of winter wheat was basically shown as N150≈N225≈N300>N75>N0,the number of ear grains was basically N150≈N225>N300>N75>N0,and the number of panicles was basically P120≈P180>P60>P0under different phosphorus application levels,and the number of panicle grains was P120≈P180>P60>P0.The yield was basically N150≈N225>N300>N75>N0 at the nitrogen level,P120≈P180>P60>P0 at the phosphorus level,and the yield basically reached the maximum value at the N150P120 level under different combined treatments.The total output value,net output value and production-to-investment ratio of winter wheat basically reached the maximum value at the N150 and P120 levels.(4)Nitrogen application and phosphorus application had different effects on the nutrient content of winter wheat grain,nitrogen application significantly increased the nitrogen content,zinc content,iron content and copper content of winter wheat,while phosphorus application significantly increased the nitrogen content,phosphorus content and potassium content of winter wheat.When the nitrogen application rates were 150 kg/hm2 and 225 kg/hm2,the nitrogen,zinc,iron and copper contents of wheat grain were significantly greater than those of other treatments,and the nitrogen,phosphorus and potassium contents of wheat grain were the best when the phosphorus application rates were 120 kg/hm2 and 180 kg/hm2,and the manganese content of wheat grain was also within the recommended range.The content of trace elements in winter wheat grain is specifically manifested as grain manganese≈grain zinc>grain iron>grain copper,except for the lower content of grain zinc and iron than the recommended value,the content of grain copper and manganese is within the appropriate concentration range,but the simple nitrogen and phosphorus combined application treatment on the increase of grain zinc and iron content basically can not meet the needs of the human body suitable concentration,and other cultivation measures are also required.Nitrogen application had a positive effect on the processing quality indexes of winter wheat,while the processing quality index of winter wheat showed a decreasing trend with the increase of phosphorus application.Under different nitrogen application levels,grain protein content performed best under N225 treatment,while it was also maintained at a high level under N150 and N300 treatment,and at phosphorus level,grain protein content in winter wheat performed best under P120 and at phosphorus level,grain protein content in winter wheat performed best under P120 and P180 treatment.(5)According to the simulation of the binary secondary yield effect equation,the maximum yield of the two varieties from 2020 to 2022 was 7170—7548 kg/hm~2,and the corresponding nitrogen application rate was 199—225 kg/hm~2 and the phosphorus application rate was 139—147 kg/hm~2.From 2020 to 2022,the maximum net output value of the two varieties was 11124—13750 kg/hm~2,and the corresponding nitrogen application rate was 195-218 kg/hm~2,and the phosphorus application rate was 124—137 kg/hm~2.The linear segmentation function of protein content and nitrogen application rate under P120 treatment,which is closest to the maximum phosphorus application range,showed that the nitrogen application rate corresponding to the maximum grain protein content was≥163 kg/hm~2.Based on the comprehensive analysis of the simulation results between winter wheat yield,net yield value and protein and fertilizer amount,the nitrogen application range of 163—225 kg/hm~2 combined with 120—147kg/hm~2 of phosphate fertilizer can achieve the overall effect of optimizing the growth of winter wheat,improving the absorption and utilization of nitrogen and phosphate fertilizer,and realizing the purpose of increasing the yield and quality of winter wheat in the Guanzhong Plain and achieving economic efficiency. |
PDF Full Text Request