Effect Of Organic Fertilizer Replacing Part Of Chemical Fertilizer On Reducing Fertilizer And Increasing Efficiency Of Maize In Northern Xinjiang

?Objective?There are issues of excessive application of chemical fertilizers and low use efficiency of straw resources in maize production in northern Xinjiang.It is hoped that organic fertilizer replacement technology will be utilized for reducing chemical fertilizer application and increase efficiency.Through field experiments,the effect of different organic fertilizer replacement ratios and different organic replacement reducing fertilizer patterns on maize growth,yield,and soil physicochemical properties was studied to find suitable replacement ratios and organic replacement and reduction methods;Study the laws of decomposition and nutrient release of maize straw under different replacement ratios,formulate reasonably comprehensive application measures of straw returning and organic substitution,and provide a scientific basis for replacing organic fertilizer with reduced fertilizer in maize production in northern Xinjiang.?Method?The experiment was conducted in the Modern Agricultural Technology Demonstration Park of Yining County,Xinjiang in 2018.The experimental plant was maize?Zea Mays L,cv,xinyu50?.The effects of chemical fertilizer reduction on maize were studied in the experiments of different organic fertilizer replacement ratio under nutrient conditions?CK:no fertilizer;CF:conventional fertilization;8%OF:organic fertilizer replacing 8%nitrogen fertilizer;16%OF:organic fertilizer replacing 16%nitrogen fertilizer;24%OF:organic fertilizer replacing 24%nitrogen fertilizer?,different organic replacement reducing fertilizer patterns?CK:no fertilizer;CF:conventional fertilization;HF:humic acid organic fertilizer+reduction of 10%N fertilizer+PK fertilizer;BN:fertilizer synergist+reduction of 10%N fertilizer+PK fertilizer;OF:commercial organic fertilizer+reduction of 10%N fertilizer+PK fertilizer?,and commercial organic fertilizer replacement demonstration?CK:no fertilizer;CF:conventional fertilization;MNPK:commercial organic fertilizer+chemical fertilizer?,and the appropriate organic fertilizer replacement ratios and organic replacement reducing fertilizer pattern were determined;The nylon bag method was used to study the laws of decomposition and nutrient release of maize straw under different organic fertilizer replacement ratios,and the decomposition and nutrient model was established for dynamic monitoring and prediction.?Result??1?8%OF,16%OF and 24%OF treatments compared with CF treatment,promoted the growth and development of maize,and increased plant height,stem diameter and SPAD value of leaves;improved the ear traits and yield components of maize,the yields were significantly increased?P<0.05?by 17.56%,28.50%and 9.82%,respectively,and net income increased by 1130.64 yuan/hm²,1303.32 yuan/hm² and-2774.55 yuan/hm²,respectively;improved the physicochemical properties of soils at maturity stage.Through model analysis,the optimal organic fertilizer replacement ratio of 9.5%and its fertilization scheme was determined.?2?During the whole decomposition process,8%OF,16%OF,and 24%OF treatments promoted decomposition and nutrient release of maize straw,the decomposition and nutrient release of different treatments were 8%OF>16%OF>24%OF>CF>CK,and the decomposition and nutrient release of straw was fast in the early stage?0²0d?and later in the period?20¹00d?;Through the model?y=a·x^b?analysis of nutrient release rate,the days of complete release of C,N,P and K in straw were predicted to be 206²22d,167¹93d,153¹81d and 85⁹0d,respectively,which verified the nutrient release law of K>P>N>C in this experiment.?3?HF,BN and OF treatments compared with CF treatment,promoted the growth and development of maize,and increased plant height,stem diameter and SPAD value of leaves;improved the ear traits and yield components of maize,the yield increased?P<0.05?by11.12%,6.47%and 14.43%,respectively,and net income increased by 217.24 yuan/hm²,564.99 yuan/hm² and-506.46 yuan/hm²;increased the content of alkaline N,available P,available K in the soil during the growth stage of maize;increased recovery efficiency?RE?,partial factor productivity?PFP?and agronomic use efficiency?AUE?.Among them,the recovery efficiency of N fertilizer was significantly increased by 8.15%,9.34%and 14.08%,and K fertilizer was significantly increased by 15.92%,21.13%and 29.36%,respectively.?4?NPK and MNPK treatments compared with CK,promoted the growth and development of maize,and increased plant height,stem diameter and SPAD value of leaves;improved the ear traits and yield components of maize;the yield increased by68.53%⁸3.47%,and net income increased by 0⁴19.58 yuan/hm²;the content of alkaline N,available P,available K and organic matter in soil increased by 2.73%²3.29%,23.19%³9.30%,13.86%⁹5.76%and 28.10%⁴5.13%,increased soil moisture,reduced soil pH and soil bulk density.?Conclusion??1?Suitable organic fertilizer replacement ratios?8%OF and 16%OF treatments?promoted maize growth and development,increased yield and economic benefits,fertilize the soil,and determined the optimal organic fertilizer replacement ratio of 9.5%and its fertilization scheme through model analysis,which provides the feasibility basis for the application of organic fertilizer replacement in maize production.?2?According to the laws of decomposition and nutrient release of straw,a comprehensive management strategy for reasonable straw return and fertilization in maize planting at a recommended replacement ratio of 9.5%was proposed:organic fertilizer and straw were applied as the base fertilizer,and the amount of chemical fertilizer in the base fertilizer was reduced,and according to the law of nutrient absorption of maize,K fertilizer was reduced or delayed,and NP fertilizers were added after jointing stage.?3?HF and BN treatments promoted maize growth and development,increased yield and efficiency,fertilizer utilization ratio and improved soil physicochemical properties,and provided economically feasible fertilization schemes and technical support for reducing fertilizer and increasing efficiency in maize production.?4?Commercial fertilizer replaces partial chemical fertilizer under the condition of equal nutrients to reduce the amount of fertilizer used by 72.0 kg/hm²?N,P₂O₅ and K₂O decreased by 30.0 kg/hm²,33.0 kg/hm²and 9.0 kg/hm²,respectively?,and promote the growth of maize,increase maize yield and economic benefits,and improve soil physical and chemical properties,which is an economic and feasible method to promote the reducing fertilizer and increasing efficiency of maize.