Research On The Effect And Mechanism Of Yield Increasing For Applying New-type Urea In Winter Wheat And Summer Maize

Inefficient use of nitrogen fertilizer has caused a series of ecological and environmental problems,which threatened agricultural ecological security and sustainable development.It has become an urgent need for the sustainable development of agricultural and ecological environment construction in China to moderately reducing the amount of nitrogen fertilizer input and develop new fertilizers to reduce nitrogen losses,improve nitrogen use efficiency.To clarify the effect and mechanism of yield increasing for applying new type urea in winter wheat and summer maize can provide technical support for reducing nitrogen fertilizer and increasing efficiency.Seven field experiments were carried out in Yuanyang Science and Education Park of Henan Agricultural University from 2016 to 2018,including the loss-control urea reduction and combined application of common urea in winter wheat and summer maize rotation,new type urea application in winter wheat and summer maize,different content of control release and humic acid additives urea application in winter wheat,different content control release and energy-gathered network additives urea application in summer maize.The yield,photosynthetic physiological characteristics,nutrient uptake and accumulation,soil nutrient and nitrogen use efficiency of winter wheat and summer maize were tested.The aim of this study was revealed the response mechanism of crops to reducing nitrogen in winter wheat and summer maize rotation system,to determine the appropriate amount of loss-control urea,the appropriate ratio of loss-control urea and common urea,effect of new type urea,suitable dosage of different urea additives.In order to provide the technical basis for the development and application of new type urea and the realization of nitrogen fertilizer reduction and efficiency enhancement of winter wheat and summer maize.The main research results are as follows:1.The application of 6%Loss-control additive urea in winter wheat and summer maize,3%humic acid additive urea in winter wheat and 1%energy-gathered network additive urea in summer maize could increase crop yield and yield factors,promote dry matter weight and nutrient accumulation above ground,and improve NUE and NAE.Compared with common urea,the yield of winter wheat with 6%Loss-control additive urea and 3‰ humic acid additive urea increased by 10.73%and 11.58%,NUE increased significantly by 10.73 and 11.21 percentage points,respectively.Compared with common urea,the yield of summer maize with 6%Loss-control additive urea and 1%energy-gathered network additive urea was increased significantly by 15.84%and 11.07%,NUE increased significantly by 12.54 and 11.44 percentage points,respectively.The application of 6%Loss-control additive urea and 3‰ humic acid additive urea in winter wheat production,6%Loss-control additive urea and 1%energy-gathered network additive urea in summer maize production were better.2.Compared with common urea,the yield of winter wheat with loss-control urea,loss-control urea one-time application and humic acid urea increased by 17.03%,9.73%and 13.33%,the NUE increased by 15.56,15.98 and 13.27 percentage points,and NAE increased by 6.40,3.66 and 5.01 kg.kg-1,respectively.Compared with common urea,the yield of summer maize with loss-control urea,loss-control urea twice-time application and energy-gathered network urea increased by 12.64%,11.32%and 10.82%respectively,the NUE increased by 15.20,15.98 and 9.60 percentage points,and the NAE increased by 4.79,4.28 and 4.10 kg-kg-1,respectively.In winter wheat production,it is recommended to apply loss-control urea or humic acid urea;in summer maize production,it is recommended to apply loss-control urea or energy-gathered network urea.3.The application of loss-control urea could effectively increase SPAD value and nitrate reductase activity in winter wheat and summer maize leaves,improve photosynthetic characteristics,increase biomass and nitrogen accumulation,and thus increase yield.The effects of loss-controll urea and 70%loss-control urea with 30%common urea were better.Compared with common urea,the annual yield of loss-controll urea and 70%loss-control urea with 30%common urea increased by 10.95%and 11.82%,respectively,and loss-control urea reduction of 10%did not reduce production.The application of loss-control urea improved the nitrogen use efficiency of winter wheat and summer maize in the first anniversary.The effects of loss-control urea constant and 70%loss-control urea with 30%common urea were better.The NAE was significantly increased by 4.11 and 4.26 kg·kg-1 compared with common urea,the NCR was significantly increased by 8.35%and 8.62%,and NUE was significantly increased by 6.92 and 12.47 percentage points,respectively.The loss-control urea reduction of 10%increased the NUE of winter wheat and summer maize in the first anniversary compared with common urea.The application of loss-control urea can effectively improve the soil available nutrient content compared with common urea,and the effects of loss-control urea and 70%loss-control urea with 30%common urea were better.In the production of winter wheat and summer maize,it is recommended to reduce the amount of loss-control urea by 10%(N 189 kg·hm-2)or to combine loss-control urea(N 147 kg·hm-2)with common urea(N 63 kg·hm-2).