The Effect Of Urea Application Combined With Slow Release Fertilizer On Spring Corn In Weibei Dryland

Maize(Zea mays L.)is one of major grain crops in China.To satisfy the requirement of fertilizer required rhythm,the most common model on fertilizer application is topdressing quick acting nitrogen fertilizer on basal fertilizer more than twice.The pattern namely increased labor intensity and economic costs,though it may improve yields.Slow release fertilizer(SRFs)can use its regulative mechanism to release nutrients slowly.Large scale using with SRFs is limited by its high cost.This experiment was conducted to study the influence of soil nitrogen and yield in maize growth period with different N level: 100%,80%,and 60%.Those different combined applications were set for further study to reduce production cost and increase the utilization ratio of fertilizers.The main conclusions in this paper are as follows:1.When the proportion of urea and SRFs was3:7,Maize got the maximum yield,reflected in hundred-grain weight(HGW).The same would be true for water consumption.With the same proportion,the ammonia nitrogen content was minimum in 0 to 200 cntimeter andthe nitrate nitrogen content lower in 140 to 200 centimeter after harvest.2.With decreased-nitrogen cultivation,combined application of urea and SRFs increased yield and HGW more than split application of urea.With 80 percent of nitrogen and the proportion of 3:7,Maize got the maximum yield,reflected in HGW.The same would be true for water consumption.With 80 percent of nitrogen after harvest,the ammonia nitrogen content in soil was lower in 0 to 120 cntimeter and higher in 120 to 200 centimeter.With the proportion of 3:7,the ammonia nitrogen content was lower in 0 to 100 centimeter and higher in 100 to 200 centimeter in all different N levels.The nitrate nitrogen content in soil was lower with 80 percent of nitrogen,and no significant difference in 100 to 200 centimiter.With all kinds of N levels,the nitrate nitrogen content was nearly,but higher in 100 to 200 centimiter with the proportion of 3:7.