Effects Of Drip Fertigation On Summer Maize In North China

The experiment was carried out to study the fertilizer effects of different fertilizer application rates and fertigation way on summer maize under sandy soil conditions in North China,in order to provide a theoretical basis for high-efficiency drip fertigation of summer maize and promote the technology of water and fertilizer integration.Maize variety“Zhengdan 958”was used as materials in the two-year field experiment.The field plot experiment was carried out to study the fertilizer effects of different nitrogen,phosphorus and potassium fertilizer application rates on summer maize and showed drip fertigation could obtain higher nitrogen,phosphorus and potassium fertilizer use efficiency.The large-area field experiment was carried out to study the ammonia volatilization in sandy soil of drip fertigation and the fertilizer effects of different fertigation way and fertilization amount on summer maize.The main conclusions were as follows:1.The yield of summer maize under the conditions of sandy soil field in North China showed a parabolic linear change with the rates of nitrogen and phosphorus fertilizer.The crop yield was the highest when the nitrogen application was 180 kg·hm^-22 and the phosphorus application was 90 kg·hm^-2.When the nitrogen and phosphorus fertilizer application exceeded the maximum yield fertilization amount,the crop yield decreased with the increase of nitrogen and phosphorus application,but the difference of nitrogen fertilizer treatment was not significant.However,when the application rate of phosphate fertilizer exceeded 90 kg·hm^-2,the yield of crop decreased significantly with the increase of phosphorus application?P<0.05?.In this treatment,the yield of summer maize increased with the amount of potassium applied.2.Different fertilization treatments had little effect on the dry matter accumulation of summer maize in the early growth stage.The dry matter accumulation showed the same parabolic linear change along with the increase of nitrogen application rate and phosphorus application rate in the filling period and harvesting period.When the nitrogen application rate reached 180 kg·hm^-22 and phosphorus application rate reached 90 kg·hm^-2,the dry matter accumulation of summer maize could reach the maximum value,and the change trend was nearly the same as the crop yield,while the dry matter accumulation of summer maize increased with the increase of potassium application.3.The use efficiencies of nitrogen,phosphorus and potassium fertilizers were 33.39%-58.44%,14.15%-28.88%and 54.70%-65.75%,respectively.The nitrogen,phosphorus and potassium fertilizer average use efficiencies were 51.21%,28.88%and 65.75%,respectively,when the yield of summer maize was the highest.The average agronomic efficiency of nitrogen,phosphorus and potassium fertilizers were 8.08,11.41 and 8.83 kg·kg^-1,respectively,under the highest yield conditions.At this point,the average partial factor productivity of nitrogen,phosphorus and potassium fertilizers were59.88,119.75 and 100.65 kg·kg^-1,respectively.4.The results of ammonia volatilization monitoring showed that the ammonia volatilization rate reached the maximum on the first day after fertilization at the small bell period.The ammonia volatilization rate gradually decreased from the second day after fertilization,and then showed a stable state with small fluctuations.Fertigation way A2?one drip irrigation belt with two rows of maize?decreased by 20.58%compared with A1?one drip irrigation belt with one row of maize?,and fertilization amount B2(N 139.5 kg·hm^-2?P₂O₅ 76.5 kg·hm^-2?K₂O 76.5 kg·hm^-2)decreased by 22.80%compared with B1(N 180 kg·hm^-2?P₂O₅ 90 kg·hm^-2?K₂O 90 kg·hm^-2)of the maximal ammonia volatilization rate.The accumulation of ammonia volatilization increased steadily of each treatment,and the ammonia accumulation of A1B1 reached the maximum value in the treatment and the average was0.986 kg·hm^-2.Compared with A1B1,the ammonia volatilization accumulation of A1B2,A2B1 and A2B2 decreased by 20.54%,15.04%and 32.81%,respectively.5.The effects of fertigation way and fertilization amount on yield were significant?P<0.05?.The yield of fertigation way was higher in A2,and the average yield increased by 10.21%compared with A1;the fertilization amount on yield of B1 was higher,and B2 has an average yield reduction of 9.82%compared with B1.The interaction between fertigation way and fertilization amount did not reach a significant level.Compared with A1B2,A1B1,A2B1 and A2B2 increased yield by 10.73%,22.17%and10.03%,respectively.One drip irrigation belt with two rows of maize increased the yield by increasing the ear diameter,grain per ear and 100 grain weight,while B1 was more efficient than B2 by increasing the grain per ear of summer maize.