Effects Of Nitrogen Rate And Ratio Of Base And Topdressing Fertilizer On Nitrogen Metabolism After Anthesis,Yield And Soil Nitrate Accumulation Of High-yielding Wheat In North Henan

This study was concerned about the effect of nitrogen fertilizer on the characteristic of nitrogen metabolism and yield after anthesis of wheat,and with the ultimate goal of achieving high-yield,efficient and safetly in production of wheat under the high soil fertility.To study the effect of five N application leaves(0,150,200,250 and 300kg/hm~2)and three Nitrogen fertilizer applied ratios(3:7,5:5,6:4)on groups quality,GS activity,free amino acid content,yield and protein content in the flag leaf and kernel,and NO3-N content in different soil layers from 0 to 100 cm were investigated with aikang-58 as tested material under field condition.As wheat were growing,tiller number were growing,and reached the most at jointing stage。Under the same Nitrogen fertilizer applied ratio,the rate of fertile tillers was increasing while nitrogen was increasing between 150-250 kg N/hm~2,the rate of fertile tillers of the most N application leave 300 kg N/hm~2 was lower than that of the N application leave(250kg N/hm~2),the rate of fertile tillers decreased while the nitrogen was too high.Under the same N application leave,the difference of the treat of 3:7,5:5 and 6:4 is not significant.Under the same N application leave,the Nitrogen fertilizer applied ratio of 5:5 had the most dry matter accumulation.The difference of the treat of 3:7 and 6:4 is not significant.Under the same Nitrogen fertilizer applied ratio the dry matter accumulation was increased with the increasing of N application leave.The difference of the treat of N application leave(200,250 and300 kg N/hm~2)is not significant.At over-wintering stage,LAI had the highest leave at the same Nitrogen fertilizer applied ratio.AT jointing stage,under the same N application leave,LAI had highest leave under the Nitrogen fertilizer applied ratio of 5:5;at heading stage,under the same N application leave,LAI had highest leave under the Nitrogen fertilizer applied ratio of 3:7.The GS activity of flag leaf of all treatments with different source of nitrogen fertilizer had a trend of “down-up-down”.Under the same Nitrogen fertilizer applied ratio,the GS activity had the highest leave under the N application leave(250 kg/hm~2),and the GS activity reduced from 250 kg N/hm~2 to 300 kg N/hm~2.Under the same N application leave,GS activity in flag leaves are the base when the recovery ratio of 3:7 at a high level,but with two dressing not significantly different than the conditions.Glutamine synthetase activity in grains first increased and then decreased.Recover more than the same base level of GS activity in the grain after flowering period were 250 kg N/hm~2 highest when the nitrogen rate;nitrogen in the same conditions,the grain GS activity after flowering,the ratio of 3:7 are Dressing When at a high level,but the dressing ratio 5:5 conditions was not significant.Flag leaf of each treatment with the free amino acid content of the filling process,showing a first increased and then decreased.N0 no fertilization treatment and compared to all fertilization treatments can significantly improve the content of free amino acids in flag leaves.The same base level of recovery than after flowering,flag leaf free amino acid content increased with the nitrogen,nitrogen did not change significantly after the capacity of 250 kg/hm~2.Free amino acid content of seeds showed a decline with advancing stages of the trend.Various periods after flowering,the same amount of nitrogen under the conditions of free amino acids in the flower seeds after 7 days under the conditions of dressing ratio of 3:7 for the highest;than the level in the same dressing,7 days after flowering,14 days after flowering 21 days of free amino acids in grain nitrogen increased with the increase in the amount of 250 and 300 kg/hm~2 under nitrogen was not significant.28 days after flowering,the seed free amino nitrogen treatments were not significant.The same base level of recovery than in the 0 ~ 200kg/hm~2 the nitrogen range,with increased nitrogen,grain yield increased significantly to deal with the highest yield 5:5,200 and 250 kg/hm~2 yield of nitrogen treatment Difference was not significant,300 kg/hm~2 of nitrogen treatment was significantly lower than both the 200 and 250 kg/hm~2 treatment.Under the same nitrogen,different dressing than the difference between the grain yield was not significant.In Spring Wheat,0-20 cm soil layer in all treatments,between the nitrate content in 7.58-21.68mg/kg,the farther down the nitrate content of less;300 kg/hm~2 layers of soil nitrogen treatment Nitrate were significantly higher than the N150 and the N200 treatment,high nitrogen treatment N250 and N300 in the 0-20 cm,60-80 cm soil nitrate content significantly different,other layers are not significantly different.Force conditions in North Highlands,low resistance to the base 58 by 5:5 ratio to recover the amount under 200kg/hm~2 N,N both maximize efficiency and reduce soil nitrate accumulation,but also to maximize the grain Yield;optimal nitrogen application model in the region.For the production of wheat grain quality objectives may be appropriate to increase the application rate,but not higher than 250kg/hm~2.