The Impact Of The Combined N And Zn Fertilizer Treatment On The Improvement Of Wheat Production And N Uptake

In China, wheat is one of the three most important food crops. With the increasing of the population and natural disasters such as flood and drought, decreasing of arable land and increasing natural disasters such as flood and drought, it is of vital importance to increase and stabilize wheat production to insure food security in China. N, Zn and Mg are three indispensable nutrient elements in the growth of wheat. Of which N is one of the important factors affect the production and quality of wheat, Mg plays an important role in photosynthesis and many other physiological metabolism processes. Zn is the component and activator many enzymes in plant which participates in the metabolism of nitrogen and the synthesis of auxin. This study takes wheat which has grown for22weeks as material, discusses the impact of the combined N and Zn fertilizer treatment on the improvement of wheat production and N uptake and to provide the scientific basis for reasonable fertilization and the improvement of wheat production. The results showed that:1. The combined N and Zn fertilizer treatment significantly increased grain yield, but EDTA application or with Zn fertilization had no marked effect on yield. N and Zn fertilized alone obtained the highest grain yield (increase rate was7.6-11.1%), but the combined N and Mg fertilization showed no significant interaction effect.2. In the N and Zn fertilizer experiment, N fertilization increased wheat shoot dry weight22.51%,13.27%,14.25%,12.54%and9.45%, respectively for over-wintering stage, erecting, jointing stage, booting stage and maturity, relative to unfertilized treatment. The difference was significant in the jointing stage. The shoot dry weight was averagely9126kg/hm2in the Zn fertilized treatment, which is4.48%,4.97%and10.26%higher than combined fertilization of Zn and EDTA, control and EDTA alone, suggesting that Zn fertilization can increase shoot dry weight. The dry weight of stem, leaf, glume and grain was largest in the combined application of N and Zn. The combined N and Mg fertilizer treatment has no significant increase effect on the shoot dry weight in different growth stages.3. In the wintering and standing period of wheat, the N mass fraction was relatively higher, but it was gradually reduced in the jointing stage, and the N concentration was in a decreasing order of leaf, spike, sheath, stem, while grain contained higher N in the mature period. During the same growth period, there were no significant difference of N mass fraction in the no N fertilizer treatment, N fertilizer alone treatment, Zn fertilizer alone treatment, and the combined N and Zn fertilizer treatment. During the booting stage, the Combined N and Mg fertilization showed a slightly higher N concentration in the booting stage in leaf, sheath, and spike. Mg application has no significant effect on the N accumulation in the earlier growth stage, but N uptake was improved by10~20%in the mature period.4. The combined application of N and Mg fertilizer averagely increased wheat N uptake0.64kg/kg; the partial productivity of N was20.5kg/kg, and the N fertilizer utilization was20.8%. The partial productivity of the combined application of N and MgSO4was higher than MgCl2, but the N uptake efficiency was higher in the combined application of N and MgCl2than in the MgSO4, but the difference was1%. There were no significant difference of N mass fraction in the no N fertilizer treatment, N fertilizer alone treatment, Zn fertilizer alone treatment, and the combined N and Zn fertilizer treatment.5. The N uptake efficiency of the combined application of N and Zn was averagely0.63kg/kg, and its N uptake efficiency, N partial productivity, N fertilizer utilization were higher than other treatments. N utilization was3.9%higher in the Zn fertilization treatment than in the Mg fertilization treatment. Zn plus EDTA lowered N utilization1.8%than Zn fertilization.