Effects Of Combined Application Of Nitrogen And Zinc On Zn Nutrition,Grain Yield And Quality Of Wheat(Triticum Aestivum L.)

Wheat(Triticum aestivum L.)is the staple food of people in north China,and is an important source of trace elements such as Zn and other trace elements necessary for human body.Excessive fertilization will cause soil and environmental pollution and waste of resources.Human zinc deficiency is widespread in the world within the scope of the problem,from the staple intake of zinc is the main source of zinc absorption for vegetarian.In order to improve grain zinc content,reduce waste of resources,improve wheat nutritional quality and provide theoretical basis for high quality,high yield and high efficiency wheat cultivation.In this study,Zhoumai 22 was used as materials which is one of the most popular winter wheat cultivars in Huanghuaihai Plain.The accumulation dynamics and distribution of Zn under different nitrogen levels in wheat plant,application of nitrogen fertilizer,Zn nutrition of wheat grain control and solve the zinc deficiency problem was studied,and to provide theoretical basis and effective control measures.The main results are as follows:(1)The effect of Zn on Zn uptake and transport in wheat plants at different nitrogen levels.Zn content in different parts decreased significantly with the decrease of nitrogen application rate.The Zn content of soil,root and stem reached the highest level at jointing stage.The zinc content in soil and root increased significantly under different nitrogen levels,and the highest increases were 371.78% and 77.88%,respectively.And the control of spraying zinc fertilizer significantly increased leaf,stem and glume and grain Zn content of 67.08%,11.04%,-7.03%,21.97%.(2)Effects of Zn on nitrogen content of Wheat under different nitrogen levels.Under the conditions of different nitrogen application rate and zinc application mode,the nitrogen content of soil increased with the decrease of nitrogen application rate,and the nitrogen content of other parts of plant decreased with the decrease of nitrogen application rate.Soil zinc fertilizer + Spraying zinc fertilizer significantly increased the nitrogen content of plant roots and stems,and the nitrogen content of plant leaves and grains increased significantly by spraying zinc fertilizer.(3)The content of nitrogen and zinc in the upper and lower parts of the grains and glumes were significantly different.The nitrogen and zinc contents in the upper and lower parts of the glumes were increased,and the content of nitrogen and zinc in the upper and lower parts of the grains was significantly different with the treatment.(4)The effect of zinc on Grain Yield and quality at different nitrogen levels was reduced by 10.03% and 12.78%,respectively,and reached a significant level.Application of zinc fertilizer increased grain yield,but there was no significant difference.Spraying zinc fertilizer increased the content of crude protein,soluble sugar,amylose,amylopectin,total starch and amylose ratio of wheat grain.In addition,the application of zinc fertilizer and nitrogen fertilizer at the same time could significantly improve the grain quality of wheat compared with that of single application of nitrogen fertilizer or soil application of zinc fertilizer under the condition of nitrogen application.(5)The effect of zinc application at different nitrogen levels on harvest index and utilization ratio of wheat.There was no significant difference in harvest index between nitrogen level and zinc application mode.Zinc harvest index increased significantly with the decrease of nitrogen application rate,but significantly affected the total zinc utilization rate and grain zinc utilization efficiency of plants.Reducing nitrogen fertilizer reduced the total zinc utilization rate and zinc utilization rate of 95.62%,117.38% and 83.35%,131.38% and 131.38%,respectively.Compared with the control,zinc fertilizer application significantly increased the utilization ratio of zinc in grain and total zinc,and the utilization ratio was higher than that in soil and foliar spraying.To sum up,under the condition of conventional nitrogen application(240 N kg?hm-2),spraying zinc fertilizer on the leaves of potential zinc deficient soil can not only reduce soil,environmental pollution and waste of fertilizer resources,but also effectively improve grain zinc use efficiency and quality,and ensure continuous high yield of wheat.