Research On Nutrients Management Of High-Yield In Winter Wheat/Summer Maize Rotation

With the continuous growth of the population and incessant shrinkage of the cultivated land, the problem of grain became one of the urgent problems that enjoy worldwide attention, therefore, increasing the per unit area yield of wheat and maize is the only solution for realizing the grain safety in our country. As the chief food crops in our country, the wheat and maize play an important role in ensuring food safety in our country and improving the standard of living of people. Winter wheat/summer maize rotation is the most important crop growing system in Guanzhong of Shaanxi Province,the Guanzhong district is major grain producing area. Fertilizer increasing crop yield is out of question, but in recent years, crop yield was not increasing with amount of fertilizer application increased, at the same time, apparent N fertilizer recovery and production output decreased. In Guanzhong, over-use N fertilizer was very popular, but P and K fertilizer was not concerned very much, what's more, farmers were used to apply fertilizer by their own ways. Over-use N fertilizer may not only cause economic losses, but produce many environmental problems. The field experiment was carried out in Guanzhong district, to study the impact of different fertilization model,different fertilization level,different cultivation pattern on the yield,apparent N recovery and N,P,K absorption of winter wheat/summer maize. The objective of this experiment was to understand and find the technical system of water,fertilizer,variety,density and so on, as well as the rules of nutrients uptake and accumulation in high-yield of crops, and to give a scientific suggestion for the grain safety,scientific fertilization and optimal management of nutrients resource. The main results were showed as follows:1. Effect of N fertilizer postpone on the yield, and N absorption of winter wheatN fertilizer postpone is a technology that adapted some base fertilizer as topdressing. Two field experiments were carried out to study the effect of N fertilizer postpone on the yield, apparent N recovery and N absorption of winter wheat. The objective of this experiment was to find the rule of N absorption and transformation, and to give a scientific suggestion for the high-yield and N application. The results showed that N fertilizer postpone can increase grain yield, number of spike and apparent N recovery of winter wheat, the treatment N4 (50% basal fertilizer, 50% application in erecting stage) is the highest of all, the yield of two field experiments reached 3857kg/ha and 8240 kg/ha, increase yield 25.8% and 17.3%, spike 6.0% and 18.1%, apparent N recovery 111.8% and 107.4% respectively. N absorption and accumulation of winter wheat are mostly from regreening to filling, so under the condition that insured basal fertilizer, application N fertilizer after regreening is very important. In this experiment, the recommendatory N fertilizer postpone pattern is 50% basal fertilizer, 50% application after regreening.2. Effect of N, P, K balanced fertilization on the yield and nutrients absorption, accumulation of summer maizeAt present,the fertilization of summer maize has so many disadvantages, a field experiment was carried out to study the effect of different fertilization models on the yield, apparent N recovery, nutrients absorption and accumulation of summer maize. The objective of this experiment was to find the rule of nutrients absorption and transformation, and to give a scientific suggestion for the high-yield and fertilization. This field experiments were carried out in Dian Beiwan village Fufeng county shaanxi province, and has 6 treatments NPK, NP, NK, PK, FP, CK. The results showed that balanced fertilization (NPK) can increase grain yield significantly, the yield reached 6426 kg/ha, improve 13.2%, 12.9%, 19.3%, 12.0%, 22.9% respectively compared with PK, NK, NP, FP, CK. The curve of biomass accumulation is the same as the curve of nutrients accumulation, assume the shape of"S", the number order of nutrient accumulation is N > K> P, the absorption and accumulation of biomass and nutrients are mostly after the stage of regreening. So fertilization after regreening is very important.3. Effect of N, P, K balanced fertilization on the yield and nutrients absorption, accumulation of winter wheatAt present,the fertilization of winter wheat has so many disadvantages, a field experiment was carried out to study the effect of different fertilization models on the yield, nutrients absorption and accumulation of winter wheat. The objective of this experiment was to find the rule of nutrients absorption and transformation, and to give a scientific suggestion for the high-yield and fertilization. This field experiments were carried out in Dian Beiwan village Fufeng county shaanxi province, and has 6 treatments NPK, NP, NK, PK, FP, CK. The results showed that balanced fertilization (NPK) can increase grain yield significantly, the yield reached 7926 kg/ha, increase yield 2059 Kg/ha and improve 35.1% compared with CK. The curve of biomass accumulation is the same as the curve of nutrients accumulation, assume the shape of"S", the number order of nutrient accumulation is N > K> P, the absorption and accumulation of biomass and nutrients are mostly after the stage of regreening. So fertilization after regreening is very important. 4. Research on the technical system of cultivation management on high-yield summer maizeIn order to explore the maximum production potential of Guanzhong district, study the technical measures and mode of high-yield, this field experiments were carried out to try. This experiment has 7 treatments according to different target yield (15000 kg/ha and 12750 kg/ha), different cultivation pattern (wide narrow row and equi-line), different fertilization model (K application and no K application ). To attribute to outside causes such as climate and illumination, the production potential can not be drawn out, so the yield failed to attain an intended goal The results showed that target yield 12750 kg/ha, wide narrow row, wide line 70 cm, narrow line 50 cm, K application can increase grain yield and agronomic characters significantly, the yield reached 8727 kg/ha, improve 29.9% compared with CK. The biomass was increased with summer maize growing stage, the curve of biomass accumulation assumes the shape of"S".