Effect Of Straw Returned To The Field With Chemical Fertilizer On The Growth And Grain Yield Of Summer Maize

With high quality and efficiency variety promotion and multiple crop index increased, the soil fertility should be improved. Crops straw contains large amounts of organic matter, and also contains nitrogen, phosphorus and potassium required for crop growth. Therefore, the straw has become one of the most important agricultural materials which can be used to improve the content of organic matter in the soil, soil fertility, soil structure and increase crop yield. The straw returning rate of north Anhui is low because most of them are burned which not only pollute the environment but also waste straw resources.In order to researched the effects of total crushed straw combined with chemical fertilizer on the growth of the organism and physiological and ecological response for maize, a two consecutive years field experiment was conducted with Zhengdan958 which widely cultivated in north China so as to provide theoretical basis for high-yield cultivation of the straw returing. The main results are as follows:1. straw returning combined with chemical fertilizer application can significantly improved the soil moisture of 0-20 cm layer, reduced soil moisture evaporation, and improved the water retention of soil, thereby improving soil moisture content for maize, the water requirement during growth and development. Continuous double cropping straw returning combined with mineral fertilizer significantly reduced the soil bulk density during different growth period.2. straw returning in two seasons combined with chemical fertilizer application significantly increased maize leaf area index, leaf chlorophyll content and the with dry matter accumulation of nitrogen and groups of different organ and leaf layer, which conducived to improving the photosynthetic chractristic and increase grain filling degree, providing the material basis for high yield of maize.3. wheat and maize straw returning the combined with chemical fertilizer application increased average grain filling rate and extended maize grain filling stage. It’s the main reason why maize grain weight increased.4. straw returning was helpful to improve the yield of summer maize. Wheat andmaize straw returning two seasons combined with fertilizer application production is better than that of single season straw returning and chemical fertilizer application which the double cropping of wheat and maize straw and chemical fertilizer treatment gained the highest yield. At the same time straw returning and chemical fertilizer application improved the seed characteristics of ears which lay the foundation of high yield for summer maize. Moreover straw returning and chemical fertilizer application improved the content of maize oil, increased grain protein content and starch content significantly, which is beneficial to improving the grain quality of maize.