Effect Of Green Manure Returning To The Field On Growth And Nitrogen Utilization Of Corn

In our country,the middle-and-low-yielding fields soil accounts for about two-thirds of arable land,especially as a major corn producing areas of southwest hilly dry slope land with shallow and barren soil,so the rational application of organic fertilizer?especially Legume Green Manure?is an important way to fertilize soil and promote sustainable corn production.Under the condition of pot experiment,the Leguminous Green Manure Vicia Villosa was selected,setting the experiment on Spring?Summer?Maize with different nitrogen application and Green Manure covering the fields?N0,N150,N150+half the amount of Green Manure,N150+full amount of Green Manure?and the test about different Green Manure overturned in Spring Maize?N0,N150+half the amount of Green Manure overturned,N150+full amount of Green Manure overturned?,having studied the effect of the method and the amount of land returned by Leguminous Green Manure on the maize's growth,dry matter accumulation,yield,nitrogen absorption and transport,nitrogen use and partial physicochemical properties of soil,using the ¹⁵N labeled isotope technology to discuss the effect of Leguminous Green Manure covering the fields on the absorption of soil nitrogen by maize and the effect of overturning Leguminous Green Manure nitrogen on maize in season.The main results are as follows:?1?Leguminous Green Manure?covering and overturning?has a certain promoting effect on maize growth.The dry matter accumulation and grain yield during the main reproductive period of maize were significantly or obviously increased by the Green Manure treatment?covering and overturning?.However,there was no significant effect on the agronomic characters,dry matter and yield of maize in different Green Manure?covering and overturning?.?2?Leguminous Green Manure returning to the field has important influence on nitrogen absorption and utilization of maize.Green Manure?covering and overturning?can significantly improve the nitrogen absorption of maize organs and plants.Compared with N150,the nitrogen translocation and translocation rate of the stalks of the Green Manure covered?N150GF1,N150GF2?were significantly improved.The amount of Green Manure covered no significant effect on nitrogen translocation and translocation rate of maize.However,the amount of Green Manure overturned significantly affected the nitrogen translocation and translocation rate of maize.Compared with N150,Green Manure covering the field improved the agronomy utilization ratio of nitrogen fertilizer,the partial productivity of nitrogen fertilizer,the apparent utilization rate of nitrogen fertilizer,the contribution rate of nitrogen fertilizer and the nitrogen harvest index of maize.The amount of Green Manure coverage did not significantly affect the nitrogen utilization ratio of maize.The amount of Green Manure overturned had an important effect on the nitrogen utilization ratio of maize.The nitrogen utilization rate of N150GM2?full amount of Green Manure overturned?was significantly higher than that of N150GM1?half the amount of Green Manure overturned?.?3?Fertilization can improve ¹⁵N absorption of upper plant of corn field and nitrogen recovery efficiency of soil ¹⁵N.Compared with N150,there was no significant effect on¹⁵N absorption of upper plant of corn field and nitrogen recovery efficiency of soil ¹⁵N by Green Manure covering the fields.The amount of Green Manure mulching also affected maize uptake of soil ¹⁵N.?4?The amount of Green Manure over the field has important influence on the absorption and utilization of ¹⁵N nitrogen in maize growing season.The ¹⁵N uptake at the top of the plant by N150GM2?full amount of Green Manure overturned?was significantly higher than that of N150GM1?half the amount of Green Manure overturned?but the recovery rate of ¹⁵N nitrogen was reduced.Compared with N150GM1?half the amount of Green Manure overturned?,the proportion of grain ¹⁵N of N150GM2?full amount of Green Manure overturned?was significantly increased but the stem and leaf decreased obviously.?5?The Leguminous Green Manure covering the field or overturned was beneficial to improve the content of alkali hydrolyzable nitrogen and organic matter in the top layer of soil in maize growing season.There was no significant effect on the soil pH,alkali hydrolyzable nitrogen and organic matter in the top layer of soil by different Green Manure?covering and overturning?.