Effects Of Water And Fertilizer Regulations On The Distribution Of Soil Water And Nitrogen And The Growth Of Waxy Corn Under Full Plastic Plastic Double Ridge And Furrow

In 2021,corn became the largest food crop in China.In order to make the corn plant grow rapidly,the unilateral pursuit of the maximum yield,farmland soil irrigation and fertilizer amount is too much,causing serious harm to the soil environment,is not conducive to the sustainable development of soil.So according to the law of water and fertilizer in crops,rational fertilization on crop root zone soil management,optimize the management system of water,the water of water and fertilizer,fertilizer promoting ",give full play to the role of the irrigation water and the fertilizer,improve water use efficiency and the final production,to achieve the ultimate goal of high quality and high yield,to maintain the sustainable development of soil at the same time have the very vital significance.This research adopts the whole membrane double ditch seeding planting method,in order to "jin single gene.for 41" waxy maize varieties for experiment,set up two irrigation and fertilization factor,irrigation frequency set two levels:W0 irrigation in the whole stages(seeding time,seedling stage,jointing stage to booting stage stage,jointing stage and booting stage,flowering period)and part W1 changeable irrigation(seeding time,late jointing stage and booting stage);The nitrogen application times were set at three levels:N1(100%of all basal application),N2(30%of basal application+70%of trumpet application stage),and N3(30%of basal application+30%of jointing application+40%of trumpet application stage).A complete combination design was adopted,with a total of 6 treatments,and each treatment was set to be repeated for 4 times.The effects of different water and fertilizer treatments on soil water and nitrogen profile distribution,nitrogen residue,growth status,yield and water and nitrogen use efficiency of waxy corn were analyzed to provide a theoretical basis for the establishment of the optimal irrigation and fertilization management system.The following conclusions are drawn:(1)The water and nitrogen treatments had significant effects on the water and nitrogen distribution in the root zone soil profile of waxy maize.In the horizontal direction of the soil profile,the source point is the center of the diffusion to both sides,and the soil moisture content gradually decreases.In the vertical direction,with the source point as the center,the moisture range of the soil gradually expands,and the degree of water diffusion in the horizontal direction is greater than that in the vertical direction.In the jointing stage,under the same nitrogen application and different irrigation treatments,the relationship between the profile moisture content of 0-40cm soil layer was as follows:W0>W1;The application of topdressing nitrogen fertilizer was more beneficial to the absorption and utilization of soil water by crop roots than that of all basal fertilizers,and the application of topdressing nitrogen fertilizer at trumpet stage and jointage stage was more beneficial to the growth of waxy-corn roots and promoted the absorption and utilization of soil water by roots than that of topdressing nitrogen fertilizer only at trumpet stage.According to the soil NO3-N profile distribution under different water and nitrogen treatments,there were obvious NO3-N-enriched areas at+20cm(source point)in the horizontal direction.The NO3-N-enriched areas under N1,N2 and N3 treatments were 30-95mg/kg,34-62mg/kg and 25-75mg/kg,respectively.N1 treatment was significantly higher than the other two treatments,and the diffusion rate of nitrate in horizontal direction was much higher than that in vertical direction.In the jointing stage,the plant grows faster and the soil needs to provide water and nutrients to meet the needs of crop growth.Nitrogen topdressing under the N3 treatment enables the crop root system to better absorb and use nutrients in the soil at this stage.Moreover,under the irrigation treatment of W1,the nitrate nitrogen in the soil is concentrated in the surface layer,which is more conducive to the absorption and utilization of the root system.(2)Different water and nitrogen treatments had different effects on the nitrate nitrogen residues in the root zone soil of waxy corn.Improper water and fertilizer management system caused nitrate nitrogen to migrate to deep soil,and soil environment was polluted,which was not conducive to the sustainable planting of the soil.After the growth period of waxy corn,under the same irrigation treatment,compared with the soil nitrate nitrogen residue under N1 treatment,the nitrate nitrogen residue in the root zone of waxy corn under N2 and N3 treatment increased by 29.52%-46.49%and 16.37%-16.76%,respectively.Under the same N application treatment,compared with W1,the nitrate nitrogen residue in the root zone soil of waxy maize under W0 treatment increased by 8.5%-22.82%.(3)In the growth period of waxy corn,the promotion effect of different topdressing of nitrogen fertilizer on the growth of waxy corn was greater than that of one basal application of nitrogen fertilizer.Under the condition of this experiment,the relationship between plant height,stem diameter and leaf area index of waxy corn among all nitrogen treatments was as follows:N3>N2>N1,and there were significant differences among all treatments.In flowering period under different nitrogen treatment quality of the dry matter of waxy maize is the size of the relationship is:the N3>N1>N2,topdressing of nitrogen fertilizer is more advantageous to the ground part of the amount of dry matter accumulation,crop and in jointing stage,huge bellbottom period,respectively,than in the big bell stage of topdressing nitrogen topdressing nitrogen fertilizer of waxy maize dry matter accumulation of aerial part better.At the maturity stage,the relationship between the abovine dry matter weight of waxy corn among different treatments was W1N3>W0N3>W0N2>W1N2>W0N1>W1N1,and reached the maximum under W1N3 treatment,which was 15.58t/hm2,and the difference was significant.(4)Under the same irrigation treatment,the relationship of photo synthetic indexes(Pn,Tr,GS,Ci)of leaves under different N treatments were N3>N2>N1.Nitrogen topdressing could significantly improve the photosynthetic capacity of crop leaves in the big flared stage.(5)Under the same irrigation treatment,the relationship between the economic yield of waxy-maize under each nitrogen application treatment was N3>N2>N1,and there was a significant difference among all treatments.In the whole growth period of waxy corn,the economic yield under the treatment of basal application and topdressing of nitrogen fertilizer was much higher than that under the treatment of one-time basal application of nitrogen fertilizer,and different topdressing treatments had different effect on waxy corn yield increase.The yield increase effect of topdressing nitrogen at jointing stage and bell-mouth stage was much higher than that of topdressing nitrogen only at bell-mouth stage.(6)The application of nitrogen fertilizer in different stages was beneficial to the growth of waxy corn,which accelerated the absorption and utilization of soil water by the root system,and improved the water consumption and water use efficiency in the whole growth of waxy corn.Under the same irrigation treatment,WUE increased gradually with the increase of nitrogen topdressing times.Under the same nitrogen application,the water consumption of waxy corn treated with irrigation in whole growth period was greater than that of waxy corn treated with irrigation in part growth period.Under the same irrigation treatment,with the increase of nitrogen topdressing times,the partial productivity of nitrogen fertilizer and the agronomic use efficiency of nitrogen fertilizer both showed an increasing trend.Nitrogen partial productivity and agronomic use efficiency of waxy corn under all water and nitrogen treatments reached the maximum under W1N3 treatment.Under the same irrigation treatment,compared with N1,nitrogen partial productivity under N2 and N3 treatments increased by 4.39%-15.37%and 17.12%-23.89%,respectively,and nitrogen agronomic use efficiency increased by 3-7kg/kg and 9.19-12kg/kg,respectively.The application of nitrogen fertilizer in different times was beneficial to the absorption and utilization of fertilizer by the root system of waxy-corn,and the partial productivity of nitrogen fertilizer and the agro utilization efficiency of nitrogen fertilizer were improved,thus creating favorable conditions for the high yield of crops.To sum up,in the environment of the test area,waxy-corn was planted on whole plastic-film double ridges in furrows,and irrigation was carried out in part of the growth period(seeding period,late jointing stage and booting stage to control soil moisture content of 75-85%of field water capacity).Under the treatment of basal application+topdressing(total N application rate of 384.62kg/hm2)(basal application 30%+topdressing 30%at jointing stage+topdressing 40%at trumpet stage),the growth condition of waxed corn was better,and the yield and water and nitrogen use efficiency were the best.