Effects Of Planting Pattern And Sowing Date On Winter Wheat Growth And Soil Water And Nitrogen Utilization

Winter wheat is the main food crop in arid and semi-arid agricultural areas in northern my country.However,agriculture in this area has been continuously affected by drought and global warming in recent decades.Conventional cultivation methods and sowing dates will result in low winter wheat yield and water and nitrogen use efficiency.The tight operation time during farming has greatly affected the enthusiasm of food crops.In order to solve the problems of water shortage,low water and nitrogen utilization efficiency and tight farming time in this area,it is necessary to conduct research on the current planting system in this area.In this study,the traditional flat cropping planting mode under the normal sowing date was used as a control to study the moisture-preserving planting methods of ditch full film mulching and flat cropping full film mulching and delaying the sowing date on the growth and development of winter wheat,nitrogen absorption,yield and economic efficiency,water and nitrogen utilization The efficiency and the influence of soil water,fertilizer,heat and other environmental conditions,the effects of mulching and rainwater harvesting to preserve moisture in the arid and semi-arid agricultural regions of northern my country are discussed,and combined with path analysis,it is determined that the arid and semi-arid in northern my country Suitable sowing dates and supporting planting patterns for winter wheat in agricultural areas provide a theoretical basis for ensuring the yield of winter wheat in this area and improving water and nitrogen use efficiency.The main research conclusions are as follows:(1)Compared with the normal sowing date,postponing the sowing date(late sowing and latest sowing)will inhibit the growth and tillering of winter wheat before overwintering,which is not conducive to the absorption and utilization of natural precipitation and soil moisture during the whole growth stage of winter wheat.Sowing will also affect the development of ears and significantly reduce the thousand-grain weight;shorten the vegetative growth time,delay the development of the canopy and the progress of senescence,thus improve the photosynthesis from flowering to maturity;increase the soil moisture content of 0-40 cm in the mature stage,Nitrate nitrogen and ammonium nitrogen content,nitrogen utilization efficiency and economic efficiency.(2)Compared with the flat cropping without film mulching,the furrow full mulching and flat cropping mulching can promote the growth and development of winter wheat during the whole growth stage and the tillering before overwintering,and the ear development is better;increase the full growth of winter wheat The water content of the 0-20 cm soil layer,the water consumption of the 0-200 cm soil layer and the soil temperature at 20cm(the temperature increase and decrease in the ridge and furrow full mulching planting mode are faster than the flat cropping full mulching planting mode);significant increase in nitrogen Harvest index,nitrogen use efficiency,economic efficiency and yield.Among them,the ditch full film mulching planting mode has more obvious promotion of the growth and development of winter wheat from booting to maturity than the flat cropping full film mulching planting mode,and has a greater increase in the nitrogen harvest index,nitrogen use efficiency,and economic efficiency of winter wheat,and can reduce delay The unfavorable effects of the sowing date,and the flat cropping and full film mulching planting mode has a more significant promotion effect on the growth and development of winter wheat from the green to booting stage;reducing the deep layer(80-200cm)soil moisture,nitrate nitrogen and ammonium nitrogen content in the mature stage,Which reduces the risk of nutrient loss and groundwater pollution.(3)The path analysis shows that ear length is the most important factor affecting yield.Within the range of the sowing date of this study,the effective accumulated temperature during the growth period of winter wheat has a positive effect on yield.Therefore,under the current climatic conditions,in the arid and semi-arid areas of northern my country,the delay in planting of winter wheat should not exceed 7 days compared with the traditional time.(4)Compared with the traditional flat cropping planting under the local normal sowing period,the yield of winter wheat planted with film mulching in furrows under the latest sowing treatment increased significantly,and the yield of flat cropping with film mulching planting increased slightly,indicating that the furrows were fully mulched Planting and planting with full film mulching can compensate for the yield reduction effect caused by the delay of the sowing date,and to a certain extent solve the problem of the local weather,busy farming and other factors that the winter wheat cannot be planted on time.