Study On Water And Nitrogen Effects Of Different Fertilization Methods In The Cotton Region Of South Xinjiang

Precision agriculture is the development trend of my country’s agriculture.In order to improve water use efficiency and increase cotton production,this article has carried out a study on the water and nitrogen effects of cotton in southern Xinjiang.The experiment adopts the split zone design method.The main zone has different fertilization methods F1（batch input of nitrogen,phosphorus and potassium fertilizer）and F2（one-time input of phosphorus and potassium fertilizer）,and the secondary zone has irrigation quota and nitrogen application rate.There are 3 irrigation treatments(3300m³·hm^-2,3900m3·hm-2,4500m³·hm^-2)and4 nitrogen treatments(150kg·hm^-2,225kg·hm^-2,300kg·hm^-2,375kg·hm^-2)different Water and nitrogen treatment,to study the effects of different water and nitrogen treatments on the growth period,growth traits and yield of cotton in the salinized areas of southern Xinjiang,and establish a water and nitrogen-yield model.Through the model,the advantages and disadvantages of the two fertilization methods are compared,and the suitable water and fertilizer program for the cotton in the area is selected.The main research results are as follows:（1）The method of fertilization and the amount of water and nitrogen have different effects on the growth period of cotton.The fertilization method F2 appeared 3-4 days earlier than the fertilization method F1.Cotton plant height gradually increased with the increase of nitrogen application rate.Under the same nitrogen application level,the degree of influence on plant height was W4500>W3900>W3300.Irrigation amount has a certain effect on cotton stem diameter.The nitrogen application level of the two fertilization methods is the same,and W3300 is less than W3900 and W4500.Irrigation quantity also has a great influence on cotton leaf area.Under the same nitrogen level,W3300<W3900<W4500.It shows that the amount of irrigation water has a greater impact on the growth period of cotton.（2）The shedding rate of cotton buds and bolls is greatly affected by water and nitrogen.Under the treatments of W3300N150 and W4500N375,the drop rate was the largest.Under low water treatment,cotton cannot absorb enough water,causing buds to fall off;under high water treatment,with the application of nitrogen fertilizer,the shedding rate first decreases and then increases,indicating that after cotton absorbs nitrogen fertilizer,excessive nitrogen fertilizer accumulates in the soil,causing The absorptive capacity of cotton decreases,which leads to an increase in the shedding rate.（3）Obtained through the water and nitrogen-yield model,the actual output has a higher degree of fit with the simulated output.Compared with F1,the average yield of F2 is 16.56%higher,the average IWUE is 15.4%higher,and the amount of irrigation and nitrogen input is less.（4）In summary,the experiment considered that the more reasonable fertilization method is F2,and the reasonable water and nitrogen combination is:irrigation amount 3874.8-4191.6 m³·hm^-2,nitrogen application rate 345.525-353.85 kg·hm^-2.Based on field experiments and model analysis,this paper screened out suitable fertilization methods and reasonable water and nitrogen combinations for cotton planting in this area,which is of great significance to improve agricultural water use efficiency,reduce cotton costs,and increase fertilizer utilization.