Study On The Effect Of The Depth Of Smashing Ridge Tillage And Irrigation Amount On Cotton Growth In Salinized Cotton Field

Object;The efficiency of agricultural water use in southern Xinjiang is low.The research on water-saving irrigation technology and saline-alkali land improvement method is an important way to break through the bottleneck of local agricultural development.Drip irrigation under film has the function of saving water and increasing yield,and regulating soil salinity outside the crop root zone.Smashing ridge tillage has the effect of breaking the soil plow pan to build a loose and deep tillage layer,repairing the soil and desalinating the soil salinity.In this thesis,through the study of the combination mode of the depth of the powder ridge and the amount of irrigation,the best combination mode of different depth of the smashing ridge tillage and the amount of irrigation on the growth and benefit of cotton under the condition of drip irrigation under the film is determined,which provides a theoretical basis for saving water and increasing production and efficiency in saline-alkali cotton fields.Methods;In this experiment,a field experiment was carried out in Tumushuke City,the third division of Xinjiang Production and Construction Corps in 2022.Three smashing ridge tillage depths(F1:20,F2:40,F3:60 cm),three irrigation levels(I1:3600,I2:4500,I3:5400 m~3/ha)and conventional tillage irrigation control treatment(CK)were set.Results;The effects of different combinations of smashing ridge depth and irrigation amount during growth period on soil bulk density,porosity,water content,salt content,cotton plant height,stem diameter,leaf area,cotton root weight density,root length distribution ratio,root activity and yield benefit were investigated.The multi-objective optimization method was used to determine the optimal combination mode of smashing ridge tillage depth and irrigation amount during growth period.The main results are as follows:(1)Compared with CK,the soil bulk density decreased significantly after the treatment of smashing ridge tillage,and the soil bulk density and soil salt content decreased with the increase of irrigation amount and smashing ridge tillage depth.Soil porosity and soil moisture content increased with the increase of smashing ridge tillage depth and irrigation amount,and the effects were as follows:F3>F2>F1>CK,I3>I2>I1>CK.(2)Compared with F2,F1 and CK treatments,the average plant height of F3 increased by 1.38%,14.47%and 29.46%,respectively.In the same growth period,the stem diameter of cotton under different treatments was F3>F2>F1>CK,I3>I2>I1>CK.In the same growth period,when the leaf area reached the maximum,it was F3>F2>F1>CK,I3>I2>I1>CK.(3)In the vertical direction,the root weight density of cotton increased with the increase of the depth of the smashing ridge tillage in each soil layer.The root length distribution ratio of each treatment was concentrated in the 40-60 cm soil layer.The root weight density,root length distribution ratio and root activity of cotton increased with the increase of the depth of the ridge and the amount of irrigation,and the effects were as follows:F3>F2>F1>CK,I3>I2>I1>CK.(4)The maximum boll weight of cotton was F3I3 4.58 g,the highest yield of cotton field was F2I35869.12 kg/ha,the highest economic benefit of cotton field was F1I1(13383.70 RMB/ha),the lowest economic benefit of cotton field was F2I3(13383.70 RMB/ha),and the economic benefit difference was 1.77times.Conclusion;Under the condition of drip irrigation under film,the combination of smashing ridge tillage and irrigation control during growth period can increase soil porosity and soil moisture,reduce soil bulk density and salt,and then affect the growth and gain of cotton.Through the multi-objective method,it was determined that when the depth of the powder ridge was 36.52-48.93 cm and the irrigation amount during the growth period was 4777.35-5116.61 m~3/ha,the root weight density,root length distribution ratio,yield and economic benefit of cotton reached the maximum at the same time,which was the optimal combination mode of deep smashing ridge tillage and irrigation amount during the growth period in the study area.