Effects Of Rhamnolipids On The Physical And Chemical Properties Of Salted Cotton Field Soil And Cotton Growth

The excellent surface activity of rhamnolipids can regulate transpiration during cotton foliar spraying operations.At the same time,it can improve the soil environment and promote the absorption of nutrients by plants,and alleviate the harm of salinization to cotton growth and yield.Therefore,the study of rhamnolipids is of great significance to the physical and chemical properties of saline cotton fields and cotton growth,and at the same time provides theoretical and practical support for the popularization and application of rhamnolipids in southern Xinjiang.In this study,spraying rhamnolipid treatment（S,concentration of 300 mg/L）,spraying with transpiration inhibitor treatment（T,concentration of 0.6%）and spraying water treatment as a control（CK）,research spraying Rhamnolipid as a transpiration inhibitor has anti-transpiration effect on cotton leaves;combined with drip irrigation technology,set the rhamnolipid concentration to 300 mg/L,and apply it to low-salt treatment（1000μS/cm,T1）,medium-salt treatment（2000μS/cm,T2）and high-salt treatment（3000μS/cm,T2）.μS/cm,T3)and non-drip treatment,to study the effects of dripping rhamnolipid as a soil conservation agent on soil salinity,ions,cotton growth physiology and yield and quality in cotton fields.Physiology,yield and quality.Draw the following main conclusions:（1）Spraying rhamnolipid has a significant effect on cotton chlorophyll,stalk flow rate and photosynthetic index.Compared with the treatment with water CK,the chlorophyll content,stalk flow rate and photosynthesis of the treatment with rhamnolipid were significantly reduced,and the treatment with rhamnolipid S was significantly higher than that of the treatment with transpiration inhibitor T Treated at T.Among them,chlorophyll S treatment decreased by 8.59%on average compared with CK treatment,and S treatment increased by 12.64%on average compared with T treatment;and the R2 results of linear correlation analysis of fitting showed that the fit degree was higher after spraying rhamnolipid.Spraying rhamnolipids has a significant regulatory effect on cotton transpiration.（2）After dripping with rhamnolipid,each treatment has the best desalination rate of 0-20 cm soil depth.The desalination rate of 1000μS/cm treatment is 37.82%,and the desalination rate of 2000μS/cm treatment is 12.64%.The salt rejection rate of 3000μS/cm treatment was 8.79%.The content of Cl^-,SO₄^2-,K⁺,Na⁺,Ca²⁺,Mg²⁺in the soil has been significantly reduced,and the damage of excessive soil ion content to the growth of cotton is alleviated.Drip application of rhamnolipid has a significant effect on cotton growth,physiology,IWUE,harvest index,yield and quality of cotton under different salt treatments.Cotton leaf area index,stem thickness,plant height and dry matter accumulation are significantly increased;SPAD value in the seedling stage There is no obvious change,and the changes are obvious in the bud stage and the flower and boll stage;during the whole growth period,the photosynthetic parameters in the bud and early flower and boll stages are more obvious after the application of rhamnolipid.Drip application of rhamnolipids can adjust different saline soils.The yield of 1000μS/cm treatment increased by 3.16%,the yield of 2000μS/cm treatment increased by 1.03%,and the yield of 3000μS/cm increased 19.65%.However,the effect on cotton quality was not significant,and the high-salt treatment had the best yield.