Research On Effect Of Nitrogen Reduction And Bio-organic Fertilizer Application In Saline-alkaline Cornfield On Growth Promoting Fertility And Synergism

The growth and development of crops in Xinjiang is restricted by the salinization of soil inordinately,the scientific measures to fertilizer reduction and bio-organic fertilizer application are of great significance on green and efficient use of saline alkali soil and the improvement of crop yield.To ascertain the effect of nitrogen reduction and bio-organic fertilizer application in saline-alkaline cornfield on growth promoting,fertility and synergism,Xindong No.55 is selected as the research object in this paper.Through the field trial,4 treatments on nitrogen reduction and bio-organic fertilizer application are established,N1M1（nitrogen fertilizer reduction by 10%+1,125 kg/hm²bio-organic fertilizer）,N1M2（nitrogen fertilizer reduction by 10%+2,250 kg/hm²bio-organic fertilizer）,N2M1（nitrogen fertilizer reduction by 20%+1,125kg/hm²bio-organic fertilizer）and N2M2（nitrogen fertilizer reduction by 20%+2,250 kg/hm²bio-organic fertilizer）,and the treatment with no fertilization（CK）and with conventional fertilization（CF）are used as the control groups,so as to research the effect of nitrogen reduction and bio-organic fertilizer application on growth promoting,soil fertilization and increasing production of winter wheat in saline-alkaline cornfield.The main research results are as follows:（1）The growth characteristics of winter wheat in the saline-alkali land,such as plant height,SPAD,leaf area index（LAI）,dry matter accumulation of various organs in aboveground part（leaf,stem+leaf sheath and spike）during the whole stage of growth and development,are improved by the nitrogen reduction and bio-organic fertilizer application.The dry matter partitioning and transfer characteristic of winter wheat are improved,and the dry weight ratio of leaf,spike and grain,transfer amount of pre-anthesis assimilates,transfer efficiency and grain contribution rate are increased.The nutrient absorption of winter wheat is promoted,and the nutrient content and accumulation of nitrogen phosphorus and potassium in various organs（leaf,stem+leaf sheath,spike,grain and glume and spike-stalk）of the winter wheat during the whole stage of growth and development are increased by 2.31%～18.93%,6.02%～27.77%and 3.03%～15.73%respectively as compared with that of plant treatment with conventional fertilization（CF）;Stem of winter wheat during the middle and later periods+dry matter accumulation and proportion of leaf sheath are reduced.（2）The photosynthetic traits of winter wheat in the saline-alkali land is improved by the nitrogen reduction and bio-organic fertilizer application,SPAD value of winter wheat during the whole stage of growth and development is increased,and the leaf SPAD value of winter wheat during the later period is increased,the net photosynthetic rate,stomatal conductance and transpiration rate of boot leaf of winter wheat during the pustulation period are improved,with a manifestation for diurnal variation of N1M2>N2M2>N1M1>N2M1>CF>CK,which decreases the intercellular CO₂concentration and the effect of"photosynthetic noon break"phenomenon on the photosynthesis.（3）The soil nutrition contents in surface soil（0～20 cm）,such as organic matter（C）,total nitrogen（N）,total phosphorus（P）,total potassium（K）,alkaline hydrolysis nitrogen（JN）,rapidly available phosphorus（SP）,rapidly available potassium（SK）;and the number of culturable bacteria（XJ）,actinomycetes（FXJ）and microorganism（Z）of winter wheat in rhizosphere soil during the mature period are increased by the nitrogen reduction and bio-organic fertilizer application,while the number of fungus of winter wheat in rhizosphere soil during the mature period is reduced.And soil p H and conductivity of winter wheat in the saline-alkali land during the later period is reduced by 2.47%～3.93%and 8.56%～9.63%respectively as compared with the conventional fertilization（CF）treatment.The correlation among the surface soil saline-alkaline index（EC and p H）,soil nutrient index（C,N,P,K,JN,SP,SK）and soil biological index（XJ,ZJ,FXJ,Z）during the wheat mature period is between 0.70～1.00,and there is a extremely significant negative correlation among soil saline-alkaline index,soil nutrition content and the number of beneficial microorganism（XJ,FXJ）（p<0.01）.（4）The yield composition of winter wheat in the saline-alkali land is improved by the nitrogen reduction and bio-organic fertilizer application,and the winter wheat yield in the saline-alkali land is increased by 1.71%～16.00%as compared with the yield of conventional fertilization（CK）treatment.Yield benefit and net benefit increased by RMB 293～2714 yuan/hm²and 63～589 yuan/hm²respectively as compared with the conventional fertilization（CF）treatment.The grain quality of winter wheat,coarse protein content,starch content,wet gluten content and sedimentation value are increased by 0.18%～4.92%,4.83%～7.33%,7.40%～10.30%,13.38%～18.91%respectively as compared with the conventional fertilization（CK）treatment.（5）The synthesis scores of simple-targeted fertilization effects（yield and its economic effectiveness,grain quality,soil physical and chemical properties,soil biological levels）on various treatments are manifested as follows:N1M2（nitrogen fertilizer reduction by 10%+2,250 kg/hm²bio-organic fertilizer）fertilization treatment reigns supremely The synthesis scores of multi-targeted fertilization effects on treatment of nitrogen reduction and bio-organic fertilizer application are higher than those in the CK and CF treatments,which are manifested as N1M2>N2M2>N1M1>N2M1>CF>CK.In conclusion:The growth and development of winter wheat in the saline-alkali land can be promoted significantly with the 10%reduction of nitrogen fertilizer and application of 2,250 kg/hm²bio-organic fertilizer,the soil fertility can be improved,the effects of growth promoting,fertility and increasing production can be achieved,which can be used as a reference for improvement and utilization of saline-alkali cropland.