Study On Improvement Of Greenhouse Soil By Combination Of Microbial Inoculum And Straw Fertilizer

In order to improve greenhouse soil salinization and sealing problems,screening,identification and structuring mixed bacteria system of a number of strains was isolated from soil,finally,pot experiment was carried out by combination of straw organic fertilizer and microorganism,the main results are as follows:1、Screening of phosphate-solubilizing strains and nitrate nitrogen degradation strainsPhosphate-solubilizing strains and nitrate nitrogen degradation strains were isolated from saline-alkali soil and greenhouses soil samples.Four phosphatesolubilizing strains with strong dissolving phosphorus ability were isolated from 307 phosphate-solubilizing strains.These strains were identified as penicillium funiculosum,penicillium oxalicum,penicillium aculeatum and penicillium oxalicum through the analysis method of morphology and molecular biology.The highest amount of soluble phosphorus was 1064.21μg/mL.Seven nitrate nitrogen degradation strains with strong nitrate nitrogen degradation ability were isolated from 204 nitrate nitrogen degradation strains.These strains were identified as bacillus sp,bacillus aryabhattai,bacillus megaterium,bacillus megaterium,bacillus aryabhattai,bacillus megaterium and Advenella incenate through the analysis method of morphology,physiological and biochemica and molecular biology.The highest amount of nitrate nitrogen degradation was 282.98μg/mL.2、The construction of composite microbial systemAntagonism experiment were carried between four phosphate-solubilizing strains and seven nitrate nitrogen degradation strains.The results showed that eleven strains had not antagonism each other.The optimal strain composition of phosphatesolubilizing strains system and nitrate nitrogen degradation strains system and optimal inoculum size of strain system were further optimized.The results showed that the optimal fungi composition of phosphate-solubilizing strains system was P1,P2,P4 and the inoculum size was 1%,2%,3% respectively;the optimal bacteria composition of nitrate nitrogen degradation strains system was JN1,JN2,JN3,JN4,JN5,JN6,JN7 and the inoculum size was 3%,1%,3%,3%,3%,2%,3% respectively.3、The pot experiment of sweet pepperThe straw organic fertilizer of lab-made and microorganism system were conducted pot experiment.The main conclusions were as follows: 1)The treatment groups of every organic fertilizer cause a certain degree effects on imporving soil physical properties.Among them,the effect of straw organic fertilizer treatment group was the best.The second was the straw organic fertilizer+chicken manure treatment group.The last was the chicken manure treatment group.The treatment groups of every organic fertilizer can improve the pH value of acidified soil.At the same time,the treatment group of straw organic fertilizer can be reduced the soil salt content;2)The application of phosphate-solubiliing strains system alone can increase the organic content of nitrate nitrogen and organic matter of straw organic fertilizer treatment group,but the content of soil nitrate nitrogen and salt can be reduced by adding the nitrate nitrogen degradation strains system;the application of nitrate nitrogen degradation strains system alone and the combination with the phosphate-solubilizing strains system can promote plant growth and development.However,the application of phosphate-solubilizing strains system alone can inhibit plant growth and development;3)The index of plant growth and development had significant positive correlation with each other and it had significant negative correlation with nitrate nitrogen;the soil physical properties had significant correlation each other;available phosphorus had significant positive correlation with pH value,electricconductivity and organic matter.4)Based on the above points,this experiment took four treatment group: saline soil + straw organic fertilizer(15%)+ phosphate-solubiliing strains system(75mL)+ nitrate nitrogen degradation strains system(75mL)as primary way of improving greenhouse soil.