Ability Of Phosphate Solubilizing Strain P7 And Its Effect On Soil And Fruit Of Jujube Orchard

A large part of the phosphorus in the soil is fixed by the metal elements in the soil as insoluble phosphate under complexation,resulting in low utilization of phosphorus.For this reason,people often put more and more chemical fertilizers into the soil,which in the long run causes serious damage to the soil.The studies have found that the application of microbial inoculants can effectively increase the content of soluble phosphorus in the soil and improve the utilization rate of phosphate fertilizer.However,due to the different phosphate solubilization capabilities of different microbial strains,the phosphorus solubilizing ability of phosphorus strains will be affected to different degrees of influence with the different carbon,nitrogen and phosphorus source environments.Colonization in different environments,there are significant differences in the phosphorus solubilizing ability of phosphorus solubilizing strains.Therefore,the study took the high-efficiency phosphate solubilizing strain P7 selected by the research team from the Xinjiang jujube orchard in the early stage as the research object.Under different carbon,nitrogen and phosphorus sources,the effective phosphorus content and the dynamic change of p H were determined to study and analyze the effect of carbon,nitrogen,and phosphoric acid on the phosphorus solubilizing strain P7.The organic acid content,phosphatase activity,and the number of microorganisms are measured at the same time to explore the mechanism of phosphorus solubilization and to screen the best carbon,nitrogen and phosphorus source environment.Through field fertilization experiments,soil nutrients and nutrient quality of jujube fruit are determined to test the colonization effect of high efficiency phosphorus strains;after analyzing the data by variance analysis,comparative analysis,and factor analysis,we have the following conclusions with the comprehensive analysis:1.Different carbon,nitrogen and phosphorus sources have certain effects on the phosphate solubilizing ability of phosphate solubilizing bacteria strain P7.The single factor test results show that among different carbon sources,when soluble starch is the only carbon source,the phosphorus solubilizing strain has the strongest ability to dissolve phosphorus;among different nitrogen soures,when ammonium sulfate is the only nitrogen source,the phosphorus solubilizing ability of P7 is the strongest;among different phosphorus sources,when calcium phosphate is the only phosphorus source,the phosphorus solubilizing strain P7 has the strongest phosphorus solubilizing ability;among different C/N(soluble starch:ammonium sulfate),when C/N is 35:1,the phosphorus-solubilizing strain P7 has the strongest phosphorus-dissolving ability;in the fermentation liquid of different treatments,the change of the content of water-soluble phosphorus is always inversely proportional to the p H value.2.After qualitative and quantitative analysis of 7 kinds of the organic acids in the fermentation liquid of each treatment,it shows that the contribution of organic acids to the phosphorus solubilizing ability of the phosphorus solubilizing strain P7,of which malic acid is the highest,followed by succinic acid,and the rest of the organic acids ranked in citric acid>tartaric acid>oxalic acid>maleic acid>fumaric acid.There is no significant correlation between the activity of alkaline phosphatase and the content of water-soluble phosphorus in each treatment.Therefore,alkaline phosphatase has no significant effect on the dissolution of calcium phosphate in phosphorus solubility strain P7.3.In Aksu and Kashgar,all treatments are compared with blank treatment,the p H and electrical conductivity of the rhizosphere soil of the jujube tree decreased,and there is an increase in the contents of available nitrogen,available phosphorus,available potassium and organic matter.The overall application effect of each treatment shows the rule of GFPP7> N22P7P18K24> CK3>CK2>CK1.4.The p7 labeled with rifampicin grows to the peak value at 30 days after colonization of phosphate solubilizing strain in the rhizosphere of jujube trees in Aksu and Kashgar jujube orchards,and then decreases slowly.Compared with the experimental site in Kashgar,the growth status of phosphate solubilizing strain in the experimental site in Aksu is better,but from the perspective of growth-promoting effect,the experimental site in Aksu is not as good as in Kashgar.5.The nutritional quality of jujube fruit in Aksu and Kashgar jujube orchards was determined,which showed that the nutritional quality of jujube fruit in each treatment was higher than that in the blank treatment.In terms of the growth rate,GFPP7 treatment is the largest,followed by N22P7P18K24 treatment.There is no significant difference in nutritional quality of jujube fruit among treatments in Aksu area.On the whole,the contents of soluble sugar,soluble protein,VC,total phenols and flavonoids in the jujube fruits of Kashgar experimental sites are higher.