Combined Fermentation Of Plant Growth-Promoting Rhizobacteria And Joint Application Of Exogenous Substances

In recent years, extensive use of fertilizers resulted in soil compaction, soi l microbial species and quantity decreasing, insufficient soil fertility, and crop quality decline.Biological fertilizer not only can promote crop growth, improve crop quality, also can improve soil biological activity, promote the soil ecologic al system of material circulation.Existing biological fertilizer has some shortcom ings, such as the single microbial, immature fermentation process, inorganic nut rients and organic nutrients imbalance. To solve these problems, this study use d three Plant Growth- Promoting Rhizobacteria(Pseudomonas aurantiaca JD37,Bacillus amyloliquefaciens S3-1, Bacillus Megaterium LY11). Then combined t he composite microbial inoculum with other xenobiotics(organic nutrients, inor ganic nutrients). The whole biological organic fertilizer was developed, and its effects on the yield and quality of crops and the soil biological activity were discussed.This study used the simplex centroid design method to combine composite microbial inoculum, and used response surface method to obtain the optimal f ermentation medium formula.Through orthogonal experiment to optimize the fer mentation conditions. Soluble phosphorus was chosen as the functional index, t he optimum conditions of phosphate solubilization were optimized by orthogona l experiments, and the relationship between the rate of phosphate solubilization and the growth rate was explained according to the kinetics of substrate cons umption.The field test confirmed that the composite microbial inoculum had a role in promotingon growth of spinach and soil enzyme activity. 7.5L compoun d bacteria fermentation liquid adding different inorganic nutrients(A:20g fertiliz er, B:10g fertilizer, C:10g fertilizer + 1% chloride lanthanum), and then the pe at saturated adsorption composite agent, mixed with earthworm manure(Vt:Ve=1:1), and applied in field experiment.Data show that The addition of low doses of rare earth not only enriched the kinds of inorganic nutrients, but also can e ffectively promote the growth of spinach, and better to maintain soil microbial quantity each period, slowing down of the decrease of soil p H, moisture loss and salinity increase.Compared with the control group, the content of chlorophy ll a, Vc and soluble solid content in spinach was significantly increased after applying the whole microbial fertilizer C. Compared with the traditional fertilize r group, the content of nitrate and nitrite decreased significantly.The experimental results show that by optimizing the fermentation process, can improve the composite microbial living bacteria number and the dissolved phosphorus content. The feasibility of this method is proved, which provides some references for compound fermentation. In order to solve the imbalance of inorganic nutrients and organic nutrient content, microbial agent, together with the other xenobiotics(organic and inorganic nutrients) in different proportion prepared three kinds of whole microbial fertilizer, and applied to the field of crops..It was found that the whole microbial fertilizer C could promote the growth of crop growth, and had better effect on soil enzyme activity, and decreased the content of nitrate and nitrite in crops.The results showed that added a small amount of low dose rare earth and chemical fertilizer into the whole microbial fertilizer can meet the nutrient demand of spinach,significantly improved the soil quality, controlled soil microflora effectively,improved soil fertility, increased crop yield and quality. The addition of rare earth can enrich the types of inorganic nutrients, while reducing the use of chemical fertilizers.These studies lay the foundation for the application of the whole microbial fertilizer in promoting the growth of crops and improving the quality of crops.