Effects of two types of microbial fertilizers on growth of olive and diversity of rhizosphere soil microorganisms

<bold>Objective</bold> In order to investigate the effect of microbial fertilizer on the growth of olive and the microbial diversity of inter-root soil，the present study conducted a field experiment of microbial fertilizer with 6-year-old olive as the research object. <bold>Method</bold> Using conventional agrochemical analysis of soil and Illumma MiSeq high-throughput sequencing technology，changes in olive growth，inter-root soil physicochemical properties and microbial community structure under different application rates of two microbial fertilizers were investigated. <bold>Result</bold> Under the same application rate，the treatment with microbial fungicide had better crown，plant height and diameter growth and higher soil nutrient content than those with biofungal composite； under different application rates，olive plants grew best and had the highest soil nutrient content when 9 kg of microbial fungicide（W9）and 6 kg of biofungal composite（F6）were applied；both microbial fertilizers altered inter-root soil microbial abundance and diversity；the application of microbial fungicide reduced soil fungal abundance and diversity while increased soil bacterial species abundance and diversity.The fungal phylum with higher relative abundance in the rhizosphere soil under each treatment were Ascomycetes and Stramenophora，and the bacterial phyla were Ascomycetes，Acidobacteria，and Actinobacteria；correlation analyses showed that the indicators of the agronomic characters of plants were positively correlated with Ascomycetes and Ascomycetes.Correlation analysis showed that the agronomic traits of the plants were positively correlated with Ascomycetes and negatively correlated with Aspergillus and Acidobacteria. <bold>Conclusion</bold> In general，the application effect of microbial inoculants is better than that of compound microbial inoculants under the same application rate. The best application results are obtained at 9 kg/plant for the microbial fungicide and 6 kg/plant for the composite biofungicide under the different application rate.