Complex microbial inoculant for straw compost maturity and european corn borer prevention, as well as preparation and application of complex microbial inoculant

The invention discloses a complex microbial inoculant for straw compost maturity and european corn borer prevention, as well as preparation and application of the complex microbial inoculant. The complex microbial inoculant comprises a mixed strain and an additive, wherein the mixed strain comprises trichoderma harzianum, bacillus licheniformis and beauveria bassiana, and is prepared by the following steps: inoculating three bacterial strain test tube slant culture media subjected to purification and rejuvenation to corresponding fluid nutrient media respectively, performing fermentation to obtain liquid strains, inoculating the three fermented fluid strains into a solid culture medium, culturing for 48-72h at the temperature being 28-30 DEG C, dying, and crushing; the additive comprises glucose, superphosphate and humic acid; the mixed strain and the additive are mixed according to a mass ratio being (2.0-8.0):1.0 so as to obtain the complex microbial inoculant. The mixed strain and the additive are mixed so as to play a relatively good synergy role; the complex microbial inoculant has the capabilities of increasing the speed of straw compost maturity, killing european corn borer larvae and pupae, reducing the incidence of european corn borer, reducing the harm, improving granhle soil structures, increasing the fertilizer utilization rate and playing a yield increasing role.