Fermentation-based biological agent as well as preparation method and application thereof

The invention discloses a fermentation-based biological agent as well as a preparation method and application thereof. The biological agent is prepared by fermenting and culturing bacillus having a strong bacteriostatic effect on rice sheath blight disease in a culture medium containing scutellaria baicalensis enzymatic hydrolysate. The obtained biological agent can play a role in inhibiting harmful microorganisms in plant growth, and can increase the positive influence on plant growth. In order to solve the problems of poor stability, low bacteriostasis rate and the like of the raw material bacillus cereus of the microbial agent, a combined fermentation mode of the bacillus cereus and scutellaria baicalensis enzymatic hydrolysate is adopted, a fermentation medium is optimized, the bacteriostasis rate of the bacillus cereus is promoted to be obviously improved, and the growth promoting effect of the bacillus cereus on rice plants is greatly improved; the quality and the nutritional value of the rice are impro