The invention relates to the technical field of
plant disease prevention and treatment, in particular to a
fungicide composition for preventing and treating
plant fungal diseases caused by alternariaalternata and a preparation method and use of the
fungicide composition. The
fungicide composition for preventing and treating the
plant fungal diseases caused by the
alternaria alternata is preparedfrom the components in parts by weight: 20 parts of endophytic
streptomyces violascensfermentation liquid of
ginkgo biloba, 30-50 parts of an exotesta extract of the
ginkgo biloba and 1-2 parts of Tween 80, and the fungicide composition is used for preventing and treating the plant diseases caused by the
alternaria alternata after being diluted with water for 100-150 times. The preparation methodof the fungicide composition comprises the steps of the extraction of the exotesta extract of the
ginkgo biloba, the preparation of the endophytic
streptomyces violascensfermentation liquid of the
ginkgo biloba and the compounding of the endophytic
streptomyces violascensfermentation liquid of the
ginkgo biloba and the exotesta extract of the
ginkgo biloba. According to the fungicide composition,the incidence and
disease indexes of the plant diseases caused by the
alternaria alternata can be effectively lowered, the relative inhibition rate is increased, the excellent prevention and treatmenteffect is achieved, and the advantages of stability,
low toxicity, no residue, no environmental
pollution and the like are achieved.