Screening of Fungal Diversity and Root Rot Antagonistic Bacteria in Rhizosphere Soil of Vaccnium sp.

In order to understand the microbial diversity of cultivated blueberry rhizosphere soil in Guizhou, screening microorganisms that have antagonistic effects on Vaccnium sp. root rot pathogens. The plate dilution method and the sputum culture method were used to study the fungal diversity of Vaccnium sp. rhizosphere soil and its antagonistic effect on the pathogen of Vaccnium sp. root rot. The results show that the colonies of 80 strains are significantly different. The BLAST alignment is carried out by using the strain rDNA-ITS sequence. The 80 strains are divided into 11 genera and 51 species. Their homologies are ranging from 99%−100%, of which, 65 isolates belong to 44 species of 9 genera in Ascomycota. The isolates from Gongronella and Mucor belong to Zygomycota, including 7 species, 15 strains. The Penicillium is the dominant genus of fungi in the Ascomycota isolates, and Penicillium shares 33.85% of the Ascomycota isolates. The Gongronella is the dominant genus of fungi in the Zygomycota isolates, and Gongronella shares 86.75% of the Zygomycota isolates. The quantity of rhizospherical fungi is 2.96×10⁵ cfu/g. The Shannon-Wiener index is 2.046 1. The Pielou index is 2.282 0 and the Margalef index is 0.853 3. The plat-confront method show that the inhibition rates of 22 strains are more than 50%, and the 8 strains are more than 70%. The Aspergillus japonicas, Trichoderma asperellum and Trichoderma gamsii show high inhibition rates, these strains are potential resources for bio-control of the Vaccnium sp. root rot disease.