A Novel Bio-Fertilizer Produced by Prickly Ash Seeds with Biochar Addition Induces Soil Suppressiveness against Black Shank Disease on Tobacco

A novel bio-fertilizer, produced from prickly ash seeds (PAS), Bacillus subtilis and biochar, was evaluated for its disease-preventing potential on tobacco black shank caused by Phytophthora nicotianae. The results showed that biochar promoted the growth of Tpb55 in PAS increased pH organic fertilizer. final concentration B. could reach 1.7 × 1010 cfu g−1 biological fertilizer (PBB) under optimal medium conditions solid-state fermentation. PBB exhibited a strong fumigation effect P. nicotianae, including inhibiting mycelium growth, reducing disease severity decreasing pathogen population rhizospheric soil. treatment also significantly increase acidified soil improve nutrition content such as available K, alkali hydrolysable N carbon. High-throughput pyrosequencing 16S 18S rRNA genes revealed 4% addition had significant effects diversity richness fungi but not bacteria. microbial community structure shifted after treatment. Some potentially beneficial microbes Bacillus, Mucor, Cunninghamella, Chitinophaga Phenylobacterium were enriched, while Fusarium decreased. In conclusion, agricultural waste combined with can replace soybean source production biocontrol Tpb55, bio-fertilizer effectively control inhibition, nutrient improvement shifting rhizomicrobial community.