Effect of biofertilizer for suppressing Fusarium wilt disease of banana as well as enhancing microbial and chemical properties of soil under greenhouse trial

Biofertilizer application has been proposed as a strategy for the management of banana Fusarium wilt disease, which has severely decreased banana production. In this study, a 4-season pot experiment was conducted to evaluate the effects of sustainable biofertilizer application at low and high levels on banana Fusarium wilt disease suppression, soil chemical properties and microbial communities. The results showed sustainable biofertilizer application effectively controlled the disease, especially at a high level. Next-generation sequencing of the 16S rRNA and internal transcribed spacer (ITS) genes using the MiSeq platform showed that the soil bacterial and fungal communities in the treatment amended with a high level of biofertilizer (HBIO) were significantly different from a low level biofertilizer treatment (LBIO) or chemical fertilizer control (CF). Moreover, the abundance of Firmicutes and Bacillus was significantly increased, while the abundance of Acidobacteria, Bacteroidetes and Ascomycota was significantly decreased in the HBIO treatment compared with the CF control. Furthermore, the abundance of Fusarium was significantly reduced in the HBIO treatment compared with CF control and was slightly reduced (not significant) compared with the LBIO treatment. Redundancy analysis and Spearman correlation showed that Bacillus, Spartobacteria_genera and TM7_genera dominated in the HBIO treatment and they were positively correlated with the soil pH and the contents of total nitrogen and carbon and available phosphorus, which were negatively correlated with disease incidence. In conclusion, sustainable biofertilizer application suppressed the Fusarium wilt disease might through improving soil chemical condition and manipulating the composition of soil microbial community, including specific enrichment of Firmicutes (Bacillus), Anoxybacillus, Spartobacteria_genera, TM7_genera, Cantharellus, Pateramyces and Synchytrium.