[Effects of lime and ammonium carbonate fumigation coupled with bio-organic fertilizer application on banana fusarium wilt and bacterial community.].

Taking banana continuous planting soil with high banana fusarium wilt disease incidence as a test site, we examined the effect of lime and ammonium carbonate fumigation coupled with bio-organic fertilizer on the suppression of banana fusarium wilt disease and the structure and composition of bacterial community, using real-time quantitative PCR and high-throughput sequencing. The results showed that the disease incidence was reduced by 13.3% and 21.7% in the treatments of LAOF (lime and ammonium carbonate fumigation coupled with organic fertilizer) and LABF (lime and ammonium carbonate fumigation coupled with bio-organic fertilizer), respectively, compared with OF (application of organic fertilizer without fumigation), while the copy number of Fusarium was decreased by 22.4% and 33.0%, respectively. Compared with non-fumigation treatment, lime and ammonium fumigation coupled with different fertilizer applications significantly reduced bacteria richness and diversity, with different community structure, while fumigation had a decisive effect on bacterial community composition. Bacterial richness and diversity of LABF were lower than those of other treatments, while microbial community structure was clearly disparate from other treatments. Compared with non-fumigation treatment, the relative abundance of Mizugakiibacter, Brucella, and Rhodanobacter were significantly improved in the fumigation coupled with different fertilization treatments. Those three genera in LABF were higher than those in LAOF, with significant differences for the relative abundances of Mizugakiibacter and Brucella. Therefore, fumigation combined with bio-organic fertilizer application could reduce the copy number of pathogen, alter soil bacterial community structure and stimulate beneficial bacteria in the resident soil, and thus reduce the occurrence of banana fusarium wilt.