Abstract:Partially replacing chemical fertilizer with organic fertilizer is the inevitable trend in guiding the rational fertilization, maintaining soil sustainable utilization and ensuring agriculture sustainable development in China. This study investigated the effects of partially replacing chemical nitrogen fertilizer (CNF) with organic fertilizer on the yield, quality and wild disease incidence of banana as well as soil microflora in order to provide theoretical basis for reducing the usage amount of CNF in the banana production. Four treatments were designed: T1, conventional CNF; T2, 20% of CNF replaced by organic nitrogen fertilizer (ONF); T3, 30% of CNF replaced by ONF; T4, 40% of CNF replaced by ONF. The growing conditions, disease incidence, yield and quality of banana, the nutrients and the amount of culturable microbial in soils were measured. The results showed that 20% to 40% of CNF replaced by ONF could meet the normal growth need of banana. Moreover, compared with T1, the substitution treatments (T2, T3 and T4) significantly increased the banana yield, meanwhile significantly reduced the disease incidence of banana fusarium wilt. In addition, the substitution treatments enhanced the contents of soil organic matter, available nitrogen, phosphor and potassium and mitigated soil acidification, which were all significantly negatively correlated with disease incidence. Furthermore, the quantities of culturable soil fungi and culturable fusarium were reduced, which were significantly positively correlated with disease incidence, and the quantity of culturable soil bacteria and B/F ratio were increased in the substitution treatments, principle components analysis showed that T4 and T3 treatments had the highest soil qualities, followed by T2, and T1 was the lowest. In conclusion, 30%-40% substitution treatment is optimal in promoting soil quality and improving soil microbial community structure for banana production.