Influence of bio-fertilizers on control of banana wilt disease and soil microbial diversity.

Banana wilt was a soil-borne disease caused by Fusarium oxysopoyum f. sp. cubens, and its spread has seriously affected the development of the banana industry. The combination of mature organic fertilizer-compost (OF) with three bacteria strains (Bacillus subtilis,Bacillusmucilaginosus and Bacillus megaterium) constructed bio-organic fertilizer (BOF) and biocompound fertilizer(BCF). Control effects of OF, BOF and BCF (comparison of the normal state with sterilization ) on banana wilt disease were studied and the soil bacterial community diversity was investigated by Biolog Eco plate under pot experiment of Musa paradisica (AAB). The results showed that three kinds of fertilizers had different effect on biological control of banana wilt disease. Disease index of BOF or BCF treatment was significantly lower than that of the single Foc. However, the difference was insignificant between OF and Foc. Control effect of BOF and BCF on banana wilt disease were 53.8% and 61.5% respectively. Compared BOF or BCF with its sterilization treatment and OF, it was concluded that functional bacteria played an important role in disease inhibition. BOF and BCF significantly promoted the plant growth: the fresh weight of plantlets with BOF and BCF were increased by 70.9% and 35.0% respectively compared with the single Foc. Biolog Eco plate experiment results showed that AWCD and Shannon diversity index ( H′ )of soil microbial community with the single Foc was higher than that of CK0, but they were lower compared with fertilizer treatments. Shannon eveness index (E) was insignificant among all treatments. Three kinds of fertilizer and Foc caused changes in soil microbial community, and the trend of AWCD and Shannon diversity index were reverse compared with control effect.