Background
Fusarium
wilt of banana (
Musa
spp.) caused by the fungal pathogen
Fusarium oxysporum
f. sp.
cubense
(
Foc
) is a typical soilborne disease, that severely devastates the banana industry worldwide, and soil microbial diversity is closely related to the spread of
Fusarium
wilt. To understand the relationship between microbial species and
Fusarium
wilt, it is important to understand the microbial diversity of the
Fusarium
wilt-diseased and disease-free soils from banana fields.
Results
Based on sequencing analysis of the bacterial 16S
rRNA
genes and fungal internal transcribed spacer (ITS) sequences,
Foc
abundance, fungal or bacterial richness and diversity were higher in the diseased soils than in the disease-free soils. Although
Ascomycota
and
Zygomycota
were the most abundant fungi phyla in all soil samples,
Ascomycota
abundance was significantly reduced in the disease-free soils.
Mortierella
(36.64%) was predominant in the disease-free soils. Regarding bacterial phyla,
Proteobacteria
,
Acidobacteria
,
Chloroflexi
,
Firmicutes
,
Actinobacteria
,
Gemmatimonadetes
,
Bacteroidetes
,
Nitrospirae
,
Verrucomicrobia
and P
lanctomycetes
were dominant phyla in all soil samples. In particular,
Firmicutes
contributed 16.20% of the total abundance of disease-free soils. At the bacterial genus level,
Bacillus
,
Lactococcus
and
Pseudomonas
were abundant in disease-free soils with abundances of 8.20, 5.81 and 2.71%, respectively; lower abundances, of 4.12, 2.35 and 1.36%, respectively, were found in diseased soils. The distribution characteristics of fungal and bacterial genera may contribute to the abundance decrease of
Foc
in the disease-free soils.
Conclusion
Unique distributions of bacteria and fungi were observed in the diseased and disease-free soil samples from banana fields. These specific genera are useful for constructing a healthy microbial community structure of soil.