Reduction of banana fusarium wilt associated with soil microbiome reconstruction through green manure intercropping

Abstract

Fusarium wilt of banana, also known as Panama disease, caused by the pathogen Fusarium oxysporum f. sp. cubense tropical race4 (Foc4) is one of the most destructive diseases and currently threatens banana production around the world. In this study, pot and field experiments were conducted to assess the control effect of banana intercropping with five intercropping green manures (Crotalaria acicularis, Sesbania sesban, Melilotus officinalis, Vicia villosa and Trifolium repens) on banana Fusarium wilt in high disease incidence soil. The soil microbiome was analysed using the MiSeq Illumina sequencing platform. The results showed that compared with banana monoculture, five intercropping treatments significantly reduced the incidence of banana Fusarium wilt and decreased the richness and diversity of soil fungi, among which V. villosa and T. repens intercropping treatment showed greater effect in disease suppression than the other treatments. The abundance of Aspergillus was increased, while the number of culturable Fusarium oxysporum was decreased in all five intercropping treatments compared with the banana monoculture treatment. A structural equation model showed that the changes in soil organic matter and NH4+-N content caused by intercropping may play a key role in the change of the soil fungal community and the reduction of banana Fusarium wilt incidence. In summary, this study provides an approach to intercropping green manures to unravel the biological basis of the disease-suppressing microbiome in the context of agricultural practices and soil management.