Additive fungal interactions drive biocontrol of Fusarium wilt disease

Abstract

Summary Host‐associated fungi can help protect plants from pathogens, and empirical evidence suggests that such microorganisms can be manipulated by introducing probiotic to increase disease suppression. However, we still generally lack the mechanistic knowledge of what determines the success of probiotic application, hampering the development of reliable disease suppression strategies. We conducted a three‐season consecutive microcosm experiment in which we amended banana Fusarium wilt disease‐conducive soil with Trichoderma‐amended biofertilizer or lacking this inoculum. High‐throughput sequencing was complemented with cultivation‐based methods to follow changes in fungal microbiome and explore potential links with plant health. Trichoderma application increased banana biomass by decreasing disease incidence by up to 72%, and this effect was attributed to changes in fungal microbiome, including the reduction in Fusarium oxysporum density and enrichment of pathogen‐suppressing fungi (Humicola). These changes were accompanied by an expansion in microbial carbon resource utilization potential, features that contribute to disease suppression. We further demonstrated the disease suppression actions of Trichoderma‐Humicola consortia, and results suggest niche overlap with pathogen and induction of plant systemic resistance may be mechanisms driving the observed biocontrol effects. Together, we demonstrate that fungal inoculants can modify the composition and functioning of the resident soil fungal microbiome to suppress soilborne disease.

Trichoderma-induced restructuring of the cucumber rhizosphere microbiome and the effect of a synthetic, cross-kingdom microbial community on Fusarium wilt disease and growth in cucumber

“…Microorganisms are important indicators of soil health 29 . Signi cant changes in microbial structure and composition may affect the ability of a soil to inhibit plant pathogens and disease development and promote plant growth 30,31 . In the present study, PCoA analysis based on Bray-Curtis distance revealed that bacterial taxa are more responsive to continuous cropping of cucumbers, potentially because of the consistent and persistent addition of carbon, nitrogen, and other elements into the soil associated with the growth and management of cucumber production.…”

Fungi beyond limits: The agricultural promise of extremophiles

“…For example, a Trichoderma guizhouense-amended biofertilizer stimulated the colonization of plant roots by indigenous beneficial fungi (Humicola spp. ), contributing to plant health (Tao et al, 2023).…”

Dissection of rhizosphere microbiome and exploiting strategies for sustainable agriculture

“…For instance, the application of a Fusarium-predatory bacterium can suppress cucumber Fusarium wilt by regulating the rhizosphere microbiome (Ye et al, 2020). Biofertilizers containing plant beneficial microbes have been shown to suppress wilt disease caused by Ralstonia solanacearum (Deng et al, 2022) and Fusarium oxysporum (Tao et al, 2023) by modulating pathogen-suppressing rhizosphere microbiomes. Schmitz et al (2022) showed that salt tolerance in plants supplemented with synthetic bacterial communities relies on the presence of the rhizosphere microbiome, suggesting that inoculation can improve the stress tolerance of host plants by regulating the rhizosphere microbiome.…”