Deciphering Underlying Drivers of Disease Suppressiveness Against Pathogenic Fusarium oxysporum

Abstract

Soil-borne diseases, especially those caused by fungal pathogens, lead to profound annual yield losses. One key example for such a disease is Fusarium wilt disease in banana. In some soils, plants do not show disease symptoms, even if the disease-causing pathogens are present. However, the underlying agents that make soils suppressive against Fusarium wilt remain elusive. In this study, we aimed to determine the underlying microbial agents governing soil disease-suppressiveness. We traced the shift of microbiomes during the invasion of disease-causing Fusarium oxysporum f. sp. cubense in disease-suppressive and disease-conducive soils. We found distinct microbiome structures in the suppressive and conducive soils after pathogen invasion. The alpha diversity indices increased (or did not significantly change) and decreased, respectively, in the suppressive and conducive soils, indicating that the shift pattern of the microbiome with pathogen invasion was notably different between the suppressive and conductive soils. Microbiome networks were more complex with higher numbers of links and revealed more negative links, especially between bacterial taxa and the disease-causing Fusarium, in suppressive soils than in conducive soils. We identified the bacterial genera Chryseolinea, Terrimonas, and Ohtaekwangia as key groups that likely confer suppressiveness against disease-causing Fusarium. Overall, our study provides the first insights into agents potentially underlying the disease suppressiveness of soils against Fusarium wilt pathogen invasion. The results of this study may help to guide efforts for targeted cultivation and application of these potential biocontrol agents, which might lead to the development of effective biocontrol agents against Fusarium wilt disease.

Auxiliary Rapid Identification of Pathogenic and Antagonistic Microorganisms for Coptis Chinensis Root Rot by High-throughput Sequencing

“…Liu et al 21 used 16S rRNA and ITS sequencing to identify the endophytic and rhizosphere microbiomes involved in ginseng rust roots. Ou et al 24 used Illumina metabarcoding to trace changes in microbiome composition upon pathogens invasion over time, to investigate the expected changes in the microbiome between conductive and suppressive soil upon pathogen invasion, and to identify potential microbial agents that induce soil suppressiveness against Fusarium wilt disease.…”

“…High-throughput sequencing technology is a powerful tool to reveal the ora of plant diseases. It can detect plant pathogenic microorganisms and discover bene cial microorganisms that may inhibit plant pathogens and promote host growth, therefore providing possible solutions for plant pathogen infection and prevention [21][22][23][24][25][26] . Liu et al 21 used 16S rRNA and ITS sequencing to identify the endophytic and rhizosphere microbiomes involved in ginseng rust roots.…”

Changes in bulk soil affect the disease-suppressive rhizosphere microbiome against Fusarium wilt disease

“…Furthermore, Cupriavidus can produce lipopeptide siderophores such as taiwachelin [39] which may mediate in competition for iron and induced resistance to suppress pathogenic fungi [40] . Although there has been no report that the genera Terrimonas and Ohtaekwangia possess specific biocontrol activity against F. oxysporum, these two genera were identified as key groups that confer soil disease-suppressiveness against Fusarium wilt pathogen invasion [41] . In addition, species in the Chitinophagaceae and Cytophagales were reported to be producers of chitinolytic enzymes which are involved in fungal cell wall lysis and chitin degradation [42] .…”

“…In addition, species in the Chitinophagaceae and Cytophagales were reported to be producers of chitinolytic enzymes which are involved in fungal cell wall lysis and chitin degradation [42] . The Gp6 group was reported to occur in higher relative abundance in potato common scab and banana Fusarium wilt disease-suppressive soils than in disease-conducive soils [4,41,43] . Despite this indication, the actual role of Gp6 influencing disease suppression is still unknown.…”

Soil microbiota manipulation and its role in suppressing soil-borne plant pathogens in organic farming systems under the light of microbiome-assisted strategies

“…The BCA populations involved in soil disease suppression against Fusarium oxysporum f. sp. cubense of banana were tracked in both suppressive and conducive soils during the pathogen colonization [172]. The hypervariable V4 region of the bacterial 16S rRNA gene was amplified using the primer pair 520F/802R.…”