P-124 - inhibition of pathogen growth through competition among microorganisms for sugars in flowers

Fire blight, a bacterial plant disease caused by Erwinia amylovora primarily affects apple and pear production. For bacterial plant pathogens, there are few effective control agents beyond certain chemical agents such as copper-based compounds, antibiotics, or bacteriophages. However, the use of chemical agents or antibiotics can lead to environmental pollution or the emergence of antibiotic-resistant strains that may pose risks to human health. Consequently, there is an urgent need to develop methods to drastically reduce the use of such agents or to create eco-friendly alternatives for disease control. In this study, we investigated changes in the microbiome and transcriptome associated with apple blossom development. Based on these findings, we hypothesized a correlation between arabinogalactan secretion in the stigma and the dominance of Pantoea spp. in flowers and conducted further analysis to investigate this relationship. Pantoea spp. rapidly consumed various sugar sources, including arabinogalactan, and effectively controlled the colonization of E. amylovora in flower. Furthermore, we selected microorganisms capable of rapidly metabolizing multiple sugar sources and constructed a microbial consortium to evaluate its efficacy in preventing E. amylovora infection in flowers.