P-287 - Harnessing probiotics to enhance lettuce growth and microbiome composition in hydroponic systems

Understanding the intricate relationships between plants and their associated microorganisms is essential for enhancing plant health and productivity. While the microbiomes of soil-grown crops have been widely researched, those of hydroponically grown crops remain largely unexplored. Plant health-promoting microorganisms, such as probiotics, are becoming increasingly popular for agricultural production and sustainability. However, some products on the market are advertised as suitable for hydroponic systems but are generally designed for field-based cultivation. To understand the role of these microbes as biostimulant/biocontrol agents in hydroponic systems and their overall impact on plant health, we investigated the potential of using probiotics to enhance lettuce growth and yield in hydroponics. We conducted experiment in a controlled environment, evaluating lettuce growth and analysing the bacterial communities associated with lettuce using Nanopore amplicon sequencing. The results indicated that while some probiotics effectively increased lettuce yield compared to the control, the majority were not effective. Proteobacteria was the most abundant bacterial group across all probiotic treatments, followed by Bacteroidetes and Planctomycetota. However, certain genera exhibited significant changes in abundance following probiotic application, including some identified as plant-beneficial microbes.