P-350 - Influence of organic farming on the rhizosphere microbiome and root gene expression in common bean

The expression of common bean root genes (Phaseolus vulgaris L.) under different farming systems (organic, OF, and conventional, CF) was investigated using genomic tools: metabarcoding of the rhizosphere and RNA-seq of the plant roots. Metabarcoding analysis (16S and ITS) of rhizospheres from the bean cultivar ‘Andecha’ revealed a higher fungal presence in OF and greater prokaryotic abundance in CF. Significant differences in alpha diversity were detected for both prokaryotes and fungi between the soils of both farming systems, while beta diversity revealed distinct microbial community structures. MetagenomeSeq differential abundance analysis showed enrichment of Rhizobium and Chitinophaga in OF, whereas Pirellula and Terrimonas were more abundant in CF. Among fungi, Conocybe and Funneliformis dominated in OF, while Claroideoglomus, Mortierella, and Rhizophagus were enriched in CF. RNA-seq analysis of roots identified 1047 differentially expressed genes (NOISeq): 866 in OF and 181 in CF, suggesting significantly enhanced metabolic activity in OF. Gene ontology enrichment analysis highlighted processes related to oxidative stress response, secondary metabolism, and nutrient transport in OF. These findings underscore the impact of farming systems on root-associated microbial communities and their implications in root gene regulation, influencing plant stress responses and nutrient uptake in common bean.