Bioassay-guided isolation of a novel chemoattractant for Ralstonia solanacearum in tomato root exudates

Tomato root exudates were analyzed using a bioassay to detect the chemoattractant for Ralstonia solanacearum . An activated charcoal-adsorbed fraction of root exudates from tomato cultivar Oogata-fukuju had chemoattractant activity for R. solanacearum strain MAFF 730138. The active component, purified using a Sep-Pak C18 cartridge, an activated charcoal column, diol-modified silica gel, and NH 2 -modified silica gel, is a new hydrophobic attractant. The final purified fraction produced a single peak in a diol-modified silica gel HPLC analysis.