The attachment of bacteria to roots constitutes the first physical step in many plant–microbe interactions. These interactions exert both positive and negative influences on agricultural systems depending on whether a growth-promoting, symbiotic or pathogenic relationship transpires. A common biphasic mechanism of root attachment exists across agriculturally important microbial species, including Rhizobium, Agrobacterium, Pseudomonas, Azospirillum and Salmonella. Attachment studies have revea...