Root exudates, a key factor in the plant-bacteria interaction mechanisms

Abstract The astonishing fast development of molecular technologies allows humanity to discover new and exciting relationships in nature and also to understand their complex mechanisms. The growing knowledge on this relationship plant-microorganism has enabled us to describe the beneficial functions of bacteria in terms of plant growth promotion, especially under stress conditions, and on plant defense. Plant root exudates perform a vital function in the establishment, evolution and dynamics of this network, being capable to be used in the recruitment of beneficial bacteria and to form microbial communities in the rhizosphere. The present chapter compile and describe from a molecular point of view, the advances in the understanding of the functions of the root exudates, mainly focused on the two main groups of beneficial bacteria (those implicated in nitrogen-fixation and PGPR) and describing the cutting-edge technologies being implemented just now or in the near future.