Increased interest in the basic biology of plants and microorganisms stems from the fact that crop productivity is directly affected by plant-microbe interactions. In spite of the fact that plants exist in the environment amongst diverse species of microorganisms, only a few ever establish a direct relationship. Emerging awareness concerning the indirect effect of microbial association on plant growth and the possibility of using one microbe against another for controlling pathogenic interactions is at the genesis of new fields of studies. The primary reason for a microbe to associate with-...

Research on the interaction between plants and microbes has attracted considerable attention in recent years. The use of modem genetic techniques has now made possible a detailed analysis both of plant and of microbial genes involved in phytopathogenic and beneficial interactions. At the biochemical level, signal molecules and their receptors, either of plant or of microbial origins, have been detected which act in signal transduction pathways or as co-regulators of gene expression. We begin to understand the molecular basis of classical concepts such as gene-for-gene relationships,...

Interdependence between species is a law of nature. The degree of this interdependence is vividly evident in the plant-microbial world. Indeed, there is no axenic plant in nature and one finds various forms of interac- tions between these two kingdoms ranging from completely innocuous to obligate parasitic. Most of these interactions are poorly understood at the molecular and physiological levels. Only those few cases for which a molecular picture is emerging are discussed in this volume. With the advent of recombinant DNA technology and the realization that some of these interactions are...