Plant-Microbe Interactions, Volume 1 Many plant-microbe interactions have agronomic importance because of either beneficial (e.g., nitrogen fixation or biocontrol) or detrimental (e.g., pathogen­ esis) effects. Although these systems have been the subjects of scientific re­ search for many years, recently there has been a tremendous increase in our knowledge of them. The increases in this research have followed a similar general increase in plant science research. Classical plant science research disciplines (e.g., agronomy, breeding, plant physiology, systematics, etc.) have been affected by an increased focus on molecular biology. These new technologies, as well as advances in other areas, have the effect of blurring the traditional borders between research disciplines. Another factor influencing the development of this research is the increased attention given to environmental issues. These concerns have been brought about by debate over the release of genetically modified organisms and the general concern over environmental quality. Thus, research areas focused on plant-microbe interactions are presently in a period of great excitement and growth that shows every sign of continuing far into the future. As in most research areas, the rate of advance and breadth of disciplines involved in the study of plant-microbe interactions make it impossible for the average researcher or student to stay abreast of the primary scientific literature.