Disease-suppressive soil and root-colonizing bacteria.

Soils in many areas suppress certain plant diseases. Understanding the basis for this disease suppressiveness could lead to improved plant health in less favorable areas. Some forms of disease suppression may be caused by bacteria in the genus Pseudomonas which aggressively colonize root surfaces. Increased plant growth and yield are closely associated with the capacity of some of these bacteria to produce iron-binding compounds called siderophores. This article addresses the biological characteristics of these soil-bome root epiphytes, their contribution to plant health, and their potential use in biotechnology.