Conditions in the Rhizosphere in Relation to Microbial Development

Abstract

Interactions between microbes and higher plants take place either on the roots or shoots. The interactions in the soil-root zone are more difficult to monitor and measure, and are certainly more difficult to control, because of the difficulty of access and the extreme complexity of the environment in which the interaction occurs. It is the purpose of this paper to examine some of the specialised physical and chemical conditions immediately around plant roots, so that the potential effect of these on the microbe-plant interaction can be better understood. The normal soil situation around a root is vastly different from that observed in water culture or in other artificial situations, and needs to be taken into account in any attempt at a rational genetic modification of rhizosphere organisms for improved disease control, nitrogen fixation or other beneficial effects.