The rhizosphere in soil environments refers to the narrow zone of soil influenced by the root and exudates. Microbial populations in the rhizosphere can be 10 - 100 times larger than the populations in the bulk soil. Therefore, the rhizosphere is bathed in root exudates and microbial metabolites and the chemistry and biology at the soil-root interface is governed by biotic (plant roots, microbes) and abiotic (physical and chemical) interactions.

The research on biotic and abiotic interactions in the rhizosphere should, thus, be an issue of intense interest for years to come. This...