ABSTRACT
This chapter describes the gradostat is an invaluable tool for the isolation of enrichment cultures where microbial consortia can interact even though some of the constituent species require mutually exclusive habitats. The gradostat provides an important tool for investigating competition between organisms. Some configurations of the gradostat can generate gradients of any desired shape, suggesting that it has valuable properties in genetic experiments designed to investigate the selection of mutant strains resistant to particular agents. One great advantage of homogeneous liquid culture devices like chemostats is that they are open systems capable of reaching steady states. Multistage continuous-culture systems can incorporate spatial and temporal heterogeneity though flow is in one direction only, and therefore reciprocal interactions between neighboring vessels is impossible. The chapter describes competition experiment is one of a family of interesting experiments that are possible in the gradostat. Bacterial film forms on the surface of inanimate or at any rate impermeable objects in most cases.
