Bacterial Growth and Development in the Rhizosphere of Gnotobiotic Cereal Plants

Abstract

The growth and development of a Curtobacterium sp., a Mycoplana sp. and a Pseudomonas sp. in the rhizosphere of gnotobiotic wheat, barley and maize plants were studied. When inoculated singly in the wheat or barley rhizosphere, each of the three species grew exponentially during the first 48–72 h and slowly thereafter. However, in the maize rhizosphere the Curtobacterium sp. showed only a small increase in numbers and the Mycoplana sp. had a long lag phase, a slower growth rate and a smaller final population than when it was inoculated into the wheat or barley rhizosphere. Interactions between these three species in various combinations and in different rhizospheres are described and some of the possible mechanisms involved are discussed.