Studies on the rhizosphere and rhizoplane microflora of common-bean and barley.

Both broad bean and barley plants stimulated bacteria (total), N-fixing clostridia, Azotobacter ammonifiers, and aerobic cellulose-decomposers in their rhizosphere zone. The rhizosphere effects were generally positive until the 8th week of either plant growth. However, the rhizosphere effect differed according to type of plant, growth phase of each single plant, and type of micro-organism under study. The presence of high numbers of micro-organisms in the rhizoplane samples (washed ruptured roots) of each plant supports the evidence that roots of these plants are colonized with soil micro-organisms.