Influence of phosphorus on the colonization of barley rhizosphere by microorganisms

The mineral phosphorus supply produced two outbreaks in the bacterial popul ation of the barley rhizosphere and rhizoplane but inhibited the growth of fungal mycelium. The inhibition of mycelial growth might be due to the exud ation of specific inhibitors by barley roots, since the most pronounced inh ibition was observed at high doses of supplementary phosphorus.