Effect of pH on production of cytokinin-like substances by bacteria isolated from soil, rhizosphere and mycorrhizosphere of pine (Pinus silvestris L.).

Cytokinin-like substances were produced in higher amounts by soil isolates than by those isolated from the rhizosphere and mycorrhizosphere. However more bacterial strains isolated from the rhizosphere and mycorrhizosphere were capable of synthesizing cytokinin-like compounds. A distinct effect of pH on the production of these substances was found. It is suggested that zeatin and zeatin riboside are likely to be among the cytokinin-like substances detected.