Studies on Plant Growth Accerating Substances

Part I. The Isolation Method of Soil Microbes which Produce Plant Growth Accerating Substances

抄録

By the aid of Chlorella grown on an agar plate a new method has been devised to detect soil microbes which produce plant growth accelerating substances. From the results of examining 3, 300 soil microbes by this method, it was shown that the soil microbes could be divided into three groups according to their effect on the growth of Chlorella, that is, Chlorella growth accelerators, inhibitors and non-accelerators. By the cultivation of some green plants in the existence of some of these microbes or their culture filtrates, it was further shown that their effect on the growth of Chlorella and that of plants were in parallelism as a rule. The growth accelerating substances that are produced by soil microbes found in the present research were shown by the comparative experiment to be quite different from the substances previously known.