PLANT-GROWTH REGULATORS FROM ASH STRAINS OF PSEUDOMONAS-SYRINGAE SUBSP SAVASTANOI

Indole-3-acetic acid and its methyl ester have been isolated from cult ures of Pseudomonas syringae subsp. savastanoi isolated from ash. Howe ver, typical strains produced only small amounts of the auxins, wherea s relatively high amounts of the above phytohormones accumulated in th e culture of an atypical strain. No cytokinins were isolated from cult ures of the typical ash strains. Conversely, four cytokinins, namely d ihydrozeatin and its 9-beta-riboside, trans-zeatin riboside and its 1 ''-methyl derivative, were found in an atypical strain culture.