Abstract
This mini-review focuses on the microbial production of phytohormones including auxins, cytokinins and ethylene derived from exogenously applied precursors. The L-tryptophan, adenine plus isopentyl alcohol and L-methionine have been found to promote the production of microbially-derived phytohormones in both pure culture studies and in soils. We have evaluated the applications of these precursors as agrochemicals to promote microbially-derived phytohormones in modifying plant growth and development. Soil amendments with these precursors to the rhizosphere of young seedlings has affected plant growth, develop
