Indole-3-acetylglutamate was isolated from seeds ofGlycine maxL. cv Hark and identified by gas chromatography/mass spectrometry of thebis-methyl ester. Quantitative evaluation indicated that Hark soybeans contain 7.4 micromoles per kilogram of the glutamate conjugate. Conjugates with aspartate and glutamate have now been shown to account for essentially all of the bound indole-3-acetic acid present in seeds of soybean.