N-(3-Indolylacetyl)-L-alanine -d 4 (Indoleacetylalanine-d 4 ) is the deuterium labeled N-(3-Indolylacetyl)-L-alanine. N-(3-Indolylacetyl)-L-alanine is an indoleacetylamino acid. N-(3-Indolylacetyl)-L-alanine appears to increase callus growth and reduces the ability of growths to differentiate into shoots of Phalaenopsis orchids.