#Id: 7514
#Unit 6. System Physiology – Plant
Although free IAA is the biologically active form of the hormone but toxic in high concentration, the vast majority of auxin in plants is found in a covalently bound state are considered hormonally inactive.
IAA has been found to be conjugated to both high- and low-molecular-weight compounds.
Low-molecular-weight conjugated auxins include esters of IAA with glucose or myo-inositol and amide conjugates such as IAA-N-aspartate.
High-molecular-weight IAA conjugates include IAAglucan