Unintended effects from 2,4-D tolerance
Plants that seem tolerant to some herbicides may not be entirely unaffected by them, researchers from the US Purdue University (West Lafayette, Indiana) have found. Results from a recently published study show that an unintended target of the synthetic auxin herbicide, 2,4-D, is the protein that modulates endogenous auxin (indole acetic acid – IAA) levels in plants. The protein, ABCB4, is the key component of the “fine tuning” mechanism that coordinates plant root growth. The protein is expressed on the surface of root hairs, where it acts as a bi-way transporter, shunting auxin into and out of cells.