This is just like phototropism, in that auxin in the root inhibits growth and auxin in the stem promotes growth.

Plants rely on abscisic acid (ABA), a crucial plant ... the researchers' restoration of normal root growth in these mutants by externally adding auxin. The results were consistent between maize ...

Knowing how pathogens affect root growth and overall biomass ... The most common auxin in nature is called Indole-3 acetic acid – IAA for short. In plants, IAA affects cells' length, plants ...