Auxin-Environment Integration in Growth Responses to Forage for Resources

Plant fitness depends on the adequate morphological adjustment to the prevailing conditions of the environment. Therefore, plants sense environmental cues through their life cycle, including the presence of full darkness, light, or shade, the range of ambient temperatures, the direction of light and gravity vectors, and the presence of water and mineral nutrients (such as nitrate and phosphate) in the soil. The environmental information impinges on different aspects of the auxin system such as auxin synthesis, degradation, transport, perception, and downstream transcriptional regulation to modulate organ growth. Although a single environmental cue can affect several of these points, the relative impacts differ significantly among the various growth processes and cues. While stability in the generation of precise auxin gradients serves to guide the basic developmental pattern, dynamic changes in the auxin system fine-tune body shape to optimize the capture of environmental resources.