Arabidopsis uses distinct coumarins and bacterial pathways for pH-adaptive iron acquisition.

Arabidopsis employs pH-specific coumarins and bacterial pathways for iron acquisition, with bacterial genes prevalent in root microbiota and likely evolved before land plants.

• Why it matters: Understanding how plants adapt their iron uptake to different soil conditions and microbial interactions can improve strategies for enhancing plant growth in iron-limited soils, addressing a key agricultural challenge.
• What they did: Researchers examined Arabidopsis and root-associated bacteria across diverse soil pH conditions, revealing regulation of iron mobilization through host-controlled coumarin exudation and bacterial siderophore or reduction pathways, with bacterial genes widespread in microbiota.
• The result: Findings suggest that redox-active metabolite exudation is a common, ancient microbial-mediated adaptation for iron mobilization in non-graminaceous plants, enabling plants to better cope with soil iron deficiency.