Microbial iron reduction compensates for phosphorus limitation in paddy soils.

Limitation of rice growth by low phosphorus (P) availability is a widespread problem in tropical and subtropical soils because of the high content of iron (Fe) (oxyhydr)oxides. Ferric iron-bound P (Fe(III)-P) can serve as a P source in paddies after Fe(III) reduction to Fe(II) and corresponding HPO release. However, the relevance of reductive dissolution of Fe(III)-P for plant and microbial P uptake is still an open question.