3,4-Dimethylpyrazole (phosphate) (3,4-DMPP) is an inhibitor of nitrification deemed safe by extensive standard toxicology and ecotoxicology tests.
1 When utilized on crops, 3,4-DMPP prevents nitrogen loss from soil, increases nitrogen use efficiency, and boosts crop yields.
1,2 However, a meta-analysis found no influence of 3,4-DMPP on net crop yield, although it may boost yields in alkaline soil.
3 3,4-DMPP may be less effective in acidic soils and in the post-harvest period.
4,5 DMPP interferes with ammonia monooxygenase from ammonia-oxidizing bacteria (AOB) and archaea (AOA) but may not directly affect AOB, AOA, and non-target populations.
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