Aerated Drip Irrigation Enhances Soil Phosphorus Activation and Use Efficiency in Greenhouse Tomatoes

Background : Low phosphorus (P) use efficiency and rhizosphere hypoxia limit crop performance in intensive greenhouse production systems. Aims : This study aimed to examine whether aerated drip irrigation (ADI) enhances soil P activation and plant P uptake by regulating P fractions, enzymatic activities, root traits, and root exudates under varying P inputs. Methods : A factorial design experiment combining two irrigation modes (ADI and conventional drip irrigation [CDI]) with three P levels (0, 75, and 150 kg ha −1 ) was conducted. Soil P fractions, acid phosphatase (ACP) activity, root morphology, and root exudate metabolomics were analyzed. Results : Compared with CDI, ADI decreased soil organic P and increased labile P fractions, and particularly under the 75 kg ha −1 P (P 1 ) rate, ACP increased activity by up to 56.5%. The ADI under P 1 significantly improved root morphology, such as root length and tip number by 18.3% and 37.4%, respectively. Simultaneously, ADI significantly upregulated the exudation of P‐mobilizing metabolites (e.g., phenolic acids, sphingosine). Consequently, ADI under P 1 enhanced yield (12.7%) and P use efficiency (12.7%). Conclusions : ADI successfully enhances P activation and utilization by elevating ACP activity, optimizing root foraging traits, and shifting exudate profiles. Combining ADI with a moderate P input maximizes productivity, offering a sustainable strategy to reduce fertilizer reliance.