Phosphorus nutrition modulates DEHP uptake, translocation, and metabolism in tomato seedlings

Di (2-ethylhexyl) phthalate (DEHP) is an endocrine disruptor, and its residual levels in farmlands are increasing with the widespread usage of greenhouses, pesticides, and fertilizers. Tomato, a widely grown vegetable in greenhouses, was selected as a representative of plants to investigate the influence mechanisms of phosphorus nutrition on DEHP residues. The results showed that DEHP residual levels were significantly negatively correlated with phosphorus contents. The absorption pathways experiment indicated that the absorption of DEHP in the tomato seedlings required the mediation of H⁺-ATPase and ABC transporters. Phosphorus nutrition reduced the absorption and transportation of DEHP by reducing H⁺-ATPase activity and ABC transporter content, and enhanced the metabolism of DEHP in the tomato seedlings by increasing carboxylesterase activity. Transcriptomic analysis revealed that the reduction in ABC transporter content resulted from the downregulation of the expression of ABC transporter B family members (gene-LOC101263029), thereby reducing the transportation of DEHP from roots to shoots. At the same time, sufficient phosphorus nutrition enhanced the TCA cycle and increased redox equivalents, leading to promote the metabolism of DEHP in the tomato seedlings. These findings provided a mechanistic basis for using phosphorus fertilizer to reduce plasticizer pollution in greenhouse-grown plants.