Strong phosphorus (P)-zinc (Zn) interactions in a calcareous soil-alfalfa system suggest that rational P fertilization should be considered for Zn biofortification on Zn-deficient soils and phytoremediation of Zn-contaminated soils

• Published in: Plant and soil Vol. 461; no. 1/2; pp. 119 - 135
• Main Authors: He, Honghua, Wu, Miaomiao, Su, Rui, Zhang, Zekun, Chang, Chao, Peng, Qi, Dong, Zhigang, Pang, Jiayin, Lambers, Hans
• Format: Journal Article
• Language: English
• Published: Cham Springer Science + Business Media 01.04.2021; Springer International Publishing; Springer Nature B.V
• Subjects: Accumulation; Agriculture; Alfalfa; Bioavailability; biofortification; Biomedical and Life Sciences; Calcareous soils; Carboxylates; Chemical partition; citrates; Citric acid; Ecology; Exudation; Fertilization; Life Sciences; Malate; malates; Nutrient deficiency; Partitioning; pH effects; Phosphorus; Phytoremediation; Plant extracts; Plant growth; Plant Physiology; Plant Sciences; Regular Article; REGULAR ARTICLES; Shoots; Soil contamination; Soil investigations; Soil pollution; Soil Science & Conservation; Soils; Zinc; DTPA-extractable Zn; Partitioning; Rhizosheath carboxylates; Rhizosheath pH
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-020-04793-w

Aims Zinc (Zn) and phosphorus (P) often interact negatively with each other in soil-plant systems. We investigated the effects of P-Zn interaction on Zn and P accumulation and partitioning in alfalfa. Methods Plants were grown in a calcareous soil supplied with different rates of Zn (0, 200, and 800 mg kg −1 ) and P (0, 20, and 80 mg kg −1 ). Plant dry mass, Zn and P concentrations in shoots and roots, bulk soil and rhizosheath pH, rhizosheath carboxylates, and DTPA-extractable Zn concentration in the bulk soil were determined. Results Phosphorus-Zn interaction significantly affected DTPA-extractable Zn concentration, plant dry mass, accumulation of Zn and P, and partitioning of Zn in alfalfa, but did not affect rhizosheath pH or the amounts of rhizosheath carboxylates. Increasing P rate promoted plant growth at all soil Zn rates and might enhance the plants’ capacity to cope with excessive Zn; it resulted in a lower rhizosheath pH, which likely contributed to greater Zn and P uptake. Zinc deficiency enhanced exudation of citrate, malonate and malate, while the release of tartrate was related with P deficiency. Conclusions There are strong P-Zn interactions in calcareous soil-plant system, such interactions significantly affect Zn bioavailability, plant growth, accumulation of Zn and P, and partitioning of Zn in alfalfa. Rational P fertilization should be considered for efficient Zn biofortification on Zn-deficient soils and phytoremediation of Zn-contaminated soils.