Role of Silicon in Mediating Phosphorus Imbalance in Plants

• Main Authors: An Yong Hu, Shu Nan Xu, Dong Ni Qin, Wen Li, Xue Qiang Zhao
• Format: Article
• Language: English
• Published: MDPI AG 2021-12-01
• Series: Plants
• Subjects: silicon; silicon transporter; phosphorus transporter; phosphorus imbalance; phosphorus deficiency; excess phosphorus
• Online Access: https://www.mdpi.com/2223-7747/10/1/51

The soil bioavailability of phosphorus (P) is often low because of its poor solubility, strong sorption and slow diffusion in most soils; however, stress due to excess soil P can occur in greenhouse production systems subjected to high levels of P fertilizer. Silicon (Si) is a beneficial element that can alleviate multiple biotic and abiotic stresses. Although numerous studies have investigated the effects of Si on P nutrition, a comprehensive review has not been published. Accordingly, here we review: (1) the Si uptake, transport and accumulation in various plant species; (2) the roles of phosphate transporters in P acquisition, mobilization, re-utilization and homeostasis; (3) the beneficial role of Si in improving P nutrition under P deficiency; and (4) the regulatory function of Si in decreasing P uptake under excess P. The results of the reviewed studies suggest the important role of Si in mediating P imbalance in plants. We also present a schematic model to explain underlying mechanisms responsible for the beneficial impact of Si on plant adaption to P-imbalance stress. Finally, we highlight the importance of future investigations aimed at revealing the role of Si in regulating P imbalance in plants, both at deeper molecular and broader field levels.