The strategies for improving phosphorus-use efficiency in plant cell

Phosphorus (P) is an essential macronutrient for plant growth and development, but P deficiency is a key limiting factor for crops growth and yield. To cope with P deficiency, plants have evolved many adaptive strategies. In this review, we focused on the mechanism of improving P-use efficiency (PUE). We discussed the main adaptive strategies in plant cell: Pi redistribution between cell compartments, Pi release from organic phosphorus (Po), and Pi-saving metabolic routes. Pi transporters at the tonoplast or membrane system are engaged in the exchange of Pi. The Po pools contain RNA, Pi-monoesters, phytate, and phospholipids. The hydrolases [RNase, APase (Acid phosphatase), Phytase, and Phospholipase] are involved in the Pi release from the Po compounds. Under long-term P deficiency, Pi-independent metabolic processes are triggered to maintain cell activity, such as PPi-dependent alternative metabolic pathway and mitochondrial electron transport. Understanding of the mechanisms of internal PUE would help to develop P utilization efficient plants.