Glycerophosphodiester Phosphodiesterase ZmGPX-PDE1 Regulates Phosphorus Remobilisation and JA-Mediated Anther Development in Maize.

Phosphorus (P) is essential for plant growth, yet its limited availability necessitates efficient utilisation, especially during reproductive stages where P remobilisation mechanisms are not fully understood. This study investigates the role of the maize gene ZmGPX-PDE1, which encodes a glycerophosphodiester phosphodiesterase involved in phospholipid metabolism by hydrolysing glycerophosphodiesters to glycerol-3-phosphate, regulates P remobilisation and reproductive development. Using loss-of-function mutants and overexpression lines, we demonstrated that ZmGPX-PDE1 facilitates the redistribution of P from vegetative tissues to reproductive organs, thereby enhancing biomass accumulation, grain yield, and pollen viability under low-P conditions. Furthermore, our results reveal that ZmGPX-PDE1 influences jasmonic acid (JA) signalling, a critical pathway for anther dehiscence and male fertility. Loss of ZmGPX-PDE1 function results in impaired P remobilisation, reduced anther P content, and disrupted JA signalling, leading to decreased pollen quality and yield. These findings provide new insights into the molecular mechanisms underlying P homeostasis in maize and highlight ZmGPX-PDE1 as a promising target for developing P-efficient cultivars suitable for sustainable agriculture.