Integrating RNA-Seq and Metabolomic Perspectives Reveals the Mechanism of Response to Phosphorus Stress of Potamogeton wrightii

Phosphorus is an important nutrient element in aquatic ecosystems, and its concentration directly affects the growth and ecological functions of submerged plants. However, the physiological and molecular mechanisms of P. wrightii’s response to phosphorus stress remain unknown. This study investigated the effects of different phosphorus concentration treatments on P. wrightii through physiological, RNA-seq, and metabolome analysis methods. The results indicated that phosphorus stress affected plant physiology by reducing chlorophyll content, increasing MDA and H2O2 accumulation, and activating the antioxidant enzyme system. Multiple phosphorus transporters (PHT, SPX, and PAP) and the transcription factor PHR1 were identified through RNA-seq and RT-qPCR analysis. The glycerol phospholipids represent a decreasing trend after low or high phosphorus stress. Through the combined analysis of RNA-seq and metabolome analysis, the response differences of 6 DAMs and 19 DEGs to the P. wrightii Glycerolipid metabolism and Glycerophospholipid metabolism pathways under different phosphorus stresses were revealed. Our results provide a scientific basis and guidance for restoring submerged plants in shallow lakes and for preventing and controlling eutrophication.