Biological Effects of FeP Nanoparticles on Symbiotic Nitrogen Fixation Capacity of Soybean Seedlings

Iron phosphide nanoparticles (FeP NPs) are a type of nano-transition metal phosphide that plays a significant role in nitrogen uptake and assimilation in soybeans because they contain essential plant nutrients, such as phosphorus and iron. The characteristics of nanomaterials, including high electrochemical activity, good thermal stability, and multiple active sites, make FeP NPs a promising candidate for application as a new type of nano fertilizer in agriculture. Herein, the effects of FeP NPs and traditional phosphorus and iron fertilizers on plant phenotypes, antioxidant systems, and nitrogen metabolism-related indexes of soybean seedlings were compared. Notably, 50 mg L–1 FeP NPs promoted soybean growth and symbiotic nitrogen fixation more effectively than traditional phosphorus and iron fertilizer treatments by regulating reactive oxygen metabolism, enhancing the GS-GOGAT cycle, and increasing nitrogen content. This study demonstrates the potential use of FeP NPs as a new approach for fertilizer application in agriculture.