Nanoparticle-enabled enhancement of plant photosynthesis: Mechanisms and applications

Enhancing photosynthesis, a fundamental process to convert light energy into chemical energy, is a frontier approach to increasing crop productivity. In recent years, nanoparticles (NPs) have emerged as promising tools to modulate photosynthetic performance, yet the mechanistic pathways connecting NP-plant interactions to photosynthetic responses remain unclear. Here, we provide an integrated synthesis of recent research on the impacts of NPs on photosynthesis from subcellular to whole plant level, an across-scale perspective that has been less systematically addressed in prior reviews. The effects of most investigated non-organic NP classes, including carbon-based such as carbon dots and carbon nanotubes and metal-based NPs such as SiO 2 , MoO 3 , ZnO, and Ag NPs are examined. Across both crop species such as lettuce and rice and model plants such as Arabidopsis and tobacco, we compare reported optimal concentrations (typically 10–100 mg/L) and emphasize the importance of appropriate controls, including untreated plants, bulk-material and ionic counterparts. Notably, this review delves into how NPs can enhance photosynthesis through both direct and indirect mechanism. It involves deeper consideration of how NPs influence light harvesting and photoconversion, excitation-energy regulation, electron transport, and thereby downstream impacts on CO 2 assimilation and the Calvin-Benson-Bassham (CBB) cycle. Common methods used to evaluate photosynthetic performance following NP treatments, as well as the relationship between NP uptake and their effects on photosynthesis, were also critically assessed. Overall, this review highlights how NP application and the rational design of targeted NP-based systems could improve photosynthesis and, in turn, enhance crop productivity and resilience under a changing climate. • Summarizes the NP impacts on photosynthesis and growth from subcellular to whole-plant scales. • Highlights direct and indirect mechanisms of NPs interaction photosynthetic machinery. • Discusses methods to evaluate photosynthesis after NP exposure and relates NP uptake to photosynthetic responses.