The geographical variation of stomatal traits indicates the invasion strategy of Solanum rostratum (Solanaceae) in northern China

Background and Aims Stomatal trait variation influences plant functions and reflects environmental adaptation. Biological invasions are increasing, affecting biodiversity and ecosystems. Solanum rostratum Dunal has extensively invaded northern China, causing significant damage to local ecosystem stability. Determining plant stomatal trait variation in heterogeneous habitats is crucial for revealing the adaptive capacity of invasive plants and their strategies for coping with environmental changes. Methods We collected leaf samples from four S. rostratum populations in distinct habitats and climatic zones, measured inter-population variations in stomatal traits to determine how leaf stomatal characteristics vary in response to heterogeneous environmental conditions. Results In extremely arid regions, S. rostratum adopted an opportunistic investment strategy, maximizing the metabolic cost reduction and maintaining the guard cell respiration rate. Under optimal water and heat conditions, S. rostratum developed numerous small stomata across the leaf surface, achieving a large stomatal pore size and high stomatal conductance, which maximized growth through a rapid resource acquisition strategy. Conclusions S. rostratum is a shrewd invasive plant that balances stomatal control strategies by regulating stomatal traits in highly heterogeneous habitats. In extremely arid distribution areas, S. rostratum adopting opportunistic investment strategies. When the water and heat conditions reach the ideal state, small and dense stomata are distributed on the S. rostratum leaf surface, promoting maximum plant growth, and adopting a rapid resource acquisition strategy. The high plasticity of stomatal traits under heterogeneous habitats contributes to the successful invasion of S. rostratum .