关键词: 香樟, 指数施肥, 光合生理特性, 光响应曲线

Abstract: [Objective] The objective of this study was to investigate the effects of fertilization on photosynthetic physiology of camphor (Cinnamomum camphora (L.) Presl) seedlings.[Method] Orthogonal design with three factors including N,P,K nutrients at three levels (N,P:0,3,6 g/pot;K:0,2,4 g/pot) was used to conduct pots experiments under exponential fertilization.[Results] The nitrogen fertilizer could improve the net photosynthetic rate (P_n),chlorophyll content (Chl) and intercellular CO₂ concentration (C_i) of seedlings.The P_n and Chl increased firstly and then decreased by the increase of nitrogen application.Its maximum is at level of 3 g/pot nitrogen application.The positive correlation existed between C_i and nitrogen application.The phosphorus fertilizer could improve the light saturation point (LSP) of seedlings.The LSP increased by the increase of phosphorus application.Its maximum is at level of 6 g/pot phosphorus application.The potash fertilizer could reduce the transpiration rate (T_r) of seedlings.The T_r decreased firstly and then increased by the increase of potash.Its minimum is at level of 2 g/pot potash application.[Conclusion] The results indicated that the fertilization could improve the photosynthetic efficiency of camphor seedlings.The most appropriate nitrogen,phosphorus and potassium ratio for photosynthetic efficiency of seedlings is N2:P3:K1=3:6:0.

Key words: Cinnamomum camphora (L.) Presl, exponential fertilization, photosynthetic characteristics, light response curve