摘要 : The interactive effects of light intensity and controlled-release nitrogen fertilizer (CRNF) supply on growth, gas exchange, and chlorophyll (Chl) fluorescence parameters of two species of potted <i>Hosta</i> seedlings, original s... 展开 The interactive effects of light intensity and controlled-release nitrogen fertilizer (CRNF) supply on growth, gas exchange, and chlorophyll (Chl) fluorescence parameters of two species of potted <i>Hosta</i> seedlings, original species of the genus <i>Hosta</i> in China, were studied. N₄ (4 g of CRNF per pot), N₈ (8 g of CRNF per pot), and sometimes N₁₂ (12 g of CRNF per pot), significantly increased total dry weights, net photosynthetic rate (<i>P</i>_N), stomatal conductance (<i>g</i>_s), transpiration rate (<i>E</i>), the maximum quantum yield of PSII photochemistry (<i>F</i>_v/<i>F</i>_m), the maximum ratio of quantum yields of photochemical and concurrent nonphotochemical processes in PSII (<i>F</i>_v/<i>F</i>₀), actual efficiency of photochemical energy conversion in PSII under light ( Phi _PSII), and photochemical quenching coefficient (qP), but significantly decreased internal CO₂ concentration (<i>C</i>_i) and nonphotochemical Chl fluorescence quenching (NPQ) compared to control plants at different growth stages of the two <i>Hosta</i> species in two levels of light intensities (50% of natural light (L₅₀) and 70% of natural light (L₇₀)). Based on the available data, we concluded that the increments in total dry weights of <i>Hosta clausa</i> var. <i>ensata</i> and <i>Hosta ventricosa</i> by appropriate amount of CRNF supply treatments under L₅₀ and/or L₇₀ light conditions are directly related to the increments in the <i>P</i>_N, which may be due to both stomatal and nonstomatal improvements for a longer growing time. Furthermore, there was an interaction between light intensity and CRNF supply treatments on growth and photosynthetic characteristics of the two <i>Hosta</i> species. The adaptability of <i>Hosta</i> plants with obvious stoloniferous rootstock to stronger light was higher than that of <i>Hosta</i> plants without obvious stoloniferous rootstock. 收起