不同光照条件对兴安杜鹃和迎红杜鹃光合生理的影响

Effects of Different Light Conditions on Physioecological Characteristics of Rhododendron dauricum and Rhododendron mucronulatum

通过对全光照、半光照和遮荫处理的兴安杜鹃和迎红杜鹃进行光合生理指标研究。结果表明:光照条件对兴安杜鹃和迎红杜鹃的光合作用影响显著,而对呼吸作用影响不显著,光合作用和呼吸作用对光环境变化的反映是独立的;在光照处理中半光条件下兴安杜鹃和迎红杜鹃生长状态最好;在全光照条件下迎红杜鹃的光合速率、蒸腾速率和呼吸速率都高于兴安杜鹃;在半光条件下迎红杜鹃气孔导度和胞间CO2体积分数高于全光照和遮荫处理;兴安杜鹃和迎红杜鹃在栽培应用上注意光照条件,采取乔灌混栽效果更佳。

Rhododendron dauricum L. and Rhododendron mucronulatum Turez. were cultivated under three light regimes （ 100% light, 50% light, and shading） to examine the photosynthetic parameters. Light intensity significantly affected the photosynthesis of R. dauricum and R. mucronulatum, but there was no significant effect on the respiration of the two species. The responses of photosynthesis and respiration to light conditions were independently. R. dauricum and R. mucronulatum grew well under 50% light. R. mucronulatum had higher photosynthesis rate, respiratory rate, and transpiration rate under different treatments compared with R. dauricum. R. mucronulatum had higher stomatal conductance and intercellular CO2 concentration under 50% light condition compared with other treatments. Light condition is an important factor for cultivation of the two Rhododendron species. The better site to plant them is under arbor trees.