血红鸡爪槭的光合特性研究

目的]研究血红鸡瓜槭（Acer palmatum‘Bloodgood’）的光合特性,为提高其光能利用率和转化效率,进而提高其园林观赏价值提供参考。方法]选取天病虫害、长势基本一致的血红鸡爪槭1年生苗为供试材料,利用Li-6400便携式光合作用测定系统测定其光合特性。结果]血红鸡爪槭光补偿点、光饱和点和CO2补偿点、CO2饱和点分别为1 260、32.66μmol/（m2.s）和49.34、991.67μmol/mol,且最适宜在25～27℃温度范围内生长;叶片净光合速率（Pn）在夏季呈典型的双峰曲线,有明显的＂光合午休＂现象,且光合有效辐射（PAR）、气孔导度（Gs）、蒸腾速率（Tr）分别是影响叶片净光合速率最重要的环境因子和生理因子;高温胁迫下叶片PSⅡ的活性受到了抑制,光化学反应的份额减少,非光化学反应的份额增加。结论]该研究揭示了血红鸡爪槭光合特性的基本变化规律及限制其光合作用的内外因子,可为今后其更好的应用提供指导。

Photosynthetic Characteristics of Acer palmatum 'Bloodgood'

Objective] The photosynthetic characteristics of Acer palmatum 'Bloodgood' were studied to improve the utilization percentage and transformation efficiency of light energy and to provide reference for improve its ornamental value of its garden.Method] Selecting the Acer palmatum 'Bloodgood' of no disease and same growth as materials,it was found that the light compensation and saturated points were 32.66 μmol/(m2·s) and 1 260 μmol/(m2·s) respectively,the CO2 compensate and saturated points were 49.34 μmol/(m2·s) and 991.67 μmol/(m2·s) respectively,and the optimum temperature was between 25 ℃ and 27 ℃;the photosynthetic rate presented a typical double peak curve in summer;an obvious phenomenon of "mid-day depression" occurred,and in the whole growing season,PAR、Gs and Tr were the most significant environmental and physiological factors influencing Pn of the leaves;high temperature stress reduced photochemical quenching and increased Non-photochemical quenching.Conclusion] The study indicated the basic changes of the photosynthetic characteristics of Acer palmatum 'Bloodgood' and restricted the internal and external factors of photosynthesis and provided references to better application.