安徽农业科学2011，Vol.39Issue(9)：5069-5072,4.
增强UV-B辐射和Cd2+复合胁迫下绿豆幼苗Cd积累和光合作用的气孔和非气孔限制
Stomatal and Nonstomatal Limitations of Photosynthesis in P. radiatus L. Seedling Leaves under the Combination of Enhanced UVB Radiation and Cd2+ Stress
摘要
Abstract
[ Objective ] The research aimed to study the stomatal and nonstomatal limitations of photosynthesis in P. radiatus L. seedling leaves under the combination of enhanced UV-B radiation and Cd2+ stress. [ Method] The test designed one control group and 3 test groups, enhanced UV-B radiation(UV-B) group, Cd2+ (Cd) group and enhanced UV-B radiation + Cd2+ (UV-B + Cd) group respectively. Stomatl and nonstomatal limitations of photosynthesis in P. radiatus L. seedling leaves under the combination of 0.35 W/m2 UV-B radiation and 1 μmol/L Cd2+ stress were studied. Cd concentration in root, hypocotyls, and leaf were determined by atomic absorption spectrometer, respectively. The photnsynthetic parameters of the first pair leaves of P. radiatus L. seeding were monitored by TPS-1 photosynthesis system or calculated according to the theory of Farquhar and Sharkey. [Result] Cd concentration allocated in different parts of P. radiatus L. was root ＞ hypocotyl ＞ leaf,and UV-B group had no effect on the absorption and allocation in P. radiatus L.. In addition, separated or combined treatments of enhanced UV-B radiation and Cd2 + stress all resulted in a decrease in net photosynthetic rate, stomatal conductance, photosynthetic ability, efficiency of CO2 carboxylafion and rubisco content. That intercellular CO2 concentration increased and stomatal limitation value decreased under UV-B treatment indicated that the inhibition of photosynthesis in P. radiatus L. seedling leaves was nonstomatal limitation. That intercellular CO2 concentration decreased and stomatal limitation value increased under Cd treatment and combined treatment showed that the inhibition of photosynthesis in Cd treatment was stomatal limitation and the combined treatment was the results of stomatal and nonstomatal limination. [ Conclusion ] The study reveals the main factors of photosynthetic changes of P. radiatus L. seedling under the combination of enhanced UV-B radiation and Cd2+ stress, can provide the scientific basis for deeply research.关键词
绿豆幼苗/增强UV-B辐射/Cd2+胁迫/Cd积累/气孔限制/非气孔限制Key words
P. radiatus L. seedling/Enhancod UV-B radiation/Cd2+ stress/Cd accumulation/ Stomatal limitation/Nonstomatal limitation分类
农业科技引用本文复制引用
张媛华,王真,佘小平..增强UV-B辐射和Cd2+复合胁迫下绿豆幼苗Cd积累和光合作用的气孔和非气孔限制[J].安徽农业科学,2011,39(9):5069-5072,4.基金项目
陕西省教育厅自然科学专项(2010Jk536) （2010Jk536）
渭南师范学院科研项目(11YK2005). （11YK2005）
