关键词: 中华金叶榆；无性系；光合特性；叶绿素荧光参数；日变化

Abstract:

In order to study the differences in character and photosynthetic among the different clones, and then develop excellent clone, the 3 years grafted seedlings of different clones selected and developed from the generation of Golden Ulmus pumila were used as materials and female parent Ulmus pumila cv. ‘Zhonghua jinye’ as control. The morphologyical characteristics and the diurnal variations of photosynthetic and fluorescence paramaters were studied. The results showed that there were significant differences on morphologyical characteristics among different clones and control. The diurnal variation of net photosynthetic rate (Pn), transpiration rate (Tr), stomata conductance (Gs) and internal cellular CO2 concentration (Ci) were different. The mean net photosynthetic rate of one day from big to small was clone C (12.35μmol/m2·s） > control（11.99μmol/m2·s）> clone B（11.98μmol/m2·s）> clone A（1080 μmol/m2·s）,which explained that the clone C developed quickly and clone A slowly on theory. There were differences on diurnal variation of Fo, Fm and Fv/Fm among different clones and control. The values of both Fm and Fv/Fm drop first and then rose again, indicating that photosynthetic activity was only temporarily inhibited while the photosynthetic organs were not damaged.  The ability of tolerant to photoinhibition of the different clones was different. Clone A was strongest inhibited and clone C was inhibited most lightly.

Key words: Ulmus pumila cv. ‘Zhonghua jinye’, clone, photosynthesis characteristics, chlorophyll fluorescence parameters, diurnal variation