Effects of Exogenous Salicylic Acid on Photosynthesis in Arabidopsis Leaves Based on Fluorescence Spectra and Delayed Fluorescence Technique
CHEN Zhi-qiang1, 2, CHEN Wen-li1, 2*, YANG Cheng-wei1
1. College of Life Science, Guangdong Key Lab of Biotechnology for Plant Development，South China Normal University, Guangzhou 510631, China 2. MOE Key Laboratory of Laser Life Science, South China Normal University, Guangzhou 510631, China
Abstract：Salicylic acid plays an important role in the active oxygen metabolism and the photosynthesis of the plant. Wild type Arabidopsis thaliana (ecotype Columbia) and it’s two different mutants were used as experimental material: one is the cpr5 mutant which has an abundant endogenesis SA level under stress conditions, and the other is the eds-4 mutant which has a lacking endogenesis SA level under stress conditions. The leaves of those three different Arabidopsis were treated with 100, 300, and 500 μmol·L-1 concentrations of salicylic acid, respectively. The fluorescence emission spectra and the delayed fluorescence were detected respectively. The authors found that there was a slight elevation in the photosynthetic efficiency of PSⅡof the WT and eds-4 leaves with 100 and 300 μmol·L-1 SA treatment. However, there was a decrease in the photosynthetic efficiency and even a stress of the cpr5 leaves with 100 and 300 μmol·L-1 SA treatment. It was also showed that there came to be an obvious stress of the leaves of all three different kinds of Arabidopsis with 500 μmol·L-1 SA treatment and the photosynthetic efficiency of them decreases sharply. The generation of active oxygen was also detected with the DCF labeling under 500 μmol·L-1 SA treatment. The authors found that there was an obvious accumulation of active oxygen along with the time under SA treatment.
