High Temperature Effects on Light Sensitivity in the Two High Mountain Plant Species Soldanella alpina (L.) and Rannunculus glacialis (L.)

摘要: The susceptibility to high temperature-induced photoinhibition was investigated in leaves of two mountain plant species, S. alpina and R. glacialis. In both PSII similarly photoinactivated at 38degreesC the light. However, recovery from damage much faster depended on protein synthesis. contrast, independent synthesis Heat-induced photoinactivation species accompanied by: (1) a decrease relative photosynthetic electron transport rates, (2) an increase non-photochemical chlorophyll fluorescence quenching, (3) strong accumulation zeaxanthin, (4) marked soluble carbon metabolites (5) lipid metabolism products, which more pronounced glacialis than alpina. These results indicate that assimilation inhibited membranes were affected. Lipid peroxidation possible membrane disintegration might limit repair damaged glacialis, while appears be protected by carotenoids antioxidants. A alpha-tocopherol content reduced ascorbate indicated peroxide scavenging activity When zeaxanthin impaired DTT, increased And (x-tocopherol accumulated light-induced after growth mode rate temperature (Streb et al., 2003a) inability heat-induced distribution lower altitudes Alps.