Temperature sensitivity of photosystem II in isolated thylakoid membranes from fluridone-treated pea leaves

Authors : Kolyo DANKOV, Georgi RASHKOV, Amarendra MISRA, Emilia L APOSTOLOVA

Pages : 420-428

Doi:10.3906/bot-1407-46

View : 17 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :High temperature-induced changes in the photosystem II insert ignore into journalissuearticles values(PSII); activity of thylakoid membranes isolated from pea insert ignore into journalissuearticles values(Pisum sativum L. `Ran`); plants treated with low insert ignore into journalissuearticles values(10-8 M); and high insert ignore into journalissuearticles values(10-7 M); concentrations of fluridone were investigated. Pulse amplitude modulated insert ignore into journalissuearticles values(PAM); chlorophyll fluorescence and photosynthetic oxygen evolution insert ignore into journalissuearticles values(measured by polarographic oxygen rate electrode); were used to estimate the effect of high temperature on the functional activity of PSII. Higher temperature treatments lead to stronger inhibition of the flash oxygen evolution than the primary photochemistry of PSII insert ignore into journalissuearticles values(Fv/Fm);. The inhibitory effect of higher temperature on the PSII? centers is stronger than on the PSIIß centers. The heat-induced damage in the PSII$\alpha$ centers as well as in the donor side of all PSII centers insert ignore into journalissuearticles values(PSII$\alpha$ and PSIIß); is accentuated by fluridone.
Keywords : Fluridone, PAM chlorophyll fluorescence, photosynthetic oxygen evolution, PSII centers, PSIIß centers, carotenoids