English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The stability of PSII in leaves of the resurrection plant Haberlea rhodopensis to high temperature and high light intensities was studied by means of chlorophyll fluorescence measurements. The photochemical efficiency of PSII in well-hydrated Haberlea leaves was not significantly influenced by temperatures up to 40 °C. F 0  reached a maximum at 50 °C, which is connected with blocking of electron transport in reaction center II. The intrinsic efficiency of PSII photochemistry, monitored as F v /F m  was less vulnerable to heat stress than the quantum yield of PSII electron transport under illumination (ΦPSII). The reduction of ΦPSII values was mainly due to a decrease in the proportion of open PSII centers (qP). Haberlea rhodopensis was very sensitive to photoinhibition. The light intensity of 120 μmol m −2  s −1  sharply decreased the quantum yield of PSII photochemistry and it was almost fully inhibited at 350 μmol m −2  s −1 . As could be expected decreased photochemical efficiency of PSII was accompanied by increased proportion of thermal energy dissipation, which is considered as a protective effect regulating the light energy distribution in PSII. When differentiating between the three components of qN it was evident that the energy-dependent quenching, qE, was prevailing over photoinhibitory quenching, qI, and the quenching related to state 1-state 2 transitions, qT, at all light intensities at 25 °C. However, the qE values declined with increasing temperature and light intensities. The qI was higher than qE at 40 °C and it was the major part of qN at 45 °C, indicating a progressing photoinhibition of the photosynthetic apparatus.

Thermostability and Photostability of Photosystem II of the Resurrection Plant Haberlea rhodopensis Studied by Chlorophyll Fluorescence