Singlet oxygen, flavonols and photoinhibition in green and senescing silver birch leaves

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F86652079%3A_____%2F21%3A00553205" target="_blank" >RIV/86652079:_____/21:00553205 - isvavai.cz</a>

Výsledek na webu

<a href="https://link.springer.com/article/10.1007%2Fs00468-021-02114-x" target="_blank" >https://link.springer.com/article/10.1007%2Fs00468-021-02114-x</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00468-021-02114-x" target="_blank" >10.1007/s00468-021-02114-x</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Singlet oxygen, flavonols and photoinhibition in green and senescing silver birch leaves

Popis výsledku v původním jazyce

During autumn senescence, deciduous trees degrade chlorophyll and may synthesize flavonols. We measured photosynthetic parameters, epidermal flavonols, singlet oxygen production in vivo and photoinhibition of the photosystems (PSII and PSI) from green and senescing silver birch (Betula pendula) leaves. Chlorophyll a fluorescence and P-700 absorbance measurements showed that the amounts of both photosystems decreased throughout autumn senescence, but the remaining PSII units stayed functional until similar to 90% of leaf chlorophyll was degraded. An increase in the chlorophyll a to b ratio, a decrease in > 700 nm absorbance and a blue shift of the PSI fluorescence peak at 77 K suggest that light-harvesting complex I was first degraded during senescence, followed by light-harvesting complex II and finally the photosystems. Senescing leaves produced more singlet oxygen than green leaves, possibly because low light absorption by senescing leaves allows high flux of incident light per photosystem. Senescing leaves also induced less non-photochemical quenching, which may contribute to increased singlet oxygen production. Faster photoinhibition of both photosystems in senescing than in green leaves, under high light, was most probably caused by low absorption of light and rapid singlet oxygen production. However, senescing leaves maintained the capacity to recover from photoinhibition of PSII. Amounts of epidermal flavonols and singlet oxygen correlated neither in green nor in senescing leaves of silver birch. Moreover, Arabidopsis thaliana mutants, incapable of synthesizing flavonols, were not more susceptible to photoinhibition of PSII or PSI than wild type plants, screening of chlorophyll absorption by flavonols was, however, small in A. thaliana. These results suggest that flavonols do not protect against photoinhibition or singlet oxygen production in chloroplasts.

Název v anglickém jazyce

Singlet oxygen, flavonols and photoinhibition in green and senescing silver birch leaves

Popis výsledku anglicky

During autumn senescence, deciduous trees degrade chlorophyll and may synthesize flavonols. We measured photosynthetic parameters, epidermal flavonols, singlet oxygen production in vivo and photoinhibition of the photosystems (PSII and PSI) from green and senescing silver birch (Betula pendula) leaves. Chlorophyll a fluorescence and P-700 absorbance measurements showed that the amounts of both photosystems decreased throughout autumn senescence, but the remaining PSII units stayed functional until similar to 90% of leaf chlorophyll was degraded. An increase in the chlorophyll a to b ratio, a decrease in > 700 nm absorbance and a blue shift of the PSI fluorescence peak at 77 K suggest that light-harvesting complex I was first degraded during senescence, followed by light-harvesting complex II and finally the photosystems. Senescing leaves produced more singlet oxygen than green leaves, possibly because low light absorption by senescing leaves allows high flux of incident light per photosystem. Senescing leaves also induced less non-photochemical quenching, which may contribute to increased singlet oxygen production. Faster photoinhibition of both photosystems in senescing than in green leaves, under high light, was most probably caused by low absorption of light and rapid singlet oxygen production. However, senescing leaves maintained the capacity to recover from photoinhibition of PSII. Amounts of epidermal flavonols and singlet oxygen correlated neither in green nor in senescing leaves of silver birch. Moreover, Arabidopsis thaliana mutants, incapable of synthesizing flavonols, were not more susceptible to photoinhibition of PSII or PSI than wild type plants, screening of chlorophyll absorption by flavonols was, however, small in A. thaliana. These results suggest that flavonols do not protect against photoinhibition or singlet oxygen production in chloroplasts.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10611 - Plant sciences, botany

Projekt

<a href="/cs/project/EF16_019%2F0000797" target="_blank" >EF16_019/0000797: SustES - Adaptační strategie pro udržitelnost ekosystémových služeb a potravinové bezpečnosti v nepříznivých přírodních podmínkách</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Trees: structure and function

ISSN

0931-1890

e-ISSN

1432-2285

Svazek periodika

35

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

16

Strana od-do

1267-1282

Kód UT WoS článku

000629528300001

EID výsledku v databázi Scopus

2-s2.0-85102865890