J 2003

Sensitivity of photosystem 2 of Antarctic lichens to high irradiance stress:Fluorometric study of fruticose (Usnea antarctica)and foliose (Umbilicaria decussata) species

BARTÁK, Miloš, Hana VRÁBLÍKOVÁ a Josef HÁJEK

Základní údaje

Originální název

Sensitivity of photosystem 2 of Antarctic lichens to high irradiance stress:Fluorometric study of fruticose (Usnea antarctica)and foliose (Umbilicaria decussata) species

Název anglicky

Sensitivity of photosystem 2 of Antarctic lichens to high irradiance stress:Fluorometric study of fruticose (Usnea antarctica)and foliose (Umbilicaria decussata) species

Autoři

BARTÁK, Miloš (203 Česká republika, garant), Hana VRÁBLÍKOVÁ (203 Česká republika) a Josef HÁJEK (203 Česká republika)

Vydání

Photosynthetica, Praha, Elsevier, 2003, 0300-3604

Další údaje

Jazyk

čeština

Typ výsledku

Článek v odborném periodiku

Obor

10600 1.6 Biological sciences

Stát vydavatele

Česká republika

Utajení

není předmětem státního či obchodního tajemství

Impakt faktor

Impact factor: 0.661

Kód RIV

RIV/00216224:14310/03:00008618

Organizační jednotka

Přírodovědecká fakulta

Klíčová slova anglicky

chlorophyll fluorescence; low temperature; photoinhibition; photosynthesis; non-photochemical quenching; recovery.
Změněno: 23. 4. 2004 10:12, prof. Ing. Miloš Barták, CSc.

Anotace

V originále

Two lichen species collected in maritime Antarctica (King George Island) were exposed under laboratory conditions to excess irradiance to evaluate the response of photosystem 2 (PS2). The response was measured on fully hydrated lichen thalli at 5 oC by means of a modulated fluorometer using chlorophyll (Chl) fluorescence induction curve supplemented with analysis of quenching mechanisms. Chl fluorescence parameters [i.e. ratio of variable to maximum Chl fluorescence (FV/FM), quantum yield of PS2 photochemical reactions (?2), quenching coefficients] were evaluated before and several times after exposition to high irradiance in order to characterise the extent of photoinhibition, fast and slow phase of recovery. Strong irradiance (2 000 ľmol m-2 s-1) caused high degree of photoinhibition, particularly higher in fruticose (Usnea antarctica) than in foliose (Umbilicaria decussata) lichen species. Fast phase of recovery from photoinhibition, corresponding to regulatory mechanisms of PS2, was apparent in both species for FV/FM and ?2 within 40 min after photoinhibitory treatment. It was followed by a slow phase lasting several hours, corresponding to repair and re-synthesis processes. After photoinhibitory treatment, recovery of non-photochemical quenching (NPQ) was faster and more pronounced in U. decussata than in U. antarctica. Significant differences were found between the two species in the rate of recovery in fast- (qE) and slow-recovering (qT+I) component of NPQ.

Anglicky

Two lichen species collected in maritime Antarctica (King George Island) were exposed under laboratory conditions to excess irradiance to evaluate the response of photosystem 2 (PS2). The response was measured on fully hydrated lichen thalli at 5 oC by means of a modulated fluorometer using chlorophyll (Chl) fluorescence induction curve supplemented with analysis of quenching mechanisms. Chl fluorescence parameters [i.e. ratio of variable to maximum Chl fluorescence (FV/FM), quantum yield of PS2 photochemical reactions (?2), quenching coefficients] were evaluated before and several times after exposition to high irradiance in order to characterise the extent of photoinhibition, fast and slow phase of recovery. Strong irradiance (2 000 ľmol m-2 s-1) caused high degree of photoinhibition, particularly higher in fruticose (Usnea antarctica) than in foliose (Umbilicaria decussata) lichen species. Fast phase of recovery from photoinhibition, corresponding to regulatory mechanisms of PS2, was apparent in both species for FV/FM and ?2 within 40 min after photoinhibitory treatment. It was followed by a slow phase lasting several hours, corresponding to repair and re-synthesis processes. After photoinhibitory treatment, recovery of non-photochemical quenching (NPQ) was faster and more pronounced in U. decussata than in U. antarctica. Significant differences were found between the two species in the rate of recovery in fast- (qE) and slow-recovering (qT+I) component of NPQ.

Návaznosti

GA522/03/0754, projekt VaV
Název: Fotoinhibice a fotoochrana u lišejníků v extrémních podmínkách
Investor: Grantová agentura ČR, Fotoinhibice a fotoochrana u lišejníků v extrémních podmínkách
MSM 143100007, záměr
Název: Ekologie pobřežní antarktické vegetační oázy
Investor: Ministerstvo školství, mládeže a tělovýchovy ČR, Ekologie pobřežní antarktické vegetační oázy