Titre :

Light response curve methodology and possible implications in the 2 application of chlorophyll fluorescence to benthic diatoms

Auteur(s) :

Perkins, Rupert G. [Auteur correspondant]
School of Earth and Ocean Sciences [Cardiff]
Mouget, Jean-Luc [Auteur]
Laboratoire de Physiologie et Biochimie Végétales
Lefebvre, Sébastien [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Lavaud, Johann [Auteur]
Centre National de la Recherche Scientifique [CNRS]
LIttoral ENvironnement et Sociétés [LIENSs]

Titre de la revue :

Marine Biology

Pagination :

703-712

Éditeur :

Springer Verlag

Date de publication :

2006-07-01

ISSN :

0025-3162

Mot(s)-clé(s) en anglais :

Light Curf
Electron Transport Rate
Benthic Diatom
Light Dose
Light Response Curve

Discipline(s) HAL :

Sciences du Vivant [q-bio]/Biologie végétale

Résumé en anglais : [en]

Chlorophyll a fluorescence has been increasingly applied to benthic microalgae, especially diatoms, for measurements of electron transport rate (ETR) and construction of rapid light response curves (RLCs) for the determination ...
Lire la suite >Chlorophyll a fluorescence has been increasingly applied to benthic microalgae, especially diatoms, for measurements of electron transport rate (ETR) and construction of rapid light response curves (RLCs) for the determination of photophysiological parameters [mainly the maximum relative ETR (rETRmax), the light saturation coefficient (E k) and the maximum light use coefficient (α)]. Various problems with the estimation of ETR from the microphytobenthos have been identified, especially in situ. This study further examined the effects of light history of the cells and light dose accumulation during RLCs on the fluorescence measurements of ETR using the benthic diatom Navicula phyllepta. RLCs failed to saturate when using incremental increases in irradiance, however, curves with decreasing irradiance did saturate. Patterns indicating photoacclimation in response to light histories were observed, with higher rETRmax and E k, and lower α, at high light compared to low light. However, these differences could be negated by increasing the RLC irradiance duration from 30 to 60 s. It is suggested that problems arose as a result of rapid fluorescence variations due to ubiquinone (QA) oxidation and non-photochemical chlorophyll fluorescence quenching (NPQ) which depended upon the light history of the cells and the RLCs accumulated light dose. Also, RLCs with irradiance duration of 10 s were shown to have a high level of error possibly specific to the fluorimeter programming. It is suggested that RLCs, using a Diving-PAM fluorimeter on benthic diatoms, should be run using decreasing irradiance steps of 30 s duration.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL