Chloroplast pigment photobleaching and its effect on low temperature fluorescence spectra of chlorophyll in greening cucumber cotyledons

Title:

Chloroplast pigment photobleaching and its effect on low temperature fluorescence spectra of chlorophyll in greening cucumber cotyledons

Creator:

Wieckowski, S. and Waloszek, A.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:f7ee4e98-ff72-4128-a28d-44f2303d1050
uuid:f7ee4e98-ff72-4128-a28d-44f2303d1050
urnnbn:urn:nbn:cz:aba007-000fih

Type:

model:internalpart and TEXT

Format:

print

Description:

Effects of high irradiance (HI) treatment on chloroplast pigment bleaching and on low temperature excitation and emission fluorescence spectra were studied in thylakoids isolated from 3- or 24-h greening cucumber cotyledons of etiolated seedlings. Irradiation of thylakoids isolated from 3-h greening seedlings with HI (approx. 3500 pmol m'^ s'*) caused chlorophyll (Chl) and carotenoid (Car) breakdown with the initial rates 3.0 and 4.2 mg m’^ s'*, respectively, whereas these values were 1.3 and 0.8 mg m-^ s'^ respectively, in thylakoids isolated from 24-h greening cotyledons. The photosusceptibility decreased in the sequence: protochlorophyll(ide), P-carotene, xanthophylls, Chl a, Chl b. In control seedlings the ratio E472/E437 or E486/E437 was 1.7-1.8-fold higher at the later phase than at the early phase of greening whereas the ratio F730/F684 reached approx. 0.40 or approx. 1.65 after 3- or 24-h greemng, respectively. Treatment of isolated thylakoids with high photon flux density caused a relative increase of the 472 and 486 nm band intensities in the excitation fluorescence spectrum of Chl, whereas the ratio F730/F684 increased only at the later phase investigated.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

509-520 and 31-42

Source:

Photosynthetica | 1993 Volume:29 | Number:4

Harvested from:

CDK

Metadata only:

false