Correlation between photoinhibition sensitivity and the rates and relative extents of xanthophyll cycle de-epoxidation in chlorina mutants of barley (Hordeum vulgare L.)

Title:

Correlation between photoinhibition sensitivity and the rates and relative extents of xanthophyll cycle de-epoxidation in chlorina mutants of barley (Hordeum vulgare L.)

Creator:

Peng, Chang-Lian, Duan, Jun, Lin, Guizhu, and Gilmore, A. M.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:eed12a10-1222-4f5f-a2f2-91bf0d623f5b
uuid:eed12a10-1222-4f5f-a2f2-91bf0d623f5b
issn:0300-3604
doi:10.1023/A:1024383431403

Subject:

antheraxanthin, chlorophyll a fluorescence, chlorosis, global kinetic analysis, non-photochemical quenching, photoprotection, violaxanthin, and zeaxanthin

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

We compared photoinhibition sensitivity to high irradiance (HI) in wild-type barley (wt) and both its chlorina f104-nuclear gene mutant, that restricts chlorophyll (Chl) a and Chl b synthesis, and its f2-nuclear gene mutant, that inhibits all Chl b synthesis. Both Fv/Fm and ΦPS2 decreased more significantly in f2 than f104 and wt with duration of HI exposure. Chl degraded more rapidly in the f2 than in either f104 or wt. Most sensitivity to photoinhibition was exhibited for f2, whereas there was little difference in response to HI between the f104 and wt. The highest de-epoxidation (DES) value at every time point of exposure to HI was measured for f2, whereas the wt had the lowest value among the three strains. There were two lifetime components resolved for the conversion of violaxanthin (V) to zeaxanthin plus antheraxanthin (Z + A). The most rapid lifetime was around 6 min and the slower lifetime was >140 min, in both the mutants and wt. However, the wt and f104 both displayed larger amplitudes of both de-epoxidation lifetimes than f2. The difference between the final de-epoxidation state (DES = [Z + A]/[V + A + Z]) in the light compared to the dark expressed as ΔDES for wt, f104, and f2 was 0.630, 0.623, and 0.420, respectively. The slow lifetime component and overall larger ΔDES in the wt and f104 correlated with more photoprotection, as indicated by relatively higher Fv/Fm and ΦPS2, compared to the f2. Hence the photoprotection against photoinhibition has no relationship with the absolute DES value, but there is a strong relationship with de-epoxidation rate and relative extent or ΔDES. and Chang-Lian Peng ... [et al.].

Language:

Multiple languages

Rights:

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

Coverage:

503-508

Source:

Photosynthetica | 2002 Volume:40 | Number:4

Harvested from:

CDK

Metadata only:

false