Role of xanthophyll cycle-mediated photoprotection in Arbutus unedo plants exposed to water stress during the Mediterranean summer

Title:

Role of xanthophyll cycle-mediated photoprotection in Arbutus unedo plants exposed to water stress during the Mediterranean summer

Creator:

Baraldi, R., Canaccini, F., Cortes, S., Magnani, F., Rapparini, F., Zamboni, A., and Raddi, S.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:6c52d66e-4973-466b-ae5d-1bf9bef71522
uuid:6c52d66e-4973-466b-ae5d-1bf9bef71522
issn:0300-3604
doi:10.1007/s11099-008-0069-x

Subject:

chlorophyll, fluorescence induction, net photosynthetic rate, photochemical efficiency, photoprotection, photosystem 2, stomatal conductance, strawberry tree, violaxanthin, water potentia, and zeaxanthin

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

We analyzed the response of potted strawberry tree (Arbutus unedo L.) seedlings exposed to water stress by withholding water for 10 d (WS). Leaf water potential, net CO2 assimilation, and stomatal conductance decreased with increasing water deficit. A 30 % reduction of chlorophyll (Chl) content in the antenna complexes was observed in WS-plants. Simultaneously, a decline of photochemical efficiency (Fv/Fm) occurred as a result of an excess of solar radiation energy when carbon assimilation was limited by stomata closure due to soil water deficit. The non-photochemical quenching of Chl fluorescence (ΦNPQ) significantly increased, as well as the leaf contents of zeaxanthin (Z) and antheraxanthin (A) at the expense of violaxanthin during the WS-period. Elevated predawn contents of de-epoxidized xanthophyll cycle components were associated with a sustained lowering of predawn photosystem 2 efficiency; this suggested an engagement of Z+A in a state primed for energy dissipation. Thus, the ability of strawberry trees to maintain the functionality of the xanthophyll cycle during the Mediterranean summer is an efficient mechanism to prevent irreversible damages to the photosynthetic machinery through thermal energy dissipation in the antenna and the reduction in photochemical efficiency. and R. Baraldi ... [et al.].

Language:

Multiple languages

Rights:

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

Coverage:

378-386

Source:

Photosynthetica | 2008 Volume:46 | Number:3

Harvested from:

CDK

Metadata only:

false