Carotenoid composition and photochemical activity of four sandy grassland species

Title:

Carotenoid composition and photochemical activity of four sandy grassland species

Creator:

Veres, S., Tóth, V. R., Láposi, R., Oláh, V., Lakatos, G., and Mészáros, I.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:8f21ff37-b011-4257-9f04-e122cb1fdd1f
uuid:8f21ff37-b011-4257-9f04-e122cb1fdd1f
issn:0300-3604
doi:10.1007/s11099-006-0016-7

Subject:

dry mass, photochemical efficiency, photosystem 2, seasonal changes, and xanthophyll cycle

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The photosynthetic pigments and photochemical efficiency of photosystem 2 (PS2) were studied in four constitutive species (Achillea millefolium L., Festuca pseudovina Hack. ex Wiesb., Potentilla arenaria Borkh., and Thymus degenianus Lyka) of a semiarid grassland in South-eastern Hungary. Every species displayed typical sun-adapted traits and substantial plasticity in the composition and functioning of the photosynthetic apparatus. The contents of chlorophylls (Chls) and carotenoids (Cars) on a dry matter basis declined from May to July, however, the amount of total Cars on a Chl basis increased. This increase was the largest in Potentilla (48 %) and the smallest in Achillea (14 %). The pool of xanthophylls (VAZ) was between 25 % and 45 % of the total Car content and was larger in July than in May. The content of β-carotene increased by July, but lutein content did not change significantly. The Chl fluorescence ratio Fv/Fm was reduced by 3-10 % at noon, reflecting the down-regulation of PS2 in the period of high irradiance and high temperature. The occurrence of minimal values of ΔF/Fm' showed close correlation to the de-epoxidation rate of violaxanthin. Hence in natural habitats these species developed a considerable capacity to dissipate excess excitation energy in the summer period in their photosynthetic apparatus through the xanthophyll cycle pool and a related photoprotective mechanism, when the photochemical utilization of photon energy was down-regulated. and S. Veres ... [et al.]

Language:

Multiple languages

Rights:

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

Coverage:

255-261

Source:

Photosynthetica | 2006 Volume:44 | Number:2

Harvested from:

CDK

Metadata only:

false