
TY  - JOUR
A1  - Manetas, Yiannis 
A1  - Petropoulou, Yiola 
A1  - Psaras, George K. 
A1  - Drinia, Antonia 
T1  - Exposed red (anthocyanic) leaves of <emph type="2">Quercus</emph> <emph type="2">coccifera</emph>  display shade characteristics
JF  - Functional Plant Biology
JO  - Functional Plant Biol.
Y1  - 2003
VL  - 30
IS  - 3
SP  - 265
EP  - 270
KW  - Chlorophyll fluorescence, photoinhibition, Quercus coccifera, shade character, xanthophylls.
UR  - https://doi.org/10.1071/FP02226 
N2  - Young leaves in some plants are transiently red due to the presence of anthocyanins, which disappear upon maturation. We investigated the hypothesis that light attenuation by anthocyanins may lead to a shade acclimation of the photosynthetic machinery in red leaves. We took advantage of the intra-species variation in anthocyanin levels of young, exposed leaves of Quercus coccifera. Thus, photosynthetic and photoprotective characteristics were compared in young green and red leaves of the same age, sampled from the corresponding phenotypes occupying the same habitat. Red leaves displayed several shade attributes like thinner laminae, lower Chl a/b ratios and lower levels of the xanthophyll cycle components and &#946;-carotene. In addition, although both leaf kinds had the same area based levels of chlorophylls, these pigments were excluded from the sub-epidermic anthocyanic cell layers, leading to a further reduction of effective mesophyll thickness and an increase in chlorophyll density. Accordingly, red leaves had higher absolute chlorophyll fluorescence signals. In spite of these apparent shade characters, red leaves were less prone to photoinhibition under mild laboratory conditions and displayed slightly but significantly higher PS II photochemical efficiencies at pre-dawn in the field. No differences in all the above measured parameters were found in mature green leaves of the two phenotypes. The results confirm the light acclimation hypothesis and are also compatible with a photoprotective function of anthocyanins. 
ER  -

