PHOTOSYNTHETICA

Photosynthetica 2002, 40(3):349-354 | DOI: 10.1023/A:1022614722629

High Contents of Anthocyanins in Young Leaves are Correlated with Low Pools of Xanthophyll Cycle Components and Low Risk of Photoinhibition

Y. Manetas¹, A. Drinia¹, Y. Petropoulou¹

¹ Laboratory of Plant Physiology, Department of Biology, University of Patras, Patras, Greece

We checked the hypothesis that the transient presence of anthocyanins in young leaves serves a photoprotective function. For this purpose, Rosa sp. and Ricinus communis L., whose young leaves are red to become green upon maturation, were used. Thus, young leaves with high and mature leaves with low anthocyanin contents were analysed concerning their carotenoid (Car) composition and susceptibility to photoinhibition. Cars, including the components of the xanthophyll cycle, had similar contents in young and mature leaves, when expressed on a chlorophyll basis. Yet, when expressed on a leaf area basis or on the assumed photon absorptive capacity of leaves, Cars contents were considerably lower in anthocyanic young leaves. Although this may indicate a low photodissipative potential, red young leaves were considerably less susceptible to photoinhibitory damage. The results are compatible with a photoprotective function of anthocyanins, indicating also that their presence may compensate for a low capacity in the xanthophyll cycle-dependent harmless dissipation of excess excitation energy.

Additional key words: carotenoids; chlorophylls; fluorescence kinetics; leaf age; photosystem 2; Ricinus communis; Rosa sp.

Published: September 1, 2002  Show citation