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In this work, using a PAM-fluorimetry technique, we have compared effects of plant adaptation to the light or dark conditions on the kinetics of chlorophyll a fluorescence yield in Tradecantia leaves of several species (Tradescantia albiflora, Tradescantia fluminensis, Tradescantia navicularis, and Tradescantia sillamontana), which represent plants of different ecotypes. Two fluorescence parameters were used to assess photosynthetic performance in vivo: non-photochemical quenching (NPQ) of chlorophyll fluorescence (qNpQ) determined by energy losses in the light-harvesting antenna of photosystem 2 (PS2), and PS2 operating efficiency (Phi(PSII)). Comparative study of light-induced changes in C/NpQ and Phi(PSII) has demonstrated that shade-tolerant Tradecantia species (T. albiflora Kunth, T. fluminensis Veil.) reveal higher capacities for NPQ and demonstrate slower transitions between the ’light-adapted’ and ’dark-adapted’ states than succulent species T. navicularis and T. sillamontana, which are typical habitats of semi-deserts. We analyze the photosynthetic performance of Tradescantia species in the context of their adaptabilities to variable environment conditions. The ability of shade-tolerant plants to retain a relatively long-term (similar to 40-60 min) ’memory’ for illumination history may be associated with the regulatory mechanisms that provide the flexibility of photosynthetic apparatus in response to fluctuations of light intensity. (C) 2011 Elsevier Ireland Ltd. All rights reserved.