PHOTOSYNTHETICA

Photosynthetica 2016, 54(1):143-147 | DOI: 10.1007/s11099-015-0161-y

Photosynthesis and photoprotection under drought in the annual desert plant Anastatica hierochuntica

A. Eppel^1,*, S. Rachmilevitch¹

¹ French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Negev, Israel

Anastatica hierochuntica is an annual desert plant, which was recently shown to have unusually low nonphotochemical quenching (NPQ) and a high PSII electron transport rate (ETR). In the current study, we examined how these unusual characteristics are related to a lack of CO₂ and inhibition of net photosynthetic rate (P _N). We compared the photosynthetic and photoprotective response of A. hierochuntica and sunflower (Helianthus annuus), under conditions of photosynthetic inhibition, with either low CO₂ or drought. We found that under nonsteady state conditions of low CO₂ availability, A. hierochuntica exhibited about half of the NPQ values and almost twice of the ETR values of H. annuus. However, the long-term inhibition of P _N under drought caused a similar increase in NPQ and a decrease in ETR in both A. hierochuntica and H. annuus. These results suggest that the unusually low NPQ and high ETR in A. hierochuntica are not directly related to a response to drought conditions.

Additional key words: abiotic stress; relative water content; stomatal conductance

Received: November 3, 2014; Accepted: June 22, 2015; Published: March 1, 2016  Show citation