Gender, mediterranean drought, and seasonality: photosystem II photochemistry in Pistacia lentiscus L

• Published in: Photosynthetica Vol. 51; no. 4; pp. 552 - 564
• Main Authors: Ait Said, S., Torre, F., Derridj, A., Gauquelin, T., Mevy, J. P.
• Format: Journal Article
• Language: English
• Published: Praha The Institute of Experimental Biology of the Czech Academy of Sciences 01-12-2013; Springer Verlag
• Subjects: Biodiversity and Ecology; Biomedical and Life Sciences; Environmental Sciences; Life Sciences; Original Papers; Plant Physiology; carotenoids; fluorescence; sex; chlorophyll; aridity; photoinhibition; L; seasonality
• ISSN: 0300-3604; 1573-9058
• DOI: 10.1007/s11099-013-0055-9

In this work, photosystem II (PSII) photochemistry, leaf water potential, and pigment contents of male and female
Pistacia lentiscus
L. were investigated during a seasonal cycle at three different, arid locations: superior semiarid, inferior semiarid, and arid. The results showed that the gender, season, and the site conditions interacted to influence the quantum yield and pigment contents in
P. lentiscus
. Predawn leaf water status was determined only by the site and season. The annual patterns of PSII maximum quantum efficiency (F
v
/F
m
) were characterized by a suboptimal activity during the winter, especially, populations with the more negative water potential exhibited a lower chlorophyll (Chl)
a
content and chronic photoinhibition irrespective of a gender. We also demonstrated that both photochemical or nonphotochemical mechanisms were involved to avoid the photoinhibition and both of them depended on the season. This plasticity of photosynthetic machinery was accompanied by changes in carotenoids and Chl balance. In the spring, the female F
v
/F
m
ratio was significantly higher than in male individuals, when the sexual dimorphism occurred during the fruiting stage, regardless of site conditions.
P. lentiscus
sex-ratio in Mediterranean areas, where precipitations exceeded 500 mm, was potentially female-biased. Among the fluorescence parameters investigated, nonphotochemical quenching coefficient appeared as the most useful one and a correlation was found between Chl
a
content and F
v
/F
m
. These results suggest that functional ecology studies would be possible on a large scale through light reflectance analysis.