How do vascular plants perform photosynthesis in extreme environments? An integrative ecophysiological and biochemical story.

Fernández Marín, B., Gulías, J., Figueroa, C. M., Iñiguez, C., Clemente Moreno, M. J., Nunes Nesi, A.,; Fernie Alisdair R.; Cavieres, Lohengrin A; Bravo, León A.; García?Plazaola, José I.; Gago, Jorge


In this work, we review the physiological and molecular mechanisms that allow vascular plants to perform photosynthesis in extreme environments, such as deserts, polar and alpine ecosystems. Specifically, we discuss the morpho/anatomical, photochemical and metabolic adaptive processes that enable a positive carbon balance in photosynthetic tissues under extreme temperatures and/or severe water‐limiting conditions in C3 species. Nevertheless, only a few studies have described the in situ functioning of photoprotection in plants from extreme environments, given the intrinsic difficulties of fieldwork in remote places. However, they cover a substantial geographical and functional range, which allowed us to describe some general trends. In general, photoprotection relies on the same mechanisms as those operating in the remaining plant species, ranging from enhanced morphological photoprotection to increased scavenging of oxidative products such as reactive oxygen species. Much less information is available about the main physiological and biochemical drivers of photosynthesis: stomatal conductance (g s), mesophyll conductance (g m) and carbon fixation, mostly driven by RuBisCO carboxylation. Extreme environments shape adaptations in structures, such as cell wall and membrane composition, the concentration and activation state of Calvin–Benson cycle enzymes, and RuBisCO evolution, optimizing kinetic traits to ensure functionality. Altogether, these species display a combination of rearrangements, from the whole‐plant level to the molecular scale, to sustain a positive carbon balance in some of the most hostile environments on Earth.

Más información

Título de la Revista: The Plant Journal
Volumen: 101
Número: 4
Fecha de publicación: 2020
Página de inicio: 979
Página final: 1000
Idioma: ingles