Exploring the Uniqueness of Photosynthetic and Hydraulic Traits of Antarctic Vascular Plants: A Comparative Study with Related Species.

Deschampsia antarctica and Colobanthus quitensis are extremophile species thriving from the Andes to the Subantarctic regions. Although they share this gradient with other species, notably, they are the only flowering plants growing naturally in Antarctica. These species exhibit traits typical of xeromorphy, such as high leaf mass area (LMA) and leaf density (LD), which influence mesophyll conductance and photosynthesis.

Hydraulic and Photosynthetic Performance of Antarctic Plants Under Successive Freeze-Thaw Cycles.

Climate change projections predict warming and increased weather variability, mainly in polar regions, altering freeze-thaw patterns. However, the effects of rising temperatures and more frequent freeze-thaw events on the water and CO management of Antarctic plants remain unclear. To address this, we conducted a laboratory experiment to investigate how growth temperature (5°C and 15°C) and successive freeze-thaw cycles influence the hydraulic and photosynthetic performance of Deschampsia antarctica (D.

In Situ Accumulation of CaOx Crystals in Leaves and Its Relationship with Anatomy and Gas Exchange.

The accumulation of crystal calcium oxalate (CaOx) in plants is linked to a type of stress-induced photosynthesis termed 'alarm photosynthesis', serving as a carbon reservoir when carbon dioxide (CO) exchange is constrained. is an extremophyte found from southern Mexico to Antarctica, which thrives in high-altitude Andean regions. Growing under common garden conditions, from different latitudinal provenances display significant variations in CaOx crystal accumulation.

Ecophysiology of Antarctic Vascular Plants: An Update on the Extreme Environment Resistance Mechanisms and Their Importance in Facing Climate Change.

Antarctic flowering plants have become enigmatic because of their unique capability to colonize Antarctica. It has been shown that there is not a single trait that makes and so special, but rather a set of morphophysiological traits that coordinately confer resistance to one of the harshest environments on the Earth. However, both their capacity to inhabit Antarctica and their uniqueness remain not fully explained from a biological point of view.

Anatomical and biochemical evolutionary ancient traits of Araucaria araucana (Molina) K. Koch and their effects on carbon assimilation.

The study of ancient species provides valuable information concerning the evolution of specific adaptations to past and current environmental conditions. Araucaria araucana (Molina) K. Koch belongs to one of the oldest families of conifers in the world, but despite this, there are few studies focused on its physiology and responses to changes in environmental conditions.

In situ warming in the Antarctic: effects on growth and photosynthesis in Antarctic vascular plants.

The Antarctic Peninsula has experienced a rapid warming in the last decades. Although recent climatic evidence supports a new tendency towards stabilization of temperatures, the impacts on the biosphere, and specifically on Antarctic plant species, remain unclear. We evaluated the in situ warming effects on photosynthesis, including the underlying diffusive, biochemical and anatomical determinants, and the relative growth of two Antarctic vascular species, Colobanthus quitensis and Deschampsia antarctica, using open top chambers (OTCs) and gas exchange measurements in the field.

Effects of temperature and water availability on light energy utilization in photosynthetic processes of Deschampsia antarctica.

Regional climate change in Antarctica would favor the carbon assimilation of Antarctic vascular plants, since rising temperatures are approaching their photosynthetic optimum (10-19°C). This could be detrimental for photoprotection mechanisms, mainly those associated with thermal dissipation, making plants more susceptible to eventual drought predicted by climate change models. With the purpose to study the effect of temperature and water availability on light energy utilization and putative adjustments in photoprotective mechanisms of Deschampsia antarctica Desv.