Specific ultrastructure of the leaf mesophyll cells of Deschampsia antarctica Desv. (Poaceae) / Ultrastruktura komórek mezofilu liści Deschampsia antarctica Desv. (Poaceae)

Hierachical epicuticular wax coverage on leaves of Deschampsia antarctica as a possible adaptation to severe environmental conditions

“…The presence of a thick wax coverage has been considered as one of typical xeromorphic features (i.e., structural characteristics that leaves of plants growing under arid conditions have in common in order to drastically lessen the water loss from leaves and are, therefore, classed as adaptational mechanisms to withstand drought [42]). Such leaf characteristics as small epidermal cells, high cell density per area, considerable leaf thickness, thickwalled tissues, thick cuticles, and some other structural features typical of xerophytes were repeatedly revealed in D. antarctica by different authors [4,[8][9][10][11][12]. As for the epicuticular wax in this plant species, it has been previously reported that the wax on both epidermis and stomata contributes to the resistance of water vapor diffusion from the mesophyll to the outside and to the control of cuticle transpiration, reducing in this way the water loss by the leaf blade [9].…”

“…As for the epicuticular wax in this plant species, it has been previously reported that the wax on both epidermis and stomata contributes to the resistance of water vapor diffusion from the mesophyll to the outside and to the control of cuticle transpiration, reducing in this way the water loss by the leaf blade [9]. Also, authors associated the epicuticular wax on leaves along with certain anatomical features of the leaf mesophyll cells [4,8] to the protection of D. antarctica against dehydration. Based on our cryo-SEM results, we assume that, in this plant species, particularly the compact lower wax layer, which resembles the wax crusts characteristic for many succulents (e.g., Asclepiadaceae and Cactaceae) [15], plays a crucial role in the protection from water loss.…”

“…(Caryophyllaceae), which is rather rare and mainly relays on an avoidance strategy (i.e., it grows near higher clumps of D. antarctica or in hollows between stones avoiding direct influence of unfavorable abiotic factors), the Antarctic hair grass not only uses the avoidance strategy, but also grows in separate agglomerations or forms thick covers on the unprotected ground surface [3]. Especially in the latter case, D. antarctica plants are fully exposed to the cold desert climate of Antarctica, including low temperatures, moisture deficit, and strong ultraviolet radiation [2,4].…”

“…In view of the remarkable success of this plant species in the colonization of the Maritime Antarctica (i.e., ice-and snow-free lands along the Antarctic Peninsula, its associated islands, and coastal regions around the rest of the Antarctic continent accounting for less than 1% of the Antarctica territory [5]), intensive experimental investigations were recently performed on structural, physiological, genetical, and molecular biological characteristics of D. antarctica, in order to find specialized adaptations to severe environmental conditions that ensure this evolutionary success [2][3][4]6]. Structural studies that have been focused mainly on anatomical and ultrastructural characterization of leaves [4,[7][8][9][10][11][12] did not reveal any qualitative traits allowing for a distinction of this plant from other polar species and explaining its better survival in the Antarctica region. The leaves exhibit xerophytic (i.e., typical for plants growing in arid places) morphological and anatomical attributes, and the general anatomical features of mesophyll cells are similar to those of other plant species growing in cold regions [13] and to those in other grass leaves.…”

Influence of environmental change on monolignols and the micromorphology of leaf epidermis in hydrophytes and terrestrial plants

“…A study of the epidermis ultrastructure in the leaves of Deschampsia antarctica collected during the 20th Ukrainian Antarctic Expedition showed that the morphoanatomical traits of the leaves collected on the islands Scua and Galindez are similar to those of the species from other regions of the Maritime Antarctic [109][110][111][112]. It was found that all the leaves of the studied species twisted in a tube-shaped curl.…”