Leaf and culm silicification of Pampas grass (Cortaderia selloana) developed on different soils from Pampean region, Argentina

FERNÁNDEZ HONAINE, MARIANA; BORRELLI, NATALIA; OSTERRIETH, MARGARITA; DEL RÍO, LUIS

AUSTRALIAN JOURNAL OF BOTANY

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2017 vol. 65 p. 1 - 10

0067-1924

Amorphous silica accumulation in grasses is widely described in numerous species; however, work done inrelation to the factors affecting this accumulation in the tissues and different type of cells, is still incipient. Here, we analysed aperennial tussock grass, Cortaderia selloana (Schult. & Schult.f.) Asch. & Graebn. (Pampas grass), a native and widelyspread species from South America, which is also considered an invasive plant in many regions of the world.Weanalysed therelation between silicification process, soil type and environment, and anatomical features. Silicophytolith content anddistribution in plants was analysed through calcination and staining techniques and SEM-EDAX analyses. Silicophytolithcontent was higher in leaves (2.48?5.54% DW) than in culms (0.29?0.43% DW) and values were similar to other tussockgrasses. A relationship between the habit of a grass species and the potential maximum content of amorphous silica issuggested. Plants grown in soils from modified environments with high silica content (Anthrosol and Tecnosol) produced ahigher content of amorphous silica. In leaves, the distribution of silicified cells was conditioned by leaf xeromorphic features.Soil Si content and environmental conditions (radiation, disturbance) are more relevant in silicification process thanphenological factors. Within leaves, the accumulation of amorphous silica is conditioned by anatomy and transpiration.