Phytolith extraction and counting procedure for modern plant material rich in silica skeletons v1
Authors: D’Agostini Francesca , Ruiz-Pérez Javier , Madella Marco , Vadez Vincent , Lancelotti Carla 
Published: May 2022

Modern plant tissues are often processed for phytolith analysis. They represent a fundamental source of comparison for archeological and palaeoenvironmental phytolith assemblages; they efficiently serve for morphological studies of phytolith shapes and dimensions and, in the last two decades, they have been increasingly involved in physiological studies, which aim to understand the functioning of Si absorption in plants. Here we present a relatively fast, safe, and inexpensive phytolith extraction, combining a dry ashing technique followed by wet oxidation, and a counting methodology. This protocol offers an optimized strategy that achieves very pure samples, preservation of a high number of silica skeletons (phytoliths in anatomical connection), and a counting method which assures the richness and the evenness of the phytolith assemblage distribution. 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