Format: ORAL

Veronica Malavasi1,2, Nria Beltran-Sanz1, Sofia Stocco1, Fernando T. Maestre3, Francesco Dal Grande1

1 University Centre Botanical Garden, University of Padua, Italy 2 Department of Botany, Charles University, Prague, Czech Republic 3 Department of Ecology, University of Alicante, Spain

In dryland ecosystems, soil microbial communities are intricately linked to ecosystem functioning because they play an important role in carbon and nitrogen cycling, soil fertility and climate regulation. Unicellular green algae are crucial components of these communities with key roles in primary production, food webs, nutrient cycling, soil formation, and modulation of soil texture and structure. Despite its importance and interest in biotechnological exploitation, the phototrophic micro-algal flora represents a vastly understudied component of soil microbial communities. Limited knowledge of the diversity and the adaptive traits important for survival in extreme environments translates into a limited ability to monitor and eventually prevent biodiversity losses. This study aimed to create a genomic library of representative strains of green algae isolated from desert soils worldwide. A collection of 23 soil samples from 14 countries, collected within the framework of the BIODESERT project, was used for this purpose. The newly generated genomes and transcriptomes from several strains representing over 15 genera of the Chlorophyta and Charophyta divisions allow testing the hypothesis of genomic convergence in the adaptation to desert environments in green algae. Our newly genomic library constitutes a novel resource for metagenomics-based monitoring of functional biodiversity in desert soil microbial communities and a better-informed prediction of the ecological implications of climate change on soil biodiversity. Additionally, the results of this initial screening pave the way for the biotechnological exploitation of this vital yet understudied component of desert ecosystems.