A Successful in vitro Propagation Technique for Resurrection Plants of the Selaginellaceae

Resurrection plants of the Selaginellaceae are renowned for their ability to tolerate desiccation as well as the small size of their nuclear genomes. These traits position Selaginella as a promising model system to understand many aspects of plant evolution. However, there is not an established method for the laboratory cultivation of resurrection species of Selaginella. We explored methods of in vitro propagation for resurrection species of Selaginella and identified a set of successful techniques. Our in vitro propagation system included two main steps: surface-sterilized megaspores were cultured alone on C-Fern agar medium for three weeks, followed by the addition of surface-sterilized microspores to the germinated megaspore cultures for co-culture. Sporelings of Selaginella eremophila and S. rupincola were observed after 2-5 weeks of co-culture, and all sporelings survived. Our methods aim to further the interest and use of resurrection species of Selaginella for manipulative studies to better understand the biology of desiccation tolerance and their unique genome architecture.