Cryopreservation and post-thaw genetic integrity of Viola stagnina Kit., an endangered species of wet habitats – A useful tool in ex situ conservation

•Micropropagation combined with cryopreservation delivers an efficent ex situ conservation toolbox for V. stagnina.•Cryoprotection does not affect genome size, it generates low genetic diversity of post-thaw recovered plants.•The studies may be helpful in conservation of the other rare and threatened plant species as well.