| Summary: | Cryopreservation is one way to preserve rare, endangered species. However, during the cryopreservation process, plant cells undergo considerable stress, which may lead to cell death. In our work, orthodox <i>Stipa</i> seeds of six rare species were cryopreserved: <i>S. sareptana</i>, <i>S. ucrainica</i>, <i>S. tirsa</i>, <i>S. dasyphylla</i>, <i>S. adoxa</i>, and <i>S. pulcherríma</i>. Short-term cryopreservation (14 days) stimulated germination of all <i>Stipa</i> species studied. Prolonged cryopreservation (70 days and more) decreased the germination of all <i>Stipa</i> seeds except <i>S. sareptana</i>. The decrease in germination progressed over time as a result of the cumulative stress of cryopreservation rather than the initial stress. To stimulate germination, seeds were stratified and treated with GA<sub>3</sub>, KNO<sub>3</sub>, NaOH, and H<sub>2</sub>O<sub>2</sub>. After four years of seed cryopreservation, it was possible to obtain seedlings of all the <i>Stipa</i> species studied with 30 days of stratification and 180 days of germination. After five years of cryopreservation and seed treatment with 30% NaOH for one hour, the best germination was obtained in <i>S. adoxa</i> and <i>S. pulcherrima</i>. After treatment with 5% H<sub>2</sub>O<sub>2</sub> for 20 min, the best germination was obtained in <i>S. sareptana</i>, <i>S. ucrainica</i>, and <i>S. dasyphylla</i>. <i>S. sareptana</i> seeds germinated in all the aforementioned experiments. <i>S. sareptana</i> has a non-deep physiological dormancy and is the most widespread and drought-tolerant <i>Stipa</i> species studied. The best habitat adaptation and stress tolerance correlated with this species’cryotolerance. <i>S. sareptana</i> was recommended for further cryopreservation, while storage protocols for the other <i>Stipa</i> species studied need further improvements.
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