Effect of different conditions of storage on seed viability and seedling growth of six European wild fruit woody plants

Key message Malus sylvestris (L.) Mill., Pyrus communis (L.), Sorbus aucuparia (L.), Prunus avium (L.), Prunus padus (L.), and Cornus sanguinea (L.) are related, co-occurring species producing orthodox seeds. However, we observed differences in their response to storage conditions, such as storage at different seed moisture contents (5%, 8%, and 11%) and/or temperatures (− 3 °C, − 18 °C, and − 196 °C). Severe desiccation to ca. 5% of MC negatively affected seeds of M. sylvestris . Seeds of P. avium were sensitive to storage in LN or at − 18 °C. S. aucuparia seeds are best stored at − 3 °C, whereas C. sanguinea seeds tolerate desiccation and storage in LN. In general, species with deeper physiological dormancy ( S. aucuparia , P. padus , and C. sanguinea ) tended to be more tolerant to desiccation and low temperatures. For all species, storage conditions did not affect seedling growth. Context Wild fruit woody species face many threats such as genetic loss, population fragmentation, and alien species; thus, their genetic variability should be preserved. Aims To examine the effect of storage conditions on seed viability and the initial growth of seedlings of six European wild fruit species: Malus sylvestris (L.) Mill., Pyrus communis (L.), Sorbus aucuparia (L.), Prunus avium (L.), Prunus padus (L.), and Cornus sanguinea (L.). Methods Seeds were desiccated to three different levels of moisture content (ca. 5, 8, or 11%) and stored at three different temperatures (− 3°, − 18°, or − 196 °C; liquid nitrogen, LN) for up to 3 years. Germination and seedling emergence tests were performed as well as measurement of seedling growth. Results Desiccation of M. sylvestris seeds from 10.7 to 4.9% significantly lowered germination from 91 to 77% and seedling emergence from 88 to 74%. In P. avium , LN storage significantly inhibited seedling emergence, both in the laboratory and the greenhouse, but did not affect total seed germination. In P. communis , P. padus , and C. sanguinea , neither germination nor seedling emergence was affected by seed storage conditions. There were small or no differences in stem height and root collar diameter in the first year of seedling growth of stored seeds. Conclusion Species with deeper physiological dormancy ( S. aucuparia , P. padus , C. sanguinea ) tended to be more tolerant of various storage conditions. Seeds of P. padus and C. sanguinea can be stored long term at − 18 °C or in LN at 5–8% MC without losing viability. M. sylvestris a