Seed viability assessment in the genus Sideritis after ten years of germplasm bank conservation

Abstract

The present study assesses the viability of ten species of the genus Sideritis after ten years of ex situ conservation at the Germplasm Bank of the Botanic Garden of Castilla-La Mancha (GB-JBCLM). Two methods were employed to determine seed viability: the excised seed test and the germination method (under controlled conditions of 20/7°C and 12 hours light/12 hours dark). The results show that five of the ten species (S. lacaitae, S. lasiantha, S. fruticulosa, S. stachydioides and S. glacialis) exhibited viability values between 5% to 60% lower than those observed in previous studies with freshly collected seeds. This may be attributed to environmental factors or differences in tolerance to the conservation process. Furthermore, the germination method was found to be insufficient in this context, as it overlooks the dormant viable seeds present in some species, highlighting the need to complement it with the turgidity test to obtain a more accurate assessment. Consequently, the findings of this study, alongside further research on the effects of in situ environmental factors and the conservation process itself, is essential for optimal management of Sideritis species in germplasm banks.