The impact of precipitation and temperature on seed ripening and germination dynamics of some meadow species of Western and Central Europe

Weather fluctuations can influence germination dynamics and pose a threat to the conservation of perennial lowland hay meadow species (Natura 2000 habitat code 6510). This study aims to assess the effects of temperature and precipitation changes on the germination performance of 23 plant species, divided into two harvest periods (July and late September/early October) of a two-year collection (2022–2023). The study classifies these species based on shared germination characteristics and identifies key parameters influencing germination performance. Germination tests were conducted in Petri dishes at 20 °C for 16 hours (dark) and 30 °C for 8 hours (light), with a light intensity of 1000 lux. Quantitative (GC - germination capacity, FUS - fresh ungerminated seeds, and DS - dead seeds) and qualitative ( t ₅₀ – the half of germination time, T. Index - Timson index) aspects were analysed using a two-way ANOVA test. Results revealed significant interactions between species and weather conditions across both collection periods. Wetter conditions increased GC and shortened t ₅₀ associated with rising germination velocity in most species, while warmer and drier conditions prolonged t ₅₀ and increased DS share. Heatmap clustering revealed that several species, including Tragopogon pratensis , Dianthus deltoides , and Centaurea jacea , demonstrated stable germination performance, making these species promising candidates for restoration. The decision tree identified Timson index as the most influential parameter explaining GC. These findings demonstrate that understanding germination dynamics caused by climate change may aid conservation-oriented restoration efforts for native species, enabling the implementation of seed mixtures of introduced species and informed decisions on the optimal time for seed recruitment.