Seed germination ecology in Trapa natans L., a widely distributed freshwater macrophyte

摘要: Abstract Trapa natans is an aquatic annual plant that grows in stagnant water and occupies extremely wide, yet discontinuous native range across temperate Europe, Asia, Africa, naturalized North America Australia. Despite its wide distribution invasion success, seed germination ecology poorly known. We hypothesized that, due to range, T. seeds should germinate under a broad spectrum of environmental conditions. In the present study, freshly matured were cold stratified tested for over temperatures light/dark, dark aerobic hypoxia Seed seedling tolerance freezing desiccation also determined. Freshly physiologically dormant, requiring 9 weeks stratification overcome dormancy. Seeds tolerated down −14 °C, whereas those with emerged hypocotyl exhibited high sensitivity −4 °C. The non-dormant germinated (75–100%) almost all conditions, i.e. constant 22 °C alternating temperature 14/6 °C 30/22 °C 30/10 °C, light darkness, oxic hypoxia, thus supporting our proposed hypothesis. Finally, found be highly desiccation-sensitive, even at relative humidity. Our findings suggest niche could help explain success local global scales.