Cardamine bulbifera (Coralroot Bittercress) is one of the Central European enigmatic plant species. Although the species is wide-spread all over Europe, no reproduction via seeds has ever been observed. Instead dispersal of vegetative leaf-axillary bulbs assures effective propagation. In our study we analyzed different life stages and factors affecting sexual reproduction and seek for unravelling the evolutionary origin of this polyploid species. We combined studies on pollen quality and fertility, pollen-stigma interactions, growth performance, and reproductive success with common garden experiments, controlled pollination and genotyping analysis (AFLPs). We also tested the interplay of resource allocation either into developing fruits and seeds or into reproductive organs generated by vegetative means. Cytogenetic analyses were conducted addressing variation in chromosome numbers and ploidy level. Phylogenetic relationships among possible parental lineages of Eurasian Cardamine species were reconstructed based on whole plastome sequences and the entire nuclear encoded rDNA cistron. We have shown herein that sexual reproduction of Cardamine bulbifera is hindered at various stages of reproductive development. We did not find any complete interruption of reproductive development except final embryo arrest. We detected low pollen germination rates and slow pollen tube growth. Less than 25 % of flowers matured into siliques with most often low-quality seeds; only 2% of those seeds developed towards early stages of germination but arrested before primary root formation. Results are independent from genotypes or vegetative propagation. Phylogenetic data demonstrate close relationships to C. quinquefolia and C. abchasica, but don’t indicate a hybrid origin involving distant species from other lineages. Cardamine bulbifera is a fully functional sexual plant with attractive flowers, nectar production, viable pollen, functional ovules and no signatures of a sporophytic incompatibility system. Highly reduced seed set and failure in seedling formation may be causally linked to a polyploid origin in the Caucasus region. Long-term survival has been achieved by rapid transition towards vegetative propagation and subsequent range expansion.

碎米花（Coralroot Bittercress）是中欧神秘植物之一。尽管该物种在欧洲广泛分布，但从未观察到通过种子繁殖。相反，植物叶腋鳞茎的散布可确保有效繁殖。在我们的研究中，我们分析了不同的生活阶段和影响有性生殖的因素，并试图阐明该多倍体物种的进化起源。我们将有关花粉质量和繁殖力，花粉-柱头相互作用，生长表现和生殖成功的研究与普通的花园试验，可控的授粉和基因分型分析（AFLP）相结合。我们还测试了资源分配在发育中的果实和种子中或在通过营养手段产生的生殖器官中的相互作用。进行了细胞遗传学分析，以解决染色体数目和倍性水平的变化。欧亚可能亲代谱系之间的亲缘关系根据完整的质体序列和完整的核编码的rDNA顺反子，重建了豆蔻胺物种。我们已经在本文中证明了在干燥发育的各个阶段都阻碍了豆蔻胺的有性繁殖。除了最终的胚胎停滞，我们没有发现生殖发育完全中断。我们检测到低的花粉发芽率和缓慢的花粉管生长。不到25％的花朵以低劣的种子成熟为长角果；这些种子中只有2％的种子在发芽的早期阶段发育，但是在初生根形成之前就被捕了。结果与基因型或营养繁殖无关。系统发育数据表明，其与西洋参和阿德茶具有密切的关系。，但不要指出杂种起源涉及其他世系的远缘物种。豆蔻是一种功能齐全的有性植物，具有迷人的花朵，花蜜产生，可行的花粉，功能性胚珠，并且没有孢子体不相容系统的特征。高度减少的结实和幼苗形成的失败可能与高加索地区的多倍体起源有因果关系。通过向营养繁殖和随后范围扩大的快速过渡，可以实现长期生存。