College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, PR. China.
PLoS One. 2020 Oct 15;15(10):e0240432. doi: 10.1371/journal.pone.0240432. eCollection 2020.
Morphological indices of vegetative organs or reproductive organs, which are often used to analyze the evolution and classify Clematis, indicate that Clematis serratifolia and C. glauca could be related members at similar evolutionary levels. However, this assumption differs with phylogenetic studies based on genetics. Embryonic characteristics, which are more stable, are commonly used to estimate the phylogeny and evolution of angiosperms. We studied the microsporogenesis, microgametogenesis, megasporogenesis and macrogametogenesis development of C. serratifolia, and compared the early embryological characteristics among C. serratifolia, C. serratifolia and other Clematis species reported to provide a reference for the taxonomy of the genus Clematis. Our results showed that C. serratifolia and C. glauca differ in megaspore formation and nucellus types suggesting that they have originated from different ancestors. The differences among Clematis were mainly found in the type of the anther wall development, tapetum, pollen grains, megaspore formation and nucellus types.
营养器官和生殖器官的形态指标，常被用于分析铁线莲属植物的进化和分类，表明展毛铁线莲和甘青铁线莲可能是在相似进化水平上的相关成员。然而，这种假设与基于遗传学的系统发育研究不同。胚胎特征更稳定，通常用于估计被子植物的系统发育和进化。我们研究了展毛铁线莲的小孢子发生、小配子发生、大孢子发生和大配子发生发育，并比较了展毛铁线莲、展毛铁线莲和其他已报道的铁线莲属植物的早期胚胎特征，为铁线莲属的分类学提供了参考。我们的结果表明，展毛铁线莲和甘青铁线莲在大孢子形成和珠心类型上存在差异，表明它们起源于不同的祖先。铁线莲属植物的差异主要表现在花药壁发育类型、绒毡层、花粉粒、大孢子形成和珠心类型上。
