Multidisciplinary approaches for species delimitation in Sisyrinchium (Iridaceae).
Multidisciplinary approaches for species delimitation in Sisyrinchium (Iridaceae).
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DOI：
10.1111/1442-1984.12181
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发表时间：
2018
影响因子：
1.4
通讯作者：
J. Fachinetto;E. Kaltchuk‐Santos;C. D. Inácio;L. Eggers;T. Souza-Chies
中科院分区：
文献类型：
--
作者：
J. Fachinetto;E. Kaltchuk‐Santos;C. D. Inácio;L. Eggers;T. Souza-Chies
不同种群的水仙草自然居群形态上的相似性显著。(蝴蝶科)使一些种的分类变得困难。本文研究了两种形态特征不同的卷叶链霉菌(MC-I和MC-II)。进行了形态、细胞遗传学、生殖生物学和遗传学研究，旨在阐明和更好地描述这种变异。该物种的基本染色体数目为x=9，MC-I有二倍体和四倍体群体，而MC-II只有二倍体群体。不同形态类型的花粉形态不同。授粉试验表明，MC-I为异交，MC-II为自交。种群分化程度较高(Fst=0.46，θB=0.62)。在MC-I中，观察到的变异在种群内(69%)大于种群间(31%)，而在MC-II中，61%的变异发生在种群之间，39%的变异发生在种群内。这一研究证明，这两个形态类型对应于不同的和繁殖隔离的物种，花部性状反映了它们的繁殖系统，MC-I的异花授粉植株和MC-II的自交植株。此外，MC-II在巴西被发现为被忽视的Sisyrinchium的一个分类单元--S.Platycaule。这项研究中应用的工具基本上能够检查这两个形态类别作为两个不同物种的身份，并展示在分类群中遇到的变异。
A remarkable morphological similarity in natural populations of different groups of Sisyrinchium spp. (Iridaceae) makes classification of some species difficult. The present paper focused on two morphological categories of S. sellowianum (MC-I and MC-II) with distinct morphological traits. Morphological, cytogenetic, reproductive biology and genetic studies were performed, aiming to elucidate and better characterize such variation. The basic chromosome number established for the species was x = 9 and diploid and tetraploid populations were observed for MC-I, whereas MC-II showed only diploid populations. Different pollen morphologies were recognized in each morphological category. Based on pollination experiments, MC-I is out-crossing, whereas MC-II is selfing. The populations were highly differentiated (FST = 0.46, θB = 0.62). In MC-I, observed variation was greater within populations (69%) than among populations (31%), whereas in MC-II, 61% of the variation was among populations and 39% within populations. This study evidenced that the two morphological categories correspond to distinct and reproductively isolated species and that floral traits reflect their breeding system, with allogamous plants in MC-I and autogamous in MC-II. Furthermore, MC-II is unveiled as S. platycaule, a neglected taxon of Sisyrinchium in Brazil. The tools applied in this study were substantially able to check the identity of the two morphological categories as two different species and present the variation encountered in the taxa.