Nirmala Jeyarani J, Yohannan Regy, Vijayavalli Devipriya, Dwivedi Mayank D, Pandey Arun K
Department of Botany, Fatima Mata National College (Autonomous), Kollam 691 001, India.
J Genet. 2018 Dec;97(5):1225-1239.
L. (Oleaceae) consists of ∼200 species that are distributed in tropical, subtropical and temperate regions of the world. In India, this genus is represented by ca 47 species of which 16 are endemic. Based on the nuclear (internal-transcribed spacer (ITS) region of nrDNA and chloroplast markers (K, L-F and H-A), phylogenetic relationships in 22 species including one variety of in India have been assessed. Maximum likelihood and Bayesian analyses from individual markers, as well as from combined dataset, reveal that the group is monophyletic if spp. are excluded from the analyses. Our analyses recovered three strongly supported clades. Ancestral character state reconstruction of taxonomically useful characters (leaf forms, leaf arrangement and flower colour) which were used to demarcate sections within the genus reveals homoplasy. Our study suggests that after split from the last common ancestor, there have been at least four reversals to unifoliolate condition. Pinnately compound leaf form evolved at least twice and trifoliolate condition evolved one time only. Alternate leaf form evolved at least twice, once inclade 1 and once in clade 3 and all the time from ancestors having opposite leaf forms. Flower colour evolution clearly depicts that clade 1 is yellow-flowered and clades 2 and 3 have admixture of white and yellow-flowered species. Our study suggests that yellow-flowered condition evolved from the white-flowered ancestor. The present study is first to estimate the evolutionary history of Indian Jasmines.
素馨属（木犀科）约有200个物种，分布于世界热带、亚热带和温带地区。在印度，该属约有47个物种，其中16个为特有种。基于nrDNA的核内转录间隔区（ITS）区域和叶绿体标记（K、L-F和H-A），对印度22个物种（包括一个变种）的系统发育关系进行了评估。对单个标记以及合并数据集进行的最大似然分析和贝叶斯分析表明，如果在分析中排除素馨属某些物种，该类群是单系的。我们的分析得到了三个得到有力支持的分支。对用于划分该属内各节的分类学有用特征（叶形、叶序和花色）进行祖先特征状态重建，结果显示存在同塑性。我们的研究表明，自最后一个共同祖先分化后至少有四次向单叶状态的逆转。羽状复叶形态至少进化了两次，三叶形态仅进化了一次。互生叶形态至少进化了两次，一次在分支1中，一次在分支3中，并且一直是从具有对生叶形态的祖先进化而来。花色进化清楚地表明，分支1是黄色花，分支2和3有白色花和黄色花物种的混合。我们的研究表明，黄色花状态是从白色花祖先进化而来的。本研究首次估计了印度茉莉的进化历史。
