Li Xi, Jang Tae-Soo, Temsch Eva M, Kato Hidetoshi, Takayama Koji, Schneeweiss Gerald M
Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030, Vienna, Austria.
Makino Herbarium, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji-shi, Tokyo, 192-0397, Japan.
J Plant Res. 2017 Mar;130(2):273-280. doi: 10.1007/s10265-016-0888-y. Epub 2016 Dec 21.
Molecular phylogenetic studies have greatly improved our understanding of phylogenetic relationships of non-photosynthetic parasitic broomrapes (Orobanche and related genera, Orobanchaceae), but a few genera have remained unstudied. One of those is Platypholis, whose sole species, Platypholis boninsimae, is restricted to the Bonin-Islands (Ogasawara Islands) about 1000 km southeast of Japan. Based on overall morphological similarity, Platypholis has been merged with Orobanche, but this hypothesis has never been tested with molecular data. Employing maximum likelihood and Bayesian analyses on a family-wide data set (two plastid markers, matK and rps2, and three nuclear markers, ITS, phyA and phyB) as well as on an ITS data set focusing on Orobanche s. str., it is shown that P. boninsimae Maxim. is phylogenetically closely linked to or even nested within Orobanche s. str. This position is supported both by morphological evidence and by the newly obtained chromosome number of 2n = 38, which is characteristic for the genus Orobanche s. str.
分子系统发育研究极大地增进了我们对非光合寄生列当属植物（列当属及相关属，列当科）系统发育关系的理解，但仍有少数属未被研究。其中之一是宽翅列当属，其唯一的物种——小笠原宽翅列当，仅分布于日本东南约1000公里处的小笠原群岛（即 Bonin 群岛）。基于整体形态相似性，宽翅列当属已被并入列当属，但这一假说从未用分子数据进行过验证。通过对全科数据集（两个叶绿体标记，matK 和 rps2，以及三个核标记，ITS、phyA 和 phyB）以及聚焦于狭义列当属的 ITS 数据集进行最大似然法和贝叶斯分析，结果表明小笠原宽翅列当在系统发育上与狭义列当属紧密相连，甚至嵌套于其中。这一位置得到了形态学证据以及新获得的2n = 38染色体数的支持，2n = 38是狭义列当属的特征染色体数。
