Plastome phylogenomic insights into the Sino‐Japanese biogeography of Diabelia (Caprifoliaceae)

Abstract

Understanding the causes of the Sino-Japanese disjunctions in plant taxa has been a central question in eastern Asian biogeography, with vicariance or long-distance dispersal often invoked to explain such patterns. Diabelia Landrein (Caprifoliaceae; Linnaeoideae) comprises four shrubby species with a Sino-Japanese disjunct distribution. The species diversification time within Diabelia, covering a long geological history of the formation process of the Sino-Japanese flora, dated back to the middle Oligocene, therefore, Diabelia would be an ideal model to elucidate the biogeographic patterns of Sino-Japanese disjunctions with climate fluctuation. In this study, we analyzed complete plastome sequence data for 28 individuals representing all four species of Diabelia. These 28 plastomes were found to be highly similar in overall size (156 243-157 578 bp), structure, gene order, and content. Our phylogenomic analysis of the plastomes supported a close relationship between Diabelia ionostachya (Nakai) Landrein & R.L. Barrett var. wenzhouensis (S.L. Zhou ex Landrein) Landrein from eastern China and Diabelia spathulata (Siebold & Zucc.) Landrein var. spathulata from Japan. Diabelia serrata (Siebold & Zucc.) Landrein was identified as sister to a population of Diabelia sanguinea (Makino) Landrein from Tochigi in central Japan and D. spathulata Landrein, from Toyama, central Japan. Most Diabelia lineages were estimated to have differentiated 8-28 Mya. Our results indicate that two independent vicariance events could explain the disjunction between Japan and Korea in the mid to late Miocene, and between Zhejiang and Japan in the early Miocene.

Origins of cultivars of Chrysanthemum—Evidence from the chloroplast genome and nuclear LFY gene

“…Chloroplast genomes are known to be highly conserved in gene content, organization, and structure among seed plants, are haploid in most flowering plants, and maternally inherited (Jansen et al, 2007; Raubeson et al, 2007; Yang et al, 2013; Zhang et al, 2015, 2017a). Utilization of chloroplast genomes in plant systematics and evolution has become increasingly practical with the decreasing costs of the next‐generation sequencing (Zimmer & Wen, 2015; Rabah et al, 2019; Valcárcel & Wen, 2019; Zhang et al, 2019; Wang et al, 2020). Thus, chloroplast genomes have been used widely as the molecular phylogenetic markers to resolve the maternal ancestors of various hybrid species, such as in Amaranthus L (Viljoen et al, 2018), Lilium L (Gao et al, 2012), Populus L (Zhang et al, 2017a), Tulipa L (Li et al, 2017), Vitis L (Wen et al, 2018, 2020), and tribe Maleae of Rosaceae (Liu et al, 2019).…”

Molecular phylogeny and species delimitation of Stachyuraceae: Advocating a herbarium specimen‐based phylogenomic approach in resolving species boundaries

“…S1, node B), which is coincidentally similar to the biogeographic pattern detected in many other groups, for example, Euptelea Siebold & Zucc (Eupteleaceae) (Cao et al, 2016), Coptis Salisb. (Ranunculaceae) (Xiang et al, 2018), and Diabelia Landrein (Wang et al, 2020). One commonly accepted hypothesis is that exchanges of plants between mainland Asia and the Japanese Islands by way of the East China Sea land bridge occurred due to the drop of sea level during the late Miocene to the early Pliocene.…”

Collections‐based systematics and biogeography in the 21st century: A tribute to Dr. Vicki Funk

“…The development of desert belt in the late Miocene is hypothesized to be important in the subsequent divergence of the north and south lineages within eastern Asia, supporting an emerging important biogeographic pattern in Asia. Wang et al (2020) have tackled another classical biogeographic pattern in eastern Asia—the Sino‐Japanese disjunctions in Diabelia Landrein (four species, Caprifoliaceae; Linnaeoideae). The species diversification within Diabelia dated back to the middle Oligocene, and phylogenomic analysis of the plastomes supported two independent vicariance events leading to the disjunction between Japan and Korea in the middle‐to‐late Miocene and between eastern China (Zhejiang) and Japan in the early Miocene.…”