A phylogenetic study of Chinese Polygonatum (Polygonateae, Asparagaceae)

Abstract

Polygonatum Mill., which consists of more than 60 species are mainly distributed in eastern Asia, especially China and Japan, has received considerable attention from plant taxonomists. Nevertheless, there are still gaps in our knowledge of this genus, especially concerning those species that are endemic to China and which have often not been included in previous studies. Here, we re‐evaluate the taxonomy of 28 Chinese Polygonatum species with emphasis on molecular evidence. Phylogenetic analyses were carried out on sequence data from four plastid DNA regions: atpB‐rbcL, matK, rbcL and rps16, using maximum parsimony and Bayesian approaches. Analyses of the combined datasets of the four regions revealed that: 1) Chinese Polygonatum are monophyletic at the current level of sampling; 2) three major lineages in Polygonatum are well supported and largely correlated with cytological and morphological characters; 3) our results, along with the results of previous works support that P. simizui is a synonym of P. odoratum, and 4) Polygonatum cirrhifoliodes is shown to be distinct from P. cirrhifolium.

Comparative Analysis of Chloroplast Genome and New Insights Into Phylogenetic Relationships of Polygonatum and Tribe Polygonateae

“…More recent molecular phylogenies based on one to several genes have suggested that the Polygonatum could be divided into three groups (Meng et al, 2014;Floden and Schilling, 2018), recommended that the petA-psbJ plastid gene region is combined with the nuclear ribosomal ITS for Polygonatum identification. However, the phylogenetic position of some species [i.e., P. franchetii Hua, P. alternicirrhosum Hand.-Mzt., P. verticillatum (L.) All., P. punctatum Royle ex Kunth] is in dispute (Meng et al, 2014;Floden, 2017;Floden and Schilling, 2018;Jiao, 2018;Zhao et al, 2019;Xia et al, 2022). Moreover, the current taxonomy of Tribe (Trib.)…”

A new synonym of Polygonatum in China, based on morphological and molecular evidence

“…Verticillata shows variable phyllotaxy and x = 13-15 (Meng et al 2014). This is widely accepted and confirmed by multiple molecular phylogenetic studies (Wang et al 2016;Floden and Schilling 2018;Zhao et al 2019). However, due to hybridisation and polyploidisation in this genus, classification of some species with large morphological variations and wide distribution range remains controversial (Tamura 1990;Tamura 2008;Floden 2015;Floden and Schilling 2018;Zhao et al 2019).…”

“…Tamura et Ogisu from Polygonatum (Tamura et al 1997a) and found the topological difference of Heteropolygonatum and its relative taxa: (1) (Heteropolygonatum + Disporopsis) + Polygonatum and (2) (Heteropolygonatum + Polygonatum) + Disporopsis (Tamura et al 1997b). Later, the former case was supported by Meng et al (2014) and Wang et al (2016), whereas the latter one was supported by Floden and Schilling (2018) and Zhao et al (2019). The genus Polygonatum was divided into three sections, based on four chloroplast molecular markers, leaf arrangement and basic chromosome number: (1) Polygonatum sect.…”

Pollen micromorphology of eastern Chinese Polygonatum and its role in taxonomy by using scanning electron microscopy

“…Based on intensive field investigations in recent years, a total of 30 Polygonatum species samples from different species of various distinct populations were examined for these analyses. Specimens were correctly identified compressed, dried, and preserved, then placed on the standard herbarium sheet following the previously published protocol (Bahadur et al, 2019; Zhao, Zhou, & He, 2019). The voucher specimens were deposited in the herbarium of Anhui Normal University (ANUB).…”