Molecular phylogeny and divergence times of Onosma (Boraginaceae s.s.) based on nrDNA ITS and plastid rpl32‐trnL_(UAG) and trnH–psbA sequences

Abstract

We analysed 87 species of Onosma (Boraginaceae) from throughout its distribution range to investigate its evolutionary history. Using nrDNA ITS and two plastid (rpl32‐trnL(UAG) and trnH–psbA) markers, we reconstructed phylogenetic relationships within Onosma by conducting maximum parsimony, maximum likelihood, Bayesian, and BEAST analyses. The analyses revealed that Onosma as currently circumscribed is not monophyletic. However, the vast majority of Onosma species appear to belong to a single clade, the so‐called Onosma s.s. Outside of this core clade is a clade containing O. rostellata, a subclade of Sino‐Indian species and Maharanga emodii. Podonosma orientalis (as O. orientalis) appear only distantly related to Onosma but is more closely related to Alkanna, as also suggested in previous molecular studies. The Onosma s.s. clade includes all representatives of O. sect. Onosma, and encompasses three subsections, i.e. Onosma, Haplotricha and Heterotricha, corresponding to asterotrichous, haplotrichous and heterotrichous groups, respectively, but none of these subsections was retrieved as monophyletic. We observed significant incongruence between nuclear and chloroplast phylogenies regarding the phylogenetic status of the heterotrichous group. A dozen of the Iranian haplotrichous species formed a lineage which may not hybridize with asterotrichous species. Divergence time estimates suggested that the early radiation of Onosma s.l. took place at the Oligocene‐Miocene boundary and the diversification within Onosma s.s. occurred during middle to late Miocene and Pliocene.

The complete chloroplast genome sequence of Onosma paniculatum Bur. et Franch. (Boraginaceae), a medicinal plant in Yunnan and its adjacent regions

“…et Franch., possess important medicinal values and are commonly used as the alternative of Arnebiae radix in Yunnan and its adjacent regions, China (Ge et al 2003;Chinese Pharmacopoeia Commission 2015). Until now, most of the studies on Onosma and its related genus have focused on its chemical compositions, morphological taxonomy and molecular phylogeny (Kumar et al 2013;Binzet et al 2018;Nasrollahi et al 2019); whereas, no complete chloroplast genome sequence has been reported in NCBI and other databases. Therefore, we sequenced the complete chloroplast genome sequence of the important medicinal plant, O. paniculatum, as well as reconstructed its phylogenetic tree with other groups based on cp genomes.…”

Two new species and a new record for Onosma L. (Boraginaceae) from northwestern Iran

“…and in turn, to Cystostemon Balf.f. (Weigend et al, 2009, 2013; Cecchi et al, 2011; Chacón et al, 2016, 2019; Nasrollahi et al, 2019). The genus represents a considerable evolutionary radiation, and it has controversial taxonomic treatments (Kolarčik et al, 2010).…”

Metabolic Profiles, Genetic Diversity, and Genome Size of Bulgarian Population of Alkanna tinctoria

“…The authors provided important inferences about the taxonomic and evolutionary relationships of the studied species. Taxonomic markers, like rpl32-trnL (UAG) и trnH–psbA [ 26 ], were applied successfully to different systematic groups, including the species of the Boraginaceae family. Even though these markers have some limitations, they could bring additional insight into the phylogenetic relationships among the Alkanna species.…”