A comprehensive generic-level phylogeny of the sunflower family: Implications for the systematics of Chinese Asteraceae

The sunflower family (Asteraceae) is the largest and the most diverse flowering plant family, comprising 24 000–30 000 species and 1600–1700 genera. In China, Asteraceae are also the largest family, with approximately 2336 indigenous species in 248 genera. In the past two decades, molecular phylogenetic analyses has contributed greatly to our understanding of the systematics of Asteraceae. Nevertheless, the large-scale analyses and knowledge about the relationships of Chinese Asteraceae at the generic level as a whole are far from complete due to difficulties in sampling. In this study, we presented a three-marker (rbcL, ndhF, and matK) phylogeny of Asteraceae, including 506 genera (i.e., approximately one-third of Asteraceae genera). The study sampled 200 Chinese genera (i.e., approximately 80% of Chinese Asteraceae genera). The backbones of the new phylogeny were largely congruent with earlier studies, with 13 subfamilies and 45 tribes recognized. Chinese Asteraceae were distributed in 7 subfamilies (Mutisioideae, Wunderlichioideae, Carduoideae, Pertyoideae, Gymnarrhenoideae, Cichorioideae, and Asteroideae) and 22 tribes (Mutiseae, Hyalideae, Cardueae, Pertyeae, Gymnarrheneae, Vernonieae, Cichorieae, Doroniceae, Senecioneae, Astereae, Anthemideae, Gnaphalieae, Calenduleae, Inuleae, Athroismeae, Helenieae, Coreopsideae, Neurolaeneae, Tageteae, Millieae, Eupatorieae, and Heliantheae). Chinese Asteraceae lacked 6 basal subfamilies and 23 tribes. Several previously ambiguous relationships were clarified. Our analyses also resolved some unplaced genera within Chinese Asteraceae. Finally, our phylogenetic tree was used to revise the classification for all genera of Chinese Asteraceae. In total, 255 genera, 22 tribes, and 7 subfamilies in China are recognized.     

胶菀属——中国菊科紫菀族的一个新归化属

报道中国东北辽宁省发现的菊科（Asteraceae）紫菀族（Astereae）一个新归化属胶菀属（Grindelia）。它在外形上接近于旋覆花属（1nula）,但区别在于胶菀属花药基部钝,花柱分枝顶端附属物呈披针形或三角形,冠毛鳞片状。依据在中国所采集的标本描述了该属在中国的唯一代表种胶菀（Grindelia squarrosa）的形态特征,并讨论了其自然分布和进入中国的可能途径。     

Evolution of host-parasite relationships of Golovinomyces (Ascomycete: Erysiphaceae) inferred from nuclear rDNA sequences

To understand the evolution of host-parasite relationships in the genus Golovinomyces (Ascomycete: Erysiphaceae), which are obligate parasitic fungi of plants, we investigated the phylogenetic relationships of the genus based on 60 internal transcribed spacer (ITS) and 41 28S rDNA sequences. Five major groups, each represented by isolates from a single tribe of the Asteraceae, were identified in the taxa analyzed in this study. Host plants of four groups were strictly restricted to the Asteraceae. The fifth group, the Lactuceae group, is a large group composed of isolates collected from the tribe Lactuceae of the Asteraceae and all other plant families, which suggests a close affinity between Golovinomyces and the Asteraceae in the early stages of their evolution. Tree topology comparisons between the asteraceous hosts and their parasites suggest that Golovinomyces diverged along with the phylogeny of host tribes Carsueae, Astereae, Heliantheae, and Lactuceae of the Asteraceae. However, a conflict of branching order between the tribe Anthemideae and their parasites suggests that host-jumping has occurred in the tribe Anthemideae. Consequently, we suggest that there are two different phases in the evolutionary history of the host-parasite relationships of Golovinomyces. One phase is divergence in accord with the phylogeny of their hosts, which occurred within the Asteraceae. The another phase is host-jumping, which occurred from the Asteraceae to other families and within the Asteraceae.     

Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae)

All taxa endemic to the Qinghai-Tibet Plateau are hypothesized to have originated in situ or from immediately adjacent areas because of the relatively recent formation of the plateau since the Pliocene, followed by the large-scaled biota extinction and recession caused by the Quaternary ice sheet. However, identification of specific progenitors remains difficult for some endemics, especially some endemic genera. Nannoglottis, with about eight species endemic to this region, is one such genus. Past taxonomic treatments have suggested its relationships with four different tribes of Asteraceae. We intend to identify the closest relatives of Nannoglottis by evaluating the level of monophyly, tribal delimitation, and systematic position of the genus by using molecular data from ndhF gene, trnL-F, and ITS region sequences. We find that all sampled species of Nannoglottis are a well-defined monophyly. This supports all recent taxonomic treatments of Nannoglottis, in which all sampled species were placed in one broadly re-circumscribed genus. Nannoglottis is most closely related to the Astereae, but stands as an isolated genus as the first diverging lineage of the tribe, without close relatives. A tentative relationship was suggested for Nannoglottis and the next lineage of the tribe was based on the ITS topology, the "basal group," which consists of seven genera from the Southern Hemisphere. Such a relationship is supported by some commonly shared plesiomorphic morphological characters. Despite the very early divergence of Nannoglottis in the Astereae, the tribe must be regarded to have its origin in Southern Hemisphere rather than in Asia, because based on all morphological, molecular, biogeographical, and fossil data, the Asteraceae and its major lineages (tribes) are supposed to have originated in the former area. Long-distance dispersal using Southeast Asia as a steppingstone from Southern Hemisphere to the Qinghai-Tibet Plateau is the most likely explanation for this unusual biogeographic link of Nannoglottis. The 23-32-million-year divergence time between Nannoglottis and the other Astereae estimated by DNA sequences predated the formation of the plateau. This estimation is further favored by the fossil record of the Asteraceae and the possible time of origin of the Astereae. Nannoglottis seems to have reached the Qinghai-Tibet area in the Oligocene-Eocene and then re-diversified with the uplift of the plateau. The molecular infragenetic phylogeny of the genus identifies two distinct clades, which reject the earlier infrageneric classification based on the arrangement of the involucral bracts and the length of the ligules, but agree well with the habits and ecological preferences of its current species. The "alpine shrub" vs. "coniferous forest" divergence within Nannoglottis was estimated at about 3.4 million years ago when the plateau began its first large-scale uplifting and the coniferous vegetation began to appear. Most of the current species at the "coniferous forest" clade of the genus are estimated to have originated from 1.02 to 1.94 million years ago, when the second and third uprisings of the plateau occurred, the climate oscillated and the habitats were strongly changed. The assumed evolution, speciation diversity, and radiation of Nannoglottis based on molecular phylogeny and divergence times agree well with the known geological and paleobotanical histories of the Qinghai-Tibet Plateau.     

Comparative plastome analysis of Blumea,with implications for genome evolution and phylogeny of Asteroideae

The genus Blumea (Asteroideae, Asteraceae) comprises about 100 species, including herbs, shrubs, and small trees. Previous studies have been unable to resolve taxonomic issues and the phylogeny of the genus Blumea due to the low polymorphism of molecular markers. Therefore, suitable polymorphic regions need to be identified. Here, we de novo assembled plastomes of the three Blumea species B. oxyodonta, B. tenella, and B. balsamifera and compared them with 26 other species of Asteroideae after correction of annotations. These species have quadripartite plastomes with similar gene content, genome organization, and inverted repeat contraction and expansion comprising 113 genes, including 80 protein‐coding, 29 transfer RNA, and 4 ribosomal RNA genes. The comparative analysis of codon usage, amino acid frequency, microsatellite repeats, oligonucleotide repeats, and transition and transversion substitutions has revealed high resemblance among the newly assembled species of Blumea. We identified 10 highly polymorphic regions with nucleotide diversity above 0.02, including rps16‐trnQ, ycf1, ndhF‐rpl32, petN‐psbM, and rpl32‐trnL, and they may be suitable for the development of robust, authentic, and cost‐effective markers for barcoding and inference of the phylogeny of the genus Blumea. Among these highly polymorphic regions, five regions also co‐occurred with oligonucleotide repeats and support use of repeats as a proxy for the identification of polymorphic loci. The phylogenetic analysis revealed a close relationship between Blumea and Pluchea within the tribe Inuleae. At tribe level, our phylogeny supports a sister relationship between Astereae and Anthemideae rooted as Gnaphalieae, Calenduleae, and Senecioneae. These results are contradictory to recent studies which reported a sister relationship between “Senecioneae and Anthemideae” and “Astereae and Gnaphalieae” or a sister relationship between Astereae and Gnaphalieae rooted as Calenduleae, Anthemideae, and then Senecioneae using nuclear genome sequences. The conflicting phylogenetic signals observed at the tribal level between plastidt and nuclear genome data require further investigation.     

Imbalanced diversification of two Mediterranean sister genera (Bellis and Bellium, Asteraceae) within the same time frame

The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18?C19?million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10?million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today??s species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.).     

(Un)Targeted Metabolomics in Asteraceae: Probing the Applicability of Essential‐Oil Profiles of Senecio L. (Senecioneae) Taxa in Chemotaxonomy

The possible applicability of (un)targeted metabolomics (volatile metabolites) for revealing taxonomic/evolutionary relationships among Senecio L. species (Asteraceae; tribe Senecioneae) was explored. Essential‐oil compositional data of selected Senecio/Senecioneae/Asteraceae taxa (93 samples in total) were mutually compared by means of multivariate statistical analysis (MVA), i.e., agglomerative hierarchical clustering and principal component analysis. The MVA input data set included the very first compositional data on the essential oil extracted from the aerial parts of S. viscosus L. as well as on four different Serbian populations of S. vernalis Waldst . & Kit . (oils from aerial parts and roots; eight samples in total). This metabolomic screening of Senecio/Senecioneae/Asteraceae species (herein presented results and data from the literature) pointed to short‐chain alk‐1‐enes (e.g., oct‐1‐ene, non‐1‐ene, and undec‐1‐ene), with up to now restricted general occurrence in Plantae, as characteristic chemotaxonomic markers/targets for future metabolomic studies of Senecio/Senecioneae taxa. The MVA additionally showed that the evolution of the terpene metabolism (volatile mono‐ and sesquiterpenoids) within the Asteraceae tribe Senecioneae was not genera specific. However, the MVA did confirm plant‐organ specific production/accumulation of volatiles within S. vernalis and suggested the existence of at least two volatile chemotypes for this species.     

毛冠菊属的花粉形态和结构及其系统学意义

对国产菊科特有属的花粉形态和结构进行了光学显微镜、扫描电镜和透射电镜的观察和研究。该属的花粉可以分为圆球形、扁球形和长球形三种类型。种之间的花粉差异主要表现在大小、形状和外壁纺饰的细微变化等方面。与紫菀族、竿里光旋和旋覆共族三个族的代表种的花粉特征进行对比分析,并结合其它生物演化证据,可得取以下结论：（１）支持ａｎｄ－Ｍａｚｚｅｔｔｉ的分类意见,毽炙属应归于紫族中;（２）毛冠菊属的花粉可划分为圆球     

毛冠菊属舌片的微形态特征及其系统学意义

在扫描电镜下观察了毛冠菊属Nannoglottis 8种植物舌片的微形态特征,以探讨其颇有争议的系统位置。所有种类舌片近轴面的细胞为板状,长圆形;径向、切向壁直;外壁特征性突起,外壁中央为纵向皱纹,相邻细胞之间的纹饰无系统连接。这些特征表明毛冠菊属和紫菀族Astereae关系密切,但它在紫菀族内的系统位置可能比较特殊。这些结果和依据ITS序列推测的紫菀族系统发育的结果相吻合。文中还讨论了一些微形态性状的演化趋势以及微形态性状在毛冠菊属部分种类分类中的应用。     

ITS sequence data support a single origin for North American Astereae (Asteraceae) and reflect deep geographic divisions in Aster s.l

The Astereae is the largest tribe of Asteraceae in North America. Morphological diversity suggests that the North American assemblage is polyphyletic as 12 endemic genera, as well as lineages of the genus Erigeron and Conyza (Conyzinae), have been hypothesized to represent at least five separate invasions of North America from Africa, Australia, Eurasia, and South America. This hypothesis was tested with a phylogenetic analysis of nucleotide sequence data from the internal transcribed spacers (ITS) of nuclear ribosomal DNA. Sequences for 62 taxa represent seven outgroup taxa and all major Northern and Southern Hemisphere groups of Astereae, including broad taxonomic and geographic sampling of Conyzinae and Aster s.l. (sensu lato). Parsimony analyses indicate that all North American Astereae are members of a strongly supported clade, and that a diverse group of predominantly woody taxa from Africa, Australia, and South America, are basal Astereae. Furthermore, Aster s.l. is deeply polyphyletic as Eurasian taxa, including Aster s.s. (sensu stricto), appear more closely related to Southern Hemisphere taxa than to North American Aster segregates. There is only low to moderate agreement between proposed higher level Astereae relationships based on ITS and those based either on morphology or chloroplast restriction site data.     

Phylogenetic relationships of New Zealand Asteraceae inferred from ITS sequences

Forty-five sequences from members of all genera of Asteraceae indigenous to New Zealand and 50 published sequences representing the tribal diversity in the family were analyzed to assess the utility of ITS sequences to resolve phylogenetic relationships. Previous studies using chloroplast DNA sequences and morphology provided support for several clades in the Asteraceae, yet the relationships among some of these were uncertain. The results from ITS analysis were largely consistent with these earlier studies. The New Zealand species are included in at least six clades, most of these corresponding to recognized tribes. Our results have also clarified the tribal affinities of a few anomalous genera. Haastia, previously aligned with the Gnaphalieae or the Astereae, is nested in the Senecioneae. Centipeda, previously included in the Astereae or Anthemideae, emerges near the Heliantheae. The relationships of Abrotanella remain unresolved. Received August 8, 2001 Accepted November 6, 2001     

Chemical Constituents and Biological Properties of Genus Doronicum (Asteraceae)

The genus Doronicum, belonging to tribe Senecioneae (Fam. Asteraceae), is found mainly in the Asia, Europe and North Africa. This genus of plant has always been used in traditional medicinal treatments due to the many biological properties shown such as killing parasitic worms and for relieving constipation, as well as to improve heart health, to alleviate pain and inflammation, to treat insect bites, etc. According to the World Flora the genus Doronicum contains 39 subordinate taxa.^[1–3] The purpose of this article, which covers data published from 1970 to 2021 with more than 110 articles, aims to carry out a complete and critical review of the Doronicum genus, examining traditional uses and reporting the antioxidant, antimicrobial, anti-inflammatory and antitumor activity shown from crude extracts or essential oils, and from single isolated compounds. Furthermore, critical considerations of the published data have been highlighted by comparing them with the results obtained from species of other genus belonging to the Asteraceae family.     

Additions to South American Senecioneae (Asteraceae)

Three new Peruvian species belonging to the tribe Senecioneae (Asteraceae) are described, illustrated and their relationships discussed:Gynoxys colanensis, G. lopezii, andPentacalia barbourii.     

毛冠菊属系统位置的核形态证据

首次记载了毛冠菊属2种4居群的核形态资料。两种植物的染色体间期和前期染色体为复杂型 和中间型。狭舌毛冠菊两居群的染色体数目与核型公式为2n＝18＝14m+2sm+2st(2SAT);毛冠菊两居 群的染色体数目与核型公式为2n＝18＝14m+2sm(2SAT)+2st。它们分别代表了整个毛冠菊属的两组 植物,并包含了形态学上最原始的种类,因此,该属的染色体基数可能为x＝9。核形态证据表明毛冠菊属放在紫菀族比放在旋覆花族和千里光族中更为合理。     

Phylogenomics of the hyperdiverse daisy tribes: Anthemideae,Astereae, Calenduleae,Gnaphalieae, and Senecioneae

Asteraceae account for 10% of all flowering plant species, and 35%–40% of these are in five closely related tribes that total over 10 000 species. These tribes include Anthemideae, Astereae, Calenduleae, Gnaphalieae, and Senecioneae, which form one of two enormous clades within Subfamily Asteroideae. We took a phylogenomics approach to resolve evolutionary relationships among these five tribes. We sampled the nuclear and plastid genomes via HybSeq target enrichment and genome skimming, and recovered 74 plastid genes and nearly 1000 nuclear loci, known as Conserved Orthologous Sequences. We tested for conflicting support in both data sets and used network analyses to assess patterns of reticulation to explain the early evolutionary history of this lineage, which has experienced whole‐genome duplications and rapid radiations. We found concordance and conflicting support in both data sets and documented four ancient hybridization events. Due to the timing of the early radiation of this five‐tribe lineage, shortly before the Eocene–Oligocene extinction event (34 MYA), early lineages were likely lost, obscuring some details of their early evolutionary history.     

Chemodiversity of exudate flavonoids in seven tribes of Cichorioideae and Asteroideae (Asteraceae)

Members of several genera of Asteraceae, belonging to the tribes Mutisieae, Cardueae, Lactuceae (all subfamily Cichorioideae), and of Astereae, Senecioneae, Helenieae and Heliantheae (all subfamily Asteroideae) have been analyzed for chemodiversity of their exudate flavonoid profiles. The majority of structures found were flavones and flavonols, sometimes with 6- and/or 8-substitution, and with a varying degree of oxidation and methylation. Flavanones were observed in exudates of some genera, and, in some cases, also flavonol- and flavone glycosides were detected. This was mostly the case when exudates were poor both in yield and chemical complexity. Structurally diverse profiles are found particularly within Astereae and Heliantheae. The tribes in the subfamily Cichorioideae exhibited less complex flavonoid profiles. Current results are compared to literature data, and botanical information is included on the studied taxa.     

CHROMOSOME NUMBERS IN COMPOSITAE. III. SENECIONEAE

Ornduff , Robert (Duke U., Durham, N. C), Peter H. Raven , Donald W. Kyhos , and A. R. Kruckeberg . Chromosome numbers in Compositae. III. Senecioneae. Amer. Jour. Bot. 50(2): 131–139. Illus. 1963.—Chromosome counts are reported for 75 taxa of tribe Senecioneae (Compcsitae) and are listed with a generic summary of previous counts in the tribe. First counts are reported for Bedfordia, Crocidium, Dimeresia, Gamolepis, Lepidospartum, Luina, Peucephyllum, Telradymia, and the first definite count recorded for Euryops. New numbers are added to those previously known in Arnica and Psathyrotes. Intraspecific differences in ploidy-level are reported in 4 North American species of Senecio. Although chromosome numbers are useful as an aid in delimiting some genera of Senecioneae, they are of little use in circumscribing genera peripheral to Senecio, primarily because of the great range of chromosome numbers of that genus. Chromosome numbers support suggestions based on morphological considerations that genera such as Crocidium and Dimeresia do not belong in Senecioneae, whereas chromosome number and morphology of the plants virtually prohibit the removal of such genera as Peucephyllum, Lepidospartum, and Telradymia from Senecioneae, despite the suggestions of several recent authors. It is proposed that the base number for the tribe is 10 and that the tribe originated in the Old World, with subsequent widespread migration and diversification.     

Pyrrolizidine alkaloids and other constituents from Emilia fosbergii Nicolson

Emilia fosbergii is a member of the tribe Senecioneae (Asteraceae), most species of which contain pyrrolizidine alkaloids. Notwithstanding, the phytochemistry of E. fosbergii is poorly understood, and pyrrolizidine alkaloids produced by this species have yet to be characterized. In this work, the presence of 11 pyrrolizidine alkaloids, three caffeoylquinic acid derivatives, and six flavonoids were detected by liquid chromatography coupled to high-resolution mass spectrometry analyses. Pyrrolizidine alkaloids of otonecine, retronecine, and platynecine bases are annotated in different parts of the plant. Furthermore, emiline was isolated, possibly indicating that E. fosbergii has a close phylogenetic relationship with E. coccinea. The chemophenetic implications of the presence of pyrrolizidine alkaloids in E. fosbergii and tribe Senecioneae are discussed.     

The evolution of pyrrolizidine alkaloid biosynthesis and diversity in the Senecioneae

Pyrrolizidine alkaloids are characteristic secondary metabolites of the Asteraceae and some other plant families. They are especially numerous and diverse in the tribe Senecioneae and form a powerful defense mechanism against herbivores. Studies into the evolution of pyrrolizidine alkaloid biosynthesis using Senecio species have identified homospermidine synthase as the enzyme responsible for the synthesis of the first specific intermediate. These studies further indicated that the homospermidine synthase-encoding gene was recruited following gene duplication of deoxyhypusine synthase and that this occurred independently in several different angiosperm lineages. A review of published pyrrolizidine alkaloid data shows that the Senecioneae are characterized by a large qualitative and quantitative variation in pyrrolizidine alkaloid profiles and that these data demonstrate little phylogenetic signal. This suggests that although the first steps of this pathway are highly conserved, the diversification of secondarily derived pyrrolizidine alkaloids is extremely plastic.