Literature 2019

Literature Archive: 2015 | 2016 | 2017 | 2018 | 2019

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31 October 2019

Jones K. E., Fér T., Schmickl R. E., Dikow R. B., Funk V. A., Herrando‐Moraira S., Johnston P. R., Kilian N., Siniscalchi C. M., Susanna A., Slovák M., Thapa R., Watson L. E. & Mandel J. R. 2019: An empirical assessment of a single family‐wide hybrid capture locus set at multiple evolutionary timescales in Asteraceae. – Appl. Pl. Sci. https://doi.org/10.1002/aps3.11295

Abstract:
“Premise: Hybrid capture with high‐throughput sequencing (Hyb‐Seq) is a powerful tool for evolutionary studies. The applicability of an Asteraceae family‐specific Hyb‐Seq probe set and the outcomes of different phylogenetic analyses are investigated here.

Methods: Hyb‐Seq data from 112 Asteraceae samples were organized into groups at different taxonomic levels (tribe, genus, and species). For each group, data sets of non‐paralogous loci were built and proportions of parsimony informative characters estimated. The impacts of analyzing alternative data sets, removing long branches, and type of analysis on tree resolution and inferred topologies were investigated in tribe Cichorieae.

Results: Alignments of the Asteraceae family‐wide Hyb‐Seq locus set were parsimony informative at all taxonomic levels. Levels of resolution and topologies inferred at shallower nodes differed depending on the locus data set and the type of analysis, and were affected by the presence of long branches.

Discussion: The approach used to build a Hyb‐Seq locus data set influenced resolution and topologies inferred in phylogenetic analyses. Removal of long branches improved the reliability of topological inferences in maximum likelihood analyses. The Asteraceae Hyb‐Seq probe set is applicable at multiple taxonomic depths, which demonstrates that probe sets do not necessarily need to be lineage‐specific.”


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31 October 2019

Kirschner J., Štěpánek J., Vašut R. J. & Zámečník J. 2019: New species of Taraxacum native to central Europe. – Preslia 91: 213–230.

Abstract:
Further taxonomic exploration of the genus Taraxacum in central Europe was carried out to update the new identification key to the Czech flora. Within three relatively well explored groups new species were revealed; they are described as Taraxacum aspectabile (T. sect. Erythrosperma), T. clandestinum (T. sect. Palustria) and T. sparsum (T. sect. Celtica s. lat.). Taraxacum aspectabile is known to occur in Austria, Bavaria, Czech Republic and Slovakia, usually in grassland growing on alluvial sands but also in other sandy habitats. It is distinct in having deep castaneous-brown to greyish dark brown achenes with a short cone, and numerous triangular lateral leaf segments. Taraxacum clandestinum is confined to a few sites in the Příbram district, south-central Bohemia and is endemic to Bohemia. This rare species is characterized by a robust involucre with numerous but non-imbricate, ovate to broadly ovate outer phyllaries, the absence of pollen, yellow stigmas, and slender, long achenes with a thin, long cylindrical cone. Taraxacum sparsum is known from numerous localities, all in the lowland eastern part of the Bohemian Chalk Plateau. Its distinctive features include leaves with scattered conspicuous brown-purple spots above, the midvein finely striate purplish adaxially, outer phyllaries patent to patent-arcuate, abaxially dark olivaceous brownish green with a narrow white border, and a relatively thick, ± densely and shortly spinulose achene body, subabrutly narrowing into a short, conical cone. Taraxacum sparsum is a marginal member of T. sect. Celtica, with some resemblance to members of the section Naevosa. All of these species are polyploid agamosperms.

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31 October 2019

Lebeda A., Křístková E., Kitner M., Majeský L., Doležalová I., Khoury C. K., Widrlechner M. P., Hu J.-G., Carver D., Achicanoy H. A. & Sosa C. C. 2019: Research gaps and challenges in the conservation and use of North American wild lettuce germplasm. – Crop Sci 59: 1–20.

Abstract:
“The North American crop wild relatives (CWR) of lettuce (Lactuca L.) represent an underexplored pool of genetic diversity of potential value to breeding programs. The 10 species belong to three different groups: a native clade including at least six allotetraploid species [L. biennis (Moench) Fernald, L. canadensis L., L. floridana (L.) Gaertn., L. graminifolia Michx., L. hirsuta Muhl. ex Nutt., and L. ludoviciana (Nutt.) Riddell], a diploid clade with one species [L. tatarica (L.) C. A. Mey. subsp. pulchella (Pursh) Stebbins], and a clade related to the cultivated taxon (L. sativa L.) with three non-native species (L. saligna L., L. serriola L., and L. virosa L.). In this review, we examine the role of herbarium and genebank holdings in taxonomic and other foundational studies, as well as for germplasm exploration and use. We compile the state of knowledge on the ranges of lettuce CWR in North America, modeling the potential distributions of the species and assessing their ex situ and (for native species) in situ conservation status. We categorize seven of the species as high priority for further conservation and three as medium priority, with none currently considered low priority or sufficiently conserved. Further, we review morphological, phenological, genetic diversity, and pest and disease information with regard to North American species. We conclude by outlining the critical gaps and describing a way forward for addressing challenges in the conservation and use of North American wild lettuce germplasm.”

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31 October 2019

Chaves C. L., Ruas E. A., Ruas C. F., Urtubey E. & Ruas P. M. 2019: Genetic diversity and structure of Hypochaeris catharinensis Cabrera (Asteraceae), an endemic species of Southern Brazil. – Pl. Syst Evol. 305: 675–686.

Abstract:
“The genus Hypochaeris was likely introduced into South America by a unique long-distance dispersal event from an ancestral Northwest African species, with subsequent radiation and diversification throughout the temperate zones of the continent. Hypochaeris catharinensis is an endemic species of Southern Brazil growing mostly in high-elevation grasslands with dry, rocky, and shallow soils. Here, we used nine microsatellite loci and a total sample of 441 individuals to assess genetic variability patterns within and among 13 H. catharinensis populations. The results showed a total of 215 alleles in the nine loci tested, the expected and observed heterozygosities average were 0.31 and 0.43, respectively, and allelic richness varied from 4.09 to 7.23. The levels of allelic richness showed that genetic variability is maintained by gene flow, thus ensuring that these populations are not genetically isolated. We found no correlation between geographic and genetic distances, with high levels of genetic variability within, rather than among, populations. The low levels of genetic structure in the species are consistent with recent evolutionary processes of the Hypochaeris genus in South America; after adaptive radiation and species differentiation, dispersal to similar habitats led to the establishment of new populations. Along with initial founder effects, the existence of gene flow explains the current genetic variation across the H. catharinensis populations. In addition, historic environmental changes reported for Southern Brazil may explain the current clustered distribution of the species.”

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23 September 2019

Chen Y.-S., Xu L.-S. & Ke R. 2019: Nabalus muliensis (Asteraceae, Cichorieae), a new species from China. – Phytotaxa 416: 257–262.

Abstract:
Nabalus muliensis (Asteraceae, Cichorieae), a new species from southwestern Sichuan, China, is described and illustrated. It is the third species of Nabalus occurring in China. The new species is similar to Nabalus tatarinowii in its paniculiform inflorescence, nodding capitula, 3–5 florets, cylindric involucre, achene with unequal ribs and pale brown pappus, but differs by its yellow florets (vs. purple, white or pink), leaf blade lyrate-pinnatilobate (vs. divided with 1–3 pairs of lobes),
and achenes with a 2–3 mm long beak (vs. apex truncate). The new species is considered Endangered (EN) according to the IUCN Red List Categories and Criteria.”

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23 September 2019

Björk C. R. 2019: Overlooked diversity in exotic Taraxacum in British Columbia, Canada. – Botany 97: 329–346.

Abstract:
“In almost all North American literature, including in British Columbia, weedy Taraxacum species have been named as Taraxacum officinale F.H.Wigg and Taraxacum erythrospermum Andrz. ex Besser (or Taraxacum laevigatum DC.). This coarse taxonomic approach ignores great diversity in morphology, ecology, and geographical distributions among the exotic established species. Taxonomic refinement would facilitate floristics and ecological studies when exotic Taraxacum species are involved, and the taxonomy of native Taraxacum must first determine which are and which are not native species, which in turn requires knowledge of sectional identity of any specimen. Exotic Taraxacum specimens were identified to species and taxonomic sections using refined species and sectional concepts that align with taxonomic standards used in the native ranges of the species in Europe. Seven exotic sections and one informally named group are found to be present in British Columbia (Borea, Boreigena, Celtica, Erythrosperma, Hamata, Naevosa, Taraxacum, and the Taraxacum fulvicarpum group). The number of exotic Taraxacum species known to occur in British Columbia to date exceeds 100. A key to the exotic sections of British Columbia Taraxacum is presented and the sections are characterized. Species known to date are listed by their sectional placement. Notes are also presented on distinguishing native from exotic Taraxacum in British Columbia.”

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23 September 2019

Strother J. L. 2019: Sonchus tenerrimus (Asteraceae) in North America north of Mexico. – Madroño 66: 80–83.

Abstract:
“Some reports of Sonchus tenerrimus L. for North America north of Mexico, notably from Alabama and California, are based on misidentified specimens of S. oleraceus L.”

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23 August 2019

Urtubey E. 2019: Hieracium reitzianum (Asteraceae, Cichorieae), a new species from Brazil. – Novon 27: 140–143.

Abstract:
Hieracium reitzianum Cabrera ex Urtubey, a new species of Asteraceae from southeastern Brazil, is described and illustrated. This species is placed within Hieracium L. sect. Hypochaeridiformia (Arv.-Touv. ex Peter) Zahn (Hieracium subg. Chionoracium Sch. Bip.) by the presence of ciliate corolla lobes. It is most readily distinguished from other species of the section by having broadly obovate to suborbicular leaves with rounded to obtuse apices.”

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23 August 2019

Gonnelli V., Gottschlich G. & Zoccola A. 2019: Hieracium racemosum subsp. amideii (Asteraceae), a new hawkweed taxon from Montecristo island (Tuscan archipelago, Italy). – Phytotaxa 406: 294–300.

Abstract:
“A new hawkweed taxon endemic to the insula Montecristo (Tuscan archipelago, Italy), Hieracium racemosum subsp. amideii, is described and illustrated. Information on its distribution, ecology and taxonomic relationship is provided.”
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23 August 2019

Szeląg Z. 2019: Two new species in Hieracium sect. Alpina (Asteraceae) from the Eastern Carpathians in Poland. – Phytotaxa 406: 71–78.

Abstract:
“Two apomictic, polyploid (x=9) species in Hieracium sect. Alpina are described from the Western Bieszczady Mountains, Eastern Carpathians, Poland, and illustrated with photos of the holotypes. These are H. jasiewiczii (4x) which combines the morphological features of H. alpinum and H. bifidum, and H. wojcickii (4x) of presumably hybrid origin between H. alpinum and H. pseudobifidum. Both new species are probably relicts originated from diploid, sexual H. alpinum with a wider primary range covering also the Western Bieszczady Mountains, which presently occurs only in the Romanian and Ukrainian Carpathians.”
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23 August 2019

Szeląg Z. & Vladimirov V. 2019: The species intermediate between Hieracium petrovae and H. olympicum (Asteraceae): a treatment of H. kritschimanum and description of a new species from Greece. –  Phytotaxa 402: 107–113.

Abstract:
Hieracium kritschimanum is neotypified with specimens collected in the type locality in Bulgaria. The etymology and original spelling of the species epithet of H. kritschimanum are clarified. Hieracium pangaeum, which combines the morphological features of H. petrovae and H. olympicum, is described from northern Greece. Both species are illustrated with photos of herbarium specimens. A distribution map of H. petrovae, including its first records from Greece, is provided.”

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23 August 2019

Szeląg Z. 2019: Hieracia balcanica XVII. Hieracium wierzbickii (Asteraceae) a new hybridogenous species from Banat in Romania. – Phytotaxa 399: 279–284.

Abstract:
Hieracium wierzbickii, a new, apomictic, triploid (x = 9) species of presumably hybrid origin between sexual, diploid H. umbellatum and agamospermous, tetraploid H. wiesbaurianum subsp. herculanum, is described from Banat in Southern Romania, and illustrated by a photograph of the holotype. This is the first Hieracium species of the morphological formula H. umbellatum – H. wiesbaurianum.”

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23 August 2019

Orsenigo S., Galasso G. & Bonomi C. 2019: Typification of the name Hypochaeris facchiniana Ambrosi (Asteraceae). – Phytotaxa 391: 264–266.

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23 August 2019

Orsenigo S., Gottschlich G. & Galasso G. 2019: The typification and identity of Hieracium australe Fr. (Asteraceae). – Phytotaxa 388: 207–211.

Abstract:
“The name Hieracium australe Fr. (Asteraceae) is typified by specimens collected on the ancient walls of Sforza Castle in Milan (Italy) by Luigi Fenaroli in 1926 and distributed through the Flora Italica Exsiccata series under the name Hieracium australe Fr. subsp. mediolanense Fenaroli & Zahn. The identity and the taxonomic position of this neglected species is discussed.”

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17 July 2019

Shulha O. & Zidorn C. 2019: Sesquiterpene lactones and their precursors as chemosystematic markers in the tribe Cichorieae of the Asteraceae revisited: An update (2008–2017). – Phytochemistry 163: 149–177.

Abstract:
Ten years after the first overview on sesquiterpene lactones in the Cichorieae tribe of the Asteraceae family, we present an update. This review summarizes all chemosystematically relevant reports on sesquiterpene lactones and their immediate precursors from the Cichorieae (syn.: Lactuceae) tribe of the Asteraceae published between 2008 and 2017 and also includes some corrections to the 2008 review. The number of sesquiterpene lactones and sesquiterpenic acids as immediate precursor of sesquiterpene lactones reported for the Cichorieae has increased from 360 to 475 (+32%) within one decade. The number of known source species increased from 139 to 157 (+13%) and the number of chemosystematic reports (reported compounds per taxon) increased from 838 to 1241 (+48%). Notwithstanding this high interest in sesquiterpene lactones of the Cichorieae, still only from 30 out of 94 currently accepted genera within the Cichorieae at least one sesquiterpene lactone has been reported so far.”

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17 July 2019

Shulha O., Çiçek S. S., Wangensteen H., Kroes J., Mäder M., Girreser J., Jöhrer K., Greil R., Schühly W., Mangoni A., Grauso L., Thiel C. van, Zidorn C. 2019: Lignans and sesquiterpene lactones from Hypochaeris radicata subsp. neapolitana (Asteraceae, Cichorieae). – Phytochemistry 165: 112047.

Abstract:
“Four undescribed lignans and two undescribed sesquiterpenic acids, together with three known compounds (hypochoeroside C, hypochoeroside D, and 5-O-caffeoylshikimic acid) were isolated from the roots of Hypochaeris radicata subsp. neapolitana (Asteraceae, Cichorieae). The lignans were identified as 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranoside, 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranosyl-2′-O-methacrylate, (7S,8R,8′R)-7-(3,4-dihydroxyphenyl)-3′,4′-dihydroxy-7,8,7′,8′-tetrahydronaphtho [8,8′-c]furan-1(3H)-one, and (7S,8R,8′R)-7-(3,4-dihydroxyphenyl)-3′,4′-dihydroxy-8'-(hydroxymethyl)-7,8,7′,8′-tetrahydronaphthalen-8-carboxylic acid. The two sesquiterpenic acids were identified as the ring open precursors of hypochoerosides C and D. Structures were elucidated using NMR and HRMS. Absolute configurations of (7S,8R,8′R)-7-(3,4-dihydroxyphenyl)-3′,4′-dihydroxy-7,8,7′,8′-tetrahydronaphtho [8,8′-c]furan-1(3H)-one and (7S,8R,8′R)-7-(3,4-dihydroxyphenyl)-3′,4′-dihydroxy-8'-(hydroxymethyl)-7,8,7′,8′-tetrahydronaphthalen-8-carboxylic acid were determined using electronic circular dichroism (ECD) spectroscopy. 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranoside was evaluated for its anti-proliferative activity against myeloma cell lines MM1S, U266, and NCI-H929 and showed cytotoxicity at 100 mM against MM1S strain. No neurotoxicity was observed for major compounds 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranoside, hypochoeroside C, and hypochoeroside D in a fluorescence assay measuring neurite outgrowth in dorsal root ganglion (DRG) neurons. Additionally, compounds 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranoside, hypochoeroside C, hypochoeroside D, and hypochoerosidic acid D were quantified in unstressed and drought-stressed plants using HPLC-DAD. Drought-stressed plants were found to contain lower concentrations of the lignan 4-(3,4-dihydroxybenzyl)-2-(3,4-dihydroxyphenyl)tetrahydrofuran-3-carboxy-O-β-D-glucopyranoside and sesquiterpene lactone hypochoeroside C.”

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17 July 2019

Zidorn C. 2019: Bioprospecting of plant natural products in Schleswig-Holstein (Germany) I: Chemodiversity of the Cichorieae tribe (Asteraceae) in Schleswig-Holstein. – Phytochem. Rev. https://doi.org/10.1007/s11101-019-09609-z

Abstract:
“Recent international developments make access to biological resources across international borders more difficult than in the past. Local access to biological resources, including plant natural products, thus becomes more important. In order to evaluate the opportunities to access bioactive natural products in our region, we here start a series of dedicated articles assessing the chemical diversity of plant taxa, native and naturalized, in the region of Schleswig-Holstein, Germany. The region has only a limited biodiversity with about 1500 species of higher plants growing in the wild. Our aims are the following: (1) A complete review of the natural products reported from taxa occurring in Schleswig-Holstein from any part of their distribution range. (2) Proof or disproof, whether these substances are also occurring in populations of the taxa at hand occurring in the wild in Schleswig-Holstein. (3) To establish analytical GLC-MS and/or HPLC-DAD-MS systems to identify and quantify these compounds. (4) Initiation of dedicated efforts to unravel the array of secondary metabolites contained in species from the Schleswig-Holstein region not yet investigated. (5) Search for chemically defined intraspecific taxa, i.e. chemically differing lineages of morphologically indistinguishable plant taxa, by comparing plants from Schleswig-Holstein with plants collected in other regions. The survey into the plant natural products’ chemodiversity of the flora of Schleswig-Holstein begins with a review of the natural products from Schleswig-Holstein members of the Cichorieae tribe of the Asteraceae family. The Cichorieae tribe of the Asteraceae family, which encompasses 94 genera and about 1500 species and innumerous microtaxa worldwide (Kilian et al. in Systematics, evolution and biogeography of the Compositae, IAPT, Vienna, ), is represented by only 17 genera in Schleswig-Holstein: Arnoseris, Chondrilla, Cicerbita, Cichorium, Crepis, Hieracium, Hypochaeris, Lactuca, Lapsana, Leontodon, Picris, Pilosella, Scorzonera, Scorzoneroides, Sonchus, Taraxacum, and Tragopogon. In total, 48 species (50 taxa including the two species with two distinct subspecies each in the region and treating the sections in the hyper-species-rich genus Taraxacum as species here), occur in Schleswig-Holstein. For all of the genera and all but six of the species (Hieracium fuscocinereum, Lactuca macrophylla, Sonchus palustris, and Taraxacum sections Celtica, Hamata, and Obliqua), the array of plant natural products has already been investigated to some degree. However, for only two taxa (Pilosella officinarum and Tragopogon pratensis subsp. minor) also plants from the region of Schleswig-Holstein have been studied and for only very few taxa, such as Cichorium intybus and Taraxacum officinale, all major classes of natural products have been investigated in detail so far.”

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12 July 2019

Mandel J. R., Dikow R. B., Siniscalchi C. M., Thapa R., Watson L. E. & Funk V. A. 2019: A fully resolved backbone phylogeny reveals numerous dispersals and explosive diversifications throughout the history of Asteraceae. – PNAS 116: 14083–14088.

Abstract:
“The sunflower family, Asteraceae, comprises 10% of all flowering plant species and displays an incredible diversity of form. Asteraceae are clearly monophyletic, yet resolving phylogenetic relationships within the family has proven difficult, hindering our ability to understand its origin and diversification. Recent molecular clock dating has suggested a Cretaceous origin, but the lack of deep sampling of many genes and representative taxa from across the family has impeded the resolution of migration routes and diversifications that led to its global distribution and tremendous diversity. Here we use genomic data from 256 terminals to estimate evolutionary relationships, timing of diversification(s), and biogeographic patterns. Our study places the origin of Asteraceae at ∼83 MYA in the late Cretaceous and reveals that the family underwent a series of explosive radiations during the Eocene which were accompanied by accelerations in diversification rates. The lineages that gave rise to nearly 95% of extant species originated and began diversifying during the middle Eocene, coincident with the ensuing marked cooling during this period. Phylogenetic and biogeographic analyses support a South American origin of the family with subsequent dispersals into North America and then to Asia and Africa, later followed by multiple worldwide dispersals in many directions. The rapid mid-Eocene diversification is aligned with the biogeographic range shift to Africa where many of the modern-day tribes appear to have originated. Our robust phylogeny provides a framework for future studies aimed at understanding the role of the macroevolutionary patterns and processes that generated the enormous species diversity of Asteraceae.”

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12 July 2019

Safavi S. R. 2019: Scorzonera tomentosa L. (Asteraceae), a new record for the flora of Iran. – Iran. J. Bot. 25: 40-43.

Abstract:
Scorzonera tomentosa L. is reported for the first time from Iran, it has been collected from Kordestan, NW. of Iran.”

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12 July 2019

Dudáš M. 2019: Taraxacum sect. Erythrosperma in Slovakia. Part I. Addenda to distribution of Taraxacum cristatum. – Thaiszia 29: 51–59.

Abstract:
New distribution data of Taraxacum cristatum (T. scanicum group), described in the year 2005, in Slovakia were recorded. During the intensive study of Slovak dandelions in herbarium collections and field course, additional 22 localities were found. The species has been recorded in 17 phytogeographical districts up to now, with the highest frequency in the western and the southern part of the country, preferring dry and xerothermic steppe grasslands, pastures and dry meadows from the class Festuco-Brometea. The altitudinal maximum in Slovakia, in 668 m a. s. l. was recorded in the Strážovské vrchy Mts. on the top of Mt. Baba. The updated distribution map is attached.

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12 July 2019

Takemori A., Naiki A., Takakura K.-I., Kanaoka M. M., Nishida S. 2019: Comparison of mechanisms of reproductive interference in Taraxacum. – Ann. Bot. 123: 1017–1027.

Abstract:
“Background and Aims: Reproductive interference may reduce fitness of either of the involved species, with potentially important ecological and evolutionary consequences. Except for the effect of shared pollinators on reproductive success, however, mechanisms underlying reproductive interference have been little studied, even though the severity of its impact may depend on the specific mechanism. The aim of this study was therefore to explore the mechanisms of reproductive interference between Taraxacum japonicum (native to Japan) and Taraxacum officinale (alien).

Methods: In a field survey, the association between alien species density and seed set in T. japonicum, and whether pollinator behaviour indicated a preference for the alien, were examined. Effects of heterospecific pollen deposition were measured in a series of hand pollination experiments, including mixed pollination experiments in which the order of application of conspecific and heterospecific pollen was varied. Finally, to investigate hybridization frequency, the parentage of seedlings produced following natural, mixed or heterospecific pollination was compared.
Key Results: Alien species density did not negatively affect native seed set, nor did pollinators appear to have a preference for alien flowers. The hand pollination experiments showed that heterospecific pollen deposition adversely affected native seed set, especially when alien pollen was applied before conspecific pollen. No viable hybrids were found following natural pollination, which suggests that hybridization might be a rare event.
Conclusion:Among the examined mechanisms, heterospecific pollen deposition might have the largest deleterious effect on the native species. This effect is frequency dependent; thus, a positive feedback loop may cause the effect on the population dynamics to increase over time, with the result that the alien might eventually displace the native in a population. Effects of the examined mechanisms on population dynamics should be investigated further to improve understanding of the impact of reproductive interference on the structure of plant communities.”

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29 May 2019

Genç İ. & Fırat M. 2019: Karyological study of the genus Gundelia (Compositae) in Turkey. – Caryologia 72: 45–53.

Abstract:
“Karyotypes in 12 taxa of Gundelia are compared, based on Feulgen-stained somatic metaphase chromosomes. The karyotypes of G. anatolica, G. asperrima, G. cilicica, G. colemerikensis, G. dersim, G. glabra, G. komagenensis, G. mesopotamica, G. munzuriensis and G. vitekii are described for the first time. Karyological analyses indicate relationships among the species with respect to their asymmetry indices. All Gundelia species studied were diploid with 2n = 2x = 18 chromosomes. All karyotypes are symmetrical, consisting of metacentric and submetacentric chromosomes. The submetacentric chromosomes of all the investigated specimens contain a secondary constriction. Three chromosome types were identified according to the position of the secondary constrictions. The chromosomes ranged in size from 2.00 μm to 7.02 μm. The total haploid chromosome length (THL) varied from 24.97 μm (G. asperrima) to 42.56 μm (G. rosea). To determine the karyological relationships among taxa, PCoA (Principal Coordinate Analysis) with six uncorrelated parameters was performed.”

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17 May 2019

Gottschlich G. 2019: Taxonomische und nomenklatorische Änderungen in der Gattung Hieracium für die Neuauflage der "Exkursionflora für Österreich und die gesamten Ostalpen". – Neilreichia 10: 53–68

Abstract:
“Results of preliminary studies on taxonomy and nomenclature of Hieracium (Asteraceae) relating to the next edition of the "Excursion Flora for Austria and all the Eastern Alps" are presented: Hieracium clusii is recognized at specific rank; H. tephrosoma s. lat. is divided into H. tephrosoma s. str. and H. kuekenthalianum; H. duronense is synonymized with H. antholzense; H. pseudinuloides is validated; four new subspecific combinations are made under H. atratum, H. balbisianum, H. cavillieri and H. inuloides; H. variifurcum is combined to Pilosella variifurca; the date of publication of H. cochleare is corrected; and 9 names are lectotypified.”

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17 May 2019

Gottschlich G. 2019: Bisher nicht bekannte oder berücksichtigte Nachweise von Hieracium- und Pilosella taxa in Austria ". – Neilreichia 10: 85–96.

Abstract:
“In preparation of the 4th edition of the "Flora for Austria and all the Eastern Alps", 41 records of Pilosella and Hieracium taxa are published that were not yet known in a federal state of Austria or not considered in the last edition of the excursion flora: Pilosella amaurocephala is new for Austria, 28 records are new for a federal state and 12 records are verifications of rare or old records.”

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9 May 2019

Cho M.-S., Yang J. Y., Yang T.-J. & Kim S.-C. 2019: Evolutionary comparison of the chloroplast genome in the woody Sonchus alliance (Asteraceae) on the Canary Islands. – Genes 10(3): 217.

Abstract:
“The woody Sonchus alliance consists primarily of woody species of the genus Sonchus (subgenus Dendrosonchus; family Asteraceae). Most members of the alliance are endemic to the oceanic archipelagos in the phytogeographic region of Macaronesia. They display extensive morphological, ecological, and anatomical diversity, likely caused by the diverse habitats on islands and rapid adaptive radiation. As a premier example of adaptive radiation and insular woodiness of species endemic to oceanic islands, the alliance has been the subject of intensive evolutionary studies. While phylogenetic studies suggested that it is monophyletic and its major lineages radiated rapidly early in the evolutionary history of this group, genetic mechanisms of speciation and genomic evolution within the alliance remain to be investigated. We first attempted to address chloroplast (cp) genome evolution by conducting comparative genomic analysis of three representative endemic species (Sonchus acaulis, Sonchus canariensis, and Sonchus webbii) from the Canary Islands. Despite extensive morphological, anatomical, and ecological differences among them, their cp genomes were highly conserved in gene order and content, ranging from 152,071 to 152,194 bp in total length. The number of repeat variations and six highly variable regions were identified as valuable molecular markers. Phylogenetic analysis of 32 species in the family Asteraceae revealed the phylogenetic position of the woody Sonchus alliance within the tribe Cichorieae and the sister relationship between the weedy Sonchus oleraceus and the alliance.”

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30 April 2019

Crawford D.J., Moura M., Borges Silva L., Mort M. M. Kerbs B. Schaefer H. & Kelly J. K. 2019: The transition to selfing in Azorean Tolpis (Asteraceae). – Pl. Syst. Evol. 305: 305–317.

Abstract:
Asteraceae have the most endemic species of any flowering plant family in oceanic archipelagos, and these insular endemics display a higher frequency of self-compatibility (SC) compared to mainland composites. However, little attention has focused on the evolution of selfing in situ in islands. The genus Tolpis (Asteraceae) in the Macaronesian archipelagos consists predominantly of self-incompatible (SI) or pseudo-self-compatible plants, with one documented occurrence of the origin of self-compatibility (SC) in the Canary Islands. This study reports SC in two small populations of T. succulenta on Graciosa Island in the Azores. Progeny from the two populations exhibit high self-seed set. Segregation in F2 hybrids between SC and SI T. succulenta indicates that one major factor is associated with breeding system, with SC recessive to SI. Molecular phylogenetic analyses show that SC T. succulenta is sister to SI T. succulenta in the Azores, suggesting that SC originated from SI T. succulenta in the Azores. Plants on Graciosa are morphologically distinct from SI populations of T. succulenta on other islands in the Azorean archipelago, with smaller capitula and lower pollen-ovule ratios, both indicative of the selfing syndrome. The factors that may have favored selfing in these populations are discussed, as are the conservation implications of SC. Finally, the issue of whether the two SC populations are cryptic species worthy of taxonomic recognition is discussed.”

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11 March 2019

Urtubey E. & al. 2019: Systematics of Hypochaeris section Phanoderis (Asteraceae, Cichorieae). – Syst. Bot. Monogr. 106: 1–204.

Abstract:
“This revision treat the 41 South American species of Hypochaeris, plus the northwest African H. angustifolia, all now placed in a single monophyletic section Phanoderis. The New World species constitute subsection Phanoderis, and the single African species comprises subsection Africana. The species in South America represent a challenge in classification; molecular clock investigations suggest that the entire complex diverged approximately within the past 1 million years. From an ancestor in northwestern Africa, similar to the present-day H. angustifolia (the phylogenetic sister-species), have come 41 species in a relatively short geological time. These species are similar genetically; routine DNA sequencing with normal markers provides little differentiation. With Amplified Fragment Length Polymorphism (AFLP) analysis, distinct groups can be resolved, some with very strong statistical support other less so. Species arer morphologically reasonably well defined, but the differences are subtle, requiring field experience for accurate identification of taxa. ... Several new taxa and combinations are presented ...”

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11 March 2019

Uhlemann I., Eggert M., Schiemann J. & Thiele K. 2019: Zum Wiederanbau von Taraxacum koksaghyz (Asteraceae) als Kautschuklieferant in Deutschland. – Kochia 12: 19–35.

Abstract:
“Cultivation of diploid, sexual Taraxacum koksaghyz from Central Asia as rubber producer is re-established in Germany. The invasive capability of this species with regard to the native vegetation is extremely low, as shown in competition experiments in grassland and agricultural fields which led to a complete collapse of T. koksaghyz populations within one year. Hybridization events with native Taraxacum populations were not observed. The early stage of domestication of T. koksaghyz is characterized by an extraordinary morphological variability which is documented.”

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21 February 2019

Mráz P.,  Zdvořák P., Hartmann M., Štefánek M. & Chrtek J. 2019: Can obligate apomixis and more stable reproductive assurance explain the distributional successes of asexual triploids in Hieracium alpinum (Asteraceae)? – Pl. Biol. 21: 227–236.

Abstract:
“Although reproductive assurance has been suggested to be one of the most important factors shaping the differential distributional patterns between sexuals and asexuals (geographic parthenogenesis), it has only rarely been studied in natural populations of vascular plants with autonomous apomixis. Moreover, there are almost no data concerning the putative relationship between the level of apomictic versus sexual plant reproduction on one hand, and reproductive assurance on the other.

We assessed the level of sexual versus apomictic reproduction in diploid and triploid plants of Hieracium alpinum across its distributional range using flow cytometric analyses of seeds, and compared the level of potential and realized seed set, i.e. reproductive assurance, between the two cytotypes under field and greenhouse conditions.

Flow cytometric screening of embryos and endosperms of more than 4,100 seeds showed that diploids produced solely diploid progeny sexually, while triploids produced triploid progeny by obligate apomixis. Potential fruit set was much the same in diploids and triploids from the field and the greenhouse experiment. While in the pollination‐limited environment in the greenhouse apomictic triploids had considerably higher realized fruit set than sexual diploids, there was no significant difference between cytotypes under natural conditions. In addition, sexuals varied to a significantly larger extent in realized fruit set than asexuals under both natural and greenhouse conditions.

Our results indicate that triploid plants reproduce by obligate apomixis, assuring more stable and predictable fruit reproduction when compared to sexual diploids. This advantage could provide apomictic triploids with a superior colonisation ability, mirrored in a strong geographic parthenogenesis pattern observed in this species.”

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14 January 2019

Kim S.-H., Mejías J. A. & Kim S.-C. 2019: Next generation sequencing reveals the complete plastome sequence of newly discovered cliff-dwelling Sonchus boulosii (Asteraceae: Cichorieae) in Morocco. – Mitochondrial DNA Part B 4(1): 164-165.

Abstract:
The complete chloroplast genome sequences of newly discovered cliff-dwelling species of Sonchus, S. boulosii, were reported in this study. The S. boulosii plastome was 152,016 bp long, with the large single copy (LSC) region of 83,988 bp, the small single copy (SSC) region of 18,566 bp, and two inverted repeat (IR) regions of 24,731 bp. The plastome contained 130 genes, including 88 protein-coding, six ribosomal RNA, and 36 transfer RNA genes. The overall GC content was 31.2%. Phylogenetic analysis of 12 representative plastomes within the order Cichorieae suggests that S. boulosii is closely related to S. oleraceus.

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