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In modern plant systematics, target enrichment enables simultaneous analysis of hundreds of genes. However, when dealing with reticulate or polyploidization histories, few markers may suffice, but often are required to be single‐copy, a condition that is not necessarily met with commercial capture kits. Also, large genome sizes can render target capture ineffective, so that amplicon sequencing would be preferable; however, knowledge about suitable loci is often missing. Here, we present a comprehensive workflow for the identification of putative single‐copy nuclear markers in a genus of interest, by mining a small dataset from target capture using a few representative taxa. The proposed pipeline assesses sequence variability contained in the data from targeted loci and assigns reads to their respective genes, via a combined BLAST/clustering procedure. Cluster consensus sequences are then examined based on four pre‐defined criteria presumably indicative for absence of paralogy. This is done by calculating four specialized indices; loci are ranked according to their performance in these indices, and top‐scoring loci are considered putatively single‐ or low copy. The approach can be applied to any probe set. As it relies on long reads, the present contribution also provides template workflows for processing Nanopore‐based target capture data. Obtained markers are further tested and then entered into amplicon sequencing. For the detection of possibly remaining paralogy in these data, which might occur in groups with rampant paralogy, we also employ the long‐read assembly tool Canu. In diploid representatives of the young Compositae genus Leucanthemum, characterized by high levels of polyploidy, our approach resulted in successful amplification of 13 loci. Modifications to remove traces of paralogy were made in seven of these. A species tree from the markers correctly reproduced main relationships in the genus, however, at low resolution. The presented workflow has the potential to valuably support phylogenetic research, for example in polyploid plant groups. [ABSTRACT FROM AUTHOR]

Abstract In modern plant systematics, target enrichment enables simultaneous analysis of hundreds of genes. However, when dealing with reticulate or polyploidization histories, few markers may suffice, but often are required to be single‐copy, a condition that is not necessarily met with commercial capture kits. Also, large genome sizes can render target capture ineffective, so that amplicon sequencing would be preferable; however, knowledge about suitable loci is often missing. Here, we present a comprehensive workflow for the identification of putative single‐copy nuclear markers in a genus of interest, by mining a small dataset from target capture using a few representative taxa. The proposed pipeline assesses sequence variability contained in the data from targeted loci and assigns reads to their respective genes, via a combined BLAST/clustering procedure. Cluster consensus sequences are then examined based on four pre‐defined criteria presumably indicative for absence of paralogy. This is done by calculating four specialized indices; loci are ranked according to their performance in these indices, and top‐scoring loci are considered putatively single‐ or low copy. The approach can be applied to any probe set. As it relies on long reads, the present contribution also provides template workflows for processing Nanopore‐based target capture data. Obtained markers are further tested and then entered into amplicon sequencing. For the detection of possibly remaining paralogy in these data, which might occur in groups with rampant paralogy, we also employ the long‐read assembly tool Canu. In diploid representatives of the young Compositae genus Leucanthemum, characterized by high levels of polyploidy, our approach resulted in successful amplification of 13 loci. Modifications to remove traces of paralogy were made in seven of these. A species tree from the markers correctly reproduced main relationships in the genus, however, at low resolution. The presented workflow has the potential to valuably support phylogenetic research, for example in polyploid plant groups.

Species delimitation—owing to the paramount role of the species rank in evolutionary, ecological, and nature conservation studies—is an essential contribution of taxonomy to biodiversity research. In an 'integrative taxonomy' approach to species delimitation on the diploid level, we searched for evolutionary significant units (the warps and wefts) that gave rise to the polyploid complex of European ox-eye daisies (Leucanthemum; Compositae-Anthemideae). Species discovery and validation methods based on genetic, ecological, geographical, and morphometric datasets were applied to test the currently accepted diploid morpho-species, i.e., morphologically delimited species, in Leucanthemum. Novel approaches were taken in the analyses of RADseq data (consensus clustering), morphometrics of reconstructed leaf silhouettes from digitized herbarium specimens, and quantification of species-distribution overlaps. We show that 17 of the 20 Leucanthemum morpho-species are supported by genetic evidence. The taxonomic rank of the remaining three morpho-species was resolved by combining genealogic, ecologic, geographic, and morphologic data in the framework of von Wettstein's morpho-geographical species concept. We herewith provide a methodological pipeline for the species delimitation in an 'integrative taxonomy' fashion using sources of evidence from genealogical, morphological, ecological, and geographical data in the philosophy of De Queiroz's "Unified Species Concept". [ABSTRACT FROM AUTHOR]

Premise: Most phylogenomic library preparation methods and bioinformatic analysis tools in restriction site–associated DNA sequencing (RADseq)/genotyping‐by‐sequencing (GBS) studies are designed for use with Illumina data. The lack of alternative bioinformatic pipelines hinders the exploration of long‐read multi‐locus data from other sequencing platforms. The Simple Long‐read loci Assembly of Nanopore data for Genotyping (SLANG) pipeline enables locus assembly, orthology estimation, and single‐nucleotide polymorphism (SNP) calling using Nanopore‐sequenced multi‐locus data. Methods and Results: Two test libraries (Leucanthemum spp., Senecio spp.; Compositae) were prepared using an amplified fragment length polymorphism (AFLP)‐based method to reduce genome complexity, then Nanopore‐sequenced, and analyzed with SLANG. We identified 704 and 448 orthologous loci with 12,368 and 10,048 SNPs, respectively. The constructed phylogenetic networks were identical to a GBS network produced using Leucanthemum Illumina data and were consistent with Senecio species circumscriptions based on morphology. Conclusions: SLANG identifies orthologous loci and extracts SNPs from long‐read multi‐locus Nanopore data for phylogenetic inference, population genetics, or phylogeographical studies. Combined with an AFLP‐based library preparation, SLANG provides an easily scalable, cost‐effective, and affordable alternative to Illumina‐based RADseq/GBS procedures. [ABSTRACT FROM AUTHOR]

Abstract Premise Most phylogenomic library preparation methods and bioinformatic analysis tools in restriction site–associated DNA sequencing (RADseq)/genotyping‐by‐sequencing (GBS) studies are designed for use with Illumina data. The lack of alternative bioinformatic pipelines hinders the exploration of long‐read multi‐locus data from other sequencing platforms. The Simple Long‐read loci Assembly of Nanopore data for Genotyping (SLANG) pipeline enables locus assembly, orthology estimation, and single‐nucleotide polymorphism (SNP) calling using Nanopore‐sequenced multi‐locus data. Methods and Results Two test libraries (Leucanthemum spp., Senecio spp.; Compositae) were prepared using an amplified fragment length polymorphism (AFLP)‐based method to reduce genome complexity, then Nanopore‐sequenced, and analyzed with SLANG. We identified 704 and 448 orthologous loci with 12,368 and 10,048 SNPs, respectively. The constructed phylogenetic networks were identical to a GBS network produced using Leucanthemum Illumina data and were consistent with Senecio species circumscriptions based on morphology. Conclusions SLANG identifies orthologous loci and extracts SNPs from long‐read multi‐locus Nanopore data for phylogenetic inference, population genetics, or phylogeographical studies. Combined with an AFLP‐based library preparation, SLANG provides an easily scalable, cost‐effective, and affordable alternative to Illumina‐based RADseq/GBS procedures.

Species delimitation—owing to the paramount role of the species rank in evolutionary, ecological, and nature conservation studies—is an essential contribution of taxonomy to biodiversity research. In an ‘integrative taxonomy’ approach to species delimitation on the diploid level, we searched for evolutionary significant units (the warps and wefts) that gave rise to the polyploid complex of European ox-eye daisies (Leucanthemum; Compositae-Anthemideae). Species discovery and validation methods based on genetic, ecological, geographical, and morphometric datasets were applied to test the currently accepted diploid morpho-species, i.e., morphologically delimited species, in Leucanthemum. Novel approaches were taken in the analyses of RADseq data (consensus clustering), morphometrics of reconstructed leaf silhouettes from digitized herbarium specimens, and quantification of species-distribution overlaps. We show that 17 of the 20 Leucanthemum morpho-species are supported by genetic evidence. The taxonomic rank of the remaining three morpho-species was resolved by combining genealogic, ecologic, geographic, and morphologic data in the framework of von Wettstein’s morpho-geographical species concept. We herewith provide a methodological pipeline for the species delimitation in an ‘integrative taxonomy’ fashion using sources of evidence from genealogical, morphological, ecological, and geographical data in the philosophy of De Queiroz’s “Unified Species Concept”.

We examine how different datasets, including georeferenced hardcopy maps of different extents and georeferenced herbarium specimens (spanning the range from 100 to 85,000 km2) influence ecological niche modeling. We check 13 of the available environmental niche modeling algorithms, using 30 metrics to score their validity and evaluate which are useful for the selection of the best model. The validation is made using an independent dataset comprised of presences and absences collected in a range-wide field survey of Carpathian endemic plant Leucanthemum rotundifolium (Compositae). Our analysis of models' predictive performances indicates that almost all datasets may be used for the construction of a species distributional range. Both very local and very general datasets can produce useful predictions, which may be more detailed than the original ranges. Results also highlight the possibility of using the data from manually georeferenced archival sources in reconstructions aimed at establishing species' ecological niches. We discuss possible applications of those data and associated problems. For the evaluation of models, we suggest employing AUC, MAE, and Bias. We show an example of how AUC and MAE may be combined to select the model with the best performance. [ABSTRACT FROM AUTHOR]

Karyological, flow-cytometric and molecular analyses indicate that the genus Leucanthemum Mill. (Compositae, Anthemideae) is represented in Corsica (Corse) by two species: the tetraploid L. ircutianum DC. and the hexaploid L. corsicum (Less.) DC. The indication of the occurrence of the diploid L. vulgare Lam. on the island and of a tetraploid chromosome number for L. corsicum, given in former treatments of the genus for Corsica, could not be corroborated. AFLP fingerprinting further suggests that the infraspecific taxonomy of L. corsicum with two subspecies (L. corsicum subsp. corsicum and subsp. fenzlii) and three forms (L. corsicum f. corsicum, f. pinnatifidum and f. eschenlohrianum), which is mainly based on differences in the degree of leaf dissection, is not backed by genetic discontinuities. Owing to the observed little variation in leaf dissection within populations in the wild and the constancy of these features under cultivation, we propose the rank of varieties to taxonomically acknowledge these different stages in the broad spectrum of leaf-dissection grades exhibited by L. corsicum. As a consequence, the two new combinations L. corsicum var. eschenlohrianum (Gamisans) Vogt, Hugot & Oberpr. and L. corsicum var. fenzlii (Gamisans) Vogt, Hugot & Oberpr. are proposed. Citation: Oberprieler C., Schinhärl L., Wagner F., Hugot L. & Vogt R. 2019: Karyological and molecular analysis of Leucanthemum (Compositae, Anthemideae) in Corsica. – Willdenowia 49: 411–420. doi: https://doi.org/10.3372 Version of record first published online on 4 December 2019 ahead of inclusion in December 2019 issue. [ABSTRACT FROM AUTHOR]

Chromosome counts suggest that the three varieties of the SE French and NW Italian Leucanthemum vulgare subsp. glaucophyllum (var. glaucophyllum: decaploid; var. esterellense: octoploid; var. subglaucum: hexaploid) deserve acknowledgement as independent species. Here we use AFLP fingerprinting and sequence information from two chloroplast regions (psbA-trnH, rpl16) to gain insight into the evolutionary relationships among those species, along with those with the co-occurring and ecologically similar L. pallens (hexaploid) and the closely related L. ircutianum subsp. leucolepis (tetraploid). Both genetic marker systems reveal a geographical differentiation pattern in L. pallens with the Rhône valley forming a suture zone between the western (SW France, Spain) and eastern (SE France, NW Italy) populations, arguing for the existence of two lineages in the species that may have survived the Last Glacial Maximum (LGM) in refugia on the Iberian and Apennine Peninsulas. Transgressions of this suture zone are observable in the case of the hexaploid L. subglaucum from the Massif Central, which shows genetic relationships to the more eastern decaploid L. glaucophyllum from the Alps Maritimes, and the octoploid L. esterellense from the Esterel Massif (Côte d´Azur), for which relationships to the more western populations of the hexaploids L. pallens and L. subglaucum are observable. The genetic and cytological survey of a mixed stand of L. pallens and L. glaucophyllum on Monte Bignone (Liguria, NW Italy) reveals patterns of recent hybridisation of these two species with intermediate octoploid and nonaploid cytotypes that are, however, genetically distinct from L. esterellense. [ABSTRACT FROM AUTHOR]

Delineating species boundaries in the framework of the multi-species coalescent ( MSC) proves to be a reliable, objective, and reproducible method in an increasing number of studies. However, the underlying model assumes the lack of gene flow after speciation; an assumption which may be frequently violated in plant evolution. This study evaluates the robustness of currently available species delimitation methods implemented in beast ( BFD, BFD*, and dissect) in the closely-knit ox-eye daisy group around Leucanthemum ageratifolium Pau. Comprising five taxa being allopatrically distributed between northern Spain and southern Italy this study group shows signs of hybridization with the widespread and codistributed species Leucanthemum vulgare (Vaill.) Lam. to various extent. As expected, our empirical analyses based on both AFLP fingerprinting and sequence data demonstrate that the robustness of species delimitation results is considerably influenced by the intensity of hybridization among species and the number of hybrid individuals included. Therefore, we set up a methodological pipeline with a first step of identification and subsequent removal of individuals showing admixed genetic patterns caused by actual interbreeding using AFLP-fingerprint and morphometric data, followed by application of different Bayesian MSC species delimitation methods based on the remnant individuals using both AFLP-fingerprint and sequence data (four nuclear markers, five concatenated intergenic spacer regions of the plastid genome). The results argue for acknowledgement of Leucanthemum laciniatum, L. legraeanum, and L. ligusticum as independent species, show the close relationship of L. ageratifolium, L. monspeliense, and L. vulgare, and give rise to the description of three nothospecies new to science. [ABSTRACT FROM AUTHOR]

In this contribution new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, exclusions, and confirmations to the Italian administrative regions for taxa in the genera Asplenium, Bolboschoenus, Botrychium, Chamaerops, Crocus, Galeopsis, Grafia, Helosciadium, Hieracium, Juniperus, Leucanthemum, Lolium, Medicago, Phalaris, Piptatherum, Potamogeton, Salicornia, Salvia, Seseli, Silene, Spiraea, Torilis and Vicia. Rhaponticoides calabrica is proposed as synonym novum of R. centaurium. Furthermore, new combinations in the genera Galatella and Lactuca are proposed. [ABSTRACT FROM AUTHOR]

Polyploidy is considered to be a major source of genetic diversity in plants. Genome duplication has been shown repeatedly to be associated with changes in biotic interactions, but little is known about whether species traits such as herbivore resistance consistently change with increasing ploidy level among closely related plant species. We tested whether larval survival and performance of the specialist root-mining moth Dichrorampha aeratana are influenced by the ploidy level of plant species in the genus Leucanthemum by experimentally infesting 16 different taxa with ploidy levels ranging from diploid to dodecaploid. We found that survival of D. aeratana larvae consistently decreased with increasing ploidy level, irrespective of whether phylogenetic distance among taxa was taken into account or not. The mass of larvae and the proportion of adults emerging from last-instar larvae, however, did not consistently change with increasing ploidy level. Root biomass and dry matter content of the Leucanthemum taxa were neither correlated with ploidy level nor correlated with survival or mass of D. aeratana larvae. In summary, our results provide evidence that in the genus Leucanthemum, resistance to the specialist root herbivore D. aeratana consistently increases with increasing plant ploidy level, but it remains unclear which characteristics associated with polyploidy account for the higher herbivore resistance. [ABSTRACT FROM AUTHOR]

The involvement of economic approaches is increasingly pervasive in conservation practices, from environmental policies to procedures determining the choice of conservation projects. The literature on the ethical weaknesses of economic approaches suggests to question the self-evidence of these interactions. However, economics encompasses a variety of approaches and methods, with unclear ethical underpinnings. This article contributes to these debates through a focused clarification of the ethical presuppositions of monetary valuations methods. This choice reflects that monetary valuation studies are expanding and provide numerous opportunities of interactions with conservation biologists. Identifying and understanding their ethical presuppositions is therefore pivotal for conservation biologists. For that purpose, we provide a glossary of the ethical concepts underpinning the current monetary valuation methods. We show that using a given monetary valuation method commits to endorse specific ethical stances. We then develop a practical case study: the conservation of a population of the endangered plant Leucanthemum burnatii Briq. & Cav. in a semi-natural site in the French Alps. We describe the steps that a conservation biologist could follow to decide whether she should seize opportunities to work with economists implementing monetary valuations in this setting. These stepping stones structure the approach that conservation biologists can deploy to identify the ethical stakes of conservation/economics interactions. This approach can also prove useful for conservation biologists to reflexively clarify their own ethical motivations. By appropriating this approach, conservation biologists can equip themselves to enter public debates to legitimize the usage of scientific results to improve collective decision-making on conservation issues. [ABSTRACT FROM AUTHOR]

We examined the evolutionary history of the diploid representatives of the genus Leucanthemum Mill. (Compositae, Anthemideae), which constitutes an extensive polyploid complex comprising around 41 species with ploidy levels ranging from 2 x to 22 x. The inference of phylogenetic relationships even on the diploid level is complicated in this genus due to the overlay of hybridisation and incomplete lineage sorting processes leading to incongruence among gene trees based on nuclear and plastid sequence information. Species tree and network reconstructions were based on gene trees from nine low-copy nuclear markers and the concatenated sequence information for five intergenic spacer regions of the chloroplast genome, either sequenced by Roche 454 pyrosequencing techniques or traditional Sanger sequencing techniques. Additional phylogenetic information came from multi-locus AFLP-fingerprinting of representative individuals of all diploid taxa under study and the subsequent analysis of AFLP patterns with Bayesian clustering and network reconstruction methods. To distinguish between hybridisation and incomplete lineage sorting, we developed and utilized a new ‘hybrid index’ calculation for individual taxa of the data set, which was compared to a simulated null-distribution assuming the occurrence of incomplete lineage sorting alone for pinpointing taxa with a significant hybrid signal. As a result, two species groups with contrasting patterns of gene flow and/or hybrid speciation signals could be identified in the diploids of Leucanthemum: (a) an early-diverging stock of allopatrically distributed diploid species with a lack of evidence for recent hybridisation events among its members and (b) a more recently radiated taxon assemblage with morphologically less clearly circumscribed taxa and a pronounced signal of gene flow among lineages and several candidate taxa, for which a homoploid hybrid origin may be considered. [ABSTRACT FROM AUTHOR]

Highlights: [•] nrDNA ETS cloned and sequenced for Leucanthemum diploids and polyploids. [•] Hybridisation among some diploid Leucanthemum taxa suggested by ETS polymorphisms. [•] Polyploids of the L. pluriflorum clan are allopolyploids. [•] L. pluriflorum as maternal parent of polyploids confirmed. [•] Niche-modelling suggests L. gallaecicum or L. gaudinii as paternal parent. [Copyright &y& Elsevier]

Background Pollen beetle is a pest that attacks oilseed rape as well as many other brassicaceous crops, garden vegetables and ornamental flowers. The present study was primarily carried out to investigate whether insecticide application in brassicaceous field crops might influence the abundance of pollen beetles in nearby private garden flowers and vegetables. Results At peak emergence of the new generation of pollen beetles, a significantly higher number of beetles were found in flowers, and in window traps, alongside untreated as opposed to alongside treated sections of the winter oilseed rape ( WOSR) field. However, the type of flower played a role in the number of pollen beetles found in the flowers. The presence of pollen beetles in both ornamental and wild flowers was also significantly influenced by the direction of placement of the flowers. No pollen beetle, neither overwintering nor newly emerged, was observed in any of the brassicaceous vegetables placed along the field. Conclusion The number of pollen beetles in the WOSR field strongly influenced the number of pollen beetles in nearby flowers of preference to the beetles, and insecticide treatment with Biscaya (thiacloprid) against pollen beetle in oilseed rape may thus help, indirectly, to protect nearby garden flowers from damage. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background and Aims The genus Leucanthemum is a species-rich polyploid complex from southern and central Europe, comprising 41 species with ploidy ranging from 2x to 22x. The present contribution aims at reconstructing the evolutionary history of a geographically isolated species group (the L. pluriflorum clan) from the north-west Iberian Peninsula comprising the diploid L. pluriflorum, the tetraploids L. ircutianum subsp. pseudosylvaticum and L. × corunnense (a putative hybrid taxon based on crossing between L. pluriflorum and L. merinoi), and the hexaploids L. sylvaticum and L. merinoi. Methods Chromosome number variation (determined flow cytometrically) and sequence variation were analysed for two intergenic spacer regions on the plastid genome (psbA-trnH and trnC-petN) for individuals from 54 populations in combination with amplified fragment length polymorphism (AFLP) fingerprinting of 246 representative individuals from these populations. Key Results Plastid sequence data revealed that all surveyed members of the L. pluriflorum clan possess plastid haplotypes that are closely related to each other and distinctly separated from other Leucanthemum species. AFLP fingerprinting resulted in allopolyploid fragment patterns for most of the polyploid populations, except for the tetraploid L. × corunnense and a further tetraploid population in northern Galicia, which cluster with the diploids rather than with the other polyploids. In silico modelling of (auto)tetraploid AFLP genotypes further corroborates the allopolyploid nature of L. ircutianum subsp. pseudosylvaticum, L. sylvaticum and L. merinoi. Conclusions The present study provides evidence for recognizing one diploid (L. pluriflorum), one autotetraploid (L. corunnense), one allotetraploid (L. pseudosylvaticum) and one allohexaploid (L. sylvaticum with the two geographically and ecologically differentiated subspecies subsp. sylvaticum and subsp. merinoi) in the L. pluriflorum clan. It also has implications for the understanding of biogeographical patterns in the Iberian Peninsula. [ABSTRACT FROM PUBLISHER]

Abstract: In order to assess the effects of polyploidisation on distribution patterns of species in a polyploid complex, we compared potential and actual distribution ranges of representatives from the genus Leucanthemum Mill. (Compositae, Anthemideae), which occur on the Iberian Peninsula with 20 taxa spanning ploidy levels between 2n =2x =18 and 2n =22x =198. Actual distribution ranges of taxa were derived from geo-referenced herbarium specimens by defining buffer circles around the collection localities to account for geographical uncertainties and haphazardness of specimen collecting. Eco-climatologically potential ranges were modelled with the maximum entropy method (Maxent) based on the actual distributions. By comparison of sizes of realised and eco-climatologically potential areas for each taxon we computed taxon-specific overlap indices that express the filling of eco-climatological niches. The correlation between overlap indices and ploidy levels was tested by Spearman''s rank correlation coefficient. We observed a significant negative correlation between ploidy level and sizes of realised distribution ranges and no significant correlation of ploidy level and sizes of potential ranges. Finally, we found that diploid and low-ploidy taxa are filling their potential eco-climatological distribution ranges more exhaustively than highly polyploid taxa. Assuming that ascending polyploidisation is the prevailing mode compared to descending polyploidisation, our results demonstrate that the distribution patterns of members of the Leucanthemum polyploid complex on the Iberian Peninsula are mainly influenced by the age of taxa and not by ecological advantages or disadvantages connected with polyploidy. [Copyright &y& Elsevier]

Abstract: Theory suggests that post-zygotic reproductive isolation of polyploids from their diploid progenitors is often caused by developmental disorder in the endosperm of hybrid seeds. Yet, this so-called triploid block is increasingly recognized to be less strong than initially assumed, indicating that other isolation mechanisms are needed to explain reproductive isolation of polyploids and diploids. In the present study, the extent of inter-ploidy block was quantified based on crossing experiments between closely related diploid, tetraploid, and hexaploid species from the genus Leucanthemum Mill. (Compositae, Anthemideae). Seed set and viability of seeds obtained from inter-cytotype crosses were measured and compared to fertilities of intra-cytotype crosses. Although inter-ploidy block was observed when diploids acted as pollen donors, the main observation was that all inter-ploidy crosses were capable of producing viable offspring. By contrast, flow cytometrical analysis of 233 individuals from natural populations did not reveal the presence of any unambiguous cross-ploidy offspring in the field. Hence, the results of the present study demonstrate that inter-cytotype mating may be rare even though inter-ploidy block is weak. Consequently, it can be assumed that pre-zygotic barriers and reduced fitness of inter-cytotype hybrids play a decisive role in the reproductive isolation of polyploid Leucanthemum species. [Copyright &y& Elsevier]

To reconstruct the evolutionary history of the polyploid southern and central European genus Leucanthemum, comprising 41 species with ploidy levels ranging from 2 x to 22 x, we analysed chloroplast DNA sequence variation ( psbA- trnH and trnL- trnF intergenic spacer regions) of 106 representatives belonging to 30 species and 41 taxa. In an unrooted haplotype network, which shows internal (ancestral) haplotypes that are mainly represented by diploid taxa ( L. gallaecicum, L. gracilicaule, L. halleri, L. laciniatum, L. lithopolitanicum, L. rotundifolium, and L. tridactylites), we identified three major haplotype groups (HTGs) containing diploid and polyploid species. Whereas HTG I contains most of the polyploid taxa of the genus, with a single diploid species from the SW Alps ( L. virgatum), HTG II consists of four diploid ( L. burnatii, L. gaudinii, L. graminifolium, and L. vulgare) and six polyploid species, and HTG III comprises one diploid ( L. pluriflorum) and three polyploid species endemic to the NW part of the Iberian Peninsula. We also further found evidence for recurrent formation of at least three polyploid taxa (i.e., L. delabrei, L. ircutianum subsp. cantabricum, and L. pallens). [ABSTRACT FROM AUTHOR]

Overwintering container-grown perennial plants is often necessary during their production. Rooted vegetative cuttings potted at the beginning of the growing season and rooted vegetative cuttings potted at the beginning of the previous growing season, were exposed to -2, -5, -8, -11, and -14C (28, 23, 18, 12, 7F) in January then returned to a greenhouse kept at 3 to 5C (37 to 41F). In June, plan were assessed using a visual rating scale (1 = dead, 3-5 = increasing salable quality) and dry weight of foliage regrowth. For Geranium x cantabrigiense 'Karmina', studied for one year, age did not affect either rating or dry weight. For Sedum 'Matrona', studied for two years, age had no effect on dry weight but ratings were higher for two-year-old plants than one-year-old plants in the first year and higher for one-year-old plants than two-year-old plants in the second year. For Leucanthemum x superbum 'Becky', studied for two years, age affected both rating and dry weight, which were higher for one-year-old plants. Of the cultivars studied, overwintering one-year-old, container-grown plants resulted in more growth and higher quality than overwintered two-year-old plants. [ABSTRACT FROM AUTHOR]

In order to clarify the origin of the wide-spread tetraploid Leucanthemum ircutianum and the hexaploid L. adustum, both found in the alpine and dealpine parts of central Europe together with the diploid L. vulgare, we carried out a genetic analysis based on the distribution of amplified fragment length polymorphism (AFLP) fragments in populations of these three taxa, both in the northwestern Alps (Allgäu region, south Germany and adjacent parts of Austria) and the Franconian Jura (vicinity of Regensburg, Bavaria, Germany). Statistical analyses based on AFLP fragments (principal co-ordinate analysis, PCoA; analysis of molecular variance, AMOVA; Bayesian analysis of population structure, BAPS) suggest that neither of the polyploids is of autopolyploid origin based on L. vulgare, but rather are allopolyploids with the second (maternal) diploid parent still unknown. [ABSTRACT FROM AUTHOR]

The article offers information on Leucanthemum xSuperbum and related daisies. Shasta daisies are known for their bright white, yellow-eyed flowers. It was introduced by Luther Burbank in 1901, name taken from the snowy peaks of Mount Shasta in Northern California. Shasta daisies prefer fertile well drained soils in full sun and are intolerant of wet and poorly drained soils. It also examines the growth and development of daisies Amelia and Becky, which were especially floriferous and robust.

Twenty-two chromosome counts of 19 taxa in the tribe Anthemideae of the family Asteraceae are reported from north-east Anatolia, Turkey. The taxa belong to the subtribes Achilleinae (four Achillea taxa), Anthemidinae (five Anthemis taxa), Artemisiinae (two Artemisia species), Leucantheminae (one Lecanthemum species), Matricariinae (two Tripleurospermum species) and Tanacetinae (five Tanacetum taxa). Six counts are new reports, seven are not consistent with previous counts, and the remainder are confirmations of very limited previous data. Most of the populations of Anthemideae studied have the basic number x = 9, with ploidy levels ranging from 2 x to 7 to 8 x, but dysploidy is also present, with one diploid species, Artemisia austriaca, having x = 8. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 203–211. [ABSTRACT FROM AUTHOR]

The effects of arbuscular mycorrhizal colonization of Leucanthemum vulgare on parasitism of a leaf-mining insect was studied in a field and a laboratory experiment. In the field, parasitism of Chromatomyia syngenesiae by Diglyphus isaea was lower on mycorrhizal plants, compared with plants where the association was reduced. A laboratory experiment, in which L. vulgare was inoculated with three species of AM fungi, showed that the effects on parasitism rates were mycorrhizal species-dependent. Some fungal combinations increased parasitism, some decreased it, while others had no effect. It is concluded that the most likely cause of these differences is plant size, with parasitoid searching efficiency being reduced on the larger plants, resulting from certain mycorrhizal species combinations. However, a mycorrhizal effect on herbivore-produced plant volatiles cannot be ruled out. [ABSTRACT FROM AUTHOR]

Invasive plants can alter the function and structure of ecosystems resulting in social, economic, and ecological damage. Effective methods to reduce the dominance of invasive plants are needed. The present study was aimed at modeling the invasive species Leucanthemum vulgare Lam. in the rangelands of the Namin region in northwest Iran, as well as predicting the habitat connectivity of this species to detect areas with high habitat connectivity. Modeling of potential habitats was performed using logistic regression (LR) and maximum entropy (MaxEnt); the ensemble map which resulted from these was used to predict habitat connectivity using the electrical circuit method. Topography (elevation, slope, and aspect), climate (precipitation and temperature), and soil (acidity, electrical conductivity, soil texture, calcium, magnesium, sodium, phosphorus, potassium, organic carbon, organic matter, saturation percentage, and total neutralizing value) were used in this study. The presence and absence points of the L. vulgare were recorded using a stratified-random sampling method by means of a global positioning system. Soil samples were collected at a depth of 0 to 30 cm where L. vulgare was present and also where it was absent. According to the results, in LR, the variables of temperature, phosphorus, organic matter, and sand and in the MaxEnt, the variables of sand, total neutralizing value (TNV), and silt were the most influential factors on the distribution of L. vulgare. The appraisal of the MaxEnt performance and the precision of the model prediction were 0.97. The Kappa indices for the predicted map obtained from the LR and MaxEnt models were 0.80 and 0.73, respectively. The models' evaluation indicated that both models were able to predict the distribution of L. vulgare habitats with a high level of accuracy; however, LR was more reliable. According to the LR prediction, 9.91% (10,556.25 ha) of the Namin region was attacked by L. vulgare. Connectivity assessment showed that the current density spread of L. vulgare continued from the northeast of the Namin region toward the southeast. On the other hand, the higher current density spread was demonstrated in the eastern region (rangelands adjacent to Fandoghlu forests), and other rangelands which are more threatened by the invasion of L. vulgare. Identifying sites exposed to invasive species can help implement programs to prevent invasive species from invading areas where management and prevention should be implanted to prevent and/or reduce the spread., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

A cytological survey of Leucanthemum species in North Africa has shown that they are all diploid with a somatic chromosome number of 2n = 18. New counts are reported for 8 species and 1 subspecies. 11 taxa were used in a crossing programme and the results show a good agreement between phenetic distance based on morphological characters and genetic differentiation as expressed in the ability of the species to hybridize. A strong barrier to gene exchange exists between European and North African species. Bagging experiments showed that the North African species comprise a self-incompatible group of cytogenetically related species. [ABSTRACT FROM AUTHOR]

The taxonomic arrangement and the karyological analysis of 166 populations of Leucanthemum demonstrates the existence of 5 taxa for Czechoslovakia; they are grouped provisionally into L. rotundifolium (W. K.) DC. (2n = 18) and the polyploid complex L. vulgare Lam. with 'subsp. vulgare' (2n = 18), 'subsp. alpicola' (2n = 18), 'subsp. ircutianum' (2n = ± 36) and 'subsp. pannonicum' (2n = ± 54). B-chromosomes have not been traced in diploids but have turned up in great numbers in tetraploid (21%) and hexaploid populations (20%). Their presence is not apparent from external characters. Diploids and polyploids evidently are selfsterile. [ABSTRACT FROM AUTHOR]