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Sequences of nuclear ribosomal DNA internal (ITS) and external (ETS) transcribed spacers were used to generate a phylogeny of Acacia Mill. s.str. (synonyms: Acacia subg. Phyllodineae (DC.) Seringe; Racosperma Mart.). This study included 109 exemplar taxa from all seven sections recognised in previous classifications, and represents the largest sampling of diversity for molecular phylogenetics of Acacia s.str. undertaken so far. Four main clades were identified from the combined dataset of ITS and ETS using parsimony and Bayesian analyses. Two of these clades consist mostly of uninerved phyllodinous taxa assigned to sect. Phyllodineae. One clade includes taxa related to A. victoriae and A. pyrifolia, and the second comprises taxa in the A. murrayana species group. These taxa occur predominantly in semi-arid and arid regions. Relationships also resolve the previously identified Pulchelloidea clade, which includes members of sects. Pulchellae, Alatae, Phyllodineae and Lycopodiifoliae. A large clade with limited phylogenetic resolution was also identified (the \"p.u.b. clade\"). This is an assemblage of plurinerved and uninerved phyllodinous taxa and also bi-pinnate taxa from sect. Botrycephalae. Clades are discussed with reference to morphological characters, and while some morphological states are correlated with clades, including seedling ontogeny, inflorescence and phyllode nerves, clear synapomorphies remain to be identified. Traditional classifications of Acacia s.str. are artificial and a preliminary informal classification based on phylogenetic relationships within Acacia s.str. is proposed.

The genus Lecidea Ach. sensu lato (sensu Zahlbruckner) includes almost 1200 species, out of which only 100 species represent Lecidea sensu stricto (sensu Hertel). The systematic position of the remaining species is mostly unsettled but anticipated to represent several unrelated lineages within Lecanoromycetes. This study attempts to elucidate the phylogenetic placement of members of this heterogeneous group of lichen-forming fungi and to improve the classification and phylogeny of Lecanoromycetes. Twenty-five taxa of Lecidea sensu lato and 22 putatively allied species were studied in a broad selection of 268 taxa, representing 48 families of Lecanoromycetes. Six loci, including four ribosomal and two protein-coding genes for 315- and 209-OTU datasets were subjected to maximum likelihood and Bayesian analyses. The resulting well supported phylogenetic relationships within Lecanoromycetes are in agreement with published phylogenies, but the addition of new taxa revealed putative rearrangements of several families (e.g. Catillariaceae, Lecanoraceae, Lecideaceae, Megalariaceae, Pilocarpaceae and Ramalinaceae). As expected, species of Lecidea sensu lato and putatively related taxa are scattered within Lecanoromycetidae and beyond, with several species nested in Lecanoraceae and Pilocarpaceae and others placed outside currently recognized families in Lecanorales and orders in Lecanoromycetidae. The phylogenetic affiliations of Schaereria and Strangospora are outside Lecanoromycetidae, probably with Ostropomycetidae. All species referred to as Lecidea sensu stricto based on morphology (including the type species, Lecidea fuscoatra [L.] Ach.) form, with Porpidia species, a monophyletic group with high posterior probability outside Lecanorales, Peltigerales and Teloschistales, in Lecanoromycetidae, supporting the recognition of order Lecideales Vain. in this subclass. The genus name Lecidea must be redefined to apply only to Lecidea sensu stricto and to include at least some members of the genus Porpidia. Based on morphological and chemical similarities, as well as the phylogenetic relationship of Lecidea pullata sister to Frutidella caesioatra, the new combination Frutidella pullata is proposed here.

Lagerstroemia indica L. is a well-known ornamental plant with large pyramidal racemes, long flower duration, and diverse colors and cultivars. It has been cultivated for nearly 1600 years and is essential for investigating the germplasm and assessing genetic variation to support international cultivar identification and breeding programs. In this study, 20 common Lagerstroemia indica cultivars from different varietal groups and flower morphologies, as well as multiple wild relative species, were analyzed to investigate the maternal donor of Lagerstroemia indica cultivars and to discover the genetic variation and relationships among cultivars based on plastome and nuclear ribosomal DNA (nrDNA) sequences. A total of 47 single nucleotide polymorphisms (SNPs) and 24 insertion/deletions (indels) were identified in the 20 L. indica cultivars’ plastome and 25 SNPs were identified in the nrDNA. Phylogenetic analysis based on the plastome sequences showed that all the cultivars formed a clade with the species of L. indica, indicating that L. indica was the maternal donor of the cultivars. Population structure and PCA analyses supported two clades of cultivars, which exhibited significant genetic differences according to the plastome dataset. The results of the nrDNA supported that all 20 cultivars were divided into three clades and most of the cultivars had at least two genetic backgrounds and higher gene flow. Our results suggest that the plastome and nrDNA sequences can be used as molecular markers for assessing the genetic variation and relationships of L. indica cultivars.

The systematization of species in plant taxonomy based on the phylogenetic relationships among them are of utmost importance and also very challenging in large genera. In those, phylogenetic results often may suggest substantially different relationships than previous classifications, and call for large-scale taxonomic revisions. Delimitation of the genus Silene has been and is still somewhat controversial, and recent molecular phylogenetic studies have settled several monophyletic groups that differ substantially from previous taxonomies. The infrageneric taxonomy of Silene s.str. has not been updated as a whole taking the phylogenetic information into account. In this study, we review previous phylogenetic results based on multiple loci, and conducted comprehensive gene tree analyses based on the nrDNA ITS and cpDNA rps16 regions for 1586 and 944 samples representing 415 and 397 species, respectively, including Silene and its allies, as well as a species tree analysis including 262 samples representing 243 species. We sampled representatives from all 44 sections recognized in the most recent global revision of the genus. The results support the recognition of three subgenera, i.e., S. subg. Behenantha, S. subg. Lychnis and S. subg. Silene, which is partly in agreement with previous molecular phylogenetic findings and contradicts all previous traditional classifications. Silene sect. Atocion, with a few annual species showing a narrowdistribution range in the eastern Mediterranean, is treated as incertae sedis because of its uncertain phylogenetic position, possibly due to exceptionally high substitution rates. Silene subg. Lychnis, weakly supported as sister to the other subgenera, splits into three main clades and includes four sections. Silene subg. Behenantha, which forms a possible sister group in relation to S. subg. Silene, is poorly resolved basally and includes a large number of mostly small clades recognized as 18 sections. In S. subg. Silene, 11 sections are recognized, among which four are broadly circumscribed: S. sect. Auriculatae, S. sect. Sclerocalycinae, S. sect. Silene and S. sect. Siphonomorpha. Silene sect. Acutifoliae and S. sect. Portenses are described here as new taxa, whereas new status or newcombinations are proposed for S. sect. Anotites, S. sect. Muscipula, S. sect. Petrocoma, S. sect. Pulvinatae, S. sect. Sclerophyllae and S. sect. Uebelinia. Five new combinations and two new names are proposed for taxa in Silene formerly assigned to Lychnis and Uebelinia. The correct infrageneric nomenclature compatible with the new infrageneric system is provided along with synonymy and type citations. Shortcomings of this study, such as the lack of a morphological diagnostic key and sparse sampling of some large sections, are listed and discussed.

Inoculation of crop plants by non-native strains of arbuscular mycorrhizal (AM) fungi as bio-enhancers is promoted without clear evidence for symbiotic effectiveness and fungal persistence. To address such gaps, the forage legume Medicago sativa was inoculated in an agronomic field trial with two isolates of Funneliformis mosseae differing in their nuclear rDNA sequences from native strains. The inoculants were traced by PCR with a novel combination of the universal fungal NS31 and Glomeromycota-specific LSUGlom1 primers which target the nuclear rDNA cistron. The amplicons were classified by restriction fragment length polymorphism and sequencing. The two applied fungal inoculants were successfully traced and discriminated from native strains in roots sampled from the field up to 2 yr post inoculation. Moreover, field inoculation with inocula of non-native isolates of F. mosseae appeared to have stimulated root colonization and yield of M. sativa. Proof of inoculation success and sustained positive effects on biomass production and quality of M. sativa crop plants hold promise for the role that AM fungal inoculants could play in agriculture.

Genome skimming has the potential for generating large data sets for DNA barcoding and wider biodiversity genomic studies, particularly via the assembly and annotation of full chloroplast (cpDNA) and nuclear ribosomal DNA (nrDNA) sequences. We compare the success of genome skims of 2051 herbarium specimens from Norway/Polar regions with 4604 freshly collected, silica gel dried specimens mainly from the European Alps and the Carpathians. Overall, we were able to assemble the full chloroplast genome for 67% of the samples and the full nrDNA cluster for 86%. Average insert length, cover and full cpDNA and rDNA assembly were considerably higher for silica gel dried than herbarium-preserved material. However, complete plastid genomes were still assembled for 54% of herbarium samples compared to 70% of silica dried samples. Moreover, there was comparable recovery of coding genes from both tissue sources (121 for silica gel dried and 118 for herbarium material) and only minor differences in assembly success of standard barcodes between silica dried (89% ITS2, 96% matK and rbcL) and herbarium material (87% ITS2, 98% matK and rbcL). The success rate was > 90% for all three markers in 1034 of 1036 genera in 160 families, and only Boraginaceae worked poorly, with 7 genera failing. Our study shows that large-scale genome skims are feasible and work well across most of the land plant families and genera we tested, independently of material type. It is therefore an efficient method for increasing the availability of plant biodiversity genomic data to support a multitude of downstream applications.

A two-marker combination of plastid rbcL and matK has previously been recommended as the core plant barcode, to be supplemented with additional markers such as plastid trnH–psbA and nuclear ribosomal internal transcribed spacer (ITS). To assess the effectiveness and universality of these barcode markers in seed plants, we sampled 6,286 individuals representing 1,757 species in 141 genera of 75 families (42 orders) by using four different methods of data analysis. These analyses indicate that (i) the three plastid markers showed high levels of universality (87.1–92.7%), whereas ITS performed relatively well (79%) in angiosperms but not so well in gymnosperms; (ii) in taxonomic groups for which direct sequencing of the marker is possible, ITS showed the highest discriminatory power of the four markers, and a combination of ITS and any plastid DNA marker was able to discriminate 69.9–79.1% of species, compared with only 49.7% with rbcL + matK; and (iii) where multiple individuals of a single species were tested, ascriptions based on ITS and plastid DNA barcodes were incongruent in some samples for 45.2% of the sampled genera (for genera with more than one species sampled). This finding highlights the importance of both sampling multiple individuals and using markers with different modes of inheritance. In cases where it is difficult to amplify and directly sequence ITS in its entirety, just using ITS2 is a useful backup because it is easier to amplify and sequence this subset of the marker. We therefore propose that ITS/ITS2 should be incorporated into the core barcode for seed plants.

The nuclear ribosomal locus coding for the large subunit is represented in tandem arrays in the plant genome. These consecutive gene blocks, consisting of several regions, are widely applied in plant phylogenetics. The regions coding for the subunits of the rRNA have the lowest rate of evolution. Also the spacer regions like the internal transcribed spacers (ITS) and external transcribed spacers (ETS) are widely utilized in phylogenetics. The fact, that these regions are present in many copies in the plant genome is an advantage for laboratory practice but might be problem for phylogenetic analysis. Beside routine usage, the rDNA regions provide the great potential to study complex evolutionary mechanisms, such as reticulate events or array duplications. The understanding of these processes is based on the observation that the multiple copies of rDNA regions are homogenized through concerted evolution. This phenomenon results to paralogous copies, which can be misleading when incorporated in phylogenetic analyses. The fact that non-functional copies or pseudogenes can coexist with ortholougues in a single individual certainly makes also the analysis difficult. This article summarizes the information about the structure and utility of the phylogenetically informative spacer regions of the rDNA, namely internal- and external transcribed spacer regions as well as the intergenic spacer (IGS).

• Premise of the study: Genome survey sequences (GSS) from massively parallel sequencing have potential to provide large, cost-effective data sets for phylogenetic inference, replace single gene or spacer regions as DNA barcodes, and provide a plethora of data for other comparative molecular evolution studies. Here we report on the application of this method to estimating the molecular phylogeny of core Asparagales, investigating plastid gene losses, assembling complete plastid genomes, and determining the type and quality of assembled genomic data attainable from Illumina 80–120-bp reads. • METHODS: We sequenced total genomic DNA from samples in two lineages of monocotyledonous plants, Poaceae and Asparagales, on the Illumina platform in a multiplex arrangement. We compared reference-based assemblies to de novo contigs, evaluated consistency of assemblies resulting from use of various references sequences, and assessed our methods to obtain sequence assemblies in nonmodel taxa. • Key results: Our method returned reliable, robust organellar and nrDNA sequences in a variety of plant lineages. High quality assemblies are not dependent on genome size, amount of plastid present in the total genomic DNA template, or relatedness of available reference sequences for assembly. Phylogenetic results revealed familial and subfamilial relationships within Asparagales with high bootstrap support, although placement of the monotypic genus Aphyllanthes was placed with moderate confidence. • CONCLUSIONS: The well-supported molecular phylogeny provides evidence for delineation of subfamilies within core Asparagales. With advances in technology and bioinformatics tools, the use of massively parallel sequencing will continue to become easier and more affordable for phylogenomic and molecular evolutionary biology investigations.

Plants of the genera Phrynium and Stachyphrynium traditionally used as ethnomedicine or for wrapping sticky rice dumpling in the tropical and south subtropical Asia, have a long history of ethnobotanical use. China represents the northernmost distribution of Marantaceae in Asia. Due to the notably similar leaf morphology between these genera, herbarium specimens are frequently misidentified, especially during the vegetative stages. Their morphological uniformity and unclear interspecific genetic relationships pose significant challenges to taxonomic classification and species identification. To date, systematic taxonomic revisions and phylogeny of their indigenous species remain lacking. In this study, we conducted comparative chloroplast genomes analyses of seven Phrynium and two Stachyphrynium species in China. The chloroplast genomes exhibited conserved structure, gene content, gene order and codon usage bias, but diverged in genomes size and the SC/IR boundaries. Four variable regions were identified as potential molecular markers for species identification. Phylogenetic analyses using CDS and nrDNA strongly support Phrynium and Stachyphrynium in China as two distinct monophyletic groups, with Phrynium subdivided into two clades. These findings advance our understanding of their molecular relationships and provide critical insights for identification, utilization, and conservation as medicinal plants. Finally, we describe and illustrate the new species Phrynium pyramidale Y. Tong & Z. Y. Lin.