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Societal Impact Statement\ud Many economically, culturally, and historically important apple cultivars are triploids, which have three copies of each chromosome instead of the more typical two copies in diploids. Despite their prevalence and importance, there have been conflicting reports regarding their origin and their ability to beget diploids. New genetic analysis methodologies outlined in this study have clarified the genetic origin of triploid apple cultivars and suggest that triploidy has been a dead end in historic apple pedigrees. The specific results of this study have resolved the pedigrees of many cultivars, including the famous English cultivar Cox's Orange Pippin and the oldest known US cultivar Roxbury Russet.\ud \ud Summary\ud In apple (Malus × domestica), most cultivars are diploid, though a sizeable number are triploids, which tend to be stronger growing, more robust, and bear larger fruit. However, triploidy is also associated with strongly reduced fertility. Some recorded pedigrees for historical apple cultivars include triploids as parents of diploids, despite this reputation of poor fertility. This information, coupled with some initiatives using triploids in breeding efforts, result in confusion about how possible or common it is for triploids to be parents of diploid offspring. To date, no studies have systematically evaluated and identified pedigrees of triploid apple cultivars to resolve these contradictions.\ud Here, we describe a method to make triploid genotype calls using Illumina Infinium single nucleotide polymorphism (SNP) array data through a novel Python script: ploidyClassifier. SNP data for 219 unique triploids was compared alongside 2498 unique diploid apple accessions to conduct pedigree reconstruction.\ud Unreduced gamete-donating parents were identified for over half of the triploid accessions. From those, reduced gamete-donating parents were identified for nearly half. Full or partial pedigrees for many classic triploids were uncovered, including that of the oldest known American cultivar, ‘Roxbury Russet’. All tested pedigrees from literature that listed triploids as parents of diploids were deemed false, including that of the well-known ‘Cox's Orange Pippin’, whose previously unreported second parent was also identified here as ‘Rosemary Russet’.\ud These results together suggest that historic triploids are mostly or solely the product of diploid parentage and that triploidy has been a dead end in historic apple pedigrees.

Chrysophyceae are a diverse group of planktonic protists widely distributed in freshwater. They encompass a variety of orders, whereby heterotrophy has evolved independently in several phylogenetic lineages. Therefore, closely related taxa evolved that developed different feeding strategies (photo-, mixo-, heterotrophy). In high-throughput sequencing studies, the Chrysophyceae were usually addressed as a group rather than split in individual phylogenetic orders. Also because of the close relationship of the distinct nutritional strategies, no functional statements were made about nutritional patterns. Based on an extensive phylogenetic tree and phylogenetic placement, we link OTU diversity of Chrysophyceae from 218 freshwater lakes with phylogenetic affiliations. This provides information on the relative importance of lineages affiliated with different nutrition modes. Our study demonstrates that Chrysophyceae are one of the most common groups in freshwaters. We found Chrysophyceae in 213 out of 218 sample sites across Europe and in several sites they belong to the most commonly retrieved taxa. Ochromonadales and a Chrysosacca-Apoikiida clade (including Apoikiida, Chrysosaccales, Chrysastrella) are the most widespread Chrysophyceae groups and show a high degree of OTU diversity. Most detected and assignable OTUs were affiliated with mixotrophic Chrysophyceae. Niche width differs only slightly between members of different clades and between the different trophic modes. We found several OTUs within the Ochromonadales, Synurales, and Chrysosacca-Apoikiida clade, that show a wide distribution and large tolerance ranges concerning ecophysiological factors.

PREMISE Recent, rapid radiations present a challenge for phylogenetic reconstruction. Fast successive speciation events typically lead to low sequence divergence and poorly resolved relationships with standard phylogenetic markers. Target sequence capture of many independent nuclear loci has the potential to improve phylogenetic resolution for rapid radiations. METHODS Here we applied target sequence capture with 353 protein-coding genes (Angiosperms353 bait kit) to Veronica sect. Hebe (common name hebe) to determine its utility for improving the phylogenetic resolution of rapid radiations. Veronica section Hebe originated 5-10 million years ago in New Zealand, forming a monophyletic radiation of ca 130 extant species. RESULTS We obtained approximately 150 kbp of 353 protein-coding exons and an additional 200 kbp of flanking noncoding sequences for each of 77 hebe and two outgroup species. When comparing coding, noncoding, and combined data sets, we found that the latter provided the best overall phylogenetic resolution. While some deep nodes in the radiation remained unresolved, our phylogeny provided broad and often improved support for subclades identified by both morphology and standard markers in previous studies. Gene-tree discordance was nonetheless widespread, indicating that additional methods are needed to disentangle fully the history of the radiation. CONCLUSIONS Phylogenomic target capture data sets both increase phylogenetic signal and deliver new insights into the complex evolutionary history of rapid radiations as compared with traditional markers. Improving methods to resolve remaining discordance among loci from target sequence capture is now important to facilitate the further study of rapid radiations.

Endophytic fungi are known to be present in roots of salt marsh plants, but their ecological role in this symbiosis is still largely unknown. Generally considered parasitic or saprophytic, they may still be mutualistic, at least under certain circumstances. Among salt marsh plants,Salicorniaspp. are recognized as particularly salt-tolerant and their frequent colonization by root endophytes has also been reported. This study aimed to investigate whether the inoculation ofSalicorniawith different root endophytes isolated from field-collectedSalicorniaaffects biomass production, nutrient uptake and photosynthesis (assessed via chlorophyll fluorescence). In addition, we investigated whether fungal inoculation confers tolerance to salt stress given that endophytes are suggested to increase salt tolerance and improve plant fitness in other less salt-tolerant plants. The inoculation ofSalicorniawith an isolate of the genusStemphyliumpositively influenced total biomass production and nitrogen concentration in roots at optimum salinity condition (150 mM NaCl). However, under salt stress (650 mM NaCl), no significant effects of fungal inoculation on biomass production and photosynthesis were observed. Further, positive and negative effects of fungal inoculation on nutrient concentrations were observed in roots and shoots, respectively. Our results indicate that different endophytic fungi and their interaction result in distinct fungal species-specific plant growth responses ofSalicorniaunder different growth conditions.

—Species delimitation in Rhododendron subsect. Caroliniana (Ericaceae) has been disputed in the past with one or three species accepted. Here we report a fourth species, R. smokianum, a narrow endemic from the Great Smoky Mountains (Tennessee/North Carolina, USA). It is characterized by short-tubed corollas and small, compact growth. We support our conclusion by phylogenetic analyses of ITS and plastid trnL-F sequence data. The new species is a specialist of open mafic rock slopes and maintains morphological and phenological differences to the related species even in cultivation.

The subcosmopolitan genus Gentianella Moench (Gentianaceae, Swertiinae), with more than 170 currently accepted species in South America alone, is one of the emblematic examples of major and rapid radiations in the Andes. However, the taxonomy of South American Gentianella is far from being resolved. Over a century has passed since the publication of the last comprehensive treatment by Ernst Gilg in 1916. Using flow cytometry, the genome size of 115 accessions of 39 species, of which 37 were from South America, was measured, with the objective to assess the taxonomic utility of that trait. Also, the relationships of genome size with environmental factors such as mean annual temperature and precipitation, as well as the life history traits, habit, reproduction, habitat, and elevational belt were examined. The genome size values of the investigated South American accessions fell into two size classes, ranging from 2C = 7.60 pg to 11.30 pg and from 2C = 16.54 pg to 18.34 pg. The latter size class contained only accessions of G. briquetiana (Gilg) T. N. Ho & S. W. Liu. These accessions, and a further one of G. limoselloides (Kunth) Fabris with an intermediate value of 2C = 14.71 pg, were inferred to be octoploid. Genome size was not correlated with temperature, precipitation, habit, or elevational belt. By contrast, significant differences in genome size between groups were found regarding habitat and reproduction. Furthermore, genome size of one of the informal taxonomic groups of Gilg (Barbatae) differed from that of the remaining groups. However, this finding is of doubtful taxonomic relevance because of inconsistencies in the application of Gilg’s defining criterion of Barbatae, i.e., the presence of trichomes inside the corolla tube. Based on the overall results, it is concluded that genome size is not a taxonomically useful trait in South American Gentianella. Still, the data offer a first view on genome size variation and evolution in this diverse but poorly studied group.

Invasive plant species are a major threat to biodiversity worldwide. Thus, information on their distribution, morphological variation as well as their reaction to ecological parameters are required to adequately evaluate their threat and manage invasions. Plantago major is a cosmopolitan invasive plant species and a possible threat to the local flora in dry grasslands. A multivariate analysis of data acquired from 19 populations of this species across various locations in Iran was used to evaluate the diversity of quantitative and qualitative morphological traits possibly affected by ecological factors to understand its distribution pattern. Morphological traits were variable and depended on the location of observation. Quantitative traits in particular exhibited a higher variation than qualitative traits between populations, with higher diversity in populations from the Central Alborz and Khorasan. Further, populations with higher vegetative growth had relatively lower reproductive fitness, i.e. a trade-off between the number of seeds per individual and vegetative traits. Cluster analysis based on either morphological data or ecological variables were capable to group the populations close to their geographical origins, despite correlation coefficients of ecological variables with morphological traits being mainly non-significant. Our results provide important insights into the variability of P. major and potentially allow inferences on distribution limits in Iran.

Polyploidy is recognized as a mechanism of speciation in plants with cascading effects on biotic interactions. However, a limited number of studies have investigated the effects of polyploidy on the association of plants and microorganisms. Herein, we investigated whether two Salicornia cytotypes (S. europaea – 2x and S. procumbens – 4x) show different root-associated fungal communities. Additionally, we explored the existence of cytotype-specific root anatomical traits, which could influence fungal recruitment and establishment. Salicornia spp. were identified based on their ploidy level. The root-associated fungal microbiome of Salicornia was analyzed using high throughput amplicon sequencing (ITS1 of rDNA) in spring and summer. The following root anatomical traits were investigated: maximum root diameter, periderma thickness, parenchyma thickness, diameter of the vascular cylinder and maximum diameter of parenchyma cells. Our results showed that Shannon diversity and evenness indices were higher in samples of Salicornia procumbens (4x) compared to those of S. europaea (2x), and in summer the root-associated fungal community of S. procumbens (4x) was significantly different from that of S. europaea (2x). The orders Xylariales, Malasseziales and Pleosporales were the most frequent root colonizers in both cytotypes and most of the taxa associated with Salicornia were functionally classified as saprophytes or plant pathogens. Finally, we observed larger periderma and parenchyma layers in S. procumbens (4x) than S. europaea (2x) that may contribute to the observed differences in community composition between the two cytotypes. Our results suggest that differences in ploidy may modulate plant interaction with fungi by affecting species recruitment and microbiome structure. In addition, cytotype-specific root traits may also have the potential to affect differently community assembly in the two cytotypes.

Pollen morphology of six species belonging to genera Ellisiophyllum and Sibthorpia (Plantaginaceae tribe Sibthorpieae) was studied using light and scanning electron microscopy. The data were analyzed in the light of the first phylogenetic analysis including all but one species of the tribe using DNA sequence data from nuclear ribosomal (ITS) and plastid trnL-F region. Pollen grains in representatives of this tribe are 3-colpate, occasionally 3-porate, suboblate to prolate; mainly medium-sized, rarely small. One major pollen type (3-colpate) is recognized in the tribe. Within this pollen type, six subtypes are distinguished based on their exine sculpture, pollen grain size, length of the apertures, and exine thickness. The obtained results confirm that pollen characters are useful for species identification. Palynomorphological data are consistent with the results of the molecular phylogenetic analyses. All studies support a sister relationship of the widespread European Sibthorpia europaea with the widespread South American Sibthorpia repens and a sister relationship of two insular species, the Balearic Sibthorpia africana and the Madeiran Sibthorpia peregrina. Pollen grains in the tribe Sibthorpieae have both reticulate exine sculpture characteristic for representatives of the Russelieae–Cheloneae–Antirrhineae clades of Plantaginaceae, and also nanoechinate sculpture, which is typical for the Veroniceae and Plantagineae clades of that family. Also, in Sibthorpia repens, we observe a possible transition from the colpate type to the porate type typical for taxa of Plantago and Littorella.

Plantago sect. Coronopus contains our two focal species (P. coronopus L., P. crassifolia Forssk.), both with an overall conspicuous bi‐hemispheric distribution range (Mediterranean and Middle Eastern regions in the Northern Hemisphere and South Africa in the Southern Hemisphere). We have evaluated up to 27 morphological characters from 96 herbarium specimens representing five out of seven species of that section that are currently recognised using principal coordinate analysis, linear discriminant analyses, agglomerative clustering, and classification tree analyses, in order to test the current taxonomic concepts of our two focal species. Furthermore, we used 54 individuals representing six out of those seven species of P. sect. Coronopus to construct molecular phylogenetic hypotheses by sequencing nuclear ribosomal DNA from the internal transcribed spacer region (ITS), the plastid trnL‐F region, the plastid intergenic spacer region trnH‐psbA and adopting maximum likelihood and Bayesian inference analyses. In the Northern Hemisphere, an Irano‐Arabian clade initially identified as P. coronopus and shown as distinct in both morphological and phylogenetical terms fits a wider circumscription of P. crypsoides Boiss. due to lack of the prominent short and thick inflorescence scape following Boissier's description. The morphological differences between P. crassifolia from the Mediterranean region and P. crassifolia from South Africa (often named P. carnosa Lam.) were marginal, yet the molecular phylogenetic analyses of both nuclear and plastid markers clearly separated these evolutionary entities. Therefore, we re‐instated the name P. carnosa as the correct name for South African P. crassifolia. Plantago carnosa differs from P. crassifolia by the combination of having stronger woody rootstocks, which are more often branched, by broader leaves (≥1.6 mm wide) and the fact that specimens more often turn brown when dried. Our dataset provides the best sampled phylogenetic hypothesis for P. sect. (and subg.) Coronopus to date, and reveals discordance between nuclear and plastid genealogies within P. sect. Maritima, which requires further investigation.

PREMISE Classification of taxa depends on the quality of inferred phylogenies. Rhododendron, a highly species-rich genus (>1156 species) of woody plants, has a highly debated infrageneric classification, due to its huge diversity, homoplasy in key characters, and incongruence among data sets. We provide a broad coverage of representative species to resolve Rhododendron infrageneric phylogeny and highlight the areas of incongruence. We further investigate the effect of polyploidy and genome size evolution on diversification of Rhododendron. METHODS We generated two plastid and two nuclear loci for 260 Rhododendron species. We analyzed the loci separately as well as concatenated, utilizing both likelihood and Bayesian methods. We tested incongruence both among the data sets and with previous studies. We estimated genome sizes for 125 species through flow cytometry. RESULTS Our results suggest stronger support for larger subgenera; however, the smaller subgenera pose several problems; for example, R. tomentosum (former genus Ledum) occupies incongruent positions based on different DNA regions. The main shift to higher diversification in the genus occurs in the Himalayan/Southeast Asian clade of R. subg. Hymenanthes. We found that polyploidy occurs in almost all subgenera but most frequently within R. subg. Rhododendron sections Rhododendron and Schistanthe. CONCLUSIONS We endorse the recognition of five major clades at the subgeneric level, but a number of species cannot be confidently assigned to these clades due to incongruency. With regard to genome size evolution, results support previous reports that genome sizes of tropical plants are lower than those of colder and temperate regions and that genome downsizing promotes diversification.

Whole genome duplication or polyploidy is widespread among floras globally, but traditionally has been thought to have played a minor role in the evolution of island biodiversity, based on the low proportion of polyploid taxa present. We investigate five island systems (Juan Fernández, Galápagos, Canary Islands, Hawaiian Islands, and New Zealand) to test whether polyploidy (i) enhances or hinders diversification on islands and (ii) is an intrinsic feature of a lineage or an attribute that emerges in island environments. These island systems are diverse in their origins, geographic and latitudinal distributions, levels of plant species endemism (37% in the Galapagos to 88% in the Hawaiian Islands), and ploidy levels, and taken together are representative of islands more generally. We compiled data for vascular plants and summarized information for each genus on each island system, including the total number of species (native and endemic), generic endemicity, chromosome numbers, genome size, and ploidy levels. Dated phylogenies were used to infer lineage age, number of colonization events, and change in ploidy level relative to the non-island sister lineage. Using phylogenetic path analysis, we then tested how the diversification of endemic lineages varied with the direct and indirect effects of polyploidy (presence of polyploidy, time on island, polyploidization near colonization, colonizer pool size) and other lineage traits not associated with polyploidy (time on island, colonizer pool size, repeat colonization). Diploid and tetraploid were the most common ploidy levels across all islands, with the highest ploidy levels (>8x) recorded for the Canary Islands (12x) and New Zealand (20x). Overall, we found that endemic diversification of our focal island floras was shaped by polyploidy in many cases and certainly others still to be detected considering the lack of data in many lineages. Polyploid speciation on the islands was enhanced by a larger source of potential congeneric colonists and a change in ploidy level compared to overseas sister taxa.

Storage ability of D. dumetorum is restricted by a severe phenomenon of post-harvest hardening which starts 72h after harvest and renders tubers inedible. Previous work has only focused on the biochemistry changes affecting the PHH on D. dumetorum. To the best of our knowledge nobody has identified candidate genes responsible for hardness on D. dumetorum. Here, transcriptome analysis of D. dumetorum tubers was performed, 4 months after emergence (4MAE), after harvest (AH), 3 days AH (3DAH) and 14 days AH (14DAH) on four accessions using RNA-Seq. In total between AH and 3DAH, 165, 199,128 and 61 differentially expressed genes (DEGs) were detected in Bayangam 2, Fonkouankem 1, Bangou 1 and Ibo sweet 3 respectively. Functional analysis of DEGs revealed that genes encoding for cellulose synthase A, xylan O-acetyltransferase chlorophyll a/b binding protein 1,2,3,4 and transcription factor MYBP were found predominantly and significantly up-regulated 3DAH, implying that genes were potentially involved in the post-harvest hardening. A hypothetical mechanism of this phenomenon and its regulation has been proposed. These findings provide the first comprehensive insights into genes expression in yam tubers after harvest and valuable information for molecular breeding against the post-harvest hardening. A hypothetical mechanism of this phenomenon and its regulation has been proposed. These findings provide the first comprehensive insights into genes expression in yam tubers after harvest and valuable information for molecular breeding against the post-harvest hardening.

PREMISERhododendron L. (Ericaceae Juss.), is the most species-rich genus of woody flowering plants with > 1000 species. Despite the interest in the genus and numerous previous phylogenetic analysis, the infrageneric classification for the genus is still debated, partly due to its huge diversity, partly due to homoplasy in key characters and partly due to incongruence between phylogenetic markers. Here, we provide a broad coverage of representative species of all Rhododendron subgenera, sections, and most subsections to resolve its infrageneric phylogeny or highlight areas of incongruence, support previous analyses of diversification patterns and establish a relationship between genome size evolution and its diversification.METHODSWe generated sequences of two plastid (trnK and trnL-F) and two nuclear (ITS and rpb2-i) markers for a total of 259 Rhododendron species, and used likelihood and Bayesian statistics to analyze the data. We analyzed the markers separately to discuss and understand incongruence among the data sets and among previous studies.RESULTSWe found that the larger a subgenus, the more strongly it is supported as monophyletic. However, the smaller subgenera pose several problems, e.g., R. subgen. Azaleastrum consists of two sections inferred to be polyphyletic. The main shift to higher diversification in the genus occurred in the Himalayan/SE Asian clade of R. subgen. Hymenanthes. We found that polyploidy occurs in almost all subgenera but most polyploid species are within R. subgen. Rhododendron sections Rhododendron and Schistanthe.CONCLUSIONWhereas previous reports stated that genome sizes of tropical plants are lower than those of colder and temperate regions in angiosperms in general, our study provides evidence for such a shift to small genome-tropical species within a genus. Taken together, we see the merit in the recognition of the five major clades at the sub generic level but given the amount of incongruence a large amount of species cannot be confidently assigned to one of these five clades. Further, genome-wide data will be necessary to assess whether these currently unassignable taxa are independent taxa, assignable to one of the five major clades or whether they are inter-subgeneric hybrids.

From two species of Sutera (S. foetida and S. cordata) (Scrophulariaceae tribe Limoselleae) were isolated three known secoiridoid glucosides (12-14) as well as four iridoid congeners (8-11), all biosynthetically derived from iridodial glucoside (and/or deoxyloganic acid). In addition, two previously unknown compounds were found, namely a terpenoid glucoside lactone (suterolide, 21) and the phenylethanoid glycoside 2''''-O-acetyl-angoroside A (19) as well as verbascoside, echinacoside and tubuloside A(15-17, respectively). Two other species, Jamesbrittenia dissecta and Lyperia antirrhinoides, previously considered to belong to the same genus (Sutera) were shown to be members of two different genera, respectively. Significantly, these two species contained iridoids derived from 8-epi-iridodial (and 8-epideoxyloganic acid), namely aucubin (2), melittoside (3) and acetylharpagide (4). In addition we investigated Melanospermum transvaalense, Lyperia tristis and Microdon dubius likewise from Limoselleae and all of these contained iridoid glucosides from the 8-epi-pathway. Thus, secoiridoid distribution confirms the DNA-based circumscription of Sutera and its sister-group relationship with Manulea. In addition, the results show that the clade including these two genera has a biosynthetic pathway to iridoids fundamentally different from the rest of the tribe and from the whole family Scrophulariaceae.

Veronica species mostly occur in damp fresh water places and in the Mediterranean precipitation regime. Members of this genus grow at different altitudes from sea level to high alpine elevations. They show a high level of polymorphism and phenotypic plasticity in their responses to variations of the environmental factors, a quality that allows them to occur over a wide range of conditions. A group with particular high levels of polymorphism is the group of aquatic Veronica L. species in V. sect. Beccabunga (Hill) Dumort. Here, we attempt to unravel some confusion in the taxonomic complexity in V. section Beccabunga. We recognize 20 taxa in V. sect. Beccabunga and explore the occurrence of V. section Beccabunga, mainly in the Mediterranean basin; especially in Egypt (Nile delta and Sinai), Turkey and Iran with each country containing 10 taxa, from a total of 20 taxa, and characterized by endemics, or near-endemic as Veronica anagalloides ssp. taeckholmiorum. The results confirmed that V. section Beccabunga is divided into three subsections Beccabunga, Anagallides and Peregrinae, which essentially can be differentiated by the absence or presence of a petiole.

Herbarium specimens have become a major source of information in molecular research of biodiversity. However, getting good DNA samples from old herbarium specimens is still a challenge. The purpose of this project is to test different DNA extraction methods for old material from herbaria that often exhibit high DNA fragmentation. We compared a CTAB-based DNA extraction that is followed by a clean-up with paramagnetic beads with a modified NucleoSpin Plant II protocol, based on silica columns. Our results demonstrate that silica column-based methods have less problems with contamination by polysaccharide and polyphenolic compounds. Taking practical considerations into account, the column-based method is better especially when trying to reduce the amount of leaf tissue used since handling with a tiny pellet makes CTAB difficult.

Tidal flats are extremely dynamic habitats in several environmental parameters, which enforces severe selection on their microbial inhabitants. Despite good knowledge of the species present, little is known about the temporal dynamics of their communities. Aim of the study was the investigation of cyanobacterial populations in intertidal flats of the German Wadden Sea and their seasonal- and sediment-type related dynamics of community composition based on next generation sequencing of 16S rRNA fragments. Most of the detected cyanobacterial taxa were present throughout the year, but with changing distribution patterns in different sediment types suggesting migration processes between sediment types during the year. Seasonal as well as tidal changes of environmental conditions and the heterogeneity of the study site concerning grain-size and related parameters created a temporally and spatially highly dynamic ecosystem. Development of microbial mats and community composition was mainly influenced by seasons. The annual mat growth started in spring and reached its maximum in late summer with highest richness as well-stabilized laminated structure. Different grain-sizes provided alternative niches for present taxa when conditions change. Coleofasciculus, Hydrocoleum, and Lyngbya were dominating genera in all sediment types. Βeta diversity of seasonal groups was influenced by the interval between sampling dates.

Epiphytic bromeliads represent a major component of Neotropical forests, but the potential effect of climate change on these plants is unclear. We investigated whether and how bromeliads are affected by the predicted 3°C temperature rise by the end of the century. We conducted growth experiments with 17 epiphytic bromeliad species at different temperatures to determine their fundamental thermal niches. By comparing those with niches for germination, we tested whether ontogenetic niche shift or niche contraction occurs in Bromeliaceae. Applying a classical growth analysis, we assessed the relative importance of the underlying growth components on interspecific variations in growth. Members of two bromeliad subfamilies differed in their response to elevated temperatures: Tillandsioideae may be negatively affected, whereas Bromelioideae moved closer to their thermal optimum. Across different ontogenetic stages, thermal niche characteristics revealed both niche shift and niche contraction. Interspecific variation in growth was driven almost exclusively by net assimilation rate at all temperatures. We conclude that the vulnerability of tropical plants to a future increase in temperature may be more variable than suggested by previous studies. We emphasize the importance of assessing niche breadth over multiple life stages and the need for better microclimatic data to link laboratory data with field conditions.

Four simple iridoid glucosides, three known esters of catalpol, seven esters of aucubin, and two phenylethanoids were isolated from Veronica hookeri (syn. Hebe ciliolata; Plantaginaceae). Of these, none of four aromatic (p-methoxybenzoyl, isovanilloyl, veratroyl, caffeoyl) 6-O-esters of aucubin and 6″-O-benzoyl mussaenosidic acid, had been reported from nature before. Similarly, three simple iridoid glucosides, two esters of 6-O-rhamnopyranosylcatapol, and two phenylethanoid glucosides, as well as 1-O-benzoyl-3-α-glucuronosylglycerol, and 1-O-β-benzoyl rutinoside were isolated from Veronica pinguifolia (syn. Hebe pinguifolia). The compound 3″-O-benzoyl-2″-O-caffeoyl 6-O-rhamnopyranosylcatalpol had not been reported previously. The pattern of the structural features of the iridoid glucosides is overlaid onto the latest molecular phylogenetic framework of Veronica sects. Hebe and Labiatoides, and discussed in the context of evolutionary trends.

The extent of the Pleistocene glaciations in the Patagonian Channel region (southwesternmost South America) and their impact on the vegetation there are largely unknown. Whether the regional flora was wiped out completely (tabula rasa) or survived in ice-free pockets (in situ survival) is still an open question. The molecular imprint of either scenario should still be visible in extant populations. Therefore, DNA sequence data of Oreobolus obtusangulus Gaudich. (Cyperaceae) were analysed. This species is an abundant constituent of Patagonian cushion peat bogs, one of the Patagonian Channel region's major vegetation types. Three hundred and eighty-four individuals from 48 populations were sequenced for two chloroplast (ycf3-psaA and trnQUUG -psbK intergenic spacers) and 14 nuclear loci containing simple sequence repeats (SSRs; microsatellites). Phylogenetic reconstructions and the geographic distribution of genetic diversity revealed that the species was split into three main lineages whose general distributions comprise three separate major regions, that is, south-central Chile, Fuego-Patagonia and the East Patagonian Andes, which probably constitute glacial refugia. Postglacial migration fronts formed a suture zone with high levels of genetic diversity in the Northwest Patagonian Andes, where remnants of a supposedly ancestral lineage were also found to be locally restricted to a single population (Huinay). The heavily glaciated Patagonian Channels were likely recolonized from the northwest, and partly from the south. Although the westernmost Patagonian Channel population (Estero Bachem) harboured private SSR alleles (singletons) and showed slightly elevated genetic diversity, it remained unclear whether this population actually survived in situ. This study helps fill a major gap in reconstructing the Pleistocene vegetation history of West and Andean Patagonia.

Here, we analyzed patterns of taxon richness and endemism of freshwater protists in Europe. Even though the significance of physicochemical parameters but also of geographic constraints for protist distribution is documented, it remains unclear where regional areas of high protist diversity are located and whether areas of high taxon richness harbor a high proportion of endemics. Further, patterns may be universal for protists or deviate between taxonomic groups. Based on amplicon sequencing campaigns targeting the SSU and ITS region of the rDNA we address these patterns at two different levels of phylogenetic resolution. Our analyses demonstrate that protists have restricted geographical distribution areas. For many taxonomic groups the regions of high taxon richness deviate from those having a high proportion of putative endemics. In particular, the diversity of high mountain lakes as azonal habitats deviated from surrounding lowlands, i.e. many taxa were found exclusively in high mountain lakes and several putatively endemic taxa occurred in mountain regions like the Alps, the Pyrenees or the Massif Central. Beyond that, taxonomic groups showed a pronounced accumulation of putative endemics in distinct regions, e.g. Dinophyceae along the Baltic Sea coastline, and Chrysophyceae in Scandinavia. Many other groups did not have pronounced areas of increased endemism but geographically restricted taxa were found across Europe.

Background and Aims The distribution of cytotypes and its potential correlation with environmental variables represent a cornerstone to understanding the origin and maintenance of polyploid lineages. Although many studies have addressed this question in single species at a regional scale, only a few have attempted to decipher this enigma in groups of closely related species at a broad intercontinental geographical scale. Here, we consider ca. 20 species of a diploid-polyploid complex (Veronica subsect. Pentasepalae) of recent and rapid diversification represented in Europe and North Africa to study the frequency and distribution of cytotypes and its relationship with environmental variables. Methods A total of 680 individuals (207 populations) were sampled. Ploidy levels were determined using flow cytometry. Ecological differentiation among cytotypes was tested using climatic and environmental variables related to temperature, precipitation, vegetation and biogeographical region, among others, and by performing univariate and multivariate (constrained PCoA) analyses. Key Results Four ploidy levels (2x, 4x, 6x, 8x) were found and genome downsizing was observed to occur within the group. Plants of different ploidy level are ecologically differentiated, with hexaploids and octoploids occurring in wetter and colder habitats with a higher seasonality than diploids. A south-to-north distribution pattern was found, with diploids occupying southern refugial areas and octoploids being more frequent in northern regions of Europe above the permafrost boundary. Conclusions The distribution of cytotypes can be explained by ecological differentiation, the geographical position of refuge areas during the Quaternary climatic oscillations, as well as by ice and permafrost retreat patterns. The Balkan Peninsula constitutes the most important contact zone between cytotypes. This work provides the first comprehensive ploidy screening within V. subsect. Pentasepalae at a broad scale and indicates that polyploidy and genome downsizing might have contributed to the colonization of new habitats in a recently diverged polyploid complex.

Made available in DSpace on 2020-12-12T00:56:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Hybridization and introgression between species in contact/hybrid zones provide important insight into the genetic and ecological mechanisms of speciation. Cactaceae represents the most important radiation of true succulent angiosperms in the New World. This diversification continues to date, with species experiencing few intrinsic barriers to gene flow and the frequent occurrence of natural hybridization. Here, we used RAD-Seq single-nucleotide polymorphism (SNP) data to investigate the genetic architecture of hybridization in four hybrid zones hosting Melocactus concinnus and four congeneric species (M. ernestii, M. glaucescens, M. paucispinus, and M. zehntneri). Our results revealed that M. concinnus is highly promiscuous in sympatric areas and hybridizes with various species distributed in Morro do Chapéu (Diamantina Plateau, Bahia), eastern Brazil. However, the contemporary genomic introgression among the investigated species is very low (c. 2–5%), confirming that even in the face of hybridization, Melocactus species maintain their genetic integrity. The genomic cline approach showed a large fraction of loci deviating from a model of neutral introgression, where most of the loci are consistent with selection favoring parental genotypes. Our results suggest the occurrence of weak premating but strong postmating reproductive isolation in the analyzed cactus species. Furthermore, as most of the Melocactus species are restricted in distribution, hybridization might negatively affect their integrity if hybrids replace the parental species. Universidade Federal de São Carlos Centro de Ciências Humanas e Biológicas Departamento de Biologia Universidade de São Paulo Faculdade de Filosofia Ciências e Letras de Ribeirão Preto Programa de Pós-graduação em Biologia Comparada Universidade Estadual de Feira de Santana Biotechnology Institute (IBTEC) & Biosciences Institute at Botucatu (IBB) São Paulo State University (UNESP) Institute for Biology and Environmental Sciences Carl von Ossietzky University Biotechnology Institute (IBTEC) & Biosciences Institute at Botucatu (IBB) São Paulo State University (UNESP) FAPESP: 2014/25227-0 FAPESP: 2014/26224-5

The Mediterranean is home to rich variety of aquatic plants. Yet, they are less prominent as other groups of plants in this global hotspot of biodiversity. Veronica sect. Beccabunga is a common member of the semi-aquatic plants in a variety of moist to aquatic habitats in the region. Species numbers vary between two and fifteen with many subspecies and varieties and taxonomic problems. However, most studies involve only regional floras and no global biosystematic analysis is yet available. Here, we present a morphometric and molecular study based on plastid and nuclear ribosomal DNA of the group to provide a phylogenetic framework for the group using 101 specimens of 24 taxa in the morphometric and 65 specimens for 28 taxa. Further, flow cytometry has been used to reveal the ploidy level, especially of the Egyptian endemic taxa. The analyses demonstrate the division in three subsections but fail to resolve further groups within these subsections consistently. Reasons for this lack of resolution are likely a combination of ancient polymorphisms, hybridization and phenotypic plasticity. Especially, the latter two have been shown to be frequent in the group. The study forms the basis for any further study by demonstrating the necessity to analyze the group globally and/or in more in-depth using highly variable molecular markers.

Summary By the end of this century, temperature is predicted to increase by about 6 °C at higher latitudes and about 3 °C in the tropics. Although values predicted for tropical latitudes are lower, rising temperatures in the tropics are likely to have more severe consequences for tropical species that are generally assumed to have narrower climatic niches due to a higher degree of climatic stability and higher niche specialization. Even though temperature affects all ontogenetic stages, the regeneration niche of a species is fundamental for overall niche breadth and hence represents a potential major bottleneck for its distribution. We conducted germination experiments along a range of temperatures with 41 epiphytic bromeliad species to determine thermal germination traits (thermal niche breadth, lower and upper thermal limit, thermal optimum). Based on these traits, we asked whether the thermal germination niche breadth of these species is wide enough to cope with the predicted increase in temperature. Furthermore, we conducted phylogenetic comparative analyses to detect possible niche conservatism of these traits in Bromeliaceae. For 93% of all tested bromeliad species, the predicted mean annual temperature range does not exceed the thermal niche breadth. Moreover, for 85% of all tested species, the current mean annual temperature across the distribution range is well below our estimates of their thermal optima. Furthermore, we found evidence for phylogenetic niche conservatism in most assessed traits. Synthesis. Our report represents an important first step to understand and predict present and future responses of epiphytic bromeliads to global warming. At least with regard to seed germination, epiphytic bromeliads should not be negatively affected by the predicted temperature rise of 3 °C. To the contrary, future temperatures are closer to the thermal optima of most species, potentially leading to an increase in performance. However, since niche conservatism in Bromeliaceae may limit their adaptability to novel climatic conditions, a negative effect of increasing temperatures cannot be completely rejected when considering ontogenetic niche shifts.

Limosella is a small aquatic genus of Scrophulariaceae of twelve species, of which one is distributed in northern circumpolar regions, two in southern circumpolar regions, two in the Americas, one endemic to Australia, and six in tropical or southern Africa or both. The Australasian L. curdieana has always been considered distinct but its close phylogenetic relationships have never been inferred. Here, we investigated the following alternative phylogenetic hypotheses based on comparative leaf morphology and habitat preferences or floral morphology: (1) L. curdieana is sister to the African L. grandiflora; or (2) it is closely related to a group of other African species and the northern circumpolar L. aquatica. We tested these hypotheses in a phylogenetic framework using DNA sequence data from four plastid DNA regions and the nuclear ITS region. These were analyzed using maximum parsimony and Bayesian inference. We obtained moderately resolved, partially conflicting phylogenies, supporting that accessions of L. grandiflora form the sister group to the rest of the genus and that L. curdieana groups with the African taxa, L. africana and L. major, and L. aquatica. Thus, the molecular evidence supports the second hypothesis. A biogeographic analysis suggests an out-of-southern Africa scenario and several dispersal events in the Southern Hemisphere. Past dispersal from southern Africa to Australasia is suggested, yet it cannot be excluded that a route via tropical Africa and temperate Asia has existed.