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Understanding the maintenance and shift in reproductive strategies is a fundamental question in evolutionary research. Although many efforts have been made to compare different reproductive strategies, the association between reproductive strategies and lineage divergence is largely unknown. To explore the impact of different reproductive strategies on lineage divergence, we investigated the evolution of clonality in Saxifraga sect. Irregulares+Heterisia. By integrating several lines of evidence, we found that the loss of clonality in Irregulares+Heterisia was associated with a progressive increase in diversification rate and intraspecific morphological diversity but with a reduction in species distribution range. Our findings provide insights into the ecological and evolutionary effects of different reproductive strategies, suggesting the necessity of integrating clonality into ecological and evolutional research. [ABSTRACT FROM AUTHOR]

Background: Accurate species delimitation is fundamental for testing evolutionary theory and provides essential implications for conservation management. The arctic-alpine genus Saxifraga L. (Saxifragaceae) is taxonomically complex and many species have not been critically assessed. The taxonomic and phylogenetic status of Saxifraga lancangensis Y.Y.Qian, considered as a synonym of Saxifraga mengtzeana Engl. & Irmsch. in previous studies, is re-evaluated in light of new evidence presented here. Results: Evidence from morphological comparison and sequencing of plastid genome indicate that S. lancangensis belongs to Saxifraga sect. Irregulares Haw., and is closely related to Saxifraga geifolia Balf.f., and S. mengtzeana. However, S. lancangensis can be diagnosed by its petals with red and clawless base, leaf blade orbicular and leaf margin shallowly dentate. Conclusions: The morphological and molecular evidence support the resurrection of S. lancangensis as a distinct species. An updated morphological description based on protologue and fresh material, diagnostic characters, and original photographs of the resurrected species are presented. [ABSTRACT FROM AUTHOR]

A novel bibenzyl derivative, hydrangchin (1) and ten known compounds (2–11) were isolated from the stems of Hydrangea chinensis Maxim. (Saxifragaceae). The structure of the novel bibenzyl derivative was characterized on the basis of spectral analysis. [ABSTRACT FROM AUTHOR]

Bergenia ciliata (Haw.) Sternb. is a perennial medicinal herb distributed in Indian Himalayan Region (IHR). A total of eight populations of B. ciliata were collected from diverse locales of IHR, and 17 EST-SSR markers were used in this study. The present study revealed moderate genetic diversity at the locus level with the mean number of alleles (Na = 7.823), mean number effective of alleles (Ne = 3.375), mean expected heterozygosity (He = 0.570), and mean Shannon’s diversity index (I = 1.264). The MSR (He = 0.543, I = 1.067) and DRJ populations (He = 0.309, I = 0.519) revealed the highest and lowest genetic diversity at the population level, respectively. AMOVA analysis showed that 81.76% of genetic variation was within populations, 10.55% was among populations, and 7.69% was among the regions. In addition, a moderate to high level of differentiation was found among the populations (FST = 0.182), which could be indicative of low to moderate gene flow (Nm = 0.669) in the B. ciliata populations. UPGMA and PCoA analysis revealed that eight populations could be differentiated into two groups, while the structure analysis of the 96 individuals differentiated into three groups. The Mantel test showed a positive relationship between genetic and geographical distance. The findings of this study will provide the development of conservation and germplasm management strategies for this valuable medicinal species. [ABSTRACT FROM AUTHOR]

Based on the results of single factor experiments, response surface methodology was used to optimize the extraction conditions of flavonoids from Penthorum chinense Pursh (PCF). The optimal extraction conditions were the ratio of liquid to material 22 mL/g, ethanol concentration 68%, extraction temperature 82 °C, and extraction time 2.2 h, respectively. Under these optimized conditions, the PCF yield was 10.72%, which closely agreed with the predicted value (10.75%). In addition, PCF significantly scavenged DPPH radical, hydroxyl radical and superoxide radical in vitro. In the in vivo assays, PCF enhanced the resistance of Caenorhabditis elegans against heat stress, which might be attributed to PCF increased the activities of catalase (CAT) and superoxide dismutase (SOD), and decreased the level of malondialdehyde (MDA). In summary, these results suggested that the optimized extraction was a very effective method to extract PCF and the PCF could be explored as a potential antioxidant for medicine and function food. [ABSTRACT FROM AUTHOR]

Extinction of biodiversity due to human activities is a severe global problem. In Europe, however, only a few plant species died out so far. We investigated a dubious, disregarded taxon- Saxifraga oppositifolia subsp. amphibia-which became extinct in the 1960s. It exclusively occurred in a specific niche, namely in seasonally flooded waterside bank vegetation around Lake Constance in Germany and Switzerland. It has either been interpreted as a glacial relict or as a recent dealpine taxon. Using herbarium material, we conducted phylogenetic analyses based on ITS and cpDNA sequence variation. The taxon shared a chloroplast haplotype of S. oppositifolia, which is mainly distributed in the Alps, favouring the dealpine hypothesis. Nuclear data revealed several paralogous copies nested inside S. oppositifolia, most of which, however, differed from other S. oppositifolia accessions including those from the vicinity of Lake Constance. The oldest mean stem node ages of these ITS copies date between 0.91 and 0.28 my. Contradicting cpDNA, this may indicate that this saxifrage was a distinct taxon and possibly a relict originating in Middle Pleistocene glaciations. If so, the present study exemplifies that arctic-alpine plants survived in specific niches at low altitudes during interglacials and that corresponding taxa with a limited distribution are especially prone to extinction. [ABSTRACT FROM AUTHOR]

The diversification of phytophagous insects is often attributed to diverging processes of host plant specialization onto different, often closely related, host plants. Some insect clades have diversified by specializing not only on different plant species but also on different plant parts of the same hosts. This is the case in Greya moths (Prodoxidae) where both Greya obscura and G. politella are tightly linked to host plants of the genus Lithophragma (Saxifragaceae). We assess how these species differ in their choice of plants and use of plant parts. Previous work showed that strong local host specialization in G. politella is mediated by floral scent variation among Lithophragma species. Here, we identify geographic variation in host plant use in the close relative G. obscura, relate the emerging patterns to previous studies of geographic variation in host use in G. politella and evaluate potential processes underlying the variation among and within species. First, we show that G. obscura also uses floral chemistry to locate hosts but that additional plant cues must be involved in deciding whether to oviposit on a plant, because females did not discriminate against chemically different host species in no-choice trials. We also found that, although all known populations of G. politella oviposit only in flowers, all G. obscura populations examined here distributed their eggs among both floral and scape tissues both in the field and in laboratory experiments. The distribution of eggs among plant parts, however, varied among moth populations, and also depended on the Lithophragma species they attacked. Together, these results show the potential for phytophagous insect species and populations to diverge in use of plant parts as part of the process of speciation and adaptation. These two layers of specialization enhance the potential for subsequent diversification in phytophagous insect lineages. [ABSTRACT FROM AUTHOR]

Cecidophyopsis mites are important pests in all cultivation regions of Ribes causing bud galls and sterility. Despite their economic importance, the knowledge on Cecidophyopsis species infesting Ribes in various areas of the world is still deficient. The present study was carried out to identify Cecidophyopsis species occurring in Latvia on cultivated and wild Ribes, to assess their host range and gain insight into the genetic diversity of these insufficiently studied pests by use of multiplex PCR, rDNA sequences and morphological characters. Cecidophyopsis alpina, C. aurea, C. spicata and C. selachodon were detected to occur in all surveyed habitats. For the first time, C. alpina was identified on blackcurrants and redcurrants, and C. aurea on redcurrants, blackcurrants and alpine currants. The presence of C. ribis was not confirmed with molecular tools during this study. Phylogenetic analyses confirmed the presence of four Cecidophyopsis species identified by multiplex PCR. A close phylogenetic relatedness was found for C. aurea and C. alpina, and for C. ribis and C. spicata highlighting the necessity for additional studies. Our findings suggest a need to consider also other Cecidophyopsis species besides C. ribis in breeding programs for host resistance to mites. [ABSTRACT FROM AUTHOR]

We used RAPD markers to study the population genetic structure and diversity of Saxifraga rosacea subsp. sponhemica, a rare Central European endemic rock plant with a highly disjunct distribution. Because of strong isolation current gene flow between populations is very low or absent. However, an isolation by distance pattern of genetic differentiation suggested historical gene flow during the last glaciation when suitable habitats for S. sponhemica were much more abundant. In most populations, considerable genetic variability has been preserved due to the longevity of S. sponhemica. Our results suggest that long-lived plant species can maintain historic genetic patterns despite small size and strong isolation of populations. Several RAPD loci were identified to be non-neutral and their frequencies correlated with climatic gradients, indicating natural selection. Adaptive genetic variation could be important for adaptation to environmental changes like ongoing climate change. The taxon does not appear to be genetically threatened in the short term, but populations are threatened by habitat destruction. The establishment of new populations in suitable habitats with seeds from the same region may be a suitable conservation measure avoiding potential maladaptation due to local adaptation. [ABSTRACT FROM AUTHOR]

Aceriphyllum rossii Engler (Saxifragaceae) has been used as a nutritious food in Korea, but only minimal studies on this plant have been undertaken. We have examined the estrogenic effect of A. rossii and have discovered its potent constituents. To identify the estrogenic activity of A. rossii, we measured the transactivation of the estrogen-responsive element (ERE) in MCF-7 cells transfected with an ERE-containing construct after treatment of the extract and fractions of A. rossii. A. rossii showed a potent estrogenic activity and gallic acid ethyl ester; quercetin and kaempferol were identified as major constituents of the active fractions by liquid chromatography-nuclear magnetic resonance spectroscopy/mass spectrometry. We confirmed quercetin and kaempferol are the major active constituents after activity-guided isolation of seven compounds: gallic acid ethyl ester (1), quercetin (2), kaempferol (3), quercetin-3- O-(6″-galloyl)-β- d-glucopyranoside (4), quercetin-3- O-β- d-glucopyranoside (5), kaempferol-3- O-(6″-galloyl)-β- d-glucopyranoside (6), and kaempferol-3- O-β- d-glucopyranoside (7). These results show A. rossii could be a possible candidate for the treatment of postmenopausal symptoms. [ABSTRACT FROM AUTHOR]

The emergence of resistance against most of the drugs in current use against malaria has aggravated the disease burden in endemic regions. Several plants species have been used for treatment of malaria in traditional/cultural health systems. Bergenia ciliata, used traditionally for treatment of fever by local communities in the Himalayan Region, was evaluated for its plausible role as an antimalarial. Phytochemical screening of the ethanolic leaf extract of B. ciliata (ELEBC) revealed the presence of phenols, flavonoids, steroids and diterpenes. The extract showed good in vitro antiplasmodial activity, with an IC50 <10 μg/ml. Acute toxicity of the extract was observed to be >5 g/kg, which is considered toxicologically safe for oral administration. When tested in vivo, different concentrations of the extract (250 to 1,000 mg/kg) exhibited considerable chemosuppression on day 7, in a dose-dependent manner. Maximum chemosuppression was observed to be 87.50 % at 1,000 mg/kg. Administration of ELEBC (750 and 1,000 mg/kg) significantly ( p < 0.0005) enhanced the mean survival time of mice in comparison to infected control, which exhibited a mean survival time of 8.6 ± 1.5 days. Study reports presence of considerable in vitro and in vivo antimalarial activity in ethanolic leaf extract of B. ciliata for first time. Hence, the ethnopharmacological usage of the plant for treating fever is confirmed with experimental evidence. [ABSTRACT FROM AUTHOR]

Phyllonoma, a small tree genus of four species distributed from Mexico to Peru, has been placed in various families (mainly in Saxifragaceae), but now, based on molecular evidence, is placed in a distinct family Phyllonomaceae in Aquifoliales. To better understand the morphological relationships of the genus and family, I studied its floral morphology, anatomy, and vasculature using P. tenuidens. Most of the external and internal floral characteristics were described more than 120 years ago. Although some of them were confirmed, some were substantially revised, mainly those concerning the gynoecial structure. Flowers are small and basically pentamerous, consisting of five sepals, five petals, five stamens, and a gynoecium composed of two carpels usually in transversal position. Comparisons with other Aquifoliales show that Phyllonomaceae share the inferior ovary, epiphyllous inflorescence and epigynous disc nectary with East-Asian Helwingiaceae ( Helwingia only), but clearly differ from Helwingiaceae in having glandular trichomes on the sepal margins and a bicarpellate, unilocular gynoecium bearing many ovules on the parietal placentae. Evidence from floral morphology and structure supports the distinctness of Phyllonomaceae and its sister-group relationship with Helwingiaceae. Its floral characteristics suggest that Phyllonomaceae have evolved by adapting to distinct biological habitats in relation to pollination and seed dispersal. [ABSTRACT FROM AUTHOR]

Recent phylogenetic studies have shown that Saxifraga, as currently understood, must be divided into two genera: Saxifraga L. sensu stricto and Micranthes Haw. To better understand the evolutionary history of these two genera, we performed phylogenetic analyses inferred from the nuclear ribosomal sequences from the internal transcribed spacer and the sequences of the plastid DNA ( rbcL). Our molecular data confirmed the monophyly of the genus Micranthes and the consistency of the existing systematic treatments based on morphological criteria. Moreover, Micranthes species native from the Iberian Peninsula (i.e. M. clusii, M. lepismigena and M. stellaris) should be included into Micranthes sect. Arabisa. [ABSTRACT FROM AUTHOR]

Hydrangea s. l., belonging to the up-market segment of ornamental cultivars, currently faces a renaissance in horticulture. Hence, novel molecular-assisted breeding approaches are timely. Wide hybridization, i.e. crosses between distantly related species, has been shown to be problematic. Recent studies have considerably improved our knowledge of the phylogenetic relationships between the ornamental Hydrangea s. l. species. A fully resolved and highly supported phylogenetic tree is currently available, based on an extensive marker selection including 13 highly variable chloroplast markers. This robust phylogenetic framework includes the majority of widely cultivated Hydrangea s. l. species that have been the center of attention in a number of crossing projects. The present study is based on this highly supported phylogenetic hypothesis. Here, we aim to select the best candidates for future successful breeding projects, involving interspecific crosses of both closely and distantly related Hydrangea s. l. lineages. Therefore, we integrated the phylogenetic relatedness of potential parental lines along with genetic distances calculated from a wide plastid marker selection. Direct crosses between two species were found to be successful up to an average genetic distance of 0.01065, while failure could be expected at an average genetic distance of 0.01385 and higher. In order to overcome this genetic distance threshold, we propose Hydrangea arborescens, H. sargentiana, H. integrifolia, and H. seemannii as the best candidates for future bridge-cross projects with currently available fertile hybrids. We expect that our results will allow breeders to overcome long-standing wide crossing difficulties and motivate breeding initiatives of potential economic value. [ABSTRACT FROM AUTHOR]

Arctic plant species are expected to lose range due to climate change. One approach to preserve the genetic and species diversity for the future is to store propagules in seed vaults. However, germinability of seeds is assumed to be low for Arctic species. We evaluated ex situ storage potential of 113 of the 161 native angiosperms of Svalbard by studying seed ripening and germination. Seeds or bulbils were collected, and germinability was tested after one winter of storage in the Svalbard Global Seed Vault. Twenty-six of the species did not produce ripe propagules, 8 produced bulbils, and 79 produced seeds. Bulbils sprouted to high percentages. Seeds of 10 species did not germinate, 22 had low germination (<20 %), 34 had germination of 21-70 %, and 13 had high germination percentages (>70 %). More than 70 % of the species belonging to Asteraceae, Brassicaceae, Caryophyllaceae, Juncaceae, Rosaceae, and Saxifragaceae germinated. Cold tolerant, common species had higher germination percentages than relatively thermophilous, rare species. Germination percentages were six times higher than observed in 1969 ( n = 51) and 0.7 times that observed in 2008 ( n = 22), indicating that recent climate warming improves germination in the Arctic. While in situ conservation is of vital importance, ex situ conservation in seed banks is a potential complementary conservation strategy for the majority of Arctic vascular plant species. For species that did not germinate, other methods for ex situ conservation should be sought, for example, growing in botanical gardens. [ABSTRACT FROM AUTHOR]

To gain a better understanding of the anticomplement activity of triterpenoids, the complement activity of five unusual oleanane-type triterpenoids, bearing a carboxyl group at the C-29 position, were estimated against the classical pathway of a complementary system. The five triterpenoids were obtained from the roots of Aceriphyllum rossii (Saxifragaceae), and were determined to be aceriphyllic acids B-E ( 1-4) and K ( 5). Of the isolated compounds, compounds 1, 2 and 5 showed anticomplement activities, with IC values of 328.4, 77.5 and 348.6 μM, respectively, whereas, compounds 3 and 4 were inactive. This showed that a carboxyl group at the C-23 position and an α-configuration of a hydroxyl group at the C-3 position in the olean-29-carboxylic acid triterpenoids seemed to play an important role in the anticomplement activity of human serum against erythrocytes. [ABSTRACT FROM AUTHOR]

Embelia ribes, an important vulnerable medicinal liana, was regenerated through organogenesis and embryogenesis using leaf explants. Leaf explants produced organogenic calluses on MS medium supplemented with 1.0 mg l 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 mg l 6-benzylaminopurine. Shoot regeneration was obtained from organogenic calluses on MS medium containing different concentrations of thidiazuron (TDZ) and indole-3-acetic acid (IAA). The frequency of shoot bud organogenesis was highest (23.9 shoots/explant) in MS medium containing 0.5 mg l TDZ and 0.1 mg l IAA. The best result for induction of embryogenic callus was noticed in the combination of 2.0 mg l TDZ and 0.5 mg l 2,4-D. This callus, maintained in the same medium, showed the highest differentiation of embryos (56.5%) after 6 wk of culture. Embryos were transferred to MS medium supplemented with different concentrations of TDZ, and this facilitated conversion of embryos into plants. After 6 wk of subculture, MS medium with 0.05 mg l TDZ favored the highest percentage (52.2%) embryo conversion. As per the present protocol, 52.2% of the embryos underwent conversion, and a mean number of 29.5 shoots per culture was obtained. Shoots developed from both types of calluses were rooted on half-strength MS basal medium supplemented with 1.0 mg l indole-3-butyric acid. HPLC-UV assay demonstrated the highest embelin content (5.33% w/ w) in the embryogenic callus cultures. Embelin was isolated from embryogenic callus and was identified using IR and H NMR studies. [ABSTRACT FROM AUTHOR]

Pollen cell number was studied in 124 species of Saxifraga and six species of Micranthes. Binucleate pollen is present in all the six species of Micranthes studied and in 96 species of Saxifraga. Trinucleate pollen occurs in 28 species of Saxifraga and is confined to section Ciliatae subsection Hirculoideae, where it is a putative synapomorphy, and to two species of subsection Serpyllifoliae. Trinucleate pollen does not characterise the whole of section Ciliatae as has been thought. The state has probably evolved at least twice, and possibly three times, in the genus. One new nomenclatural combination is made in Micranthes. [ABSTRACT FROM AUTHOR]

Climate change will cause large-scale plant migration. Seedling recruitment constitutes a bottleneck in the migration process but is itself climate-dependent. We tested the effect of warming on early establishment of three Arctic pioneer species, while holding other environmental variables constant. Seeds and bulbils were sown in artificial gaps in dry Arctic tundra and subjected to a 13-day heating of the soil surface by 2–8°C, simulating temperature increases ranging from the general summer warming to heat waves projected to occur more frequently with global warming. All species showed decreased establishment with increasing soil surface temperature. The short-term heat pulse decreased establishment of Polygonum viviparum and Saxifraga cernua, whereas establishment of Cerastium alpinum decreased with temperature due to more permanent natural variation in micro-climate. The treatment effects increased by the quadrat of the temperature increase. Warming and in particular heat waves may result in declining establishment of Arctic plants in dry tundra regions. [ABSTRACT FROM AUTHOR]

This paper illustrates the phylogeographical structure of Saxifraga callosa in order to describe its genetic richness in refugial areas and to reconstruct its glacial history. S. callosa is a species spread throughout south-east France and Italy with a high distribution in the Maritime Alps. Four chloroplast microsatellite and AFLP markers were analyzed in populations of S. callosa. The size variants of all tested loci amount to 11 different haplotypes. Intrapopulational haplotype variation was found in two of the populations analyzed: on the Mt. Toraggio in the Maritime Alps, and in the Apuan Alps. On the other hand, no intrapopulational variation was found in 25 populations, most of which were sampled from isolated areas. Analysis of the haplotype distribution showed that population subdivision across all populations was high ( GST = 0.899). Moreover, its genetic structure was studied using AMOVA and STRUCTURE analysis. The study legitimated inferred conclusions about the phylogeographical structure of the species and identified centers of diversity. Considerations concerning genetic structure and divergence among three major clades (Maritime Alps, Apuan Alps and Apennines), the patchy distribution of haplotypes, and the high number of private haplotypes support the proposal that S. callosa survived in some refugia within the Italian Peninsula refugium, and that mainly northern populations of refugia were involved in postglacial recolonization. [ABSTRACT FROM AUTHOR]

Narrowly-ranging species frequently harbor less genetic variability relative to widespread relatives and face graver extinction threats due to the heightened impacts of stochastic events on ecological and genetic diversity. In this study, we examined the impact of historical and current threats to the maintenance of genetic variation in Lithophragma maximum (Saxifragaceae), a perennial herb endemic to San Clemente Island, California. This species exists as small populations confined to canyons along 4 km of the southeast coastline of the island. In 15 populations analyzed with 10 microsatellite markers, we identified an average of 2.05 alleles per locus and 58.7% polymorphic loci. Significant departures from Hardy-Weinberg equilibrium existed in six populations; five of these exhibited heterozygote deficiency. Bayesian inference of genetic structure indicated a significant amount of structure among populations and canyons and infrequent gene flow even over very short distances. We also identified a significant and positive correlation between genetic and geographic distances, indicative of isolation by distance. There was no evidence of recent bottlenecks in any of the sampled populations, but older bottlenecks were detected in two populations. These results suggest that populations of L. maximum have historically been small and isolated, which is likely due to the rugged habitat in which this species occurs and limited pollen and seed dispersal. Given the high degree of structure observed across populations, we suggest that conservation efforts should focus on preserving populations in multiple canyons, maintaining large population sizes to preserve genetic variation, and controlling the spread of invasive species in areas where L. maximum occurs. [ABSTRACT FROM AUTHOR]

Seven flavonoids ( 1–7), two triterpenoids ( 8 and 9) and four steroids ( 10, 11, 12 and 13) were isolated from the whole plant of Tiarella polyphylla. Based on the physicochemical and spectroscopic analyses, their structures were identified as myricetin ( 1), astragalin ( 2), afzelin ( 3), quercitrin ( 4), myricitin ( 5), nicotiflorin ( 6), isoquercitrin ( 7), tiarellic acid ( 8), 3β-hydroxy-20(29)lupen-27-oic acid ( 9), β-sitosterol-3- O-β-D-glucoside ( 10), stigmasterol-3- O-β-D-glucoside ( 11), β-sitosterol ( 12) and ergosterol endoperoxide ( 13). All 13 compounds, with the exception of tiarellic acid were isolated for the first time from T. polyphylla. In the anti-complementary assay, the steroids ( 12 and 13) exhibited potent activities; whereas, the flavonoids ( 1 to 7) showed weak or no activities, but even the triterpenoids ( 8 and 9) and steroidal saponins ( 10 and 11) evoked hemolysis. [ABSTRACT FROM AUTHOR]

Tolmiea diplomenziesii, the diploid entity traditionally treated within a broadly circumscribed Tolmiea menziesii, is here formally described. Evidence is provided that this new species represents the diploid sister lineage to T., menziesii, which is re-circumscribed to include only autotetraploid plants. The diploid and autotetraploid entities are compared, and serve as an example of the level of taxonomic evidence for specific status that we consider appropriate for recognition of a cytological entity as a distinct species. [ABSTRACT FROM AUTHOR]

In contrast to many declining plant species Saxifraga tridactylites extended its distribution range in the man- made landscape of central Europe. The species naturally colonizes rocks and calcareous grasslands, but has also spread enormously in anthropogenic habitats such as railway constructions during the last decades. To analyze the genetic structure of the species 216 individuals from 8 populations in natural and 5 populations in man-made habitats were studied using AFLPs. The molecular analysis resulted in 250 scorable fragments. Population variability, measured as Nei's gene diversity, Shannon's Information Index and percentage of polymorphic bands, was slightly but not significantly higher in populations from natural habitats and was not correlated with population size. Mantel test indicated no significant correlation between pairwise genetic (ɸPT) and geographic distances. An analysis of molecular variance revealed significant differentiation between the two habitat types. About 9% variability were observed between natural and man-made habitats, 21% among populations within these two habitats and 70% within populations. In a neighbour joining cluster analysis populations from natural and man-made habitats were clearly separated from each other. Populations of S. tridactylites from man-made habitats do, therefore, not suffer from reduced genetic diversity. The observed genetic differentiation between populations from man-made and natural habitats could be due to reduced gene flow and/or habitat specific selection. However, the results of the study clearly demonstrate human impact on the genetic structure of plant populations in man-made landscapes. [ABSTRACT FROM AUTHOR]

The genetic structure of populations of an arctic-montane herb, Saxifraga hirculus (Saxifragaceae), was analysed by means of chloroplast restriction fragment-length polymorphism. Sampled populations were distributed across Europe and North America (Alaska and Colorado). There was no evidence for geographically structured genetically divergent lineages, and although no haplotypes were shared between North America and Europe, the haplotypes from different continents were intermixed on a minimum spanning tree. European populations were much more highly differentiated and had much lower levels of haplotype diversity than their Alaskan counterparts. Centres of haplotype diversity were concentrated in those Alaskan populations located outside the limits of the last (Wisconsin) glaciation, suggesting that they may have acted as refugia during the Pleistocene. It was not possible to identify putative migration routes or corresponding refugia in the European genepool. One British population, from the Pentland Hills, was genetically very distant from all the others, for reasons that are as yet unknown.Heredity (2006) 96, 222–231. doi:10.1038/sj.hdy.6800785; published online 8 February 2006 [ABSTRACT FROM AUTHOR]

Cladistic and phenetic analyses of leaf and other morphological characters of Gunnera strongly support monophyly of the genus, with the Saxifragaceae s.str. as the closest sister group. This morphologically based phylogeny provides a more coherent understanding of the evolutionary history of Gunnera than do recent phylogenetic hypotheses based on genetic data sets with Myrothamnaceae as the sister group. Simple, crenate, palinactinodromously veined leaves lacking freely ending veinlets and tricolpate, tectate-perforate pollen with a reticulate exine indicate a shared ancestry. Within the genus Gunnera all six traditionally recognized subgenera are monophyletic, as supported by leaf architectural apomorphies. The monotypic subgenus Ostenigunnera is the sister group to the other five subgenera, which can be divided into two principal lineages. One lineage includes the subgenera Milligania and Misandra, characterized by a prostate stoloniferous habit with small, low-rank leaves and exclusively unisexual flowers, whereas the other lineage includes the subgenera Perpensum, Pseudo-Gunnera, and Panke, all of which possess at least some hermaphroditic flowers and larger, high-rank leaves. When the phylogeny of the subgenera is considered in light of biogeography and the fossil record, a number of cladogenetic events can be explained by continental vicariance in the Late Cretaceous. The African Perpensum became distinct from the other large-leafed lineage with the separation of the African continent ca. 90 Ma. The two small-leafed lineages, the subgenera Milligania and Misandra, split with the separation of New Zealand from Western Gondwana, about 80 Ma. Pseudo-Gunnera became isolated from Panke prior to this time, when Panke fossils occur in North America. Gunnera probably arose out of an early herbaceous radiation of tricolpate eudicots having close affinity to the basal Saxifragaceae, especially the genus Chrysosplenium. [ABSTRACT FROM AUTHOR]

The methanol extract obtained from the aerial parts of Aceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc), n-BuOH and H2O layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc and n-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3- O-β-D-glucopyranoside (astragalin, 1), quercetin 3- O-β-D-glucopyranoside (isoquercitrin, 2), kaempferol 3- O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside ( 3), quercetin 3- O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyrano-side (rutin, 4), kaempferol 3- O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] ( 5) and quercetin 3- O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] ( 6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound 1 exhibited the highest antioxidant activity in the ABTS 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging method. 100 mg/L of compound 1 was equivalent to 72.1±1.4 mg/L of vitamin C, and those of compounds 3 and 5 were equivalent to 62.7±0.5 mg/L and 54.3±1.3 mg/L of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound 5 exhibited the highest activity with an IC50 value of 17.6 ± 0.3 μM. In addition, some physical and spectral data of the flavonoids were confirmed. [ABSTRACT FROM AUTHOR]

Observations of insects visiting strongly protandrous flowers of Tolmiea menziesii (Saxifragaceae) show that Gnoriste megarrhina (Mycetophilidae), a large fungus gnat with a body ca. 7 mm long and a proboscis ca. 6.5 mm long, is the primary pollinator. Pollen is transferred to ventral portions of the gnat’s thorax while it probes for an unusually dilute nectar (8.3% to 12% sucrose equivalents) produced at the base of the floral tube. Grains are transferred to the two receptive stigmas on each pistil when it forages for nectar on a female phase flower. Pollen load analyses indicate that Tolmiea menziesii may be the only nectar source visited by the gnat while it is in bloom. While hoverflies (Syrphus spp.) and bumblebees (Bombus spp.) also visit T. menziesii flowers, they do not forage for nectar and usually behave as pollen robbers visiting only male phase flowers after earlier visits by G. megarrhina. When the modes of floral presentation of T. menziesii are compared to other species pollinated primarily by micro-dipterans, and mycetophilids in particular, there appears to be a floral convergence in some spring-flowering, perennial herbs of moist, evergreen woodlands and forests. Analyses of open (gnat-pollinated) vs. hand-pollinated pistils show that manual cross-pollinations are slightly more successful than open pollinations. Fluorescence microscopy confirms two sites of self-recognition and rejection within the pistil: following controlled self-pollination experiments almost half of the pollen tubes produced either stop growing once they reach the top of the ovary and/or grow horizontally. The remaining tubes produced by self-pollination penetrate ovules but seed is never set. This double mode of self-recognition and rejection is similar to the one described for Heuchera micrantha var. diversifolia (Saxifragaceae) but may also confirm an earlier report of post-zygotic rejection made for Tolmiea. [ABSTRACT FROM AUTHOR]

In the forest understorey, shrubs usually reproduce vegetatively rather than sexually, but the relative contribution of these two reproductive modes may vary with temporal changes in environmental conditions (e.g., light, substrates of forest floor) that are closely related to forest dynamics. To evaluate the occasional changes in reproductive modes of the clonal understorey shrub Hydrangea paniculata, the reproductive characteristics (i.e., flowering, seedling establishment, vegetative propagation, reproductive size and age) were investigated in four different developmental stages in a Japanese beech forest (early gap, EG; late gap, LG; building, BU; mature, MA). Flowering individuals occurred only in EG and LG, and a much greater number of seedlings was observed in both EG and LG than in BU and MA, mainly because canopy gaps provided sufficient light for flowering and suitable substrates (fallen trees and exposed mineral-soil) for seedling establishment. The flowering individuals originated from plants that had persisted in the shaded understorey until gap formation. In contrast to sexual reproduction, clonal fragmentation increased with forest development in the order LG, EG, BU, MA. This is because, in later stages of forest dynamics (BU and MA), large individuals, some of which had previously flowered in gap stages, were layered on the forest floor and subsequently produced a substantial number of clonal fragments by separation of the buried branches from the main stems which had decayed. This resulted in a large number of clonal fragments originating from a single mother plant. These results suggest that the reproductive modes of H. paniculata is strongly influenced by the changes in environmental conditions with respect to the dynamics of canopy trees. Reproduction from seed in gap stages, despite their short period, provide new genets in established populations, whereas vegetative propagation via fragmentation in closed-canopy stages enhance the stability of the population until the next disturbance. [ABSTRACT FROM AUTHOR]

Reports that little research has been conducted in the Himalayan and Karakorum Highlands of northern Pakistan on the aspects of biodiversity and conservation. Research that was carried out within the scope of the Pakistan?German Research Project, `Culture Area Karakorum? which aims to highlight the `Problems and Prospects of High-Mountain Research? in northern Pakistan; Description of the floral biodiversity of this area in northern Pakistan; Discussion of the areas exploitation by entities with certain management implications to follow; Collection of species, their preservation and dialogue with the local, rural communities that offered information on the plant biodiversity; Dominance that has been observed for Asteraceae, Polygonaceae, Saxifragaceae and Rosaceae; Plant species from Naltar that emerged as ethnobotanically important for local medicinal uses and some commercial uses; Thymus serpyllum, Gentiana tianshanica, Stellaria graminea, Geranium wallichianum and Capparris spinosa that are the most important medicinal plants and their demand that has increased; Cedrus deodara that has completely disappeared from Naltar and Willow Salix sp. that has almost been eradicated, except in the sub-alpine belts; Diversity of plant species within this remote area; Species that are new additions to the plant list in this area; Use of some species by the indigenous communities; Extensive grazing, uprooting of plants and soil-slope erosion that intensify the environmental problems; Species that are used for curing diseases; Area that has been given low priority; Hospitable populations that have a greater potential for the success of conservation and the wise usage of programs; Efforts that are required to broaden our understanding of the dynamics of floral values as well as local concepts in this remote part of the world, and to check species decline; Controlled harvesting and aforestation that may be the solution; Field conservation/management research that is needed.

A new 27-carboxylic lupane-type triterpene, tiarellic acid ( 1), was isolated from Tiarella polyphylla together with corosolic acid ( 2) and tormentic acid ( 3). Tiarellic acid was characterized as 3,23-dihydroxy-20(29)-lupen-27-oic acid and its NMR data were unambiguously assigned using 2-D NMR techniques. [ABSTRACT FROM AUTHOR]

Polyploidization has played an essential role in the diversification of seed plants and often has profound effects on plant physiology and morphology. Yet, little is known about how plant polyploidization has shaped the ecology and evolution of interactions between phytophagous insects and their hosts. Polyploidization could either facilitate or impede colonization of new hosts. Greya politella (Lepidoptera: Prodoxidae) is highly specialized on plants in the genus Lithophragma (Saxifragaceae) throughout most of its geographic range. In central Idaho, some populations have shifted to the related Heuchera grossulariifolia, a plant that has repeatedly undergone autopolyploidization. Previous studies have shown that populations feeding natively on H. grossulariifolia prefer tetraploids to diploids in naturally mixed stands. We investigated whether this difference is caused by an inherent preference for tetraploids, or if the preference in present Heuchera-feeding populations has evolved over time. Moths from a strictly Lithophragma-feeding population were tested for preference of diploid or tetraploid H. grossulariifolia, using a combination of field experiments and caged choice trials. In all trials, attack rates on these non-hosts were very low, with no significant difference between ploidies. In addition, there was little evidence that females manipulated their clutch sizes when ovipositing into different plant species or ploidy levels. Hence, the local shift from Lithophragma to Heuchera in central Idaho is not due to failure of the moths to discriminate between these plant species. Furthermore, the higher attack rates on tetraploids in native H. grossulariifolia-feeding populations cannot be caused by a higher initial preference for these plants, but must instead be a result of differences in plant phenology and/or selection acting on local populations. [ABSTRACT FROM AUTHOR]

An antifungal acetophenone glycoside has been isolated from the methanol extract of the roots of Ribes rubrum (Saxifragaceae). The structure was established by spectrometric (UV, mass spectrometry, and1H and13C NMR) and chemical methods. Extracts of four different tissues of R. rubrum, the fruits, leaves, stem bark, and roots, have been compared by use of HPLC combined with UV detection and electrospray-ionization mass spectrometry (ES-MS). [ABSTRACT FROM AUTHOR]

Parsimony analyses of 54 nrDNA ITS (Internal Transcribed Spacer) sequences of Saxifraga sect. Saxifraga were performed. In addition to some unresolved clades, there is strong disagreement between the ITS phylogeny and previous classifications based primarily on morphology. The extensive cytological instability of sect. Saxifraga prevents previous cytotaxonomical results from resolving the incongruence between molecular and morphological data. Dissimilar topologies between chloroplast ( matK) and nuclear (ITS) trees for eight species of sect. Saxifraga suggest that gene trees and the true species tree are not coincident. Recent and mid-term reticulation is proposed as an explanation for the incongruence between morphological, cytological, organellar, and nuclear data. Homogenization in multigene families, such as the ITS region, via concerted evolution may be the key to the interpretation of results based on ITS sequences within sect. Saxifraga. The use of organellar genes in a larger sample should help to determine whether extensive reticulation occurs in sect. Saxifraga, as has been documented in various genera of Saxifragaceae. [ABSTRACT FROM AUTHOR]

Seven known oleanolic acid glycosides ( 1–7) were isolated from the MeOH extract of Tiarella polyphylla. The structures were identified to be 3- O-(β-D-glucopyranosyl) oleanolic acid ( 1), 3- O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] oleanolic acid ( 2), 3- O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] oleanolic acid ( 3), 3- O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] oleanolic acid 28- O-β-D-glucopyranosyl ester ( 4), 3- O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] lleanolic acid 28- O-β-D-glucopyranosyl ester ( 5), 3- O-[a-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] oleanolic acid ( 6), and 3- O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] oleanolic acid 28- O-β-D-glucopyranosyl ester ( 7) on the basis of physicochemical and spectral data. These triterpene glycosides were tested for the anticomplement activity and hemolytic activity. Bisdesmosidic saponins, 4, 5, and 7, showed anticomplement activity; in contrast, monodesmosidic saponins, 1–3, and 6, showed direct hemolytic activity. Methyl esterified monodesmosidic saponins showed anticomplement activity at a low concentration and hemolytic activity at a high concentration. [ABSTRACT FROM AUTHOR]

The roles of hybridization and of introgression as potential threats to small native populations are current topics of interest both for evolutionary and conservation biologists. Two factors are mainly involved in the threat to natural populations through hybridization: demographic swamping and genetic assimilation. At prealpine locations, two Saxifraga species with very different growth habits, S. aizoides and S. mutata, form a hybrid, S. × hausmannii. Investigation of meiosis and crossing experiments revealed regular pairing of the 26 chromosomes and development of viable seeds in the hybrid. Analysis of hybrid indices, GPI allozymes, germination experiments and seed sizes showed an intermediate position of S. × hausmannii between its parental species. Saxifraga aizoides and S. mutata were separated by only weak hybridization barriers. Introgression occurred mostly in direction of S. aizoides, although to a small amount. There is no actual threat to small, prealpine populations of S. aizoides and S. mutata through interspecific gene flow because hybridization is localized, resulting from different flowering phenologies of the parental species and from the narrow habitat requirements of S. × hausmannii, which are similar to those of S. aizoides. The major threat to local, prealpine populations of S. aizoides and S. mutata is the loss of landscape dynamics. Both species need open erosion slopes for successful recruitment. [ABSTRACT FROM AUTHOR]

The phylogeny of Japanese species of Chrysosplenium (Saxifragaceae) was examined using variation in DNA sequences. Sequences of rbcL and matK genes were compared for their feasibility for reconstructing the phylogeny of Chrysosplenium, and the matK sequences was found to give greater resolution. All but one of the 17 Japanese species have been examined for matK gene sequences and phylogenetic analysis of these data resulted in eight most parsimonious trees of 390 steps and a consistency index (Cl) of 0.823. The molecular phylogeny obtained was generally in agreement with Hara's (1957) classification based upon phenotypic similarity, although a conclusion needs extensive examination of the genus on a world-wide level. Using the phylogenetic data, character evolution was examined, especially in the characters traditionally used for grouping infrageneric taxa. Differentiation of opposite and alternate phyllotaxis appears to have occurred only once in the course of evolution of Chrysosplenium. [ABSTRACT FROM AUTHOR]

Saxifraga oppositifolia, S. biflora, and their hybrid S. × kochii were studied in a mixed population in the Swiss Alps. Qualitative morphological characters did not allow to clearly separate the hybrid S. × kochii from its parental species. All quantitative characters were intermediate in S. × kochii, but the ranges of these characters overlapped with those of S. oppositifolia and S. biflora. A hybrid index and canonical discriminant analysis allowed a clear separation of the three groups and strongly confirmed a priori grouping. Phenological observations showed that the three groups were not temporally separated within the investigated mixed population. Reciprocal hand pollinations between S. oppositifolia and S. biflora yielded higher seed set with S. oppositifolia than with S. biflora as maternal plant. Germination rate of seeds from these crossing experiments varied in the same way as seed yields, whereas germination rate was intermediate for seeds from naturally pollinated S. × kochii. Considering its ecological and reproductive properties, S. × kochii has good prerequisites for evolving into a distinct species. [ABSTRACT FROM AUTHOR]

Chromosome numbers, mainly gametic, are given for 28 populations belonging to 13 species in ser. Ceratophyllae as circumscribed by Webb & Gornall. From a cytological point of view, we report or confirm the occurrence of aneuploidy in at least 8 of the 19 species recognized. This phenomenon, together with the technical difficulties inherent to the genus, is responsible for a number of incorrect or imprecise previous reports which are here questioned. Aneuploidy and the karyological instability behind it apparently reflect very active extant processes which might play an important role in the evolution of the group. Cytological and morphological data allow the recognition of four groups; one of them is likely to constitute a monophylectic group (ser. Ceratophyllae sensu stricto) but, the monophyly of the series Ceratophyllae sensu lato is questioned. [ABSTRACT FROM AUTHOR]

Tiarella trifoliata comprises varieties laciniata, trifoliata, and unifoliata, and is distributed from southeastern Alaska to northern California. We analyzed restriction site variation of chloroplast DNA (cpDNA) using 23 endonucleases in 76 populations representing the entire geographic range of the species and the three recognized varieties. We also employed comparative restriction site mapping of PCR-amplified chloroplast DNA fragments using 16 restriction endonucleases. This species exhibits low cpDNA restriction site variation. No differentiation is evident among varieties of this species based on cpDNA data; some plants of each variety were characterized by each of the two major cpDNA types detected. The two major cpDNA clades, which differ by only a single restriction site mutation, are geographically structured. A northern clade comprises populations from Alaska to central Oregon; most populations analyzed from southern Oregon and California form a southern clade. Populations that possess the typical northern cpDNA type also occur disjunctly to the south at high elevations in the Siskiyou-Klamath Mountain area of southern Oregon and northern California. Conversely, the southern cpDNA type is found disjunctly to the north in the Olympic Peninsula of Washington. Both geographic areas characterized by disjunct cytoplasms are considered glacial refugia. Tiarella trifoliata joins two other species, Tolmiea menziesii and Tellima grandiflora, in having well-demarcated northern and southern cpDNA lineages. All three species have similar life-history traits and geographic distributions. We suggest that glaciation may have played a major role in the formation of the cpDNA discontinuities present in these three taxa. The pronounced relationship between cpDNA variation and geographic distribution suggests the potential applicability of 'intraspecific phylogeography' to plants via the analysis of intraspecific cpDNA variation. These three examples also join a rapidly growing data base which indicates that cytoplasms are often geographically structured within species and species complexes. [ABSTRACT FROM AUTHOR]

The occurrence of gynodioecy in two populations in northern England of the normally hermaphrodite Saxifraga granulata is reported. Female plants have aborted stamens, and smaller petals than hermaphrodites. At Staindrop, County Durham, an estimated 23% of the flowering stems were female; at Macclesfield, Cheshire, 4% were female. The inheritance of male sterility is not simple, and probably involves at least one cytoplasmic and two nuclear genes. The secondary sexual characteristics, hermaphrodite-predominant sex ratios, and complex inheritance of male sterility, are typical of gynodioecious populations. [ABSTRACT FROM AUTHOR]

Scanning electron microscopical investigations of flower buds of the perennial herb Bergenia cordifolia ( Haw.) A. Br. ( Saxifragaceae) reveal a primitive gynoecium. During ontogenesis the margins of the carpel lamina transgress on the apical cone of the axis by meristem incorporation and finally fuse with the margins of the opposite carpel. These processes of meristem incorporation and fusion first lead to gamophylly and furthermore to carpel peltation, as is demonstrated by SEM-photographs (ring-shaped dike and common septum of the two carpels). As a result of carpel peltation, the lowest point of the septum deliminates the synascidiate zone. Above this point, the symplicate and, eventually, the plicate zone follows (vid. ventral suture). The margins of the carpel lamina merely touch each other without being coalesced. The preparation of a window in the carpel's dorsal side permits a look at a massive lateral placenta ( Leinfellner 1951) developing the ovules. In the lower third-in lateral position at the placenta's margin-the first ovules are seen, the next ones follow in acropetal and basipetal direction, as well as to the periphery of the placenta. [ABSTRACT FROM AUTHOR]

Seven secoiridoid glycosides, secologanin dimethyl acetal ( 1), n-butyl vogeloside ( 2), n-butyl epi-vogeloside ( 3), (7 R)- n-butyl morroniside ( 4), hydrangenoside A ( 5), hydrangenoside C ( 6), and hydrangenoside A dimethyl acetal ( 7), have been isolated from the leaves of Hydrangea macrophylla subsp. serrata (T hunb.) M akino (Saxifragaceae). The structures were elucidated on the basis of spectral data. [ABSTRACT FROM AUTHOR]