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Chromosome numbers, ploidy level, distribution, localities, and selected prior chromosome counts are detailed for eight taxa belonging to the Asteraceae family including the first count in Hieracium hastile. All of these species grow in the Pyrenees. [ABSTRACT FROM AUTHOR]

Premise of the Study: Although an evolutionary link between breeding system and dispersibility has been proposed, to date empirical data and theoretical models of plants show contrasting trends. Methods: We tested two competing hypotheses for the association between breeding systems and dispersibility in the heterocarpic Hypochaeris salzmanniana (Asteraceae) by using both an experimental approach and surveys over 2 years of five natural populations along an environmental cline with a gradient of pollinator availability. Key Results: Hypochaeris salzmanniana produced two types of fruits, beaked (BF) and nonbeaked (NBF), which differ in their dispersal ability. The BF were lighter and had a lower dropping velocity and higher dispersal distance than the NBF. Potential for long‐distance dispersal, measured as BF ratio per head, had high narrow‐sense heritability. Greater dispersibility and selfing ability were linked at all the scales studied. Both selfed BF and NBF fruits had longer plumes and lower plume loading than outcrossed fruits, characteristics that promote farther dispersal. Natural populations with a higher percentage of self‐compatible plants showed a higher BF ratio. Moreover, selfing led to a higher BF ratio than outcrossing. Conclusions: The avoidance of inbreeding depression seems to be the most plausible selective pressure for the greater dispersibility traits of selfed seeds. Furthermore, the ability to modulate the BF ratio and thus the potential for long‐distance dispersal of offspring based on its selfed or outcrossed origin could be advantageous, and therefore selected, under unpredictable pollination environments that favor higher dispersive selfers, which overcome both pollen limitation and inbreeding avoidance. [ABSTRACT FROM AUTHOR]

Scientists have been interested in many topics driven by biological invasions, such as shifts in the area of distribution of plant species and rapid evolution. Invasiveness of exotic plant species depends on variations on morphological and reproductive traits potentially associated with reproductive fitness and dispersal ability, which are expected to undergo changes during the invasion process. Numerous Asteraceae are invasive and display dimorphic fruits, resulting in a bet-hedging dispersal strategy –wind-dispersed fruits versus animal-dispersed fruits–. We explored phenotypic differentiation in seed morphology and reproductive traits of exotic (Chilean) and native (Spanish) populations of Hypochaeris glabra. We collected flower heads from five Spanish and five Chilean populations along rainfall gradients in both countries. We planted seeds from the ten populations in a common garden trial within the exotic range to explore their performance depending on the country of origin (native or exotic) and the environmental conditions at population origin (precipitation and nutrient availability). We scored plant biomass, reproductive traits and fruit dimorphism patterns. We observed a combination of bet-hedging strategy together with phenotypic differentiation. Native populations relied more on bet-hedging while exotic populations always displayed greater proportion of wind-dispersed fruits than native ones. This pattern may reflect a strategy that might entail a more efficient long distance dispersal of H. glabra seeds in the exotic range, which in turn can enhance the invasiveness of this species. [ABSTRACT FROM AUTHOR]

Intensive rotational grazing systems (also called cell grazing, holistic grazing or time-controlled grazing) are often implemented to improve production and environmental outcomes. Over recent years there has been considerable interpretation and adaption of the holistic principles that guide the management of these systems. In southern Australia, this has led to an increasing use of longer rest periods for intensive rotational grazing. This experiment was established to compare three intensive rotational grazing strategies (fast rotation [FR], average 57-day rest; slow rotation [SR], average 114-day rest; and flexible grazing [FX], based on availability of green herbage mass) with continuous grazing (CG) to assess the impact these systems have on vegetation and diet quality. The grazing treatments were run across three production zones (PZs) in the landscape (low [LPZ], medium [MPZ] and high [HPZ]) to determine whether management by landscape interactions influenced vegetation. Pasture composition was mostly influenced by PZ in the landscape withMicrolaena stipoidesandHolcus lanatusmore prevalent in the HPZ andRytidospermaspp. more common in the LPZ. The intensive rotational grazing treatments all had greater herbage mass and ground cover than CG. Composition change often occurred in one PZ and not another (e.g.Hypochaeris radicataincreased with SR in the LPZ), or there were contrasting effects in different parts of the landscape (e.g.M. stipoidesincreased with FR compared with CG in the HPZ but decreased in the LPZ). Diet quality was lower for the SR compared with the other grazing treatments. Maintaining a post-grazing benchmark of >0.5 t green DM ha−1was associated with a higher diet quality. Based on this two-and-a-half-year study run during poor seasons, it can be concluded that intensive rotational grazing can be managed, with fast and flexible rotations, to achieve per head animal performance similar to CG, but with higher herbage mass, ground cover and a desirable pasture composition. [ABSTRACT FROM AUTHOR]

Small felids influence ecosystem dynamics through prey and plant population changes. Although most of these species are threatened, they are accorded one of the lowest research efforts of all felids, and we lack basic information about them. Many felids occur in sympatry, where intraguild competition is frequent. Therefore, assessing the role of interspecific interactions along with the relative importance of landscape characteristics is necessary to understand how these species co-occur in space. Here, we selected three morphologically similar and closely related species of small Neotropical cats to evaluate the roles of interspecific interactions, geomorphometry, environmental, and anthropogenic landscape characteristics on their habitat use. We collected data with camera trapping and scat sampling in a large protected Atlantic forest remnant (35,000 ha). Throughout occupancy modeling we investigated whether these species occur together more or less frequently than would be expected by chance, while dealing with imperfect detection and incorporating possible habitat preferences into the models. We used occupancy as a measure of their habitat use. Although intraguild competition can be an important determinant of carnivore assemblages, in our system, we did not find evidence that one species affects the habitat use of the other. Evidence suggested that proximity to the nature reserve (a more protected area) was a more important driver of Neotropical spotted cats’ occurrence than interspecific interactions or geomorphometry and environmental landscape characteristics—even though our entire study area is under some type of protection. This suggests that small felids can be sensitive to the area protection status, emphasizing the importance of maintaining and creating reserves and other areas with elevated protection for the proper management and conservation of the group. [ABSTRACT FROM AUTHOR]

The genus Hypochaeris has a recent evolutionary history caused by long-distance dispersal in conjunction with adaptive radiation in the South American continent. Hypochaeris lutea is a perennial herb that grows mostly at altitudes of around 1000 m in cold swamps of the southern regions of Brazil. We investigated the amplified fragment length polymorphism ( AFLP) in 270 individuals representing 11 Brazilian populations of H. lutea to elucidate the population genetic structure of this species. The frequencies of polymorphic loci and gene diversity ranged from 83.42% to 91.66% and from 0.26 to 0.34, respectively. Analysis of molecular variance revealed that most of the genetic variability was found within (76.67%) rather than among (23.3%) populations, agreeing with the pattern of genetic distribution within and among populations observed in other allogamous species of Hypochaeris. A Mantel test showed no correlation between genetic and geographic distances when all populations were considered. Simulations performed using a Bayesian approach consistently identified two clusters with different admixture proportions of individuals, as also revealed by a UPGMA dendrogram of populations. The pattern of genetic structure observed in H. lutea is consistent with a process of successive colonization events by long-distance dispersal resembling the rapid and recent radiation that has been proposed to explain the origin of the South American species of Hypochaeris. [ABSTRACT FROM AUTHOR]

The association of cytogenetic and molecular techniques has contributed to the analysis of chromosome organization and phylogeny in plants. The fluorochrome GC-specific CMA3, fluorescent in situ hybridization (FISH) and RAPD (Random Amplified Polymorphic DNA) markers were used to investigate chromosome structure and genetic relationships in Hypochaeris (Asteraceae). Seven species native to South America, and two species introduced from Europe (H. glabra and Hypochaeris sp) were studied. FISH with rDNA probes identified one or two loci of 18S-5.8S-25S rDNA in the South American Hypochaeris species and one locus in the European species. Only one 5S rDNA locus was seen in all species studied. Blocks of GC-rich heterochromatin (CMA-positive bands) associated to 18S-5.8S-25SrDNA loci were detected in all species investigated. Co-location of 5S rDNA and CMA bands was also observed, except for three South American species and Hypochaeris sp. In two South American species, additional CMA bands not related to rDNA were observed on the long arm of chromosome 2, near to the centromere. Hypochaeris glabra exhibited additional CMA-positive signals distributed at pericentromeric regions, on the short arms of all chromosomes. A total of 122 RAPD markers were used to determine the genetic relationships among species. The level of polymorphism was very high, revealing two genetic groups comprising the South American and the European species, thus supporting a previous hypothesis of monophyly of the South American Hypochaeris species. The coefficients of genetic similarity between European and South American species were 0.35, on average. Polymorphism was also high within the two groups. The genetic associations observed with RAPD markers were consistent with chromosome characteristics. Species carrying similar distribution of 45S rDNA loci and CMA-positive signals were included in the same group revealed by RAPDs. Cytogenetic and molecular data support the view that not only chromosome rearrangements, but also changes in DNA sequence took place during the diversification of the South American Hypochaeris species.

Hypochoeris radicata, an invasive plant species, is a large and growing threat to ecosystem integrity on Jeju Island, a UNESCO World Heritage site. Therefore, research into the utilization of H. radicata is important and urgently required in order to solve this invasive plant problem in Jeju Island. The broader aim of our research is to elucidate the biological activities of H. radicata, which would facilitate the conversion of this invasive species into high valueadded products. The present study was undertaken to identify the pharmacological effects of H. radicata flower on the production of inflammatory mediators in macrophages. The results indicate that the ethyl acetate fraction of H. radicata extract (HRF-EA) inhibited the production of pro-inflammatory molecules such as NO, iNOS, PGE2, and COX-2, and cytokines such as TNF-α, IL-1β, and IL-6 in LPS-stimulated RAW 264.7 cells. Furthermore, the phosphorylation of MAPKs such as p38, ERK, and JNK was suppressed by HRF-EA in a concentration- dependent manner. In addition, through HPLC and UPLC fingerprinting, luteolins were also identified and quantified as extract constituents. On the basis of these results, we suggest that H. radicata may be considered possible anti-inflammatory candidates for pharmaceutical and/or cosmetic applications. [ABSTRACT FROM AUTHOR]

Radiation into different environments is a common evolutionary phenomenon in plants. This process has been extensively documented in oceanic islands and to a lesser extent in continental areas. The genus Hypochaeris (Asteraceae: Cichorieae) contains 41 species in South America that have evolved during the past one million years. Dispersal of propagules to new regions followed by speciation at the diploid level into different ecological zones has resulted in radiated groups. One such group, the H. apargioides complex, consists of four closely related species, H. apargioides, H. gayana, H. spathulata, and H. thrincioides, all of which are distributed in central-south Chile and adjacent Argentina. Morphometric and molecular (AFLP) data were used to help reveal processes involved in the evolution of the complex. A total of 54 populations were sampled: 34 were analyzed morphometrically and 45 were examined for genetic variation and divergence using AFLP methodology. Morphometric analysis shows that two species, H. gayana and H. spathulata, are clearly separated phenotypically from the others, but that//, apargioides and H. thrincioides are more similar to each other. The principal environmental conditions influencing morphology and distribution of species in the H. apargioides complex appear to be salinity and elevation in H. spathulata and H. gayana, respectively, and climate in H. apargioides and H. thrincioides. The overall pattern in the evolution of the complex is one of subtle morphological divergence in response to environmental selection, perhaps reflecting initial stages of adaptive radiation. The low level of molecular divergence among species also suggests rapid speciation. [ABSTRACT FROM AUTHOR]

The systematics of the Hypochaeridinae subtribe was re-evaluated based on a combination of published and new molecular data. Newly found clades were additionally characterized using published and new phytochemical data. In addition to flavonoids and sesquiterpene lactones, which had been reviewed recently as chemosystematic markers in the Cichorieae, we analysed the reported occurrences of caffeic acid derivatives and their potential as chemosystematic markers. Our molecular results required further changes in the systematics of the genus Leontodon. Based on previous molecular data, Leontodon s.l.-i.e. including sections Asterothrix, Leontodon, Thrincia, Kalbfussia, and Oporinia (Widder )-had been split into the genera Leontodon s.str. (sections Asterothrix, Leontodon, and Thrincia) and Scorzoneroides (sections Kalbfussia and Oporinia). Instead of splitting Leontodon into even a higher number of segregate genera we propose to include Hedypnois into Leontodon s.str. and here into section Leontodon. Moreover, sections Asterothrix and Leontodon should be merged into a single section Leontodon. The newly defined genus Leontodon is characterised by the unique occurrence of hydroxyhypocretenolides. The monophyly of the genus Hypochaeris is neither supported nor contradicted and potentially comprises two separate molecular clades . The clade Hypochaeris I comprises the majority of the European and Mediterranean as well as all South American taxa of Hypochaeris s.l. while the clade Hypochaeris II encompasses only H. achyrophorus L., H. glabra L., H. laevigata Benth. & Hook.f., and H. radicata L. [ABSTRACT FROM AUTHOR]

The genus Hypochaeris offers an excellent model for studies of recent adaptive radiation in the South American continent. We used karyotype analysis with chromomycin A (CMA)/4',6-diamidino-2-phenylindole (DAPI) banding and fluorescence in situ hybridization (FISH), and amplified fragment length polymorphism (AFLP) fingerprinting to investigate for the first time the Brazilian endemic H. catharinensis and define its position within the South American group of species. Strong CMA-positive signals were seen at the end of both arms of chromosome 3 and at the end of the long arm of chromosome 4. DAPI bands were only detected in subterminal position on short arm of chromosome 4. FISH with 5S and 35S ribosomal DNA (rDNA) probes revealed a single 5S rDNA locus on short arm of chromosome 2, typical for all other South American Hypochaeris taxa analyzed to date. The 35S rDNA locus was identified at subterminal position on the short arm of chromosome 3, as reported so far for only two of the known species ( H. lutea and H. patagonica). The AFLP study included 55 individuals, comprising nine species of the South American Hypochaeris plus their putative ancestor H. angustifolia. Eleven AFLP primer combinations generated a total of 401 fragments, of which 388 (96.7%) were polymorphic. High genetic similarities were observed among taxa, with all South American Hypochaeris species falling into one main cluster [100% bootstrap (BS)]. Hypochaeris catharinensis is closely related to H. lutea (82% BS), forming a well-separated subcluster within the South American species. Taken together, the karyological and AFLP data contribute to the placement of H. catharinensis within the phylogenetic framework of South American species of Hypochaeris and allow the definition of a novel and well-resolved phylogenetic group (the Lutea group). [ABSTRACT FROM AUTHOR]

Seventy horses with clinical evidence of Australian stringhalt were studied in France from 2003 to 2008. All horses but one had history of bilateral stringhalt and grazed pastures infested with Hypochoeris radicata (L.). They displayed hind limbs hyperflexion and an abnormal gait because of a distal axonopathy with a skeletal muscle denervation and atrophy. Fifty percentage of them recovered spontaneously in 8 months, and only the more affected horses were unable to recover even if they looked healthy on dry and hot days. Clinical troubles revealed also depression or aggressive behaviour, suggesting that central nervous system might be affected. Treatment with phenytoin resulted in a rapid noticeable improvement of stringhalt in some horses but the administration of taurine seems to improve behavioural disorders. Deeply affected horses (grade III and more of Huntington's classification at the beginning) must be treated with phenytoin when the weather is muddy and damp because they still display stringhalt when they are afraid or at the beginning of the work. [ABSTRACT FROM AUTHOR]

The prevalent way aphids accomplish colony defense against natural enemies is a mutualistic relationship with ants or the occurrence of a specialised soldier caste typcial for eusocial aphids, or even both. Despite a group-living life style of those aphid species lacking these defense lines, communal defense against natural predators has not yet been observed there. Individuals of Aphis nerii (Oleander aphid) and Uroleucon hypochoeridis, an aphid species feeding on Hypochoeris radicata (hairy cat's ear), show a behavioral response to visual stimulation in the form of spinning or twitching, which is often accompanied by coordinated kicks executed with hind legs. Interestingly, this behaviour is highly synchronized among members of a colony and repetitive visual stimulation caused strong habituation. Observations of natural aphid colonies revealed that a collective twitching and kicking response (CTKR) was frequently evoked during oviposition attempts of the parasitoid wasp Aphidius colemani and during attacks of aphidophagous larvae. CTKR effectively interrupted oviposition attempts of this parasitoid wasp and even repelled this parasitoid from colonies after evoking consecutive CTKRs. In contrast, solitary feeding A. nerii individuals were not able to successfully repel this parasitoid wasp. In addition, CTKR was also evoked through gentle substrate vibrations. Laser vibrometry of the substrate revealed twitching-associated vibrations that form a train of sharp acceleration peaks in the course of a CTKR. This suggests that visual signals in combination with twitching-related substrate vibrations may play an important role in synchronising defense among members of a colony. In both aphid species collective defense in encounters with different natural enemies was executed in a stereotypical way and was similar to CTKR evoked through visual stimulation. This cooperative defense behavior provides an example of a surprising sociality that can be found in some aphid species that are not expected to be social at all. [ABSTRACT FROM AUTHOR]

Abstract: We used Amplified Fragment Length Polymorphism markers (AFLP) and breeding system studies to investigate the population structure and reproductive biology of Hypochaeris angustifolia (Asteraceae: Cichorieae). This species is endemic to altiplanos of the Atlas Mountains (Morocco) where it occurs in scattered populations, and it is the sister species to c. 40 species of this genus in South America. PCoA, NJ, and Bayesian clustering, revealed that the populations are very isolated whilst AFLP parameters show that almost all populations have marked genetic divergence. We contend that these features are more in accord with a vicariance origin for the scattered populations of H. angustifolia, rather than establishment by long-distance dispersal. The breeding system studies revealed that H. angustifolia is a self-incompatible species, with low fecundity in natural and in experimental crosses, probably due to a low frequency of compatible phenotypes within and between the populations. [Copyright &y& Elsevier]

We report the isolation and characterization of eight microsatellite loci for Hypochaeris salzmanniana, an endangered species endemic to the southwestern coast of Spain and the Atlantic coast of Morocco. A total of 32 alleles were detected across a sample of 45 individuals, with an average number of 4.0 alleles per locus. The average polymorphic information content (PIC) was 0.533 and the observed (HO) and expected (HE) heterozygosity values varied from 0.022 to 0.978 and from 0.434 to 0.759, respectively. Five loci exhibited significant deviation from Hardy-Weinberg equilibrium (P ≤ 0.001) and three pairs of loci showed significant linkage disequilibrium (P ≤ 0.01). The eight loci were tested for transferability in three others species (H. arachnoidea, H. glabra, and H. radicata) belonging to the same section of H. salzmanniana. With the exception of locus Hsalz7, all loci successfully amplified in the three species. These preliminary data confirm the usefulness of microsatellite markers for assessing the ecology and genetic structure of H. salzmanniana and to understand the evolution of species within the section Hypochaeris. [ABSTRACT FROM AUTHOR]

We report the phylogeographic pattern of the Patagonian and Subantarctic plant Hypochaeris incana endemic to southeastern South America. We applied amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) analysis to 28 and 32 populations, respectively, throughout its distributional range and assessed ploidy levels using flow cytometry. While cpDNA data suggest repeated or simultaneous parallel colonization of Patagonia and Tierra del Fuego by several haplotypes and/or hybridization, AFLPs reveal three clusters corresponding to geographic regions. The central and northern Patagonian clusters (∼38–51° S), which are closer to the outgroup, contain mainly tetraploid, isolated and highly differentiated populations with low genetic diversity. To the contrary, the southern Patagonian and Fuegian cluster (∼51–55° S) contains mainly diploid populations with high genetic diversity and connected by high levels of gene flow. The data suggest that H. incana originated at the diploid level in central or northern Patagonia, from where it migrated south. All three areas, northern, central and southern, have similar levels of rare and private AFLP bands, suggesting that all three served as refugia for H. incana during glacial times. In southern Patagonia and Tierra del Fuego, the species seems to have expanded its populational system in postglacial times, when the climate became warmer and more humid. In central and northern Patagonia, the populations seem to have become restricted to favourable sites with increasing temperature and decreasing moisture and there was a parallel replacement of diploids by tetraploids in local populations. [ABSTRACT FROM AUTHOR]

Aim To analyse phylogeographic patterns in the four species of Hypochaeris sect. Hypochaeris, evaluating possible areas of origin and the microevolutionary processes that have shaped their morphology, genetics and distribution. Location Western Mediterranean area. Methods We applied amplified fragment length polymorphism (AFLP) markers to a total of 494 individuals belonging to 82 populations of Hypochaeris arachnoidea, H. glabra, H. radicata and H. salzmanniana to determine population structure. Results Populations with the largest proportion of private and rare AFLP fragments were found in Morocco. This region was consequently inferred to be the ancestral area for H. arachnoidea, H. glabra, H. radicata and H. salzmanniana. The Guadalquivir River (southern Spain) was inferred to be an effective dispersal barrier for H. glabra and H. radicata. The Strait of Gibraltar was inferred to be a somewhat weaker barrier than the Guadalquivir River for H. radicata and a much weaker barrier for H. glabra. The main barrier for H. salzmanniana coincides with the extension of the Rif Mountains to the Atlantic coast in Morocco, and the Strait of Gibraltar is a much weaker barrier for this species. Hypochaeris arachnoidea appears to have originated in the Atlas Mountains. Main conclusions The highest levels of genetic variation in La Mamora forest ( H. glabra and H. salzmanniana) or the adjacent central Middle Atlas ( H. arachnoidea and H. radicata) in Morocco suggest that these areas were a centre of origin of Hypochaeris sect. Hypochaeris. All three potential barriers – the Guadalquivir River, the Strait of Gibraltar, and the Rif Mountains – have been important in shaping genetic diversity in species of section Hypochaeris. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to analyze the diversity of Ty1-copia retrotransposons in 18 taxa of Hypochaeris, including two Old World species H. maculata (2n =2x =10) and H. angustifolia (2n =2x =8), and representatives of the South American species (16 accessions of 15 species; all 2n =2x =8). Analysis of 380 PCR-amplified sequences, corresponding to a conserved domain of the subset of Ty1-copia reverse transcriptase (rt) gene amplifiable with degenerate standard primers, showed high levels of intra- and interspecific heterogeneity. Nucleotide diversity (Pi) of the copia fragments was high in all species and varied from 0.229 (H. angustifolia) to 0.412 (H. chillensis). Higher sequence heterogeneity correlates positively with larger genome size among analyzed species. Phylogenetic analyses of amplified fragments revealed different patterns of intraspecific heterogeneity within species, with most sequences forming one well-supported main clade while a few sequences fall into small clades or are left ungrouped. The combined analysis of all sequences revealed the presence of three main clades and showed that highly diverged species contain closely related Tyl-copia group retrotransposons. One of the main clades includes rt sequences of all South American species and three sequences of their putative ancestor, H. angustifolia, but no sequence of the Old World H. maculata. FISH with copia retrotransposons in four Hypochaeris species, including H. maculata and H. angustifolia and New World H. apargioides and H. spathulata, revealed differences in the chromosomal distribution between the two groups. In Old World species copia retroelements are distributed over the whole length of the chromosomes, excluding rDNA sites and some centromeres. In the South American species the two largest chromosome pairs are enriched in copia, while most of the long arms of the two small pairs of chromosomes are devoid of these elements. The patterns of heterogeneity and chromosomal distribution of Ty1-copia retrotransposons in Hypochaeris are discussed in the context of the origin, genome evolution and organization of the South American species. [Copyright &y& Elsevier]

The novel sesquiterpenoid 8α-hydroxyhypoglabric acid (1) was isolated from a methanolic extract of whole plants of Hypochaeris achyrophorus L. The compound was isolated by silica gel column chromatography (CC), repeated Sephadex LH-20 CC, and semi-preparative RP-HPLC. Structure elucidation was accomplished by high resolution mass spectrometry and by 1D- and 2D-NMR spectroscopy. The chemosystematic significance of the new compound is discussed in the context of sesquiterpenoids from other members of the Hypochaeridinae and in the light of recent molecular data on the phylogeny of this group. [ABSTRACT FROM AUTHOR]

To detect potential Pleistocene refugia and colonization routes along the Atlantic coast, we analysed amplified fragment length polymorphisms (AFLPs) in 140 individuals from 14 populations of Hypochaeris salzmanniana (Asteraceae), an annual species endemic to the southwestern European and northwestern African coastal areas. Samples covered the total distributional range of the species, with eight populations in southwestern Spain and six populations in northwestern Morocco. Using nine primer combinations, we obtained 546 fragments in H. salzmanniana and its sister species H. arachnoidea of which 487 (89.2%) were polymorphic. The neighbour-joining tree shows that the populations south of the Loukos river in Morocco are clearly differentiated, having more polymorphic, private, and rare fragments, and higher genetic diversity, than all the other populations. The southernmost populations in Morocco, south of the river Sebou, form a large panmictic population. They are probably the oldest populations that have been relatively unaffected by stochastic processes resulting from Pleistocene glaciations. Northward migration of populations during this period may have resulted in loss of genetic diversity in specific regions, perhaps due to bottlenecks caused by rise in sea level during interglacial periods, and, in some cases, by changes in the breeding system. [ABSTRACT FROM AUTHOR]

The article focuses on the amplified fragment length polymorphism (AFLP) phylogeny of South American Species of Hypochaeris which arrived in South America by dispersal over the Atlantic Ocean from Northwest Africa. AFLP is used to disclosed specific limits and relationships in the South American group of Hypochaeris. The herbaceous genus Hypochaeris L. has an isolated distribution with more than 15 species in the Mediterranean region.

We studied the relationships between self-incompatibility mechanisms and floral parameters in the genus Hypochaeris L. sect. Hypochaeris (consisting of H. glabra, H. radicata, H. arachnoidea, and H. salzmanniana). We assessed at intra- and interspecific levels (1) the self-incompatibility (SI) mechanism and its distribution among populations, (2) the relationship between SI and floral parameters, and (3) the relationship of SI to reproductive success. Hypochaeris salzmanniana is semi-incompatible, H. glabra is self-compatible, and H. arachnoidea and H. radicata are self-incompatible. Floral parameters differed among populations of H. salzmanniana: plants in self-compatible populations had fewer flowers per head, a smaller head diameter on the flower, and a shorter period of anthesis than self-incompatible populations. We also detected this pattern within a semi-compatible population of H. salzmanniana, and these differences were also found between species with different breeding mechanisms. Fruit to flower ratio in natural populations was generally high (>60%) in all species, regardless of breeding system. It is hypothesized that self-compatibility may have arisen through loss of allelic diversity at the S locus due to bottleneck events and genetic drift. [ABSTRACT FROM AUTHOR]

The genus Hypochaeris (Asteraceae, Lactuceae) contains ten species in Europe, three in Asia, and approximately 50 in South America. Previous cytotaxonomic studies have shown two groups of taxa: (1) European species with different basic chromosome numbers and differentiated karyotypes, and (2) South American species with x=4 and uniform asymmetric and bimodal karyotypes. Karyotypic data are synthesized for South American species of Hypochaeris with new information for six Chilean species: H. acaulis, H. apargioides, H. palustris, H. spathulata, H.tenuifolia and H. thrincioides. Four main groups can be distinguished based on presence and localization of secondary constrictions – SCs (bearing Nucleolar Organizer Regions – NORs) on chromosomes 2 and 3, and 18S–25S and 5S rDNA loci number, localization, and activity. We propose karyotypic evolution of South American Hypochaeris (x=4) from H. maculata-like (x=5) European ancestors. The original South American karyotype would have possessed two SCs, one on the long arm of chromosome 2, and the other on the short arm of chromosome 3 (in terminal position). Further evolution would have involved inversion within the short arm of chromosome 3 and inactivation/loss of the SC on chromosome 2. [ABSTRACT FROM AUTHOR]

Abstract: In recent years molecular data, especially from DNA, have provided more precise estimates of relationships among vascular plants. Different types of data have been used efficaciously at different levels of the taxonomic hierarchy from ordinal and familial classifications to genetic variation within populations. The impact on systematics has been enormous, often confirming previous hypotheses established through morphological or other data, but sometimes offering novel and surprising insights. Although it is far from clear which genes or intergenic regions will eventually be known to contain the most helpful phylogenetic information for general and special classification, it is abundantly clear that a genetic yardstick will be used routinely. The impact of molecular data on plant systematics is now having a similar import in biogeography. Sequence data, as well as DNA fingerprinting of various types, are now being employed to assess patterns of isolation and speciation, timing of changes of distributions and speciation events, routes of migration and/or dispersal, population-level divergence, and hybridization. Systematics and biogeography, therefore, are melding together more closely than ever before, because the same kinds of data can be used to address questions regarding evolutionary relationships as well as patterns of distribution in space and time. Data at the populational level are especially helpful in a multidisciplinary context for answering questions regarding infraspecific affinities and for explaining distributions resulting from recent historical and ecological factors. Examples from the genus Hypochaeris (Asteraceae) from southern South America, using DNA sequence and AFLP data, are used to illustrate these points. The genus appears to have originated in Eurasia, dispersed to South America during the past several million years, and radiated into more than 45 species that are adapted to many different ecological regimes. In den letzten Jahren haben molekulare Daten, besonders DNA-Daten, präzisere Einblicke in die Verwandtschaftsbeziehungen zwischen Höheren Pflanzen ermöglicht. Unterschiedliche Datentypen wurden erfolgreich auf verschiedenen taxonomischen Rangstufen verwendet, von Ordnungs- und Familien-Klassifikationen bis hin zu genetischer Variation innerhalb von Populationen. Der Einfluss auf die Systematik war enorm, wobei frühere, von morphologischen oder anderen Daten abgeleitete Hypothesen oft bestätigt wurden, manchmal jedoch neue und überraschende Einblicke resultierten. Obwohl bei weitem noch nicht geklärt ist, welche DNA-Regionen den höchsten phylogenetischen Informationsgehalt für die Klassifikation von Gattungen und Arten enthalten, ist vollkommen klar, dass man in Zukunft einen genetischen Maßstab routinemäßig verwenden wird. Der Einfluss, den molekulare Daten bis jetzt auf die Pflanzensystematik ausgeübt haben, trägt nun in gleicher Weise zur Klärung biogeographischer Fragestellungen bei. So werden Sequenzdaten und verschiedene DNA Fingerprinting-Methoden dazu verwendet, Isolations- und Artbildungsmuster, Migrationsrouten, Verbreitung durch Pollen und Samen, Differenzierung von Populationen und Hybridisierung zu erforschen. Systematik und Biogeographie verschmelzen enger als je zuvor, weil dieselben Daten verwendet werden, um evolutionäre Verwandtschaftsverhältnisse und Verteilungsmuster in Raum und Zeit zu untersuchen. Daten auf dem Populationsniveau sind in einem multidisziplinären Zusammenhang besonders hilfreich, um zwischenartliche Verwandtschaftsverhältnisse zu untersuchen und Verteilungen zu erklären, die aus historischen und ökologischen Faktoren resultieren. Um diese Punkte zu illustrieren, verwenden wir DNA Sequenz- und AFLP-Daten anhand des Beispiels der Gattung Hypochaeris (Asteraceae) aus dem südlichen Südamerika. Es scheint, dass diese Gattung in Eurasien entstanden ist, innerhalb der letzten Millionen Jahre nach Südamerika vorgedrungen ist und dort eine Radiation in mehr als 45 Arten durchgemacht hat, die an viele verschiedene ökologische Nischen adaptiert sind. [Copyright &y& Elsevier]

The typification of the name Hypochaeris maculata L. is discussed. A specimen from the Linnaean Herbarium (LINN) is designated as the lectotype. [ABSTRACT FROM AUTHOR]

In february 2012 floral collections were made at Uspallata hills (Mendoza) and South Callingasta department (San Juan). Taxonomical identification from herborized plants and information searches in data bases allowed us to confirm the presence of Pastinaca sativa L. in San Juan province just like Hypochaeris tenerifolia (J. Rèmy) Dusén and Solanum tweedianum Hook. in Mendoza province. [ABSTRACT FROM AUTHOR]