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The genus Hypochaeris was likely introduced into South America by a unique long-distance dispersal event from an ancestral Northwest African species, with subsequent radiation and diversification throughout the temperate zones of the continent. Hypochaeris catharinensis is an endemic species of Southern Brazil growing mostly in high-elevation grasslands with dry, rocky, and shallow soils. Here, we used nine microsatellite loci and a total sample of 441 individuals to assess genetic variability patterns within and among 13 H. catharinensis populations. The results showed a total of 215 alleles in the nine loci tested, the expected and observed heterozygosities average were 0.31 and 0.43, respectively, and allelic richness varied from 4.09 to 7.23. The levels of allelic richness showed that genetic variability is maintained by gene flow, thus ensuring that these populations are not genetically isolated. We found no correlation between geographic and genetic distances, with high levels of genetic variability within, rather than among, populations. The low levels of genetic structure in the species are consistent with recent evolutionary processes of the Hypochaeris genus in South America; after adaptive radiation and species differentiation, dispersal to similar habitats led to the establishment of new populations. Along with initial founder effects, the existence of gene flow explains the current genetic variation across the H. catharinensis populations. In addition, historic environmental changes reported for Southern Brazil may explain the current clustered distribution of the species. [ABSTRACT FROM AUTHOR]

Capsicum baccatum is one of the main pepper species grown and consumed in South America. In Brazil, it is commonly cultivated by family farmers, using mostly the genotypes bishop's hat genotypes (locally cambuci) and red chili pepper (dedo-de-moça). This study had the objective of characterizing 116 C. baccatum accessions from different regions of Brazil, based on morphological fruit descriptors and AFLP (Amplified Fragment Length Polymorphisms) markers. Broad phenotypic variability among the C. baccatum accessions was detected when using morphological fruit descriptors. The Ward modified location model (Ward-MLM) discriminated five groups, based mainly on fruit shape. Six combinations of AFLP primers detected polymorphism in 97.93% of the 2466 identified bands, indicating the high genetic variability in the accessions. The UPGMA coincided with the Bayesian clustering analysis and three large groups were formed, separating the wild variety C. baccatum var. praetermissum from the other accessions. There was no relation between genetic distance and geographical origin of the accessions, probably due to the intense exchange of fruits and seeds between farmers. Morphological descriptors used together with AFLP markers proved efficient in detecting the levels of genetic variability among the accessions maintained in the germplasm collections. These results can be used as an additional source of helpful information to be exploited in C. baccatum breeding programs. [ABSTRACT FROM AUTHOR]

Differences in habitat, geographical distribution and minor details related to floral and vegetative structures of Petunia spp. have led to many changes in the taxonomy of the genus. In the face of controversy relating to species circumscription in the genus and insufficient variation to identify the evolutionary relationships among Petunia spp. using conventional molecular phylogenetic markers, the purpose of this work was to investigate the potential and limitations of amplified fragment length polymorphism (AFLP) data analyses for delimiting species and inferring evolutionary relationships in a young group, providing the bases for future studies. We analysed 152 individuals distributed randomly across the geographical range of 14 Petunia taxa. AFLP analysis resulted in 1259 polymorphic fragments that proved to be efficient in identifying high numbers of polymorphisms in recently diverged plant species. The phylogenetic approach using AFLP allowed a high level of correct assignment of individuals to their corresponding morphological groups. The results of the genetic clustering analyses were consistent with respect to the main groups and the well-supported relationships in phylogenetic analyses. In this study, we demonstrated the efficiency of AFLP to identify polymorphisms in recently diverged lineages of Petunia. We report that this approach was also valuable in species delimitation for species status of difficult taxa and indicating new species. [ABSTRACT FROM AUTHOR]

Background and Aims Sexually deceptive orchids of the genus Ophrys use mimicry of pollinator females to attract specific pollinators. Pollinator shifts may drive speciation in Ophrys, since novel pollinators may in principle act as isolating factors immediately. It is thus possible that evolution of novel species occurs rapidly and with a progenitor–derivative pattern. The aims of this study are to compare genetic structure and diversity among widespread and geographically restricted Ophrys taxa, to test whether genetic structure is associated with specific pollinators, and to investigate whether any widespread species may have acted as a progenitor for the evolution of more restricted taxa. Methods Genetic differentiation and diversity were investigated in O. leucadica and O. cinereophila, the two taxa of the Ophrys fusca sensu lato complex widespread in the Aegean, and three geographically restricted taxa from Rhodes, O. attaviria, O. parvula and O. persephonae, all differing in their specific pollinators. This was done using amplified fragment length polymorphism (AFLP) DNA fingerprinting, and sequencing of the low-copy nuclear gene LEAFY (LFY). Key Results All taxa were found to be separate genetic entities, with O. leucadica forming two geographic groups from the west and east of the Aegean. Genetic structure was significantly shaped by pollinators and geography, and comparison of sequence and AFLP data revealed ancestral polymorphisms shared among several taxa. Among the sampled taxa, O. leucadica harbours the greatest genetic differentiation and geographic structure, and the highest genetic diversity. Part of the genome of O. parvula, endemic to Rhodes, may be derived from O. leucadica. Conclusions Pollinators probably influence the genetic structure of the investigated Ophrys species. The genetic pattern identified is consistent with O. leucadica being the oldest of the sampled taxa, making O. leucadica a candidate progenitor species from which more restricted taxa such as O. parvula may have evolved. [ABSTRACT FROM AUTHOR]

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]

Ophrys iricolor and O. mesaritica are a pair of morphologically similar, closely related sexually deceptive orchids from the eastern Mediterranean. Ophrys iricolor is known to be pollinated by Andrena morio males and the specific pollinator of Ophrys mesaritica is determined as Andrena nigroaenea. Amplified fragment length polymorphism revealed O. iricolor and O. mesaritica to be genetically intermixed on the whole, although populations of O. iricolor and O. mesaritica in geographical proximity are strongly differentiated, suggesting that specific pollinators locally differentiate these taxa. Based on the available biological data and the system of pollinator attraction operative in Ophrys, we hypothesize that O. mesaritica may have arisen from O. iricolor by pollinator shift and that this is more probable than scenarios invoking hybridization as a result of mispollination by rare, non-specific flower visitors or specifically attracted insects. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 583–598. [ABSTRACT FROM AUTHOR]

The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.I., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly. [ABSTRACT FROM AUTHOR]

Provides information on a study reporting the discovery of a male-specific DNA fragment in the perennial diploid dioecious species Atriplex garrettii. Methodology and materials used to conduct the study; Results of the study; Discussion on the results.

• Premise of the study: Hypochaeris is considered a biological model to understand evolutionary processes in the vascular flora of South America, particularly from the temperate portion of the continent. We report the development and characterization of microsatellite markers for H. chillensis to assess the genetic variability and patterns of population structure of the species. • Methods and Results: Twelve microsatellite primers were isolated using a CT- and GT-enriched genomic library. PCR amplification detected one to five alleles, with 2.91 alleles per locus on average. Tested for cross-amplification, all primer pairs were successfully amplified in 10 South American species and in the putative ancestor of the group, H. angustifolia. • Conclusions: The microsatellites can be used to assess genetic diversity and population structure of H. chillensis. Application in other species will focus on the elucidation of adaptive radiation of the genus in South America. [ABSTRACT FROM AUTHOR]