Phylogeny of helieae (gentianaceae): resolving taxonomic chaos in a neotropical clade

The monophyletic and Neotropical tribe Helieae of the worldwide family Gentianaceae (Gentianales, Asterids, Angiospermae) is well known for its problematic generic classifications. An initial phylogenetic analysis of Helieae shed light onto the relationships between genera, and indicated that traditional generic limits did not correspond to monophyletic groups. In order to obtain a more thorough understanding of generic relationships within the group, we enhanced sampling within the so-called Symbolanthus clade and performed phylogenetic analyses from DNA sequences from one plastid region (matK) and two nuclear regions (ITS and 5S-NTS), plus 112 morphological characters, which were analyzed separately and in combination, using parsimony and Bayesian approaches. A total of 83 individuals representing 20 genera and 51 species of Helieae were sampled; 13 species were included in this study solely based on their morphological characters. Ancestral character reconstructions were performed to identify potential synapomorphies of clades and patterns of homoplasy in the morphological dataset. Our results demonstrate that Prepusa is sister to the remainder of Helieae. Furthermore, the Macrocarpaea clade, the Irlbachia clade and the Symbolanthus clade were also recovered. Within the Symbolanthus clade, our results confirm that Calolisianthus and Chelonanthus are not monophyletic, and also contest the monophyly of Irlbachia as currently circumscribed. Specifically, two species of Calolisianthus group with the type species of Chelonanthus, while the other Calolisianthus species are more closely related to Tetrapollinia and Symbolanthus. Moreover, the green-white-flowered Chelonanthus species and Adenolisianthus are undoubtedly related to Helia and several analyses support Irlbachia pratensis as more closely related to the lineage including the type species of Chelonanthus described above The addition of new characters and taxa led to higher confidence in the relative position of some clades, as well as provided further support for a new generic circumscription of Calolisianthus, Chelonanthus, and Helia. Even though several morphological characters traditionally used in the taxonomy of the group were shown to be homoplasious, most clades can be diagnosed by a combination of morphological character states10619220

Non-developing ascospores in apothecia of asexually reproducing lichen-forming fungi

The presence of apothecia in mixed species (vegetatively reproducing lichens, occasionally producing ascomata) has been interpreted as a mechanism to increase genetic variability in mostly clonal populations. However, spore viability from these apothecia has not been studied. We asked whether ascospores of the mixed species Physconia grisea are viable and thereby contribute to increasing the genetic diversity within populations of this species. An ontogenetic study of spores in cultures of P. grisea and a related sexual species (P. distorta), showed that although mature apothecia from both species produced and discharged meiospores capable of germination, spores from P. grisea were only rarely (0.43 %) able to continue development whereas those from P. distorta germinated and developed successfully. The strongly reduced viability of P. grisea spores suggested that they do not have a strong reproductive function, at least in the two local populations analyzed. Additionally, we show that the segregation of Physconia grisea ssp. lilacina does not have molecular support. [Int Microbiol 2013; 16(3):XXX-XXX]Keywords: Physconia spp. · apothecia · sexual reproduction · germination · ontogenetic development · mixed specie

New records and range extension of a Brazilian Amazon white-sand endemic species: Roraimaea aurantiaca Struwe, S.Nilsson & V.A.Albert (Gentianaceae)

Roraimaea aurantiaca Struwe, S.Nilsson & V.A.Albert, a white-sand endemic species, was previously known from only two specimens collected in Roraima state, Brazil. Our new field collections and re-identified herbarium specimens expand this species’ distribution and include the first records from the Brazilian state of Amazonas. Based on this effort, we present a distribution map, preliminary conservation status of Endangered, the first photographs of living plants, and an updated morphological description. This study aggregates new information on the flora of the northern Amazon Basin, in addition to discussing conservation of R. aurantiaca

In vitro and in vivo antimalarial activity and cytotoxicity of extracts, fractions and a substance isolated from the amazonian plant tachia grandiflora (Gentianaceae)

Tachia sp. are used as antimalarials in the Amazon Region and in vivo antimalarial activity of a Tachia sp. has been previously reported. Tachia grandiflora Maguire and Weaver is an Amazonian antimalarial plant and herein its cytotoxicity and antimalarial activity were investigated. Spectral analysis of the tetraoxygenated xanthone decussatin and the iridoid aglyone amplexine isolated, respectively, from the chloroform fractions of root methanol and leaf ethanol extracts was performed. In vitro inhibition of the growth of Plasmodium falciparum Welch was evaluated using optical microscopy on blood smears. Crude extracts of leaves and roots were inactive in vitro. However, chloroform fractions of the root and leaf extracts [half-maximal inhibitory concentration (IC50) = 10.5 and 35.8 μg/mL, respectively] and amplexine (IC50 = 7.1 μg/mL) were active in vitro. Extracts and fractions were not toxic to type MRC-5 human fibroblasts (IC50 > 50 μg/mL). Water extracts of the roots of T. grandiflora administered by mouth were the most active extracts in the Peters 4-day suppression test in Plasmodium berghei-infected mice. At 500 mg/kg/day, these extracts exhibited 45-59% inhibition five to seven days after infection. T. grandiflora infusions, fractions and isolated substance have potential as antimalarials

Voucher Specimens are Essential for Documenting Source Material Used in Medicinal Plant Investigations

Plant-based natural products research is conducted using a wide variety of source material. The plant material is often obtained directly from the wild, from cultivated plants originally obtained from the wild, or purchased in raw or processed forms. In plant science a voucher specimen usually consists of a pressed, dried herbarium specimen with detailed collection data and serves as a record of an individual plant in time and space. This review article describes why vouchering is necessary and documents actual examples of how improper vouchering can result in serious problems. The primary reason for vouchering is to have a permanent record documenting the material that was used in a particular study. If a specimen is not saved or is not made available to others, the true identity of the plant materials used in a research project may be questioned. Due to the morphological and chemical complexities of interspecific hybrids, within-species variation, and the difficulty associated with identifying species in certain plant genera, the preservation of vouchers is essential for the documentation of the identity and source of such plant material. The use of best practices in specimen preparation is critical for successful documentation. The lack of proper voucher specimens for some research projects has led to serious problems, such as the inability to reproduce critical results, the association of chemical data with the wrong genus and species, and even the complete rejection of the published research results. In cases where plant material was initially misidentified and properly prepared voucher specimens were available, the identities of the research material were eventually corrected and the data was subsequently associated with the correct species, retaining the inherent scientific value of the research