About: Gentiana is a research topic. Over the lifetime, 328 publications have been published within this topic receiving 4262 citations. The topic is also known as: gentian & gentian flower.
Papers published on a yearly basis
TL;DR: Full length cDNA clones of flavonoids 3',5'-hydroxylase, dihydroflavonol 4-reductase and flavonoid 3-glucosyltransferase were cloned from petals of Gentiana triflora and enzymatically characterized by expressing cDNAs in heterologous expression systems.
Abstract: Full length cDNA clones of flavonoid 3',5'-hydroxylase, dihydroflavonol 4-reductase and flavonoid 3-glucosyltransferase were cloned from petals of Gentiana triflora. Their sequences were homologous to counterparts from other plants. Flavonoid 3',5'-hydroxylase and flavonoid 3-glucosyltransferase were enzymatically characterized by expressing cDNAs in heterologous expression systems.
TL;DR: A significant correlation between gene expression and pigment accumulation has been found, indicating that flavonoid biosynthesis during gentian flower development is regulated by temporal expression of these genes.
Abstract: The cDNA clones encoding homologues of flavanone 3-hydroxylase (F3H), anthocyanidin synthase (ANS), flavonoid 3′-hydroxylase (F3′H) and flavone synthase II (FSII) genes were isolated from petals of Gentiana triflora Deduced amino acid sequences exhibited 60–80% identities with the corresponding sequences from other dicotyledonous species Southern blot analysis showed that they were present as multiple copies in the gentian genome, and Northern blot analysis showed that the flavonoid biosynthesis-related genes could be classified into three groups by their temporal expression patterns during gentian flower development The first included chalcone synthase (CHS) and chalcone isomerase (CHI) expressing during all flower development stages; the second included F3′H and FSII expressing at flower early developmental stages; and the third included F3H, flavonoid 3′,5′-hydroxylase (F3′,5′H), dihydroflavonol 4-reductase (DFR), ANS, UDP-glucose:flavonoid 3-O-glucosyltransferase (3GT) and anthocyanin 5-aromatic acyltransferase (5AT) expressing at flower late developmental stages In general, low or undetectable levels of expression were observed in both the leaves and stems High performance liquid chromatography (HPLC) analysis revealed that flavone accumulates from the early flower bud stage, but anthocyanin accumulation peaked at the later flower anthesis stage A significant correlation between gene expression and pigment accumulation has been found, indicating that flavonoid biosynthesis during gentian flower development is regulated by temporal expression of these genes
TL;DR: Phylogenetic relationships between the European species of the genus Gentiana L. (Gentianaceae) were inferred from chloroplast trnL (UAA) intron sequence data to suggest a rapid radiation following the colonization of Europe and that cpDNA can violate assumptions of rate constancy at lower taxonomic level.
Abstract: Phylogenetic relationships between the European species of the genus Gentiana L. (Gentianaceae) were inferred from chloroplast trnL (UAA) intron sequence data. The phylogeny obtained is largely in accordance with the classification of species into sections Gentiana, Megalanthe and Calathianae. Few synapomorphies support the branching of the main lineages and thus could suggest a rapid radiation following the colonization of Europe. Within section Gentiana, our results are highly congruent with the previous distinction of G. montserratii Vivant from G. lutea L. Section Megalanthe is divided into two well separated lineages, both of which comprise calcicole and calcifuge species. The 'star phylogeny' obtained in section Calathianae suggests that most of the taxa speciated almost simultaneously. Relative-rate tests between two lineages suggested that section Chondrophyllae displays higher mutation rates than the rest of the genus Gentiana and that cpDNA can violate assumptions of rate constancy at lower taxonomic level. (C) 1996 The Linnean Society of London.
TL;DR: This study depicts the origin and dispersal routes of this alpine genus, and the role of the uplift of the Qinghai–Tibet Plateau and past climate changes as triggers for its diversification.
Abstract: Aim We investigated the historical biogeography and diversification of Gentiana L. (Gentianaceae). Our study depicts the origin and dispersal routes of this alpine genus, and the role of the uplift of the Qinghai–Tibet Plateau (QTP) and past climate changes as triggers for its diversification. Location Tibeto-Himalayan region and world-wide mountain habitats. Methods Our sampling represents more than 50% of the extant Gentiana species, including all sections across their entire geographical ranges. We investigated the evolutionary history of Gentiana using phylogenetic reconstructions (maximum likelihood and Bayesian inference) of ITS, atpB–rbcL and trnL–trnF sequences, as well as molecular dating with beast. We tested two approaches of ancestral area reconstructions (DEC, DIVA) in BioGeoBEARS and investigated diversification rates using BAMM. Results The common ancestor of Gentiana and subtribe Gentianinae lived in the QTP region at around 34 (25–45) million years ago (Ma), and 40 (29–52) Ma respectively. From the surroundings of the QTP, Gentiana lineages dispersed to eastern China, Taiwan, Europe, North and South America, Australia and New Guinea, from mid-Miocene onward (c. 15 Ma–present), with only one older dispersal event to Europe (c. 37–21 Ma). Diversification rates gradually increased over time, and two switches of diversification rates were identified in Gentianinae (c. 7 Ma, simultaneously in the Pneumonanthe/Cruciata lineage and in Tripterospermum). Main conclusions Gentiana existed in the QTP region throughout most of its uplift history following the India-Asia collision. This region acted as the primary source area for dispersals to many areas of the world. Because steady increase in diversification rates coincides with the extension of the QTP, we argue that the museum theory rather than the explosive radiation theory prevails for gentians in this region, although rare shifts of diversification rates are associated with niche shifts across the alpine/subalpine ecotone.
TL;DR: The results indicate that within a relatively small area with similar soil and climatic conditions, the host plant species can have a major influence on the AMF communities within the roots of Gentiana verna and G. acaulis.
Abstract: The community composition of arbuscular mycorrhizal fungi (AMF) was analyzed in roots of Gentiana verna, Gentiana acaulis, and accompanying plant species from two species-rich Swiss alpine meadows located in the same area. The aim of the study was to elucidate the impact of host preference or host specificity on the AMF community in the roots. The roots were analyzed by nested PCR, restriction fragment length polymorphism screening, and sequencing of ribosomal DNA small-subunit and internal transcribed spacer regions. The AMF sequences were analyzed phylogenetically and used to define monophyletic sequence types. The AMF community composition was strongly influenced by the host plant species, but compositions did not significantly differ between the two sites. Detailed analyses of the two cooccurring gentian species G. verna and G. acaulis, as well as of neighboring Trifolium spp., revealed that their AMF communities differed significantly. All three host plant taxa harbored AMF communities comprising multiple phylotypes from different fungal lineages. A frequent fungal phylotype from Glomus group B was almost exclusively found in Trifolium spp., suggesting some degree of host preference for this fungus in this habitat. In conclusion, the results indicate that within a relatively small area with similar soil and climatic conditions, the host plant species can have a major influence on the AMF communities within the roots. No evidence was found for a narrowing of the mycosymbiont spectrum in the two green gentians, in contrast to previous findings with their achlorophyllous relatives.