Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes.

INTRODUCTION: Ptaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all-over the World and is under suspicion of causing human cancers. OBJECTIVE: To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. METHODOLOGY: PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after forced reaction into PtB. Optimal reaction conditions were tested using hydrochloric acid, sulphuric acid, trifluoroacetic acid (TFA), acetic acid and temperature as the experimental variables. A pair-wise test for PTA degradation in plant-press were used to explore the effect of this preservation regime. A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. RESULTS: An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. CONCLUSION: Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification. Copyright © 2017 John Wiley & Sons, Ltd.

A novel technique for determination of the fructose, glucose and sucrose distribution in nectar from orchids by HPLC-ELSD.

The dominant components in floral nectar is fructose, glucose and sucrose. The concentration and the ratio between the sugars are indicative for plant species and play an important part in the interplay between plants and pollinators. In this paper we present a novel HPLC-ELSD based analytical method for sugar characterization of nectar from orchids. Nectar was collected on Whatman No. 1 paper and preserved in the field by 70 v/v% ethanol. The analytical method had a linear range up to at least 3000 mg L-1 for all 3 sugars with a precision of 1.5-1.7%. Correlation coefficients were 0.9999 to 1.0000. The LOD of all sugars were 5-7 mg L-1 and the LOQ were 17-19 mg L-1. Field samples were stable for min. 7 weeks at -18 °C. The technique was applied to two species of Platanthera (Orchidaceae) in order to test whether species-related differences in sugar composition could be observed. No differences were found between the two species, which were sucrose-dominant (53.5-100%) though with high variation within species and between individual flowers.

PESI - a taxonomic backbone for Europe.

BACKGROUND: Reliable taxonomy underpins communication in all of biology, not least nature conservation and sustainable use of ecosystem resources. The flexibility of taxonomic interpretations, however, presents a serious challenge for end-users of taxonomic concepts. Users need standardised and continuously harmonised taxonomic reference systems, as well as high-quality and complete taxonomic data sets, but these are generally lacking for non-specialists. The solution is in dynamic, expertly curated web-based taxonomic tools. The Pan-European Species-directories Infrastructure (PESI) worked to solve this key issue by providing a taxonomic e-infrastructure for Europe. It strengthened the relevant social (expertise) and information (standards, data and technical) capacities of five major community networks on taxonomic indexing in Europe, which is essential for proper biodiversity assessment and monitoring activities. The key objectives of PESI were: 1) standardisation in taxonomic reference systems, 2) enhancement of the quality and completeness of taxonomic data sets and 3) creation of integrated access to taxonomic information. NEW INFORMATION: This paper describes the results of PESI and its future prospects, including the involvement in major European biodiversity informatics initiatives and programs.

Patterns of polyploid evolution in Greek marsh orchids (Dactylorhiza; Orchidaceae) as revealed by allozymes, AFLPs, and plastid DNA data.

Polyploidy is common in higher plants, and speciation in polyploid complexes is usually the result of reticulate evolution. We examined variation in nuclear AFLP fingerprints, nuclear isozymes, and hypervariable plastid DNA loci to describe speciation patterns and species relationships in the Dactylorhiza incarnata/maculata polyploid complex (marsh orchids; Orchidaceae) in Greece. Several endemic taxa with restricted distribution have been described from this area, and to propose meaningful conservation priorities, detailed relationships need to be known. We identified four independently derived allopolyploid lineages, which is a pattern poorly correlated with prevailing taxonomy. Three lineages were composed of populations restricted to small areas and may be of recent origins from extant parental lineages. One lineage with wide distribution in northern Greece was characterized by several unique plastid haplotypes that were phylogenetically related and evidently older. The D. incarnata/maculata polyploid complex in Greece has high levels of genetic diversity at the polyploid level. This diversity has accumulated over a long time and may include genetic variants originating from now extinct parental populations. Our data also indicate that the Balkans may have constituted an important refuge from which northern European Dactylorhiza were recruited after the Weichselian ice age.