Was Charles Darwin right in his explanation of the ‘abominable mystery’?

The site and time of origin of angiosperms are still debated. The co-occurrence of many of the early branching lineages of flowering plants in a region somewhere between Australia and the SW Pacific islands suggests a possible Gondwanan origin of angiosperms. The recent recognition of Zealandia, a 94% submerged continent in the east of Australia, could explain the discrepancy between molecular clocks and fossil records about the age of angiosperms, supporting the old Darwinian hypothesis of a “lost continent” to explain the “abominable mystery” regarding the origin and rapid radiation of flowering plants

Crop changes from the XVI century to the present in a hill/mountain area of eastern Liguria (Italy)

<p>Abstract</p> <p>Background</p> <p>Chronological information on the composition and structure of agrocenoses and detailed features of land cover referring to specific areas are uncommon in ethnobotanical studies, especially for periods before the XIX century. The aim of this study was to analyse the type of crop or the characteristics of soil cover from the XVI century to the present.</p> <p>Methods</p> <p>This diachronic analysis was accomplished through archival research on the inventories of the Parish of St. Mary and those of the Municipality of Pignone and from recent surveys conducted in an area of eastern Liguria (Italy).</p> <p>Results</p> <p>Archival data revealed that in study area the primary means of subsistence during the last five centuries, until the first half of the XX century, was chestnuts. In the XVIII and XIX centuries, crop diversification strongly increased in comparison with previous and subsequent periods. In more recent times, the abandonment of agricultural practices has favoured the re-colonisation of mixed woodland or cluster-pine woodland.</p> <p>Conclusion</p> <p>Ancient documents in the ecclesiastic or municipal inventories can be a very useful tool for enhancing the knowledge of agricultural practice, as well as of subsistence methods favoured by local populations during a particular time and for reconstructing land use change over time.</p

Resolution of Viable and Membrane-Compromised Free Bacteria in Aquatic Environments by Flow Cytometry

International audienceIn aquatic environments, free heterotrophic bacteria play an extremely important role due to their high biomass, wide panel of metabolisms, and ubiquity, as well as the toxicity of certain species. This unit presents a nucleic‐acid double‐staining protocol (NADS) for flow cytometry that can distinguish fractions of viable, damaged, or membrane‐compromised cells within the free‐bacterial community. The NADS protocol is based on the simultaneous utilization of two nucleic acid stains—membrane‐permeant SYBR Green and membrane‐impermeant propidium iodide (PI). The efficiency of the double staining on fresh samples is magnified by the FRET from SYBR Green to PI when both are bound to the nucleic acids. Full quenching of SYBR Green fluorescence by PI identifies cells with a compromised membrane, partial quenching indicates cells with a slightly damaged membrane, and lack of quenching characterizes cells with an intact membrane. Samples do not require any pretreatment and this protocol can be performed almost anywhere

Population structure and genetic diversity of the threatened quillwort Iso\uebtes malinverniana and implication for conservation

62010 GENR 1reservedInternationalItalian coauthor/editorThe goal of this research was to investigate genetic variation inIsoëtes malinverniana(Isoëtaceae) to select candidate populations for future conservation efforts. To this aim, ISSR and AFLP analyses, carried out using six and four primer combinations, respectively, produced a total of 425 bands, 97.18% of which were polymorphic. Our results suggest thatI. malinverniana shows medium to high genetic diversity (mean Nei’s genetic diversity: H= 0.1491 for ISSR data; H= 0.2289 for AFLP data) and a substantial amount of gene flow between the analysed populations (Nm = 1.768, with combined ISSR and AFLP data). Themoderate levels of population differentiation support the hypothesis that the fragmentation and isolation ofI. malinverniana occurred only recently, probably due to the intensive agriculture practice and water pollution. These results will be used to focus further studies aimed at supporting reintroduction programs within suitable sites of the distribution area.restrictedGentili, R.; Abeli, T.; Rossi, G.; Li, M.; Varotto, C.; Sgorbati, S.Gentili, R.; Abeli, T.; Rossi, G.; Li, M.; Varotto, C.; Sgorbati, S