163 research outputs found
Unexpected impacts of climate change on Alpine vegetation
The vegetation in a high alpine site of the European Alps experienced changes in area between 1953 and 2003 as a result of climate change. Shrubs showed rapid expansion rates of 5.6% per decade at altitudes between 2400 m and 2500 m. Above 2500 m, vegetation coverage exhibited unexpected patterns of regression associated with increased precipitation and permafrost degradation. As these changes follow a sharp increase in both summer and annual temperatures after 1980, we suggest that vegetation of the alpine (2400-2800 m) and nival (above 2800 m) belts respond in a fast and flexible way, contradicting previous hypotheses that alpine and nival species appear to have a natural inertia and are able to tolerate an increase of 1-2 degrees C in mean air temperature
Molecular approach to assess the origin of cv. Marzemino
DNA marker analysis was used to determine the varietal identity of Marzemino accessions in public collections and private Italian vineyards; relationships among this varietal group and Vertzami, a traditional Greek cultivar, were also investigated through SSR and AFLP approaches. Molecular results strongly support the relationship among Vertzami cultivars growing in Greece, Marzemino and several Italian accessions selected on the basis of etymological similarity. SSR data exclude a direct descent of Marzemino, or other related Italian varieties, from Vertzami; on the other hand the level of similarity among Vertzami, Marzemino and some related varieties indicates a possible common ancestor. None of the accessions is considered as common ancestor but on the basis of genomic variability in the Marzemino group and of the relationships with the other Italian cultivars a probable Italian ancestor is supposed.
Evolutionary, ecological and biotechnological perspectives on plasmids resident in the human gut mobile metagenome
Numerous mobile genetic elements (MGE) are associated with the human gut microbiota and collectively referred to as the gut mobile metagenome. The role of this flexible gene pool in development and functioning of the gut microbial community remains largely unexplored, yet recent evidence suggests that at least some MGE comprising this fraction of the gut microbiome reflect the co-evolution of host and microbe in the gastro-intestinal tract. In conjunction, the high level of novel gene content typical of MGE coupled with their predicted high diversity, suggests that the mobile metagenome constitutes an immense and largely unexplored gene-space likely to encode many novel activities with potential biotechnological or pharmaceutical value, as well as being important to the development and functioning of the gut microbiota. Of the various types of MGE that comprise the gut mobile metagenome, plasmids are of particular importance since these elements are often capable of autonomous transfer between disparate bacterial species, and are known to encode accessory functions that increase bacterial fitness in a given environment facilitating bacterial adaptation. In this article current knowledge regarding plasmids resident in the human gut mobile metagenome is reviewed, and available strategies to access and characterize this portion of the gut microbiome are described. The relative merits of these methods and their present as well as prospective impact on our understanding of the human gut microbiota is discussed
Karyotype characterization and nuclear DNA content measurement in Bromeliaceae: State of the art and future perspectives
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
The use of fluorescent probes to assess viability of the plant pathogenic bacterium Clavibacter michiganensis subsp. michiganensis by flow cytometry
Guida Botanica al Parco Alto Garda Bresciano
Un invito a scoprire le splendide attrattive botaniche del Parco Alto Garda Bresciano, dal lago alle cime più alte.
Dopo una colloquiale introduzione sulle peculiarità della vita vegetale, si prosegue osservando l’affascinante interazione tra le piante, l’uomo e le caratteristiche fisiche e climatiche del territorio, fino a delineare una sintesi paesaggistica che pone in relazione la varietà di habitat con l’eccezionale ricchezza floro-vegetazionale del Parco Alto Garda Bresciano.
Più di 900 illustrazioni aiuteranno a riconoscere le piante e le comunità vegetali delle diverse unità di paesaggio. Le note escursionistiche consentiranno, inoltre, di osservare direttamente tutte le tipologie vegetazionali descritte, nonché tutte le piante più rappresentative dell’Alto Garda Bresciano
Photothermal-assisted antibacterial application of graphene oxide-Ag nanocomposites against clinically isolated multi-drug resistant Escherichia coli
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