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Abstract Chemotaxonomy of the genus Salicornia in the north-adriatic coasts. — Serological and chemical methods have been applied to investigate the systematics of Salicornia, a genus of halophilous Chenopodiaceae where cleistogamy is frequent. The research, limited to north-adriatic material, involved 13 populations (Tab. 1) belonging to all presently known italian taxa: the tetraploid (2n=36) S. veneta; a newly found triploid form (2n=27); a set of diploid forms (2n=18) which range morphologically from S. europaea-like to S. ramosissima-like populations. The aim of the research is to attempt a systematic ordination of these forms, with special emphasis on the strongly polymorphic diploid complex. From all populations a large number of individuals were sampled randomly and the soluble proteins extracted from the mature seeds. The extracts have been used for electrophoresis and for immunization of rabbits: antisera for five populations have been obtained and tested against all extracts (Figs. 1–5). The possibility of distinguishing at the level of population by means of the analysis of seed proteins has been demonstrated. No specific proteins of any populations could be found, as all populations appear to have the same complex of antigens; however, differences in the quantity of individual proteins (Tab. 2) and in the electrophoretic mobility of immunologically equivalent proteins have been observed in the different populations. The electrophoretic strips (Fig. 6) have been examined with numerical methods (Tab. 3 and 4, Figs. 7 and 8) to try a systematic assessment of the material. It risulted that the electrophoretic characters are distributed without correlations one with another; the same is true for the serological characters; ordering based on serological or electrophoretic characters results in a cline; also, the ordinations based on these chemical characters do not correspond one with the other, nor with ordinations based on morphology, on geographic distribution, on ecology. Because of the particular distribution of the characters a systematic assessment of the group appears to be impossible; this distribution is supposed to be due to the frequent cleistogamy and perhaps to apomixis; therefore any attempt to subdivide systematically the group leads to divide as far as to pure line, or to clone. On this basis it is proposed to consider the complex of diploid forms as a single taxonomic unit. 相似文献
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Prof Maria Cengia Sambo 《Plant biosystems》2013,147(3):437-455
Riassunto L'A. studia N. 87 entità di licheni raccolti nell'A. O. I. da ufficiali della Milizia Nazionale Forestale. Fra essi ci sono nuove per la scienza due specie: Chaenothecopsis africana, Theloschistes Sennii e 8 fra varietà e forme; molti sono nuovi per l'A.O.I. e per il Continente africano. 相似文献
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Prof. Tiziano Provasi 《Plant biosystems》2013,147(3-4):267-283
Riassunto L'A., in questa prima parte del suo studio delle torbiere italiane, ne fa un minuzioso elenco, con indicazioni topografiche e richiami bibliografici. 相似文献
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Dott. Onorato Verona 《Plant biosystems》2013,147(3):534-537
Abstract Helianthemetea guttati communities are pioneer spring and early summer ephemeral grasslands, dominated by non-nitrophilous therophytes. In Continental Portugal, these communities have not yet been fully investigated, and thus the objectives of the present study are: (1) to identify community types in therophytic grasslands; (2) to recognize those communities that configure the European priority habitat 6220* (pseudo-steppe with grasses and annuals); (3) to establish environmental gradients underlying their spatial variation; (4) to assess how floristic composition is affected by land use factors. Vegetation sampling using phytosociological methodology was carried out on 80 grasslands. Modified Twinspan classification and canonical correspondence analysis (CCA) was applied for the classification and ordination of relevés whereas partial CCA (pCCA) and variation partitioning were used to assess the relative influence of individual land use factors. Some 270 species were identified across 11 community types whose floristic patterns were mainly explained by environmental gradients related to altitude and soil type while land use variables could only explain a small part of the floristic variation. Based on biogeography and the determination of diagnostic species, four phytosociological new associations and a new subassociation are proposed: Holco-Brachypodietum distachyi, Holco-Micropyretum tenellae, Micropyro-Anthoxanthetum aristati and Leontodonto-Vulpietum bromoidis vulpietosum membranaceae. 相似文献
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Prof. Maria Cengia Sambo 《Plant biosystems》2013,147(3):551-562
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Prof. Eva Mameli-Calvino 《Plant biosystems》2013,147(1):255-258
Abstract The long pollen sequences from four volcanic lakes of the Lazio région are presented in order to outline the history of flora and vegetation on the Tyrrhenian side of Central Italy during the last hundred thousand years. The four long pollen records correlate satisfactorily with each other and reflect climatic changes at least at regional scale. Particular attention is paid to the development of arboreal vegetation during the last glacial. The local name “Lazio Complex” is given to the seven main fluctuations of trees of the Pleniglacial (from about 60,000 to about 30,000 years B.P.). The history of Zelkova, Abies, Picea, Fagus, Corylus, Ulmus, Carpinus betulus, Tilia in central Italy is outlined. 相似文献
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Dott. Felice Gioelli 《Plant biosystems》2013,147(3):638-642
Abstract Prioritization of endemic, threatened species and the habitats where they live is a crucial point of conservation actions, particularly in areas with rich endemic floras. In this study, we have developed a new procedure to define the conservation priorities among endemic plants and habitats by evaluating eight criteria. Five criteria deal with the geographic and ecological range of the evaluated species, whereas the other three refer to threats. After the evaluation of each criterion, we combined the partial scores to obtain a priority index (PI). Finally, we characterized the EU habitat categories of conservation concern on the basis of the average PI value of the plants living in each habitat. We tested the method on a list of 260 endemic plants from a biodiversity hotspot (Sardinia) that had an average PI of 3.66 ± 0.16. Even if the habitat categories that are most rich in endemic plants were rocky habitats, and coastal/halophytic habitats, the most endangered habitat was coastal sand dunes (PI = 6.75 ± 1.15). The method herein presented is complementary with the application of IUCN criteria. This integrated approach is a concrete solution that adapts IUCN criteria and categories to local contexts. 相似文献
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Prof. Silvia Zenari 《Plant biosystems》2013,147(3-4):252-266
Riassunto L'A. espone alcune osservazioni di critica sistematica riguardanti talune specie di Campanulacee delle Alpi Cadorine, di cui si è già occupata, secondo altri criteri, durante lo studio della vegetazione del Comelico (Alto Cadore). 相似文献
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Dott Valerio Giacomini 《Plant biosystems》2013,147(1):158-163
Summarium Hepaticas, quae in Herbario A. G. GASPARRINI Horti Botanici Ticinesis servantur, A. revisit. Species et varietates nonullas in Italia Meridionali hucusque non cognitas (et potissimum: Scapania subalpina, Riccia bifurca, R. ligula, R. ciliata var. intumescens, Pleuroschisma tricrenatum var. microphyllum) invenit. De duabus Ricciae speciebus, quibus GASPARRINI “trichophyllae” et “aeruginosae” nomina tribuerat, commentatus est. 相似文献
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Dott Francesco D'Amato 《Plant biosystems》2013,147(1-2):79-99
Riassunto L'A. stabilisce che in Plumbago europaca L. e Ceratostigma plumbaginoides Bunge lo sviluppo del gametofito femminile avviene secondo lo schema del tipo Plumbago tetramegasporiale 8-nucleato. Non uno stadio aberrante è stato osservato nè per l'una nè per l'altra specie. Viene messo in rilievo il carattere generale di singolare accelerazione dello sviluppo che, allo stato attuale delle conoscenze, rivestono i fatti embriologici finora noti nella sottofamiglia delle Plumbagincae nei riguardi di quelli stabiliti per la sottofamiglia delle Staticeae. 相似文献
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