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1.
The present work is aimed at studying several Asperula (Rubiaceae) sect. Cynanchicae populations in southern Apennines, Italy, with particular reference to those referred to A. calabra, by employing biometrical methods on macromorphological data. Among other historical misapplications, A. cynanchica subsp. cynanchica seems to be very rare or missing in southern Italy. The enigmatic Asperula calabra, confirmed to be limited to a single mountain population in Calabria, appears to be strictly related to A. aristata subsp. scabra, so we suggest to treat it as a further subspecies of A. aristata. This latter species is otherwise distributed throughout southern Italy with subsp. scabra and subsp. aristata, characterised by slight morphological differences, which are correlated to altitudinal ranges.  相似文献   

2.
Impatiens L. is taxonomically a complicated genus that necessitates fresh characterization to resolve its taxonomy. This study therefore aimed at ascertaining micro-morphological characters in the foliar epidermis of Impatiens. For this purpose, we gathered twelve taxa (10 species and 2 subspecies) mostly from the northern regions of Pakistan and studied qualitative and quantitative characters depicting variation in epidermal cells, stomata, and trichomes on both surfaces. Multicellular, uniseriate trichomes were observed only in I. balsamina L., and raphides in I. balfourii Hook. f. and I. thomsonii Hook. f. while stomata were exclusively anomocytic in all species. Morphological variation in the foliar epidermal characters and their diagnostic value has been depicted by constructing a taxonomic key to all taxa. The study revealed that although foliar epidermal characters in Impatiens did not desirably assort taxa on the basis of structural topographies, yet demonstrated adequate variation distinguishing the Pakistani taxa.  相似文献   

3.
4.
The genus Saussurea comprises many species with highly medicinal, religious or other economical values. The chromosome number in the genus ranges from 2n = 24 to 108, based on x = 12, 13, 16, or 17, but the primary base number is still not clear. The present meiotic study cover 8 species (14 populations) of Saussurea from the Northwest Himalayas, and add new or varied cytotypes, as an attempt to solve the enigmatic cytogenetic variations in the genus. The chromosome numbers in Saussurea auriculata (n = 16) is new to the world, while S. costus (n = 17), S. jacea (n = 17) and S. roylei (n = 17) reveal the varied cytotypes at world level. Besides, S. taraxicifolia (n = 16) is a first ever report for Indian populations. The meiotic studies on different populations reveal a substantial amount of meiotic abnormalities in the form of chromosome stickiness, un-oriented bivalents, cytomixis, laggards, etc. leading to the meiocytes with less (aneuploidy) or more (polyploidy) chromosome numbers. These abnormalities may produce unreduced pollen grains and adversely affect pollen viability. The high number of these meiotic abnormalities may be responsible for the chromosome number variation in the genus.  相似文献   

5.
Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.  相似文献   

6.
A new Centaurea L. (Asteraceae) species from Turkey is described and illustrated. Centaurea mersinensis Uysal and Hamzao?lu exists on calcareous slopes in Pinus brutia forests of Ayd?nc?k (Mersin) in southern Anatolia. It belongs to C. sect. Phalolepis (Cass.) DC., and taxonomically its closest relative is C. lycaonica. Diagnostic morphological characters from very similar taxa are provided, and a key is provided that includes related species of sect. Phalolepis from Turkey. The geographical distribution of the new species and relatives of the same section are mapped. The chromosome number of C. mersinensis, 2n = 18, counted in root tips, is also reported and illustrated.  相似文献   

7.
A new desmid genus, Actinodontum Alfinito et Coesel, is described from mountain areas of tropical Africa. The newly described genus differs from the allied genus Actinotaenium by the presence of marked teeth at the base of each semicell that alternate with those on the other semicell. Morphology of the type species, Actinodontum lomaense (Alfinito et Mazzoni) Alfinito et Coesel, is dealt with in much detail. Cosmarium basituberculoides Bourrelly et Couté and Cosmarium elgonense Kusel-Fetzmann are transferred to the new genus. The geographical distribution of the genus Actinodontum is discussed.  相似文献   

8.
Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5–8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. This study tests previously proposed models of diet and hunting behaviour of these extinct carnivorans. Relative grinding area (RGA) of lower molars and wear pattern on upper molars suggest that bear-dogs were carnivorous. Amphicyon and Ischyrocyon possessed skeletal features of both ambush (short distal limb segments) and pursuit (caudally bent olecranon process of ulna) living predators. Therefore, bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum.  相似文献   

9.
Total extracts and kuwanon G from Morus nigra root bark showed antifungal activity against several phytopathogenic fungi, with minimal inhibitory concentration (MIC50) ranging from 32 to 128 μg/ml and from 16 to 64 μg/ml, respectively. Acetonic extracts inhibited 60% B. cinerea biofilm formation at concentration of 128 μg/ml.  相似文献   

10.
Abstract

Semi-natural dry grasslands are habitats of high conservation concern. These ecosystems have not been extensively explored in the Tyrrhenian sector of the Italian peninsula, particularly in the Submediterranean climatic region. In order to address this issue and to define the synecology, syndynamics and syntaxonomy of calcareous grasslands in this area, we considered 127 phytosociological relevés. Our sampling was performed in the Lazio region according to a stratified sampling scheme based on homogeneous land units, defined by means of an ecological land classification process. We analyzed the vegetation data using multivariate methods. Two new associations, whose typical aspects occur in the mesotemperate phytoclimatic belt, were identified:Erysimo pseudorhaetici-Dasypyretum villosi (Taenianthero-Aegilopion) and Scorpiuro muricati-Brometum erecti (Phleo-Bromion). Phytoclimatic belts within the Submediterranean region cause a significant degree of differentiation within Scorpiuro-Brometum, which was described at the subassociation and variant levels. The overall relevance of therophytes represents the most important feature distinguishing Scorpiuro-Brometum from the published Bromus erectus associations. At a finer scale, the presence of the two physiognomically different grassland communities is related to different soil types. All these communities are dynamically linked to Quercus virgiliana and Q. pubescens woods, and contribute to the coenological differentiation of the vegetation series related to such woodlands.  相似文献   

11.
Morphological variation, ploidy level and genetic diversity have been studied on 10 populations of the Pilosella hoppeana aggr. from the Alps, Abruzzo, Calabria and Sicily. Chromosome counts showed that the plants from Abruzzo and those from Sicily are tetraploid (2n = 36); they are assigned to P. hoppeana subsp. macrantha. The plants from the Alps (P. hoppeana subsp. hoppeana) and those from Calabria are diploid. The Calabrian populations, previously included in P. hoppeana subsp. macrantha, are shown to belong to a separate species, P. leucopsilon. The principal component analysis, based on 25 morphological characters, allowed distinguishing clearly four groups. An allozyme study using 10 enzyme systems revealed 7 polymorphic loci with a total of 20 alleles, some of them exclusive at regional level, others shared between populations showing similar morphological features. The genetic differentiation between populations was relatively high. The obtained dendrogram supports recognition of the morphologically defined taxa.  相似文献   

12.
In the present study, the chemical composition of the essential oils from aerial parts of Centaurea grinensis Reuter (K) collected at ?uta Lova, near Senj (Croatia), and aerial parts (L1) and flowers (L2) of C. apiculata Ledeb. collected near Rebro village, near Breznik town, Znepole Region (Bulgaria), both belonging to subgenus Lopholoma (Cass.) Dobrocz, was evaluated by GC and GC-MS. The main components of K were 4-vinyl guaiacol (21.5%), hexadecanoic acid (16.2%), acetophenone (12.5%). Caryophyllene oxide (15.8%) together with sphathulenol (14.5%) and humulene epoxide II (9.4%) were recognized as the main constituent of both the aerial part (L1) and flowers (L2) of C. apiculata. Furthermore, a complete review on the composition of the essential oils of all the Centaurea taxa belonging to subgenus Lopholoma studied so far has been inserted and cluster analysis (PCA) was carried out.  相似文献   

13.
Abstract

The terrestrial orchid, Orchis pauciflora Ten., growing in poor grassland and garrigue of Central Mediterranean region, is local and rare and has been included in the red lists of several Italian regions. We investigated the diversity of fungal associates in O. pauciflora adult plants collected in two protected areas of Tuscany (Central Italy). Genomic DNA was extracted from mycorrhizal roots of 12 orchid plants and the fungal ITS were amplified and sequenced. Several fungal associates, belonging to different taxa of basidiomycetes (Tulasnellaceae) and ascomycetes such as Leptodontidium, Exophiala and Phialophora species, were recovered. The trophic role of these fungi and their impact on O. pauciflora growth and conservation are discussed.  相似文献   

14.
Constraining the origin of animal groups is allowed, to some extent, by discoveries of Cambrian Lagerstätten that preserve both mineralizing and nonmineralizing organisms. A new species is reported here of the Cambrian arthropod Skania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism Parvancorina and firmly establishes a Precambrian root for arthropods. A new monophyletic group, Parvancorinomorpha, is proposed as the first clade within the arthropod crown group demonstrably ranging across the Neoproterozoic–Paleozoic transition. The Parvancorinomorpha is interpreted to be the sister group of the Arachnomorpha. Incipient cephalization in Skania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods.  相似文献   

15.
Abstract

A two-year study has been conducted in an abandoned Pb/Zn mining site, with the aim of investigating the feasibility of phytoremediation using two native Mediterranean plants (Pistacia lentiscus and Scrophularia bicolor) and of assessing the performance of amendments able to reduce the toxic effects of heavy metals. The amendments used were compost, chemical fertilizer, and zeolites, used singly or in combination. Depending on the amendments applied, the two species showed different mortality rates in the different plots, but all produced an increase in P. lentiscus survival, while S. bicolor survival improved only when amended with zeolite or zeolite + fertilizer. Scrophularia bicolor proved to be a more efficient accumulator than P. lentiscus, especially for Pb uptake. Pistacia lentiscus accumulated metals mostly in the roots. The effect of amendments was to generally reduce the bioavailable metal fraction, especially lead, in the plots amended with compost. Pistacia lentiscus proved to be the most suitable species for phytostabilization and environmental restoration, both for its resistance to metals and high phytomass production. The experiments demonstrate that the use of compost not only encourages this kind of revegetation in degraded areas, but is also an economical option that uses a by-product of solid municipal waste treatment.  相似文献   

16.
Abstract

The genus Baldellia Parl. has always been a complex taxon. Three species and three subspecies have been proposed for the Iberian Peninsula. The morphological variation of this genus in the Iberian Peninsula, Balearic islands and northern Morocco, and its thermo-pluviometric and altitudinal correlation are the focus of this contribution. Twenty-eight morphological variables were examined and subjected to a multivariate statistical analysis. The three morphotypes observed (Form 1, which includes B. ranunculoides subsp. repens and B. alpestris; Form 2, which includes B. ranunculoides and Form 3 – for the new combination B. ranunculoides subsp. ranunculoides var. tangerina (Pau) J. Rocha, A. Crespí, M. García-Barriuso, R. Almeida, J. Honrado, comb. nova proposed here for the first time) seem to represent different reproductive strategies. Morphological variables related with the presence or absence of stolons and the architecture of the inflorescence; the size and number of fruits are the most discriminating variables. Form 1 represents the asexual morphotype; Forms 2 and 3 correspond to morphotypes for which sexual reproduction is preferential. The environmental approach revealed that the asexual form (Form 1) grows in temperate, in more humid conditions, and within a broad altitudinal range. In contrast, the two sexual forms are more common in warmer and drier conditions, and occur over a narrower interval of altitudes.  相似文献   

17.
A rust fungus attack was observed on Tree Spurge (Euphorbia dendroides) in two regions of southern Italy. Uredinia and telia of a Melampsora species were detected on the leaves, bracts of the cyathia and capsules of E. dendroides. On the basis of the morphological characteristics and rDNA ITS sequences of the above mentioned structures, the fungus was identified as M. gelmii. This report suggests that M. gelmii seems to be a specific taxon in the M. euphorbiae complex and to be more widespread than previously detected in Italy. Further investigations within the M. euphorbiae complex would be desirable in order to elucidate the identity of M. gelmii as a peculiar form of a still poorly explored species.  相似文献   

18.
This study is the first molecular and biochemical analysis conducted on Pompia, a plant of unknown origin that is endemic to Sardinia; this plant is thought to belong to the Citrus genus. Here, genes coding for the enzymes superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7), and polyphenol oxidase (PPO, EC 1.14.18.1) were identified. We detected the aforementioned enzymes in fresh leaf tissue and assessed the catalytic activity of each to support the molecular and biochemical data. This was the first molecular study to define the primary structure of proteins with antioxidant activity in Pompia. The study also contributed to the enrichment of gene databases and created the basis for molecular phylogenetic studies, which is important because this plant currently has no taxonomic or phylogenetic classification.  相似文献   

19.
This paper deals with the extraction, amplification and sequencing of ancient DNA (aDNA) from spikelets of wild cereals dated at ca. 9000 cal yr BP, representing the most ancient plants with preserved genetic material from the Sahara desert. The sub-fossil records were collected from the archaeological excavation carried out at Takarkori, an archaeological site located in south-western Libya. Morphological and genetic analyses were made on 100 well preserved dried spikelets. Ten DNA extraction protocols were performed to evaluate nucleic acid recovery in terms of DNA yield, purity and amplification success of the chloroplast barcode region matK. The extraction protocol that returned the most suitable DNA to be amplified is the Kistler and Shapiro (2011: J Archaeol Sci 38: 3549-3554) modified protocol. In our study, the results from matK amplification suggested that four specimens are the most appropriate number of spikelets for these analyses. DNA was then used for PCR amplifications of four chloroplast barcode genes: rbcL, matK, trnH-psbA and trnL. A phylogenetic analysis shows the strict relation between the archaeological specimens and modern Panicoideae, supporting the morphological identification. The results indicate that spikelets have a close relation to Panicum laetum Kunth, a wild cereal still collected in tropical Africa.  相似文献   

20.
Festuca s.l. is a crucial group of Crop Wild Relatives (CWR) genera, globally employed as fodder, lawn grasses and for habitat restoration. Lists elaborated strictly on the basis of a taxonomic approach are urgently needed to be used to find gaps in existing ex situ collections, to assess the conservation status of taxa of ascertained utility and include them in national Red Lists and to identify the most valuable taxa to be included in “preservation mixtures”, as per Commission Directive 2010/60/EU. As an example, the first taxonomically based priority list of Italian CWRs of Festuca s.l. is here provided.  相似文献   

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