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Bryophyte dynamics after fire in the Mediterranean macchia of Southern Italy was studied both by diachronic and synchronic approaches. Changes of bryophyte cover and species composition were found in relation to both age and fire intensity. During the first 2 yr after fire, bryophytes dominated the plots which had experienced the highest fire intensity while herbs were dominant in plots affected by lighter fires. Pioneer species, such as Funaria hygrometrica, Barbula convoluta and Bryum dunense, characterized recent intense fires, whereas Bryum torquescens, B. radiculosum and B. ruderale were dominant after less intense burning. Pleurochaete squarrosa, Tortula ruraliformis and Tortella flavovirens dominated intermediate successional stages. Pleurocarpous mosses were dominant only in the older closed stands. Different patterns of regeneration strategies were described: spores dominated early stages of intense fire, while vegetative propagules characterized later successional stages and less severely burned areas. Although bryophytes usually have a low abundance in Mediterranean vegetation, their role in post-fire vegetation dynamics may be locally enhanced according to burning conditions. Bryophyte dynamics after fire in the Mediterranean macchia of Southern Italy was studied both by diachronic and synchronic approaches. Changes of bryophyte cover and species composition were found in relation to both age and fire intensity. During the first 2 yr after fire, bryophytes dominated the plots which had experienced the highest fire intensity while herbs were dominant in plots affected by Lighter fires. Pioneer species, such as Funaria hygrometrica, Barbula convoluta and Bryum dunense, characterized recent intense fires, whereas Bryum torquescens, B. radiculosum and B. ruderale were dominant after less intense burning. Pleurochaete squarrosa, Tortula ruraliformis and Tortella flavovirens dominated intermediate successional stages. Pleurocarpous mosses were dominant only in the older closed stands. Different patterns of regeneration strategies were described: spores dominated early stages of intense fire, while vegetative propagules characterized later successional stages and less severely burned areas. Although bryophytes usually have a low abundance in Mediterranean vegetation, their role in post-fire vegetation dynamics may be locally enhanced according to burning conditions.

Sideritis italica (Miller) Greuter et Burdet is a widespread Mediterranean Lamiacea. Essential oils from S. italica flowerheads and leaves were extracted by hydrodistillation and then tested for their potential allelopathic activity against Raphanus sativus L. (Magnoliophyta) and the moss Tortula muralis (Hedw.) (Bryophyta), two organisms already tested for allelopathy, and against two bryophytes growing in the same environment as S. italica: the moss Bryum capillare Hedw. and the liverwort Lunularia cruciata (L.) Dum. For R. sativus, we considered seed germination and root and epicotyl growth. For the mosses, we used spore germination and protonemata development, while for the liverwort, we studied thallus and rhizoid growth as well as gemma development. Leaf oil was more active than flowerhead oil. The leaf essential oil caused a decrease in the percentage of seed germination and inhibition of root and epicotyl growth in R. sativus. Furthermore, it caused a strong inhibition of spore germination and protonemal development in both the mosses T. muralis and B. capillare and caused inhibition of gemma development and browning and inhibition of apical growth in the thallus of L. cruciata

In this paper different water-holding and transport adaptations to face the uneven and intermittent distribution of water in the ectohydric moss Tortula ruralis are referred to.The external conduction of water is operated by different and efficient systems (spaces between adjacent shoots, between leaves, leaves and stems, leaves and rhizoids, life form, etc.) which facilitate absorption and transport of solutions.Also epi-organ capillary systems (bases and revoluted margin of leaves, a groove, a close network of capillary channels determined by the papillae), intra-organ capillary systems (hyalocysts) and certain amount of internal conduction (conducting parenchyma, stereo- ma) co-operante to absorb and distribute water to the whole gametophyte.In addition, some adaptations to xerophytism and heliophytism (life form, disposition of phylloids, hair-points) are discussed. © Taylor & Francis Group, LLC.

In this study, a biomonitoring project using the moss Scorpiurum circinatum was carried out to evaluate the deposition and biological effects of heavy metals in the area of Acerra (Naples, S Italy), one of the vertices of the sadly called ‘‘Italian triangle of death’’ owing to the dramatic increase in tumours. The results clearly indicated that the study area is heavily polluted by heavy metals, a large proportion of which is likely present in the atmosphere in particulate form. The ultrastructural organization of exposed samples was essentially preserved, but cell membrane pits, cytoplasm vesicles and concentric multilamellar/ multivesicular bodies, probably induced by pollution, were found, which may be involved in the tolerance mechanisms to metal pollution in this moss species. Although severe biological effects were not found at the ultrastructural level in the exposed moss, effects on humans, especially after long-term exposure, are to be expected

This paper presents the results of a bioaccumulation study of trace elements in the Naples urban area based on the use of the moss Sphagnum capillifolium (Ehrh.) Hedw. and the lichen Pseudevernia furfuracea (L.) Zopf exposed in bags in 23 sites. Moss and lichen bags were exposed for 4 months starting from the beginning of July 1999. Bags gathering was carried out after 10 weeks of exposure, at the end of the dry season, and after 17 weeks, during the wet season. The elements Al, As, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Mo, Ni, Pb, Ti, V and Zn were analysed by inductively coupled plasma-mass spectrometry ICP-MS in both biomonitors. For the majority of the elements the total amounts found in S. capillifolium were higher than in P. furfuracea whether considering the whole period of exposure or the weekly uptake. It was observed that there was a much greater difference in metal accumulation by P. furfuracea between the dry and wet seasons compared with S. capillifolium. In the wet period, the lichen seems to accumulate a larger quantity of metals. With the exception of Mn, trace element concentrations did not appear to be significantly affected by the washing away of rainfall. K loss during exposure suggested cell membrane damage in both organisms. For P. furfuracea the K leakage was limited to the dry period of exposure. A clear distinction between "lithophilic" and "anthropogenic" elements was achieved by cluster analysis. Significant correlations were found among Fe-Cu-Cr-Ni, Pb-Cd-Co, V-Cr-Ni, Zn-Ni-Pb, suggesting a common source for each group of elements.

Accumulation of lead and zinc was studied in the moss Funaria hygrometrica Hedw. collected from mine tailings. Heavy metal accumulation in gametophytes and sporophytes was quantified by graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Pb and Zn accumulation in the placental zone was analysed by x-ray scanning electron microscopy (SEM) and transmission electron microscopy (TEM) microanalysis. Spectrometry showed that while moss gametophytes accumulated considerable concentrations of heavy metals, sporophytes accumulated only small concentrations of metals. X-ray SEM and TEM showed that the two metals accumulated in placental transfer cells on both the gametophytic and sporophytic sides. To investigate the uptake pattern for both metals under controlled conditions, F. hygrometrica plants collected from a non-polluted site were treated in the laboratory with separate solutions of Pb and Zn at two concentrations (10−2and 10−4 M ) for 24 or 168 h. Metal accumulation was analysed separately in gametophytes and sporophytes using GFAAS and ICP–AES. Each generation had a different accumulation quotient for both metals, and gametophytes accumulated significantly more metal than sporophytes. Concentrations of Zn in sporophytes were always higher than concentrations of Pb. The findings are discussed in relation to the role performed by the gametophyte and the placenta in the accumulation and sequestration of Pb and Zn.

The antibacterial activity of extracts from various parts of plants (leaves, fruits and stems) was studied in Actinidia chinensis, Feijoa sellowiana and Aberia caffra. These are tropical plants used for food. The fruits (subdivided into skin, pulp and seeds), leaves and stems were separately extracted and tested, in triplicate, against eight Gram positive and Gram negative bacterial strains. All the extracts, except from the leaves of A. caffra, showed activity against all the strains employed. Inhibition of bacterial growth was tested against Na-cefotaxime, benzyl penicillin and tetracycline. The antibiotic activity of fruit resides essentially in the seeds. The antibacterial activity of extracts from vegetative plant parts was generally less active that from fruit extracts. The minimum inhibiting concentration (MIC) and minimum bactericidal concentration (MBC) were determined for all the extracts and showed exclusively bacteriostatic activity.

funaria hygrometrica gametophytes were grown in in vitro controlled systems in the presence and absence of lead. Their nuclear genomes were then analyzed directly in situ with A+T and G+C specific fluorochromes, image analysis and statistical data elaboration by specific software, in order to characterize the different fractions of repetitive DNA. The results reveal qualitative and quantitative differences between the nuclear genomes of lead-stressed and unstressed individuals. These differences seem to consist of a significant increase in G+C rich repetitive DNA sequences in nuclei of the stressed individuals. These sequences form well defined agglomerates, generally situated adjacent to the nucleolar region, which increase in both size and number in the presence of lead. Some hypotheses are discussed.

We studied the antioxidant activity of the moss Leptodictyum riparium stressed with lead, cadmium, heat shock, and salinity. The acetonic extracts of the moss were tested for antioxidant activity on human whole blood leukocytes by a chemiluminescence (CL) assay. Stresses induced a significant increase of CL inhibition. Among the different stresses, heavy metals were the strongest enhancers of antioxidant activity. The different stresses induced antioxidant activity according the following scale: Cd > Pb > salinity > heat shock.

Trace element accumulation in the lichen Pseudevernia furfuracea (L.) Zopf was studied in the district of Acerra (province of Naples, southern Italy), one of the points forming Italy's Triangle of Death. P. furfuracea thalli, collected from Mt. Faito (province of Naples), were transplanted and exposed in bags at different sites in Acerra district, classified into three different site types (urban, rural and industrial). We aimed to test the hypothesis that P. furfuracea, when transplanted in the district of Acerra, would respond to air pollution accumulating trace elements and that element concentrations in the exposed lichens were different in relation to the three different environments, characterised by different pollution sources. Samples were exposed for six months, periodically collected and examined by ICP MS spectrometer assays to measure concentrations of 10 trace elements (Al, As, Cd, Cr, Cu, Fe, Mn, Pb, V and Zn). The exposed samples showed increases in concentrations of all the examined elements; the trace element concentrations were evaluated by calculating exposed to control (EC) ratios, for each site and each trace element, to better understand the accumulation rates. EC ratios were evaluated after 3 and 6 month exposures, at the end of spring and summer respectively: 6 month EC values were the highest. The urban sites showed EC ratios generally higher than industrial and rural; the most accumulated elements were Pb and Cu (at the urban sites), Cu and Zn (at the industrial sites), and Cu and As (at the rural sites). The chemical data were then processed using a multivariate approach (ordination, PCA) to better understand environmental gradients. Bioaccumulation data and PCA analysis showed the sampling sites separated by different trace element abundance. Trace element abundance patterns in the three site types are discussed in relation to the land use and the pollution sources. © 2008 Elsevier B.V. All rights reserved.

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses. © 2003 Elsevier Science Ltd. All rights reserved.

The present study was designed to evaluate the antibacterial and antioxidant activities of an aqueous extract from the tropical Feijoa sellowiana Berg. fruit which is widely used for human food. The extract was tested against gram-positive and gram-negative bacteria by a broth dilution test and on human whole blood leukocytes, as well as isolated neutrophils using a chemiluminescence (CL) assay. The extract inhibited bacterial growth; Pseudomonas aeruginosa, Enterobacter aerogenes and Enterobacter cloacae were the most sensitive. The fruit extract significantly decreased CL emission from human whole blood phagocytes and isolated polymorphonuclear leukocytes whether they were activated or not by soluble or phagocytic stimuli. F. sellowiana showed both antibacterial and antioxidant properties and therefore its extract might be used as a new multifaceted drug.

Protonemata of Funaria hygrometrica grown in artificial media containing different lead concentrations grow more slowly than controls and show a disturbance of polar growth, changed arrangement of chloroplasts, alterations of nucleus and septa position. Morphological effects are dose-dependent. At the lowest lead concentration (10-6 M), only a delay in development was observed, but no cellular alterations, At 10-5 M Pb nuclear migration, cellular shape, size and position of plastids, were altered and a variety of aberrant forms were present. At 10-4 M, besides these alterations, a drastic reduction of the protonemal system, high vacuolation and the growth of protonemal filaments from leaves were evident. The highest concentration, (10-3 M), caused death. Patterns of protonemal development and cellular arrangement in lead-treated samples showed similarities as well as differences, if compared to alterations induced by colchicine. Indirect immunofluorescence demonstrated a correlation between lead concentration and alteration of cytoskeletal organization (alterations similar to those induced by colchicine). Hypotheses are raised to account for effects of lead on microtubule structure, arrangement and cytoplasm organization.

Optical and SEM observation on the thallus of Lunularia cruciata show the presence of a hyaline parenchyma consisting of polyedric, slightly elongated cells with secondary wall thickenings mostly parallel. After removal of cytoplasmic content by mean of Triton-X-100, SEM observations show that the walls of the reticulate cells constituting the hyaline parenchyma have, between wall thickenings, large primary pit fields with numerous plasmodesmata derived pores on the unthickened areas of the walls. By contrast, the parenchymatous cells constituting the nerve have plasmodesmata derived pores grouped in small sparse fields, especially on the transverse of oblique walls. The authors suggest that the reticulate cells play a role in water holding capacity and lateral distribution, by symplastic and apoplastic conduction, of solutions carried by the midrib. A possible uniform pattern for water transport and distribution in all Marchantiales showing a similar histological organization of thallus is also ...