Search results for "Systematics"

Fungal Assemblages Associated with Roots of Halophytic and Non-halophytic Plant Species Vary Differentially Along a Salinity Gradient

2012

Structure of fungal communities is known to be influenced by host plants and environmental conditions. However, in most cases, the dynamics of these variation patterns are poorly understood. In this work, we compared richness, diversity, and composition between assemblages of endophytic and rhizospheric fungi associated to roots of two plants with different lifestyles: the halophyte Inula crithmoides and the non-halophyte I. viscosa (syn. Dittrichia viscosa L.), along a spatially short salinity gradient. Roots and rhizospheric soil from these plants were collected at three points between a salt marsh and a sand dune, and fungi were isolated and characterized by ITS rDNA sequencing. Isolates…

Clonal differences in growth and phenolics of willows exposed to elevated ultraviolet-B radiation

2003

Abstract In this study, the effects of elevated ultraviolet-B (UV-B, 280–320 nm) radiation on growth and leaf phenolics were evaluated in clones of dark-leaved willow ( Salix myrsinifolia Salisb.) and tea-leaved willow ( Salix phylicifolia L.). Willows were raised for one growing season in an irradiation field, where they were exposed either to a constant 50% increase in UV-B CIE radiation simulating 20–25% ozone depletion or to a small increase in UV-A radiation (320–400 nm). Control willows were grown in the irradiation field under solar radiation (ambient control). Despite the high constitutive concentrations of a UV-absorbing leaf flavonoid, dihydromyricetin, UV-treatments clearly reduc…

Kali dodecanesicum (Chenopodiaceae, Salsoloideae) a new species from Greece

2015

Kali dodecanesicum, a new species from some islands (i.e. Rhodes, Kos and Nisyros) of the Dodecanese in the south-eastern Aegean (Greece), is described and illustrated. According to recent literature, Kali is treated as a distinct genus from the polyphyletic Salsola s.l., which includes several annual species. The new species is morphologically well separated from the other Kali taxa mainly for the shape of the fruiting perianth, showing closer relationships with Kali ponticum. Its ecological requirements, distribution, and conservation status are also examined, together with an analytic key of the Kali species occurring in the Mediterranean area.

A new species of Kali (Salsoloideae, Chenopodiaceae) from Sicily, supported by molecular analysis

2015

Nomenclatural and taxonomical considerations on Kali , a controversial genus recently segregated from the polyphyletic Salsola s. lat. ( Chenopodiaceae ), are provided. The Kali group includes annual plants with leaves ending in a spine and lacking hypodermis, having also a cortex alternate to longitudinal chlorenchymatous striae. The species belonging to this genus mainly have a paleotemperate distribution (Europe, Asia and North Africa), occurring as aliens in North America, Australia and South Africa. A new species collected on Mt. Etna (Sicily), and closely related to K. australe , is described and illustrated as K. basalticum Its morphological and molecular features, karyology (2n=54),…

Revision of Sarcocornia (Chenopodiaceae) in South Africa, Namibia and Mozambique

2010

Abstract Sarcocornia comprises ca. 20–24 perennial, halophytic herb and shrub species. The genus is distinct from other genera in the Salicornioideae in having flowers that are more or less equal in size, arranged in a row, and with seeds that have a membranous hairy testa and lack perisperm. Sarcocornia is distributed worldwide, mainly in regions characterized by warm-temperate and, to a lesser extent, subtropical climates. The representatives of this genus are found in habitats such as estuarine salt marshes, tidal mud flats, coastal cliffs, inland salt pans, and salt-laden alluvia of intermittent semi-desert and desert streams. Some South African taxa also occur in inland (semi-desert) q…

Estimating the chance of success of archaeometric analyses of bone: UV-induced bone fluorescence compared to histological screening

2011

Abstract For most archaeometric analyses on archaeological bone material, such as the determination of the isotopic composition or genetic approaches, an advanced degree of diagenetic alteration can make designated analysis impossible. Since the lack of a positive signal is mostly seen only after time consuming and cost intensive sample processing, the need for an easy-to-apply screening method that allows a pre-selection of samples containing well-preserved biomolecules is obvious. In this study, we visually determined the UV-induced autofluorescence of 76 horse bone cross-sections, all from prehistoric archaeological sites of varying environmental and chronological background. In order to…

Mate Sampling and Assessment Procedures in Female Pied Flycatchers (Ficedula hypoleuca)

2010

Models of mate sampling strategies predict that choosiness should decrease throughout the breeding season due to increasing costs of delaying mating. Therefore, individuals who start searching mates relatively late, should spend less time on sampling, and sample fewer candidates compared to early individuals. We observed mate searching behavior of female pied flycatchers (Ficedula hypoleuca) by radio-tracking in study areas with 6–12 unpaired males. Contrary to the prediction, the observed numbers of males sampled by the searching females increased with time, i.e. late arriving females visited more males than early arrivers. However, this seems to be due to more active sampling of males in …

Seed germination in Sarcopoterium spinosum (L.) Spach from South-Eastern Sicily

2012

Sarcopoterium spinosum (L.) Spach is a nanophanerophyte whose presence in Sicily is limited to the South-East of the island. A study on seed germination behaviour of seeds collected from some populations indicates low viability of seedlings which could seriously put the long-term survival of these populations at risk.

A study on 3‐deoxy‐D‐arabino‐heptulosonic Acid 7‐Phospate Synthase in Higher Plants. The existence of three isoenzymes in Pisum sativum

1976

Significance of butterfly eyespots as an anti-predator device in ground-based and aerial attacks

2003

Many butterfly genera are characterised by the presence of marginal eyespots on their wings. One hypothesis to account for an occurrence of eyespots is that these wing pattern elements are partly the outcome of visual selection by predators. Bicyclus anynana (Satyrinae) has underside spotting on its wings but there is also a seasonal form in which the eyespots are reduced in size or totally absent. This natural variation gives us a useful tool to test the hypothesis that marginal eyespot patterns can decoy the attacking predator by, at least sometimes, diverting attack from vital body parts to the edges of the wings. We used lizards, Anolis carolinensis, and pied flycatchers, Ficedula hypol…