Biologia

Although tree hollows seem to be key structures for a wide range of forest mammals, their importance for Mediterranean forest carnivores remain poorly understood. Here we address this issue, by analysing daily resting site use by 21 radio-collared common genets. Tree hollows were used far more frequently during the wet season (October–April; 73.1% of daily locations) than in the dry season (May–September; 47.6%).
Nests and underground dens were the second and third most frequently used resting sites, respectively, in both wet (17.5% and 9.4%) and dry (34.1% and 18.3%) seasons. Each individual reused a large percentage of its resting sites (65.7%). Some resting sites (17.3%) were used by more than one individual, but simultaneous sharing was exceedingly rare (0.56% of daily locations). Hollow use probability during the wet season varied little in relation to environmental variables, though there was a tendency to be higher away from riparian habitats (>50 m) and to be lower in sites with very high shrub cover (>80%). Environmental influences were responsible for more variability in the dry season, when hollow usage was highest in hot days, in days with precipitation, far from riparian habitats, close to sources of human disturbance, in landscapes dominated by continuous forest habitats, and in sites with low shrub cover. Results support the importance of tree hollows for Mediterranean forest carnivores, probably because they provide safe shelter against unfavourable weather, predators and human disturbance. However, results also revealed the importance of riparian trees, which offer support for building nests close to sources of water and food during the dry season. Considering home range size and the average number of hollow-bearing trees used by each genet, we recommend that management of cork and holm oak forests should strive to safeguard at least 4.6 hollow-bearing trees per 100 ha, while simultaneously maintaining large riparian trees. This will improve the resting habitat for common genets, while presumably favouring also other Mediterranean carnivores.

Fungi naturally present in olive trees were identified and tested for their antagonistic potential against Colletotrichum acutatum. A total of 14 isolates were identified, 12 belonged to genera Alternaria, Epicoccum, Fusarium, Aspergillus, Anthrinium, Chaetomium, Diaporthe, Nigrospora, one to family Xylariaceae and one was unclassified. All fungal isolates showed some inhibitory action over the growth of C. acutatum during dual culture growth, however, when agar-diffusible tests were performed only five fungal isolates caused C. acutatum growth inhibition: Alternaria sp. isolate 2 (26.8%), the fungus from Xylariaceae family (14.3%), Alternaria sp. isolate 1 (10.7%); Diaporthe sp. (10.7%), Nigrospora oryzae (3.5%). Volatile substances produced by these isolates were identified through gas-chromatography techniques, as phenylethyl alcohol, 4-methylquinazoline, benzothiazole, benzyl alcohol, lilial, galaxolide, among others. These inhibitory volatiles could play a significant role in reduction of C. acutatum expansion in olive and their study as potential biocontrol agents should be further explored.

Book Description: DNA vaccination is one of the most promising techniques for immunization against diseases caused by viruses, protozoa, bacteria, and even for tumors and illnesses with genetic origins. These vaccines can be administered by direct inoculation of plasmid by several routes. In this book, the authors present topical research in the study of the types, advantages and limitations of DNA vaccines. Topics discussed include the role of novel carrier constructs in effective and safe DNA vaccine delivery; improving the immunogenicity of DNA vaccines; the role of DNA-IL-12 vaccination in cosinphilic inflammation; genetic immunization enabling re-direction of the host immune system resulting in the development of effective immune responses; and DNA vaccination against herpesvirus.

O presente Relatório de Progresso I apresenta toda a informação referente à implementação e avaliação das acções no período de Janeiro a Agosto de 2011 da 2ªFase do projecto “Estudo e Valorização da Biodiversidade Componente da Fauna das Fábricas ...

O presente Relatório Final apresenta toda a informação referente à implementação e avaliação das acções e os resultados finais da monitorização da fauna no período de vigência da 2ªFase do projecto “Estudo e Valorizaçãoda Biodiversidade na Propriedade ...

Aims:  Our aim was to evaluate the effect of acid and alkaline pH on chickpea rhizobia, and on chickpea–rhizobia symbiosis.Methods and Results:  Forty-seven rhizobia isolates obtained from 12 Portuguese soils were grown at pH 5, 7 and 9. Among these, 26 grew more at pH 5 than at 7, suggesting the existence of acidophiles. All isolates were identified as mesorhizobia by 16S rDNA partial sequence analysis. Molecular phylogeny of isolates based on partial 16S rDNA sequences suggests that pH tolerance might be species related. Further studies were conducted with six isolates, which were able to grow at acid pH. Isolates PT-35 and 64b grow optimally at pH 6–5–7, with a minimal pH range from 5 to 3, and may thus be considered as moderately acidophilic. Both isolates belong to a previously identified putative new Mesorhizobium species, based on 16S rDNA sequence.Conclusions:  Two moderately acidophilic mesorhizobia isolated from chickpea were identified (PT-35 and 64b). A positive correlation was found between the symbiotic effectiveness at low pH and the acid tolerance of rhizobia isolates.Significance and Impact of the Study:  This is the first report on moderately acidophilic mesorhizobia, and is an important contribution for the development of highly effective inoculants for chickpea in acid soils.

Several Mesorhizobium species are able to induce effective nodules in chickpea, one of the most important legumes worldwide. Our aims were to examine the biogeography of chickpea rhizobia, to search for a predominant species, and to identify the most efficient microsymbiont, considering Portugal as a case study. One hundred and ten isolates were obtained from continental Portugal and Madeira Island. The 16S ribosomal RNA gene phylogeny revealed that isolates are highly diverse, grouping with most Mesorhizobium type strains, in four main clusters (A–D). Interestingly, only 33% of the isolates grouped with Mesorhizobium ciceri (cluster B) or Mesorhizobium mediterraneum (cluster D), the formerly described specific chickpea microsymbionts. Most isolates belong to cluster A, showing higher sequence similarity with Mesorhizobium huakuii and Mesorhizobium amorphae. The association found between the province of origin and species cluster of the isolates suggests biogeography patterns: most isolates from the north, center, and south belong to clusters B, A, and D, respectively. Most of the highly efficient isolates (symbiotic effectiveness >75%) belong to cluster B. A correlation was found between species cluster and origin soil pH of the isolates, suggesting that pH is a key environmental factor, which influences the species geographic distribution. To our knowledge, this is one of the few surveys on chickpea rhizobia and the first systematic assessment of indigenous rhizobia in Portugal.