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11.
Foronda P Santana-Morales MA Orós J Abreu-Acosta N Ortega-Rivas A Lorenzo-Morales J Valladares B 《Experimental parasitology》2007,116(4):361-365
Intestinal helminths and blood protozoa are common parasites of lizards. In captivity they can be a serious problem, but no information on treatments is available. In this study, several antiparasitic drugs were studied in Gallotia caesaris (Lacertida) from La Gomera, the Canary Islands, Spain. A lack of efficacy of chloroquine, and a decrease in haemogregarine (Apicomplexa) infection by atovaquone-proguanil was demonstrated. Furthermore, a positive effect of fenbendazole against intestinal nematode infection was observed. In the Canary Islands, Gallotia bravoana and Gallotia simonyi (Lacertida) are included in a captive breading recovery plan. The present results are useful in order to keep these animals in good condition and to control their parasites. Moreover, these results are important for reptiles kept as pets, due to the previous lack of knowledge of parasite management. 相似文献
12.
Foronda P Valladares B Rivera-Medina JA Figueruelo E Abreu N Casanova JC 《Parasite (Paris, France)》2004,11(3):311-316
The prevalence and intensity of the parasites from 50 wild doves (Columba livia) from the city of Santa Cruz de Tenerife, in the island of Tenerife (Canary Archipelago), were studied. The following ectoparasites were found in apparently healthy pigeons (prevalences are shown in percentage (%) and mean intensities with their standard deviations): the acari Dermanyssus gallinae (De Geer, 1778) (6, 241.0 +/- 138.9) and Tinaminyssus melloi Fain, 1962 (10%, 218.3 +/- 117.3); the louses, Columbicola columbae Linnaeus, 1758 (100%, 111.4 +/- 76.8) and Campanulotes bidentatus Scopoli, 1763 (94%, 48.4 +/- 26.6); and the pigeon fly, Pseudolynchia canariensis Macquart, 1839 (36%, 6.2 +/- 1.6). The endoparasites we found were: a haemoprotozoan species, Haemoproteus columbae Kruze, 1890 (82%, 14.8 +/- 10.3 per 1000); coccidian oocysts, Eimeria sp. (50%, 0.2 x 10(3) +/- 1.7 x 10(3) per gr); a cestode species Raillietina micracantha (Fuhrmann, 1909) López Neyra, 1947 (44%, 12.3 +/- 9.4); and four nematode species, Tetrameres (Tetrameres) fissispina (Diesing, 1861) Travassos, 1915 (4%, 99.5 +/- 34.1), Synhimantus (Dispharynx) spiralis (Molin, 1858) (8%, 46.8 +/- 11.6), Ascaridia columbae (Gmelin, 1790) Travassos, 1913 (40%, 8.4 +/- 8.8) and Aonchotheca sp. (18%, 6.0 +/- 3.1). Several species detected in our study can be pathogens for C. bollii and C. junoniae, which are endemic pigeons of the Canary Islands, considered endangered species. Parasites (ectoparasites, protozoa and helminths) of C. livia found in Tenerife and others from wild and farm birds in the island were considered as healthy controls. 相似文献
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14.
Potent limonoid insect antifeedant from Melia azedarach 总被引:1,自引:0,他引:1
Carpinella C Ferrayoli C Valladares G Defago M Palacios S 《Bioscience, biotechnology, and biochemistry》2002,66(8):1731-1736
Systematic fractionation of a fruit extract from Argentine Melia azedarach L., which was monitored by an insect antifeedant bioassay, led to the isolation of meliartenin, a limonoid antifeedant, which existed as a mixture of two interchangeable isomers. At 4 microg/cm2 and 1 microg/cm2, the isomeric mixture was as active as azadirachtin in strongly inhibiting the larval feeding of Epilachna paenulata Germ. (Coleoptera: Coccinellidae) and the polyphagous pest, Spodoptera eridania (Lepidoptera: Noctuidae), respectively. 相似文献
15.
To understand the role of leaf-level plasticity and variability in species invasiveness, foliar characteristics were studied in relation to seasonal average integrated quantum flux density (Qint) in the understorey evergreen species Rhododendron ponticum and Ilex aquifolium at two sites. A native relict population of R. ponticum was sampled in southern Spain (Mediterranean climate), while an invasive alien population was investigated in Belgium (temperate maritime climate). Ilex aquifolium was native at both sites. Both species exhibited a significant plastic response to Qint in leaf dry mass per unit area, thickness, photosynthetic potentials, and chlorophyll contents at the two sites. However, R. ponticum exhibited a higher photosynthetic nitrogen use efficiency and larger investment of nitrogen in chlorophyll than I. aquifolium. Since leaf nitrogen (N) contents per unit dry mass were lower in R. ponticum, this species formed a larger foliar area with equal photosynthetic potential and light-harvesting efficiency compared with I. aquifolium. The foliage of R. ponticum was mechanically more resistant with larger density in the Belgian site than in the Spanish site. Mean leaf-level phenotypic plasticity was larger in the Belgian population of R. ponticum than in the Spanish population of this species and the two populations of I. aquifolium. We suggest that large fractional investments of foliar N in photosynthetic function coupled with a relatively large mean, leaf-level phenotypic plasticity may provide the primary explanation for the invasive nature and superior performance of R. ponticum at the Belgian site. With alleviation of water limitations from Mediterranean to temperate maritime climates, the invasiveness of R. ponticum may also be enhanced by the increased foliage mechanical resistance observed in the alien populations. 相似文献
16.
Carmelo E Pérez JA Zurita AI Piñero J de Armas F del Castillo A Valladares B 《The Journal of parasitology》2000,86(4):844-846
In this paper, we report a method for isolation of high molecular weight DNA from Leishmania promastigotes. This technique is especially indicated for small-scale purification of DNA suitable for the construction of highly representative genomic libraries. In our protocol, lysis buffer is compatible with RNase treatment, avoiding an additional precipitation step and consequent shearing of DNA. In order to prove the quality of the DNA isolated by this method, a Leishmania braziliensis genomic library was constructed, and an L. braziliensis KMP-11 gene was cloned after screening the library with a heterologous probe. 相似文献
17.
O. Godoy P. Castro-Díez F. Valladares & M. Costa-Tenorio 《Plant biology (Stuttgart, Germany)》2009,11(6):803-811
Flowering phenology is an important and poorly understood plant trait that may possibly be related to the invasiveness potential of alien species. The present work evaluates whether flowering time of invasive alien species is a key trait to overcome the climatic filters operating in continental Mediterranean ecosystems of Spain (characterised by summer drought and low temperatures in winter). We conducted comparisons between the flowering phenology of the invasive species in their native range and in Spain, and between flowering phenology of 91 coexisting invasive–native species pairs. For the alien species, geographical change from the native to the invaded region did not result in shifts in the start and the length of the flowering period. Overall, climatic conditions in the native range of species selected for a flowering pattern is maintained after translocation of the species to another region. Flowering of tropical and temperate invasive alien species peaked in summer, which contrasts with the spring flowering of native and invasive alien species of Mediterranean climate origin. By exploiting this new temporal niche, these invasive alien species native to tropical and temperate regions benefit from reduced competition with natives for abiotic and biotic resources. We suggest that human-mediated actions have reduced the strength of the summer drought filter in particular microhabitats, permitting the invasion of many summer-flowering aliens. 相似文献
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19.
Unventilated treeshelters have been widely used to protect seedlings against animal browsing and prevent seed predation by rodents, when the method used is seeding instead of planting. This last method has been a common practice in reforestation with oak species in Spain, because it prevents acorn predation. Although unventilated treeshelters have been widely used in this country, the performance of such devices under Mediterranean climatic conditions is a matter that deserves further investigations. To find out if treeshelters also provide protection against abiotic stress and improve the potential carbon gain in sheltered seedlings, we carried out a light and thermal characterization of the atmosphere inside the treeshelter. Moreover, we assessed the impact of treeshelters on light capture parameters, transpiration and photosynthesis using a Y-Plant model with Quercus faginea seedlings. Simulations with Y-Plant have shown that the growth in sheltered seedlings was mainly in spring and was limited by the low light levels. On other hand, in summer, the low values of potential carbon gain and water use efficiency in the sheltered seedlings could limit the seedling establishment. The main limiting factor during this season was the high temperatures. Therefore, the choice of the suitable treeshelter in this region must be carefully evaluated. The treeshelter must warranty high light levels and an optimal air renovation. Photoinhibition risks in leaves of sheltered and control seedlings have not been previously shown. 相似文献
20.
Fernando T. Maestre José L. Quero Fernando Valladares James F. Reynolds 《Plant and Soil》2007,296(1-2):53-64
We conducted an experiment to evaluate the plastic phenotypic responses of individuals, growing under intra-specific competition,
and populations of three co-occurring grassland species (Lolium
perenne, Plantago lanceolata, and Holcus lanatus) to joint variations in atmospheric CO2 partial pressure (P
CO2; 37.5 vs. 70 Pa), nutrient availability (NA; 40 vs. 120 mg N added as organic material), and the spatial pattern of nutrient supply (SH; homogeneous vs. heterogeneous nutrient supply). At both the population and individual levels, the aboveground biomass of the three species
significantly increased when the nutrients were heterogeneously supplied. Significant two- (SH × NA) and three-term (P
CO2 × NA × SH) interactions determined the response of traits measured on populations (aboveground biomass and below: aboveground
biomass ratio, BAR) and individuals (aboveground biomass and specific leaf area). The combination of a high SH and NA elicited
the highest plasticity of aboveground biomass in populations and individuals of the three species evaluated, and of BAR in
Holcus. Soil heterogeneity and elevated P
CO2 elicited the highest plasticity in the SLA of Plantago and Lolium individuals. Our results show that populations, and not only individuals, respond to soil heterogeneity in a plastic way,
and that plastic responses to elevated P
CO2 are complex since they vary across traits and species, and are influenced by the availability of nutrients and by their spatial
distribution. They also emphasize the importance of soil heterogeneity as a modulator of plant responses to global change
drivers.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Responsible Editor: Angela Hodge 相似文献