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691.
Alien species can represent a threat to several ecosystems because they can alter species relationships and ecosystem function. In Italy, Acacia saligna is a major invader and it forms dense stands in coastal environments. We analyze the impact of A. saligna in Italian Mediterranean dune systems. We randomly sampled coastal dune vegetation and investigated its floristic composition with ordination techniques. We compared species richness in invaded and non-invaded plots with rarefaction curves and analyzed the frequency of focal and ruderal species. A. saligna invaded Mediterranean scrub (habitats 2250* and 2260) and coastal Pinus dune wood (habitat 2270*) and it is particularly prevalent in sunny areas of habitat 2270*. We observed an increase in ruderal species and a decrease in focal species in the invaded plots of habitat 2270*. We suggest that more open and disturbed areas are more prone to A. saligna invasion. 相似文献
692.
A. Rodríguez A. Acosta C. Rodríguez 《World journal of microbiology & biotechnology》2014,30(9):2397-2406
Tomato greenhouses in the Canary Islands, Spain, were surveyed to estimate frequencies of resistance to benzimidazoles, dicarboximides, anilinopyrimidines and N-phenylcarbamates in Botrytis cinerea. Resistance to carbendazim, iprodione, pyrimethanil and diethofencarb was found in 74.2, 86.4, 28.8 and 31.8 % of isolates, respectively. Benzimidazole- and anilinopyrimide-resistant isolates were highly resistant, showing EC50 values above 500 µg/ml carbendazim and a mean EC50 value of 28.42 µg/ml pyrimethanil, respectively. By contrast, a low level of resistance was observed among dicarboximide-resistant isolates (mean EC50 value of 1.81 µg/ml iprodione). Phenotypes with double resistance to carbendazim and iprodione, and triple resistance to carbendazim, iprodione and pyrimethanil were the most common, occurring in 36.4 and 28.8 % of isolates. The surveyed greenhouses had never been treated with fenhexamid and Signum? (pre-packed mixture of boscalid and pyraclostrobin), and baseline sensitivities of B. cinerea isolates to these fungicides were determined. The EC50 values were within the range of 0.009–0.795 µg/ml fenhexamid and of 0.014–0.48 µg/ml Signum. In addition, available formulations based on elicitors of plant defense response and biocontrol agents were evaluated against B. cinerea in tomato plants under semi-controlled greenhouse conditions, the yeast Candida sake CPA-1 being able to reduce gray mold significantly when it was applied on petiole wounds and the plants were inoculated 24 h later. Likewise, C. sake was effective against B. cinerea in harvested tomato fruits, yeast-treated tomatoes showed a 70.66 and 30.31 % reduction in the diameters of decay lesions compared with controls after 10 days of storage at 20 and 9 °C, respectively. 相似文献
693.
Lupinus albus L. seeds were treated with different concentrations (from 10 μM to 50 mM) of H2O2, m-chloroperoxybenzoic acid
(mCPBA), ascorbate (ASC) and glutathione (GSH). The efficiency as inhibitors on germination and on the subsequent growth of
the hypocotyl was mCPBA > GSH > ASC = H2O2, which suggest that inhibitory efficiency was dependent on the compound per se
rather than on its redox nature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
694.
Bia D Pessana F Armentano R Pérez H Graf S Zócalo Y Saldías M Perez N Alvarez O Silva W Machin D Sueta P Ferrin S Acosta M Alvarez I 《Cell and tissue banking》2006,7(3):183-194
The viscoelastic and inertial properties of the arterial wall are responsible for the arterial functional role in the cardiovascular
system. Cryopreservation is widely used to preserve blood vessels for vascular reconstruction but it is controversially suspected
to affect the dynamic behaviour of these allografts. The aim of this work was to assess the cryopreservation's effects on
human arteries mechanical properties. Common carotid artery (CCA) segments harvested from donors were divided into two groups:
Fresh (n = 18), tested for 24–48 h after harvesting, and Cryopreserved (n = 18) for an average time of 30 days in gas-nitrogen phase, and finally defrosted. Each segment was tested in a circulation
mock, and its pressure and diameter were registered at similar pump frequency, pulse and mean pressure levels, including those
of normotensive and hipertensive conditions. A compliance transfer function (diameter/pressure) derived from a mathematical
adaptive modelling was designed for the on line assessment of the arterial wall dynamics and its frequency response. Assessment
of arterial wall dynamics was made by measuring its viscous (η), inertial (M) and elastic (E) properties, and creep and stress relaxation time constant (τC and τSR, respectively). The frequency response characterization allowed to evaluate the arterial wall filter or buffer function.
Results showed that non-significant differences exist between wall dynamics and buffer function of fresh and cryopreserved
segments of human CCA. In conclusion, our cryopreservation method maintains arterial wall functional properties, close to
their fresh values. 相似文献
695.
Palinurid lobsters are being exploited with increasing intensity in coral reef ecosystems, but marine protected areas may play a key role in preventing overfishing and local extinctions. In order to define the spatial requirements for protection, we compared the spatial and temporal patterns in distribution, density, biomass, size structure, and reproductive seasonality of Caribbean spiny lobsters Panulirus argus and the congeneric spotted lobsters P. guttatus on coral patch reef, forereef, and deep reef habitat at Glover's Reef, Belize. The relative impact of fishing on P. argus was also examined in an isolated marine reserve and adjacent fished habitats, in comparison with the relatively unfished distribution of P. guttatus. Over a 5-year period, both species co-occurred in all major reef habitats, but aspects of their population dynamics differed markedly due to both habitat and fishing effects. All size classes of spiny lobsters P. argus occupied shallow patch reefs, but large adults were predominant on the deep wall reef. Panulirus guttatus also occupied patch reefs in the lagoon, but spur-and-groove forereef appeared to be the primary habitat of this species. Density and exploitable (adult) biomass of P. argus increased significantly over time in the protected patch reef habitat of the lagoon but remained stable on deep reef habitat. The biomass of spotted lobsters P. guttatus in all habitats was at least an order of magnitude less than that of exploitable P. argus. Reproductive activity by both species was evident most of the year in all habitats, but breeding P. argus females were concentrated on the deep reef. Commercial fisheries for spotted lobsters P. guttatus are currently being considered for development, but data from this and other studies suggest that such a fishery may be relatively unproductive and may lead to rapid localized extinctions. Spiny lobsters P. argus used a variety of coral reef habitats, but spotted lobsters P. guttatus were habitat specialists restricted to shallow reef habitat. The protection needs of both species are similar in one aspect: large protected areas. However, P. argus required large areas with heterogeneous habitats including coral reefs and seagrass beds, whereas P. guttatus required large areas of coral reef habitat. 相似文献
696.
697.
Bráulio Fabiano Xavier de Moraes Rodrigo Furtado dos Santos Bruno Marco de Lima Aurélio Mendes Aguiar Alexandre Alves Missiaggia Donizete da Costa Dias Gabriel Dehon Peçanha Sampaio Rezende Flávia Maria Avelar Gonçalves Juan J. Acosta Matias Kirst Márcio F. R. ResendeJr Patricio R. Muñoz 《Molecular breeding : new strategies in plant improvement》2018,38(9):115
The successful application of genomic selection (GS) approaches is dependent on genetic makers derived from high-throughput and low-cost genotyping methods. Recent GS studies in trees have predominantly relied on SNP arrays as the source of genotyping, though this technology has a high entry cost. The recent development of alternative genotyping platforms, tailored to specific species and with low entry cost, has become possible due to advances in next-generation sequencing and genome complexity reduction methods such as sequence capture. However, the performance of these new platforms in GS models has not yet been evaluated, or compared to models developed from SNP arrays. Here, we evaluate the impact of these genotyping technologies on the development of GS prediction models for a Eucalyptus breeding population composed of 739 trees phenotyped for 13 wood quality and growth traits. Genotyping data obtained with both methods were compared for linkage disequilibrium, minor allele frequency, and missing data. Phenotypic prediction methods RR-BLUP and BayesB were employed, while predictive ability using cross validation was used to evaluate the performance of GS models derived from the different genotyping platforms. Differences in linkage disequilibrium patterns, minor allele frequency, missing data, and marker distribution were detected between sequence capture and SNP arrays. However, RR-BLUP and BayesB GS models resulted in similar predictive abilities. These results demonstrate that both genotyping methods are equivalent for genomic prediction of the traits evaluated. Sequence capture offers an alternative for species where SNP arrays are not available, or for when the initial development cost is too high. 相似文献
698.
Ecosystem respiration in a heterogeneous temperate peatland and its sensitivity to peat temperature and water table depth 总被引:1,自引:0,他引:1
Radosław Juszczak Elyn Humphreys Manuel Acosta Maria Michalak-Galczewska Dariusz Kayzer Janusz Olejnik 《Plant and Soil》2013,366(1-2):505-520
Background and aims
Ecosystem respiration (R eco ) is controlled by thermal and hydrologic regimes, but their relative importance in defining the CO2 emissions in peatlands seems to be site specific. The aim of the paper is to investigate the sensitivity of R eco to variations in temperature and water table depth (WTD) in a wet, geogenous temperate peatland with a wide variety of vegetation community groups.Methods
The CO2 fluxes were measured using chambers. Measurements were made at four microsites with different vegetation communities and peat moisture and temperature conditions every 3 to 4 weeks during the period 2008–2009, 2 years with contrasting WTD patterns. Models were used to examine the relative response of each microsite to variations in peat temperature and WTD and used to estimate annual total R eco .Results
Temporal variations in R eco were strongly related to peat temperature at the 5 cm depth. However, two of the microsites did not show any significant change in this relationship while two others showed contrasting responses including an increase and decrease in temperature sensitivity with deeper WTD. Average R eco varied among the microsites and tended to be greatest for those with greatest leaf area which also positively correlated with deeper WTD, ash content and degree of peat decomposition at 20 cm. A combined temperature and WTD model explained up to 94 % of the temporal variation in daily average R eco and was used to show that on an annual basis, R eco was between 5 and 18 % greater in the warmer year with deeper WTD.Conclusion
Microsite-specific responses were related to differences in vegetation and peat characteristics among microsites. R eco may have remained insensitive to WTD variations at one microsite due to the dominance of autotrophic respiration from abundant sedge biomass. At a Sphagnum-dominated microsite, a lack of response may have been due to relatively small variations in WTD that did not greatly influence microbial respiration or due to offsets between decreasing and increasing respiration rates in near-surface and deeper peat. The microsite with the most recalcitrant peat had reduced R eco sensitivity to temperature under more aerobic conditions while another microsite showed the opposite response, perhaps due to less nutrient availability during the wet year. Ultimately, micro-site specific models with both soil temperature and WTD as explanatory variables described temporal variations in R eco and highlighted the significant spatial variations in respiration rates that may occur within a single wetland. 相似文献699.
Giuseppe Fenu Marta Carboni Alicia T. R. Acosta Gianluigi Bacchetta 《Folia Geobotanica》2013,48(4):493-508
Coastal dune ecosystems show strongly dynamic interactions between abiotic and biotic factors. The relationship between plant communities and environmental factors has been previously studied in oceanic dune systems, but few studies have been conducted along Mediterranean coasts. In this study we analyze the relative contribution of environmental factors associated with two of the main drivers of vegetation zonation: soil and wind. We chose two representative coastal dune systems in the western Mediterranean Basin subject to low levels of human disturbance. Within 54 plots we recorded floristic and environmental data. Vegetation zonation and relationships with environmental variables were investigated through unconstrained and constrained ordinations, correlation, and variance partitioning. Environmental factors shift along the gradient from coastal to inland dunes, concomitantly with the pattern of community types from annual beach communities to shrub-covered fixed dunes. This general gradient is similar both in the Mediterranean and in the oceanic coastal ecosystems, with the same factors that show similar trends along the dune profile. However, our results highlight some peculiarities of the Mediterranean dune systems in relation to the amount of variation explained by environmental factors. While most studies conducted in oceanic ecosystems find that wind-related parameters may control the vegetation zonation, in our study areas we observed a minor importance of the wind-related variables when compared to soil properties. In particular, organic matter and grain-size variability were found to be closely correlated with the distribution of plant communities along the gradient. 相似文献
700.
G.K. Cury U. Matte O. Artigalás T. Alegra R.V. Velho F. Sperb M.G. Burin E.M. Ribeiro C.M. Lourenço C.A. Kim E.R. Valadares M.F. Galera A.X. Acosta I.V.D. Schwartz 《Gene》2013
Mucolipidosis II and III (MLII and MLIII) alpha/beta are rare autosomal recessive lysosomal storage diseases (LSDs) caused by pathogenic variations in the GNPTAB gene. GNPTAB gene codes for the α and β subunits of phosphotransferase, the enzyme responsible for synthesis of the mannose-6-phosphate (M6P) marker that directs lysosomal enzymes to the lysosome. 相似文献