Characterization of the structure,dynamics, and productivity of mixed-species stands: review and perspectives     

Miren del Río  Hans Pretzsch  Iciar Alberdi  Kamil Bielak  Felipe Bravo  Andreas Brunner  Sonia Condés  Mark J. Ducey  Teresa Fonseca  Nikolas von Lüpke  Maciej Pach  Sanja Peric  Thomas Perot  Zahera Souidi  Peter Spathelf  Hubert Sterba  Martina Tijardovic  Margarida Tomé  Patrick Vallet  Andrés Bravo-Oviedo 《European Journal of Forest Research》2016,135(1):23-49

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Responses of photosynthetic parameters to differences in winter temperatures throughout a temperature gradient in two evergreen tree species     

Sonia Mediavilla  Patricia González-Zurdo  Josefa Babiano  Alfonso Escudero 《European Journal of Forest Research》2016,135(5):871-883

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Methods for Cercospora coffeicola protoplast isolation and genetic transformation with the green fluorescent protein     

André Gomes Coelho Souza  Sonia Herrero  Luiz Antonio Maffia  Margaret Elizabeth Daub 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(2):235-238

Cercospora coffeicola is the causal agent of brown eye spot on coffee leaves. Although the disease has significant importance, few molecular studies have been done with C. coffeicola. Here we report a protocol for isolating protoplasts as well as development of a genetic transformation system using Green Fluorescent Protein. High yields of protoplasts (≈10⁸/ml) were obtained from mycelial cultures from five isolates of C. coffeicola. One isolate was transformed with a vector encoding hygromycin resistance and Green Fluorescent Protein. Out of 43 hygromycin-resistant transformants obtained, Green Fluorescent Protein was highly expressed in one (2.3 %).  相似文献   

Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO₂     

Eva van Gorsel  Nicolas Delpierre  Ray Leuning  Andy Black  J. William Munger  Steven Wofsy  Marc Aubinet  Christian Feigenwinter  Jason Beringer  Damien Bonal  Baozhang Chen  Jiquan Chen  Robert Clement  Kenneth J. Davis  Ankur R. Desai  Danilo Dragoni  Sophia Etzold  Thomas Grünwald  Lianhong Gu  Bernhard Heinesch  Lucy R. Hutyra  Wilma W.P. Jans  Werner Kutsch  B.E. Law  Monique Y. Leclerc  Ivan Mammarella  Leonardo Montagnani  Asko Noormets  Corinna Rebmann  Sonia Wharton 《Agricultural and Forest Meteorology》2009,149(11):1919

Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u_*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u_*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F_C) and change in storage (F_S) of CO₂ in the few hours after sundown. The sum of F_C and F_S reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R_Rmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F_c + F_s extrapolated to zero light, R_LRC, and (3) with a detailed process-based forest ecosystem model, R_cast. At most sites respiration rates estimated using the u_*-filter, R_ust, were smaller than R_Rmax and R_LRC. Agreement of our approach with independent measurements indicates that R_Rmax provides an excellent estimate of nighttime ecosystem respiration.  相似文献   

Search for <Emphasis Type="Italic">Salmonella</Emphasis> spp. in ostrich productive chain of Brazilian southeast region     

Oliveiro Caetano de Freitas Neto  Sonia Luisa Silva Lages  Adriano Oliveira Torres Carrasco  Angelo Berchieri Junior 《Tropical animal health and production》2009,41(8):1607-1614

We analyzed ostriches from an equipped farm located in the Brazilian southeast region for the presence of Salmonella spp. This bacterium was investigated in 80 samples of ostrich droppings, 90 eggs, 30 samples of feed and 30 samples of droppings from rodents. Additionally, at slaughter-house this bacterium was investigated in droppings, caecal content, spleen, liver and carcasses from 90 slaughtered ostriches from the studied farm. Also, blood serum of those animals were harvested and submitted to serum plate agglutination using commercial Salmonella Pullorum antigen. No Salmonella spp. was detected in any eggs, caecal content, liver, spleen, carcass and droppings from ostriches and rodents. However, Salmonella Javiana and Salmonella enterica subsp. enterica 4, 12: i:- were isolated from some samples of feed. The serologic test was negative for all samples. Good sanitary farming management and the application of HACCP principles and GMP during the slaughtering process could explain the absence of Salmonella spp. in the tested samples.  相似文献   

Retrospective serological study on hepatitis E infection in pigs from 1985 to 1997 in Spain     

Casas M  Pujols J  Rosell R  de Deus N  Peralta B  Pina S  Casal J  Martín M 《Veterinary microbiology》2009,135(3-4):248-252

The objective of the present work was to ascertain the date in which hepatitis E virus (HEV) was introduced in the Spanish pig population. For this, a serological retrospective study was carried out using archived sera. A total of 2871 serum samples gathered between 1985 and 1997 and collected in 208 farms of Spain were tested for anti-HEV IgG by an in-house ELISA. Of the 2871 sera analyzed by ELISA, 1390 were positive for anti-HEV antibodies (48.4%, 95% CI: 46.9-49.9%) and that corresponded to 204/208 farms (98%, 95% CI: 96.1-99.9%) having at least one positive pig. Our results show that HEV was present and widespread in Spanish swine farms at least since 1985. Any significant changes in prevalence were detected from 1 year to another and therefore, HEV infection in swine should be considered endemic in Spain.  相似文献   

Modeling bleaching of tomato derivatives at subzero temperatures     

Manzocco L  Calligaris S  Nicoli MC 《Journal of agricultural and food chemistry》2006,54(4):1302-1308

This work was addressed to obtain a predictive model of the rate of bleaching in tomato derivatives at subzero temperatures. To this aim, a tomato puree was freeze-dried and equilibrated at increasing solid fractions. The bleaching rate was assessed by measuring tomato color during storage for up to 18 months at temperatures from -30 to 0 degrees C. The temperature dependence of the tomato-bleaching rate was neither predictable using the Arrhenius equation nor simply related to tomato physical state. The lack of a clear Arrhenius relation was attributed to the occurrence of temperature-dependent phenomena, such as ice crystallization and oxygen solubility modifications, which strongly changed the local concentration of reactants. A modified Arrhenius equation predicting the tomato-bleaching rate in the entire temperature range was proposed. Tomato concentration, and hence its physical state, affected the temperature dependence of bleaching, modifying apparent activation energy and frequency factor of the modified Arrhenius equation. In light of these considerations, a mathematical model was set up and validated to accurately predict the tomato-bleaching rate on the basis of only its concentration and storage temperature.  相似文献   

Ranking temperate woody species along a gradient of browsing by deer     

Vincent Boulanger  Christophe Baltzinger  Sonia Saïd  Philippe Ballon  Jean-Franois Picard  Jean-Luc Dupouey 《Forest Ecology and Management》2009,258(7):1397-1406

As a result of diverse management policies, densities of red and roe deer have varied considerably for the last few decades in Europe. Their selective browsing on woody species can modify the interactions between competing species and thus change overall patterns of plant diversity in forests. However, no classification of woody species according to browsing by deer yet exists in Europe. The selectivity index, which measures the balance between availability and consumption of plant species by herbivores, could be used for such a classification. The aim of this study was, first, to rank woody species according to this selectivity index, then to test whether their rank changed when browsing pressure varied in space or time. We also explored morphological and ecological life traits (Ellenberg indicator values) that might explain differences in selectivity.In 2006, we re-sampled a network of 217 coupled floristic and browsing survey plots, which had been previously described twice (1976, 1981). The plots were located in the forest of Arc-en-Barrois (France), a large woodland area divided into a North and a South Forest which have had different histories of browsing pressure.For the three samples and the two forests, we calculated a selectivity index for 19 woody species. Dogwood (Cornus sp.) and field rose (Rosa arvensis) appeared to be the most selected species whereas beech (Fagus sylvatica), common mezereon (Daphne mezereum) and wild-service tree (Sorbus torminalis) were always avoided. The rank order of species according to their selectivity index remained stable over the three sample years and between the two forests (Spearman's rank correlations: ρ ≈ 0.8 spatially, and range from 0.3 to 0.8 temporally). This indicates that variations in browsing pressure did not strongly modify deer selectivity patterns. Selectivity was positively correlated with wood density and negatively correlated with maximum height of the species, but unrelated to other plant traits. Finally, selectivity can be seen as an intrinsic characteristic of those woody species, and could be used as an additional life trait when analyzing vegetation communities.  相似文献   

Potential productivity of forested areas based on a biophysical model. A case study of a mountainous region in northern Spain     

Raquel Benavides  Sonia Roig  Koldo Osoro 《Annals of Forest Science》2009,66(1):108-108

? Today’s forest managers face a number of important challenges involving an increasing need for precise estimates of forest structure and biomass, potential productivity or forest growth. The objective is to develop a model for potential productivity in a mountainous region of Spain. The model combines climatic, topographic and lithological data using a variant of a traditional biophysical model: the Paterson index.

? In a first approach, the climatic productivity is assessed by modelling the required parameters using different geostatistical techniques and software supported by GIS. A second approach includes the correction of the former productivity classes considering the different lithological facies. The potential forest productivity model involves the integration of both models.

? Finally, data from the National Forest Inventory (NFI) are used to compare the real and potential yield data within different regions of the studied area.

? The results of these analyses demonstrate the usefulness of the model, particularly in mountainous regions, where no significant differences are found between the data from the NFI and the model, but they also show the discrepancies between the estimates and real data when the latter are considered for different tree species, diameter classes or management.

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Erratum to: Incidence and Characterization of <Emphasis Type="Italic">Potato Virus Y</Emphasis> in Seed Potatoes in Tunisia     

Sonia Boukhris-Bouhachem  J. Rouze-Jouan  N. Khamassi  Fattouma Djilani-Khouadja  Hatem Fakhfakh  Laurent Glais  Michel Tribodet  Camille Kerlan 《Potato Research》2011,54(3):283

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