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José L. Santiago Susana BosoPilar Gago Virginia Alonso-VillaverdeMaría Carmen Martínez 《Scientia Horticulturae》2008
The arrival of powdery mildew, phylloxera, and then downy mildew from America in the late 19th/early 20th century, was one of the most important causes of the loss of grapevine diversity in Europe. Many varieties traditionally grown in small winemaking areas of Europe were substituted by direct producing hybrids or by a small number of varieties from other vine-growing areas. For geographic, economic, sociological, and cultural reasons, the north and northwest of Spain acts as a kind of refuge area where grapevine diversity is still high. At the Misión Biológica de Galicia (CSIC) research station a collection of living vines with a number of dispersed individuals belonging to old varieties was established in 1992. Many of these varieties had practically disappeared from vineyards and the majority existed only as centuries-old individuals. 相似文献
64.
Federico Marziali Julian Acosta Elisa Bolatti Santiago Mirazo Patricia Skejich Patricia Silva Julie Brassard Alejandro Costaguta Daniela Gardiol Ana Laura Cavatorta 《Zoonoses and public health》2019,66(7):729-738
Hepatitis E virus (HEV) is currently considered as a global health concern due to the recognition of its zoonotic transmission to humans, mainly from swine, and its association with the development of severe cases of hepatitis in human risk populations. The lack of updated data on HEV state of infection in swineherds of Argentina, and the necessity of robust technologies for its detection in complex biological samples, positions HEV as an emerging issue in public health. Here, we have optimized a RT‐qPCR with internal control for a more precise and accurate HEV RNA detection in swine stool samples. We implemented this optimized molecular tool to analyse the current epidemiological scenario of HEV infection in swine from the core region of commercial activity of Argentina. A total of 135 stool samples were collected from 16 different farms and tested for HEV presence, resulting in 11 positive cases (8.1%). Phylogenetic analysis demonstrated that all of them correspond to HEV genotype 3 and that different subtypes circulate in the region. Moreover, two of the detected strains presented a high nucleotide similarity with a previously identified isolate from human sewage discharges, suggesting the zoonotic transmission of HEV to humans. Collectively, this work provides a better understanding of HEV epidemiology in Argentina while contributes to the improvement of HEV detection technologies. 相似文献
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ABSTRACT Phytophthora root and stem rot of soybeans caused by Phytophthora sojae is a serious limitation to soybean production in the United States. Partial resistance to P. sojae in soybeans is effective against all the races of the pathogen and is a form of incomplete resistance in which the level of colonization of the root is reduced following inoculation. Other forms of incomplete resistance include the single dominant gene Rps2 and Ripley's root resistance, which are both race-specific. To differentiate partial resistance from the other types of incomplete resistance, the components lesion length, numbers of oospores, and infection frequency were measured in eight soybean genotypes inoculated with two P. sojae isolates. The Rps2 and root-resistant genotypes had significantly lower oospore production and infection frequency compared with the partially resistant genotype Conrad, while the root-resistant genotype also had significantly smaller lesion lengths. However, the high levels of partial resistance in Jack were indistinguishable from Rps2 in L76-1988, based on the evaluation of these components. Root resistance in Ripley and Rps2 in L76-1988 had similar responses for all components measured in this study. Partial resistance expressed in Conrad, Williams, Jack, and General was comprised of various components that interact for defense against P. sojae in the roots, and different levels of each component were found in each of the genotypes. However, forms of incomplete resistance expressed via single genes in Ripley and Rps2 in L76-1988, could not be distinguished from high levels of partial resistance based on lesion length, oospore production, and infection frequency. 相似文献
67.
A.?ButrónEmail author G.?Sandoya R.?Santiago A.?Ordás A.?Rial R.?A.?Malvar 《Genetic Resources and Crop Evolution》2006,53(7):1455-1462
The pink stem borer (Sesamia nonagrioides Lef.) is the main corn (Zea mays L.) pest in the Mediterranean area. Although, screening for resistance to this pest has been successful, the level of resistance
shown by the most resistant varieties is not high. The objectives of the present work were: (i) the evaluation for pink stem
borer resistance of the nontested inbred lines, field and popcorn materials, from the collection maintained at the Misión
Biológica de Galicia and (ii) the study of the performance, under pink stem borer infestation, of inbreds selected for resistance
to pink stem borer in hybrid combination. Forty four inbred lines nontested yet for resistant to pink stem borer along with
five inbred lines previously reported as resistant to stem and ear attack, were evaluated in 2002 and 2003. In adjacent experiments,
hybrids EP79× W552, EP77× B93, and A661× EP42 were tested along with a resistant hybrid, MEB531-Bt, and a susceptible hybrid, INRA 260. New sources of resistance to pink stem borer have been detected among inbred lines improving
the level of resistance presented by previously tested inbreds. Some of these lines were successfully developed by pedigree
selection for resistance to pink stem borer. 相似文献
68.
Connectivity providers for semi-aquatic vertebrates: the case of the endangered otter in Italy 总被引:1,自引:0,他引:1
Maria Laura Carranza Evelina D’Alessandro Santiago Saura Anna Loy 《Landscape Ecology》2012,27(2):281-290
Modeling habitat connectivity for conservation of semi-aquatic vertebrates is a particularly challenging task, due to the
fine-scale and linear distribution of riverine habitats and to the capacity of species to move both on freshwater and terrestrial
realms. We showed how the integrated analytical framework provided by the habitat availability (reachability) metrics and
their fractions can be used to effectively evaluate the distinctive roles and contributions of both habitat patches (aquatic
and riparian) and linkage areas (permeable land matrix) to the connectivity and functioning of a complex system composed of
multiple river catchments. Analysis focused on the Eurasian otter (Lutra lutra L.), one of the most endangered mammals in Italy. We developed a network connectivity model based on suitable otter habitats
and multiple least-cost paths between catchments. A graph analytical approach was used to identify critical nodes and links
for the potential expansion and long-term viability of the species in the region. Our results showed that few basins concentrate
most of the importance for sustaining the overall habitat connectivity, due to the extension of suitable habitats they contain,
their strong connections with other basins, and their importance as stepping stones that uphold ecological fluxes between
otherwise weakly connected habitats. The potential contribution of each basin to enhance the dispersal and expansion of otters
in the area strongly depended on the key functional paths (sequences of links and nodes) among the catchments. We identified
vacant basins that could be colonized by otters in the near future, and connecting areas in the intermediate matrix that might
be preferentially used to conduct and promote dispersal movements and gene flow in the area. The novel approach here adopted
could be easily extended to other semiaquatic species and catchment systems, offering a management strategy to preserve the
hydrographic network as an integrated system, as well as a joint evaluation of the role of both the river courses and the
matrix in between in a single landscape model. 相似文献
69.
Mediterranean landscapes are suffering two opposing forces leading to large-scale changes in species distribution: land abandonment
of less productive areas and an increase in wildfire impact. Here, we test the hypothesis that fires occurred in recent decades
drive the pattern of expansion of early-successional, open-habitat bird species by aiding in the process of colonisation of
newly burnt areas. The study was carried out in Catalonia (NE Spain). We selected 44 burnt sites occurring between 2000 and
2005 to model colonisation patterns under different assumptions of potential colonisers’ sources and evaluated the colonisation
estimates with empirical data on six bird species especially collected for this purpose. We first defined three landscape
scenarios serving as surrogates of potential colonisers’ sources: open-habitats created by fire, shrublands and farmlands.
Then, we used a parameter derived from a functional connectivity metric to estimate species colonization dynamics on the selected
sites by each particular scenario. Finally, we evaluated our colonisation estimates with the species occurrence in the studied
locations by using generalized linear mixed models. The occurrence of the focal species on the newly burnt sites was significantly
related to the connectivity patterns described by both the recent fire history and the other open-habitat types generated
by a different type of disturbance. We suggest that land use changes in recent decades have produced a shift in the relative
importance of habitats acting as reservoirs for open-habitat bird species dynamics in Mediterranean areas. Before the middle
of the twentieth century species’ reservoirs were probably constituted by relatively static open habitats (grassland and farmland),
whereas afterwards they likely consist of a shifting mosaic of habitat patches where fire plays a key role as connectivity
provider and largely contributes to the maintenance of species persistence. 相似文献
70.
Pablo G. Acosta-Quezada Santiago Vilanova Juan B. Martínez-Laborde Jaime Prohens 《Euphytica》2012,187(1):87-97
Tree tomato (Solanum betaceum) is an Andean small tree cultivated for its juicy fruits. Little information is available on the characterization of genetic resources and breeding of this neglected crop. We have studied the molecular diversity with AFLP markers using 11 combinations of primers of a collection of 25 S. betaceum accessions belonging to four cultivar groups, most of which had been previously morphologically characterized, as well as one accession of the wild relative S. cajanumense. A total of 197 AFLP fragments were scored, of which 84 (43 %) were polymorphic. When excluding S. cajanumense from the analysis, the number of polymorphic AFLP fragments was 78 (40 %). Unique AFLP fingerprints were obtained for every accession, but no AFLP fragments specific and universal to any of the four cultivar groups were found. The total genetic diversity (H T ) of cultivated accessions was H T = 0.2904, while for cultivar groups it ranged from H T = 0.1846 in the orange group to H T = 0.2498 in the orange pointed group. Genetic differentiation among cultivar groups (G ST ) was low (G ST = 0.2248), which was matched by low values of genetic distance among cultivar groups. The diversity of collections from Ecuador, which we hypothesize is a center of diversity for tree tomato, was similar to that from other origins (H T = 0.2884 and H T = 0.2645, respectively). Cluster and PCoA analyses clearly separated wild S. cajanumense from the cultivated species. However, materials of different cultivar groups and origins were intermingled in both analyses. The Mantel test correlation coefficient of the matrices of morphological and AFLP distances was low (−0.024) and non-significant. Overall, the results show that a wide diversity is present in each of the cultivar groups, indicate that Ecuador may be regarded as a center of accumulation of diversity for this crop, and confirm that AFLP and morphological characterization data are complementary. The results obtained are of value for the conservation of genetic resources and breeding of tree tomato, as an assessment of the genetic diversity and relationships among different cultivar groups and geographic origins is obtained. 相似文献