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101.
Alejandro Solla Lorena García Andrea Pérez Ana Cordero Elena Cubera Gerardo Moreno 《Phytoparasitica》2009,37(4):303-316
The Iberian forests are suffering severe disease and mortality as a result of decline, with Quercus ilex the major species at risk. Trunk injections with potassium phosphonate, which have been used successfully to control Phytophthora cinnamomi, were tested against decline. In an area in which P. cinnamomi was isolated, Q. ilex trees showing different degrees of decline were trunk-injected. Soil properties, and measurements of soil water content (θ)
and depth to soil water table were assessed at three sites with markedly different decline incidences. Over the 5 years following
the initiation of the experiment, mean symptoms among spring-treated trees and autumn-treated trees, or among trees injected
twice a year (spring and autumn), once a year, and non-injected, were not significantly different. No effects of the treatments
on shoot growth and acorn production were observed. However, θ values under trees which recovered from decline were higher
than θ values under trees which did not recover from decline. At the site with the highest incidence of decline and tree mortality,
P. cinnamomi was rarely isolated, and the presence of gravel, soil infiltration capacities and water table depth values were significantly
higher than at the other sites, water stress being more likely to contribute to decline than P. cinnamomi. In areas in which θ is low, the distribution of phosphonate on the tree would be limited. Since the thresholds for phytotoxicity
of potassium phosphonate in Q. ilex trees at the site studied would be higher than the amounts used, rates of the chemical slightly less than those that cause
phytotoxicity should be tested. 相似文献
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105.
Brownlee D Tsou P Aléon J Alexander CM Araki T Bajt S Baratta GA Bastien R Bland P Bleuet P Borg J Bradley JP Brearley A Brenker F Brennan S Bridges JC Browning ND Brucato JR Bullock E Burchell MJ Busemann H Butterworth A Chaussidon M Cheuvront A Chi M Cintala MJ Clark BC Clemett SJ Cody G Colangeli L Cooper G Cordier P Daghlian C Dai Z D'Hendecourt L Djouadi Z Dominguez G Duxbury T Dworkin JP Ebel DS Economou TE Fakra S Fairey SA Fallon S Ferrini G Ferroir T Fleckenstein H Floss C Flynn G 《Science (New York, N.Y.)》2006,314(5806):1711-1716
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales. 相似文献
106.
García-Hernández Y Rodríguez Z Brandão LR Rosa CA Nicoli JR Elías Iglesias A Peréz-Sanchez T Salabarría RB Halaihel N 《Research in veterinary science》2012,93(2):798-802
The objective of this study was to isolate and identify yeast strains from broilers excreta and to evaluate in vitro their potential for probiotic use in animal production.Methods and resultsNine yeast strains were isolated and presumptively pre-identified by biochemical assays. These isolates were grouped in six different molecular profiles using PCR-fingerprinting technique. Each profile was identified by sequencing of the D1/D2 domains of the large subunit of the 26S rRNA gene. These yeasts were identified as: Trichosporon sp. (LV-2), Wickerhamomyces anomalus (LV-6), Pichia kudriavzevii (LV-8), Kodamaea ohmeri (LV-9) and Trichosporon asahii (LV-10). A pre-screening of the strains for probiotic use was based on their ability to agglutinate pathogenic micro-organisms. These yeast strains were characterized for specific growth rate, duplication time, their cell surface hydrophobicity, medium acidification, resistance to low pH (2.0, 2.5 and 3.0) and concentrations of bile salts (0.3% and 0.6%). The isolate of W. anomalus (LV-6) had the highest agglutinating and adherence capacity, a growth rate of 2.07 × 108 cfu/mL in 24 h at 30 °C, decreasing the medium pH from 6.5 to 5.23, a 25% hydrophobicity and an elevated capacity to grow under stress conditions.ConclusionsW. anomalus strain LV-6 showed the best characteristics for use as a probiotic candidate.Significance and impact of the Study:The data from this study helped in choosing a probiotic candidate from yeast to use in broiler production. 相似文献
107.
108.
Characterization of a Potential Nutraceutical Ingredient: Pomegranate (Punica granatum L.) Seed Oil Unsaponifiable Fraction 总被引:1,自引:1,他引:0
Augusta Caligiani Francesca Bonzanini Gerardo Palla Martina Cirlini Renato Bruni 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):277-283
The chemical fingerprinting of the unsaponifiable fraction of different Punica granatum seed oils was performed in order to evaluate their potential as a functional food ingredient. Qualitative and quantitative
determinations of tocopherol, aliphatic alcohol (including policosanol), squalene, phytosterols and triterpene contents were
performed by GC-MS. A high yield (3.1–4.2%) of unsaponifiable matter was obtained and consistent levels of squalene (up to
800 mg/kg) and policosanol (118–185 mg/kg) were noticed. β-sitosterol (up to 8069 mg/kg) and cycloartenol (5916–7766 mg/kg)
were predominant in phytosterol and triterpene fractions, while β- and δ-tocopherol were the most abundant vitamin E forms.
Some minor variations were noticed between samples. From the results obtained, it can be suggested that the seed oil of P. granatum can be considered an interesting alimentary source of substances of nutraceutical value involved in the modulation of cholesterol
metabolism. 相似文献
109.
Long‐term epidemiological study of disseminated neoplasia of cockles in Galicia (NW Spain): temporal patterns at individual and population levels,influence of environmental and cockle‐based factors and lethality
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The dynamics of disseminated neoplasia (DN) affecting cockles Cerastoderma edule (L.) in Galicia was addressed at individual and population levels. Early stage of DN was characterized by isolated neoplastic cells occurring in branchial vessels or in the connective tissue of gills, mantle, gonad or digestive gland. As disease progressed, the neoplastic cells appeared loose in foci and became widely distributed throughout the organs. In advanced stages, the connective tissue of most organs was infiltrated by neoplastic cells, which displaced normal cells, leading to the loss of the normal tissue/organ architecture. Host defence reaction was occasionally observed. A field survey performed for 7 years, in two cockle beds located in different Galician Rías, showed that DN is a hyperendemic disease usually present all year‐round at high prevalence in adult cockles but with annual prevalence minima in spring likely due to the death of heavily affected cockles, concurrently with gonad ripeness–spawning. DN was detected in the cockles ranging from 10 to 39 mm in size; the highest DN prevalence and severity corresponded to the cockles of intermediate size/age (22–29 mm/0.7–1 year old). Sex did not appear to influence DN occurrence. An inhibitory effect of DN on cockle gametogenesis was detected. 相似文献
110.
José Martínez-Calvo Ana Delia Gisbert M. Carmen Alamar Rosa Hernandorena Carlos Romero Gerardo Llácer María L. Badenes 《Genetic Resources and Crop Evolution》2008,55(5):695-703
Loquat species (Eriobotrya japonica Lindl.) originated in China, later was introduced in Japan. However, introduction in Europe occurred much later, in 18th
century, it was introduced as an ornamental tree. Since then, the species was very well adapted to the Mediterranean climate,
mainly in South East of Spain, where is located more than 50% of total European crop production. A European Project titled
‘Conservation, evaluation and collection of underutilized fruit species’ supported surveys and collection of plant material
from these species in the Mediterranean basin countries. One of these surveys resulted in a germplasm collection of loquat
established at IVIA, Valencia, Spain. This collection is being extended with new accessions collected across the world, currently
the collection have 123 accessions under study. Germplasm management needs first a characterization of the plant material
introduced and second diversity studies into the collection that could point out the variability pattern, to establish groups
of accessions with similar traits and the most significant variables. These results allow organizing the information gathered
for further uses. In this paper, 62 accessions from the IVIA germplasm collection were studied. Results from 43 variables
were gathered and data studied by multivariate analysis. The analysis allowed summarizing the data tables with new variables
containing most of the information. These results along with those obtained in the coming years will allow define a nuclear
collection (minimum number of accessions that contained all the variability present in the collection). 相似文献