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131.
Francesca Cardinale Lucia Ferraris Danila Valentino Giacomo Tamietti 《Physiological and Molecular Plant Pathology》2006,69(4-6):160-171
A polynucleate Rhizoctonia isolate (R3) was analysed for virulence, growth characteristics, enzyme production and presence of dsRNAs. Taxonomic position was assessed morphologically and by anastomosis group (AG) testing and ITS sequence analysis. Results indicated that R3 is a hypovirulent R. solani AG 4. Mechanisms underlying biocontrol towards virulent R. solani and Botrytis cinerea were investigated and plant-mediated resistance was followed using biochemical markers of defence (PR1, laminarinase, chitinase). Control apparently relies on spatial and nutrient competition in soil, and on systemic induced resistance. This is the first report on induction of systemic resistance and of defence markers by a hypovirulent strain of R. solani. 相似文献
132.
Endogenous opioid binding to micro receptors is hypothesized to mediate natural rewards and has been proposed to be the basis of infant attachment behavior. Here, we report that micro-opioid receptor knockout mouse pups emit fewer ultrasonic vocalizations when removed from their mothers but not when exposed to cold or male mice odors. Moreover these knockout pups do not show a preference toward their mothers' cues and do not show ultrasonic calls potentiation after brief maternal exposure. Results from this study may indicate a molecular mechanism for diseases characterized by deficits in attachment behavior, such as autism or reactive attachment disorder. 相似文献
133.
Andrea Minuto Francesca Clematis Maria Lodovica Gullino Angelo Garibaldi 《Phytoparasitica》2007,35(1):77-85
Tomatoes grown in soilless systems can be seriously damaged byFusarium oxysporum Schlect f.sp.radicis lycopersici (Forl) causing Fusarium crown and root rot (FCRR). FCRR suppression can be achieved through the use of chemicals, selected substrates,
composts and artificially introduced antagonistic microorganisms. This study evaluated the natural capacity of a used rockwool
to suppress FCRR infections. New and used rockwool, sampled from closed soilless systems, was either autoclaved or not, either
artificially inoculated withForl or not and, finally, sown with tomato seeds cv. ‘Cuore di Bue’. The effects of autoclaved/non-autoclaved and used/new rockwool
on FCRR incidence were assessed by evaluating the symptoms of crown rot on the root — shoot transition zone of tomato seedlings.
Non-autoclaved and inoculated used rockwool significantly reduced FCRR incidence when compared with non-autoclaved and inoculated
new rockwool. Autoclaved and inoculated used rockwool did not suppress FCRR, similarly to new and inoculated rockwool. These
findings are in accordance with other research that, on a cucumber/Pythium host/pathogen complex in a closed rockwool soilless system, demonstrated the key role of resident microflora in suppressing
the root rot disease.
http://www.phytoparasitica.org posting Dec. 8, 2006. 相似文献
134.
Giuseppe Ignazzitto Laura Volterra Francesca A. Aulicino Anna M. D'Angelo 《Water, air, and soil pollution》1980,13(4):391-398
The potential use of coliphages as indicators of water pollution was investigated. Several strains ofE. coli hosts were used in order to detect the better marker. Analyses were carried out on a treatment plant for the convenience of phages recoveries. Results show the possibility that strains different fromE. coli 9484B can show better recoveries of PFU m1?1. 相似文献
135.
Increased nitrogen-use efficiency of a short-rotation poplar plantation in elevated CO(2) concentration 总被引:1,自引:0,他引:1
Calfapietra C Angelis Pd Gielen B Lukac M Moscatelli MC Avino G Lagomarsino A Polle A Ceulemans R Mugnozza GS Hoosbeek MR Cotrufo MF 《Tree physiology》2007,27(8):1153-1163
We estimated nitrogen (N) use by trees of three poplar species exposed for 3 years to free air CO(2) enrichment (FACE) and determined whether the CO(2) treatment affected the future N availability of the plantation. Trees were harvested at the end of the first 3-year rotation and N concentration and content of woody tissues determined. Nitrogen uptake of fine roots and litter was measured throughout the first crop rotation. The results were related to previously published variations in soil N content during the same period. We estimated retranslocation from green leaves and processes determining N mobilization and immobilization, such as mineralization and nitrification, and N immobilization in litter and microbial biomass. In all species, elevated CO(2) concentration ([CO(2)]) significantly increased nitrogen-use efficiency (NUE; net primary productivity per unit of annual N uptake), decreased N concentration in most plant tissues, but did not significantly change cumulative N uptake by trees over the rotation. Total soil N was depleted more in elevated [CO(2)] than in ambient [CO(2)], although not significantly for all soil layers. The effect of elevated [CO(2)] was usually similar for all species, although differences among species were sometimes significant. During the first 3-year rotation, productivity of the plantation remained high in the elevated [CO(2)] treatment. However, we observed a potential reduction in N availability in response to elevated [CO(2)]. 相似文献
136.
Thomas Balenghien Nonito Pagès Maria Goffredo Simon Carpenter Denis Augot Elisabeth Jacquier Sandra Talavera Federica Monaco Jérôme Depaquit Colette Grillet Joan Pujols Giuseppe Satta Mohamed Kasbari Marie-Laure Setier-Rio Francesca Izzo Cigdem Alkan Jean-Claude Delécolle Michela Quaglia Rémi Charrel Andrea Polci Emmanuel Bréard Valentina Federici Catherine Cêtre-Sossah Claire Garros 《Preventive veterinary medicine》2014
Schmallenberg virus (SBV), a novel arboviral pathogen, has emerged and spread across Europe since 2011 inflicting congenital deformities in the offspring of infected adult ruminants. Several species of Culicoides biting midges (Diptera: Ceratopogonidae) have been implicated in the transmission of SBV through studies conducted in northern Europe. In this study Culicoides from SBV outbreak areas of mainland France and Italy (Sardinia) were screened for viral RNA. The role of both C. obsoletus and the Obsoletus complex (C. obsoletus and C. scoticus) in transmission of SBV were confirmed in France and SBV was also discovered in a pool of C. nubeculosus for the first time, implicating this species as a potential vector. While collections in Sardinia were dominated by C. imicola, only relatively small quantities of SBV RNA were detected in pools of this species and conclusive evidence of its potential role in transmission is required. 相似文献
137.
138.
Francesca Cecchi Roberta Ciampolini Gianluca Giacalone Gisella Paci 《Animal Science Journal》2014,85(9):868-871
The genealogical data of 471 (whole population: WP) Lizard canaries of an Italian breeder were analyzed to evaluate the genetic variability of the breed. The reference population (RP) comprised 346 living reproductive birds. Average generation interval was 1.61 ± 0.718 for males and 1.72 ± 0.863 for females. The average value of inbreeding (F) and relatedness (AR) in the RP were 15.83% and 22.63%, while the average increase in inbreeding was estimated to be 6.71% per generation (effective population size = 7.49). The results showed the need to reduce the level of inbreeding which would result in significant loss of genetic variation and in significant inbreeding depression. 相似文献
139.
Ruggero D Grisendi S Piazza F Rego E Mari F Rao PH Cordon-Cardo C Pandolfi PP 《Science (New York, N.Y.)》2003,299(5604):259-262
Mutations in DKC1 cause dyskeratosis congenita (DC), a disease characterized by premature aging and increased tumor susceptibility. The DKC1 protein binds to the box H + ACA small nucleolar RNAs and the RNA component of telomerase. Here we show that hypomorphic Dkc1 mutant (Dkc1m) mice recapitulate in the first and second generations (G1 and G2) the clinical features of DC. Dkc1m cells from G1 and G2 mice were impaired in ribosomal RNA pseudouridylation before the onset of disease. Reductions of telomere length in Dkc1m mice became evident only in later generations. These results suggest that deregulated ribosome function is important in the initiation of DC, whereas telomere shortening may modify and/or exacerbate DC. 相似文献
140.
Modugno G Roati G Riboli F Ferlaino F Brecha RJ Inguscio M 《Science (New York, N.Y.)》2002,297(5590):2240-2243
A degenerate gas of identical fermions is brought to collapse by the interaction with a Bose-Einstein condensate. We used an atomic mixture of fermionic potassium-40 and bosonic rubidium-87, in which the strong interspecies attraction leads to an instability above a critical number of particles. The observed phenomenon suggests a direction for manipulating fermion-fermion interactions on the route to superfluidity. 相似文献