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排序方式: 共有489条查询结果,搜索用时 187 毫秒
471.
Maria Paola Ferranti Javier Guallart Virginia Cortella Giacomo Terenziani Mariachiara Chiantore 《水产资源保护:海洋与淡水生态系统》2021,31(7):1912-1917
- Effectiveness of restoration/repopulation measures may be strongly hindered by the ability of the target species to cope with the environmental conditions of the receiving area.
- Although a species has been reported previously for a given area, the environmental conditions and human pressures may have changed, potentially making any restoration attempt ineffective. Evidence is provided showing that the endangered ferruginous limpet Patella ferruginea can complete its reproductive cycle in the northernmost sector of the western Mediterranean.
- This supports the idea that the reintroduction and the strict protection of P. ferruginea in the extreme north of its historical geographic range could be effective for the recovery of the species in this area and ultimately the establishment of reproductively viable and stable populations.
- Verification of gonadal maturation of specimens experimentally established on the Gulf of Genoa (Ligurian Sea) coastline, as well as evidence of sex change in one individual (the first outside the Alboran Sea), provides further support of the potential for individuals to complete their reproductive cycle in this area.
- The results support the potential of actions for the restoration of viable populations of the species along the Ligurian coasts through the introduction of juveniles obtained exclusively by aquaculture techniques, in order to mitigate any impact on donor sites.
472.
473.
Adriana E. Lenardis Catalina van Baren Paola Di Leo Lira Claudio M. Ghersa 《European Journal of Agronomy》2007,26(4):410-417
Arthropod assemblies are frequently determined by bottom-up interactions that include emission of organic volatile compounds. Therefore, changes in soil characteristics associated with land use history can influence the volatile emissions of plants affecting the structure of arthropod assemblies in croplands. This study aims (1) to study the relationships between soil degradation levels due to land-use history, and the change in particular soil chemical characteristics; (2) to analyze plant–soil interactions quantifying the effect of soil degradation on the production of biomass and grain yield of coriander and wheat crops, and on the production and chemical composition of volatile secondary metabolites in coriander grain; (3) to find the relationship between the analyzed plant–soil interactions and the emission of volatile signals affecting arthropod assemblies; and (4) to determine the relationship between particular chemical soil characteristics and the structure of arthropod assemblies. For these purpose, two experiments were carried out in which volatile compounds were conducted from source plots with soils with different levels of degradation, sown with wheat or coriander, to sink plots with similar soil, sown with wheat. Crops were evaluated on source plots, and the arthropods communities were assessed on sink-plots. Coriander produced high biomass, grain yield and essential oil in the favorable environments and wheat produced higher biomass and grain yield in soil with low degradation than with high degradation. Particular chemical soil elements, for example, Na, Fe, Mn, N and CEC and essential oil components, for example, γ-trepanned, p-cymene, asinine and β-pinene could be involved in the arthropods assemblies. Based on these results, arthropods communities in agricultural systems are, at least, partially controlled by chemical signals, which depend on plant–soil interactions. 相似文献
474.
Paola D. Fontana Alejandro M. Rago Cecilia A. Fontana Graciela M. Vignolo Pier S. Cocconcelli Jorge A. Mariotti 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(3):525-534
Red stripe is a bacterial disease of sugarcane causing important economic losses in Argentina that affects 30 % of the milling stems and consequently the juice quality. In this study, sugarcane leaves exhibiting red stripe symptoms were sampled in the 2008–09 growing season from 13 different sugarcane producing areas of Tucumán and Salta (northwest of Argentina). To achieve the identification and characterization of the causal agent of red stripe, bacterial isolation was performed. Species-specific PCR using Oaf1/Oar1 primers allowed the amplification of a fragment of 550 bp from approximately 50 % of the isolates; 16S rDNA sequences analysis displayed a similarity greater than 99 % with Acidovorax avenae subsp. avenae. By means of RAPD-PCR the presence of at least four different biotypes among the analyzed isolates was detected. Results of pathogenicity test allowed us to confirm A. avenae subsp. avenae as the pathogenic agent for red stripe. This study constitutes the first report on the identification and molecular characterization of this plant pathogen from the Argentina sugarcane production areas. The genetic diversity observed among A. avenae is an important factor to be considered to improve an accurate diagnosis and/or the selection of sugarcane tolerant clones. 相似文献
475.
Gabriela Burgos Lupita Muñoa Paola Sosa Merideth Bonierbale Thomas zum Felde Carlos Díaz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):385-390
Yellow fleshed potatoes contain significant amounts of lutein and zeaxanthin but the bioaccessibility of potato carotenoids has not yet been investigated. The purpose of this study was to estimate the in vitro bioaccessibility of carotenoids provided by potato. Lutein and zeaxanthin concentrations of boiled, freeze dried and milled samples of seven yellow fleshed potato accessions were determined by HPLC before and after different steps (gastric, duodenal and micellar phase) of in vitro digestion. The gastric and duodenal digestive stability of lutein and zeaxanthin in boiled tubers of the different accessions ranged from 70 to 95 % while the efficiency of micellarization ranged from 33 to 71 % for lutein and from 51 to 71 % for zeaxanthin. For all accessions, amounts of lutein and zeaxanthin after micellarization were significantly lower than the original amount found in the boiled samples. The accession 701862 showed the highest bioaccessible lutein concentration (280 μg/100 g, FW) and the accessions 703566 and 704218 showed the highest bioaccessible zeaxanthin concentration (above 600 μg/100 g, FW). Considering the mean potato intake in the Andes (500 g per day), the accession 701862 provides 14 % of the lutein intake suggested for health benefits and the accessions 703566 and 704218 provide 50 % more than the suggested zeaxanthin intake. 相似文献
476.
Vitaglione P Barone Lumaga R Ferracane R Radetsky I Mennella I Schettino R Koder S Shimoni E Fogliano V 《Journal of agricultural and food chemistry》2012,60(13):3357-3366
Human bioavailability of curcumin from breads enriched with 1 g/portion of free curcumin (FCB), encapsulated curcumin (ECB), or encapsulated curcumin plus other polyphenols (ECBB) was evaluated. Parental and metabolized curcuminoids and phenolic acids were quantified by HPLC/MS/MS in blood, urine, and feces collected over 24 h. The concentrations of serum curcuminoids were always below 4 nmol/L and those of glucuronides 10-fold less. Encapsulation delayed and increased curcuminoid absorption as compared to the free ingredient. Serum and urinary concentrations of ferulic and vanillic acid were between 2- and 1000-fold higher than those of curcuminoids, with ECBB eliciting the highest amounts. Fecal curcuminoids were 6-fold more abundant after ECB than FCB, while phenolic acids after ECBB quadruplicated those after ECB. Curcuminoid encapsulation increased their bioavailability from enriched bread, probably preventing their biotransformation, with combined compounds slightly reducing this effect. Phenolic acids are the major metabolites of curcuminoids and may contribute to their biological properties. 相似文献
477.
Canedoli Claudia Ficetola Gentile Francesco Corengia Davide Tognini Paola Ferrario Andrea Padoa-Schioppa Emilio 《Landscape Ecology》2022,37(1):347-365
Landscape Ecology - A landscape is defined as a “system of ecosystems” and this is a model in which karst areas can easily be integrated. In karst areas, much of the connectivity... 相似文献
478.
Gluten proteins are the basis of the rheological properties of wheat derived products, such as bread and pasta. Their particular amino acidic composition (high proline and glutamine content) is responsible for the poor gluten digestibility. Some of the high molecular weight peptides that are generated in the gastrointestinal tract are involved in an autoimmune entheropathy called celiac disease. In this work we compared the amount of peptides containing sequences involved in adaptive and immune responses, which were produced after simulated gastrointestinal digestion of prolamins extracted from different durum wheat varieties and in-bred lines. Peptides containing sequences involved in celiac disease were quantified using an isotopically labeled peptide as internal standard. The results demonstrated a very high variability in the amount of pathogenic peptides produced by different lines, showing a strong contribution of the genetic component. At the same time, the variability in total protein and gluten content was lower; the weak correlation between pathogenic peptides and the amount of gluten proteins gives rise to the possibility of a varietal selection aimed to maintain good rheological properties, but simultaneously reducing the exposure to peptides eliciting an immunological response in celiac predisposed subjects. These varieties might be useful for celiac disease prevention. 相似文献
479.
Ilaria Finore Paola Di Donato Vincenza Mastascusa Barbara Nicolaus Annarita Poli 《Marine drugs》2014,12(5):3005-3024
In the last decades, research has focused on the capabilities of microbes to secrete exopolysaccharides (EPS), because these polymers differ from the commercial ones derived essentially from plants or algae in their numerous valuable qualities. These biopolymers have emerged as new polymeric materials with novel and unique physical characteristics that have found extensive applications. In marine microorganisms the produced EPS provide an instrument to survive in adverse conditions: They are found to envelope the cells by allowing the entrapment of nutrients or the adhesion to solid substrates. Even if the processes of synthesis and release of exopolysaccharides request high-energy investments for the bacterium, these biopolymers permit resistance under extreme environmental conditions. Marine bacteria like Bacillus, Halomonas, Planococcus, Enterobacter, Alteromonas, Pseudoalteromonas, Vibrio, Rhodococcus, Zoogloea but also Archaea as Haloferax and Thermococcus are here described as EPS producers underlining biopolymer hyperproduction, related fermentation strategies including the effects of the chemical composition of the media, the physical parameters of the growth conditions and the genetic and predicted experimental design tools. 相似文献
480.