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161.
Ciardullo S Aureli F Coni E Guandalini E Iosi F Raggi A Rufo G Cubadda F 《Journal of agricultural and food chemistry》2008,56(7):2442-2451
The distribution and potential bioaccumulation of dietary arsenic, cadmium, lead, mercury, and selenium in organs and tissues of rainbow trout (Oncorhyncus mykiss Walbaum, 1792), a major aquaculture species, was studied in relation to fish growth over a period of >3 years. Fish were reared under normal farming conditions, that is, fed a standard fish food and exposed to negligible levels of waterborne trace elements. The age-related variations in the content of each trace element in gills, kidney, liver, muscle, and skin were studied through nonparametric regression analysis. A buildup of all elements in all tissues and organs was observed, but due to dilution with growth, the concentrations did not increase, except in a few cases such as cadmium and mercury in liver and kidney. In muscle tissue, the concentrations of mercury, lead, and selenium did not alter significantly with growth, whereas cadmium increased but remained at exceedingly low levels. The concentration of arsenic in muscle tissue peaked at 14 months and then decreased in adult specimens. Arsenic speciation by high-performance liquid chromatography--inductively coupled plasma mass spectrometry revealed that arsenic in muscle was almost exclusively present in the form of nontoxic arsenobetaine. Application of a mercury mass balance model gave predicted concentrations in agreement with measured ones and showed that in farmed rainbow trout the ratio of mercury concentrations in feed and in fish is about 1:1. Therefore, rainbow trout does not approach the limits established for human consumption even when reared with feed at the maximum permitted levels. These findings highlight the low bioaccumulation potential of toxic trace elements such as cadmium, lead, and mercury in rainbow trout following dietary exposure. On the other hand, selenium concentrations in muscle (about 0.2 microg g (-1) of fresh weight) show that rainbow trout may be a good source of this essential element. 相似文献
162.
D'Agostina A Boschin G Resta D Annicchiarico P Arnoldi A 《Journal of agricultural and food chemistry》2008,56(12):4450-4456
The objective of this study was to monitor the changes in isoflavone content in different plant organs (leaves, stems, roots) during the crop growth stage of three cultivars of Lupinus albus (white lupin) under field conditions, taking into account sowing time effects (autumn and early spring) and cultivar effects. Three sampling dates (from late vegetative to late grain growth stages) were evaluated. Seven isoflavones and four flavonoids were identified by LC-ESI-MS analysis. The isoflavone content was higher in leaves than in stems, and it was highest before flowering, whereas it decreased during maturity. Autumn-sown plants showed higher isoflavone content than early spring-sown plants, especially in late vegetative and early reproductive stages. Genistein 7- O-glucoside was the main isoflavone of leaves and stems in the late vegetative stages of early spring sowing, whereas genistein was the main isoflavone under autumn sowing. Variation among cultivars affected only marginally the total isoflavone content. No isoflavones were detected in seeds. 相似文献
163.
164.
Pintore Ilenia Gilardi Giovanna Garibaldi Angelo Gullino Maria Lodovica 《植物病害和植物保护杂志》2018,125(3):297-309
Journal of Plant Diseases and Protection - The efficacy of different fungicides, belonging to different chemical groups, was in vitro and in vivo tested in glasshouse trials against Allophoma... 相似文献
165.
Surface protein components from entomopathogenic nematodes and their symbiotic bacteria: effects on immune responses of the greater wax moth,Galleria mellonella (Lepidoptera: Pyralidae)
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166.
Genotype-by-environment interactions (GEIs) can affect breeding progress because they often complicate the evaluation and
selection of superior genotypes. This drawback can be reduced by gaining insights into GEI processes and genotype adaptation.
Here, we have studied the GEIs over a set of 24 barley genotypes that were grown across six environments (location-by-year
combinations) in Sardinia, Italy. Three groups of genotypes were analysed: barley landraces (LANs), recombinant inbred lines
(RILs), and commercial varieties (VARs). The additive main effects and multiplicative interaction (AMMI) model was used for
data analysis, and results evidenced no significant differences in grain yield averages for the 24 genotypes. However, there
was a relevant GEI for yield mainly between two of the six environments (one characterised by warm pre-anthesis period and
high spring rainfalls, and the other characterised by opposite features) and two groups of genotypes (VAR and LAN). Moreover,
a negative trade-off between yield levels of genotypes was seen when the barley genotypes were grown in the contrasting environments.
Overall, intermediate GEI levels were seen for RILs in comparison to LANs and VARs, and some of the RILs provided valuable
yield levels (e.g. RILs 23 and 52). The results thus show the potential usefulness of LANs as a genetic resource for breeding,
e.g. to obtain genotypes adapted to Mediterranean environments, such as the RILs analysed in this study.
Most of the actual work was carried out when the first author was a PhD student in ‘Agro-meteorology and ecophysiology of
agricultural and forest systems’ and she was affiliated to Dipartimento di Scienze Agronomiche e Genetica Vegetale Agraria,
Università degli Studi di Sassari, Via E. de Nicola, Sassari 07100, Italy. 相似文献
167.
Maria Lodovica Gullino Giovanna Gilardi Mattia Sanna Angelo Garibaldi 《Phytoparasitica》2009,37(5):461-466
Leaf spot of tomato, incited by Pseudomonas syringae pv. syringae, has been reported recently in Italy on grafted and non-grafted tomato plants (scion Cuore di Bue, rootstock Solanum lycopersicum x Solanum hirsutum cv. Beaufort). In some greenhouses, more than 80% of plants were affected, with a marked reduction in yield. This work was
undertaken in order to understand the effect of the number of hours of incubation at high relative humidity (r.h.) and temperature
as well as the effect of the presence of wounds at infection time on the development of leaf spot. A difference in sensitivity
to leaf spot was observed in the various cultivars tested, in terms of severity of P. syringae pv. syringae, with “Cuore di Bue” being the most susceptible of these cultivars. The development of leaf spot is mostly favored by the
presence of wounds, at temperatures between 15 and 20°C. The severity of the disease is lower at 10 and 25°C and very low
at 30°C. Under the most favorable temperature conditions, the presence of wounds is sufficient to allow the development of
the pathogen immediately upon incubation at high r.h. The effect of wounds and the relatively low requirement of hours of
incubation at high r.h. suggest the need for careful management and handling of plants when temperatures range between 15
and 25°C, and particularly within 15 and 20°C. All operations carried out, particularly at transplant and immediately after,
should avoid the creation of wounds. 相似文献
168.
Cludio C. Maretti Adriana R. Leo Ana Paula Prates Eliane Simes Ricardo B.A. Silva Ktia T. Ribeiro Leonardo Geluda Manoel S. Sampaio Fernanda F.C. Marques Anna C. Lobo Luís H. de Lima Leonardo M. Pacheco Warwick A. Manfrinato Antnio Q. Lezama Matheus T.P. Couto Paula M. Pereira Moara M. Giasson Paulo H.M. Carneiro Aldízio L. de Oliveira Filho Bernardo F.A. Brito Maurício S. Pompeu Guilherme F. Dutra Mara C. Nottingham Giovanna Palazzi Fabiana O. Hessel Andr L. Lima Bruna De Vita S. Santos Rodrigo Medeiros Marcelo M. Oliveira Mauro O. Pires Mnica Assad Mariana G. Pereira Marcelo R. Kinouchi Rosana J. Subir 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):44-70
- 相似文献
169.
Stefano Moro Giovanna Jona‐Lasinio Barbara Block Fiorenza Micheli Giulio De Leo Fabrizio Serena Massimiliano Bottaro Umberto Scacco Francesco Ferretti 《Fish and Fisheries》2020,21(2):338-349
Conservation of apex predators is a key challenge both in marine and terrestrial ecosystems. The white shark is a rare but persistent inhabitant of the Mediterranean Sea and it is currently assessed as “critically endangered” in the region. However, the population trends and dynamics of this species in the area are still unknown. Little is known about white shark distribution, habitat use and population abundance trends, aspects that are critical for conservation and management. In this study, we built the most comprehensive database of white shark occurrence records in the region. We collected 773 different records from different sources and used them to characterize the spatial and temporal patterns of abundance of Mediterranean white sharks between 1860 and 2016. We analysed these data by using generalized additive models and used spatially disaggregated information on human population abundance as a proxy of observation effort. Our results suggest a complex trajectory of population change characterized by a historical increase and a more recent reduction (61%, range 58%–72%) since the second half of the 20th century. In particular, analyses reveal a 52% (range 37%–88%) to 96% (range 92%–100%) overall decline in different Mediterranean sectors and a contraction in spatial distribution. Here, we provide the first reconstruction of abundance trends and offer new hypotheses regarding the drivers of change of white sharks in the Mediterranean. Our approach can be broadly applied to data‐poor contexts to reconstruct change and inform the conservation of endangered top predators in the Mediterranean Sea and other intensely used marine regions. 相似文献
170.
Linseisen J Rohrmann S Norat T Gonzalez CA Dorronsoro Iraeta M Morote Gómez P Chirlaque MD Pozo BG Ardanaz E Mattisson I Pettersson U Palmqvist R Van Guelpen B Bingham SA McTaggart A Spencer EA Overvad K Tjønneland A Stripp C Clavel-Chapelon F Kesse E Boeing H Klipstein-Grobusch K Trichopoulou A Vasilopoulou E Bellos G Pala V Masala G Tumino R Sacerdote C Del Pezzo M Bueno-de-Mesquita HB Ocke MC Peeters PH Engeset D Skeie G Slimani N Riboli E 《Public health nutrition》2006,9(4):449-464