Loss of genetic variability in the captive stocks of tambaqui,Colossoma macropomum (Cuvier, 1818), at breeding centres in Brazil,and their divergence from wild populations          下载免费PDF全文

Jonas da Paz Aguiar  Paola Fabiana Fazzi Gomes  Igor Guerreiro Hamoy  Sidney Emanuel Batista dos Santos  Horacio Schneider  Iracilda Sampaio 《Aquaculture Research》2018,49(5):1914-1925

The loss of variability in farmed populations and the risks of interactions with wild populations support the need for the genetic monitoring of species farmed throughout the world. In Brazil, the tambaqui is the most widely farmed native fish species. Despite this, there are no data on the pedigree of the farmed stocks, and the potential for interactions with wild populations in the Amazon basin has raised concerns with regard to the genetic variability of these stocks. The present study analysed sequences of the mitochondrial Control Region and 12 microsatellites to characterize the genetic variability of seven historically important commercial tambaqui breeding centres located in four different regions of Brazil, and compared these sequences with those obtained from individuals collected from a wild population. High levels of genetic diversity were found in the wild population, whereas genetic diversity was reduced in both markers in most captive populations, except for the broodstock located near the Amazon River. High F_ST and D_EST indices were recorded between the wild population and most of the captive stocks analysed. The drastic reduction in genetic diversity found in most captive stocks and the difference between these stocks and the wild population may have been the result of the small size of the founding populations and the absence of breeding management. The renewal of the broodstocks and the application of breeding management techniques are recommended. In the Amazon region, in addition, the use of broodstocks that are genetically very different from local wild populations should be avoided.  相似文献   

Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study          下载免费PDF全文

Angela Boggero  Alberto Basset  Martina Austoni  Enrico Barbone  Luca Bartolozzi  Isabella Bertani  Alessandro Campanaro  Antonella Cattaneo  Fabio Cianferoni  Giuseppe Corriero  Ambrosius Martin Dörr  A. Concetta Elia  Gentile Francesco Ficetola  Lyudmila Kamburska  Gianandrea La Porta  Sara Lauceri  Alessandro Ludovisi  Elda Gaino  Enzo Goretti  Massimo Lorenzoni  Marina Manca  Aldo Marchetto  Giuseppe Morabito  Francesco Nonnis Marzano  Alessandro Oggioni  Cataldo Pierri  Nicoletta Riccardi  Giampaolo Rossetti  Nicola Ungaro  Pietro Volta  Silvia Zaupa  Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852

Allozyme variation in the springtails Allacma fusca and A. gallica (Collembola, Sminthuridae)     

Pietro P. Fanciulli  Antonio Carapelli  Massimo Belloni  Romano Dallai  Francesco Frati 《Pedobiologia》2009,52(5):309-324

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Residues of a Triazole Fungicide in Soil After 4 Years of Application to Sugar Beet     

Luigi Lucini  Paloma Magistrati  Gian Pietro Molinari 《Water, air, and soil pollution》2009,202(1-4):13-18

An experimental study to investigate the potential soil accumulation of the triazole fungicide difenoconazole in soil was carried out in northwestern Italy. The fungicide was applied to sugar beet for 4 years with three applications per year at a rate of 75 g ha^?1 each, according to formulated product recommended use. Soil cores were collected each year before the first application, after each application and at harvest of the crop. The soil samples were then split into 0–10 and 10–40 cm depth layers, extracted and quantitatively analysed by gas chromatography for difenoconazole residues. The study evidenced that difenoconazole residues could be detected in the upper soil layer only, in quantities detectable after several applications (0.14 to 0.32 mg kg^?1 after the third application) which then become undetectable the following year. It can be concluded, therefore, that difenoconazole does not accumulate in soil.  相似文献   

Parameterization of ruminal fibre degradation in low-quality tropical forage using Michaelis–Menten kinetics     

Edenio Detmann  Mrio F. Paulino  Hilrio C. Mantovani  Sebastio de C. Valadares Filho  Cludia B. Sampaio  Marjorrie A. de Souza  Ísis Lazzarini  Kelly S.C. Detmann 《Livestock Science》2009,126(1-3):136-146

This work aimed to parameterize the ruminal degradation of neutral detergent fibre (NDF) from low-quality tropical forage using Michaelis–Menten kinetics. The intake, rumen outflow (L), fractional degradation rate (kd), discrete lag (LAG) and effective degradability (ED) of NDF, and the microbial flow of nitrogenous compounds into the small intestine (Nmic) were assessed in two 5 ×  5 Latin square experiments by using five Holstein × Zebu heifers cannulated in the rumen. The experiments were carried out sequentially and the treatments were formed by increasing the level of supplementation with nitrogenous compounds. A low-quality signal grass (Brachiaria decumbens) hay was used as roughage. The nitrogen supplement was a mixture of urea, ammonium sulfate and albumin, at the ratios of 4.5:0.5:1.0, respectively. The crude protein contents in the diets ranged from 51.9 to 136.3 g/kg of dry matter. The rumen ammonia nitrogen (RAN) concentration was used as an independent variable. The NDF intake, L and Nmic showed a quadratic pattern (P < 0.05) as a function of RAN concentration, and the critical points (maximum responses) were observed with 15.17, 16.28, and 14.52 mg of RAN/dL of rumen fluid, respectively. On the other hand, ED and LAG presented a linear-response-plateau (P < 0.05) according to the RAN concentration, with break points close to 8 mg/dL for ED (maximum estimate) and LAG (minimum estimate). The RAN concentrations to optimize NDF degradation and intake were defined as 8 and 15 mg/dL, respectively. This difference between estimates appears to be due to a better adequacy of the metabolizable protein:metabolizable energy ratio in the animal metabolism, which increases the animal intake even after the rumen NDF degradation has been optimized. This observation was supported by Nmic pattern. An adapted Michaelis–Menten model was applied to the data, where RAN was the independent variable and kd the dependent variable. The relationship between these variables was found to be significant by using the Hanes–Woolf plot (P < 0.01). Based on this model, the rate of NDF degradation as a function of RAN concentration indicates that fibre degradation in the rumen could be considered a second order process. In this context, the RAN concentration of 8 mg/dL was assumed as the limit where zero order (below limit) and first order (above limit) reactions become predominant for NDF degradation in the rumen.  相似文献   

Not in my backyard: effectiveness of outdoor residual spraying from hand‐held sprayers against the mosquito Aedes albopictus in Rome,Italy          下载免费PDF全文

Mattia Manica  Pietro Cobre  Roberto Rosà  Beniamino Caputo 《Pest management science》2017,73(1):138-145

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Removal of Phenolic Compounds from Aqueous Solutions Using Sludge-Based Activated Carbons Prepared by Conventional Heating and Microwave-Assisted Pyrolysis     

Glaydson S. dos Reis  Matthew A. Adebayo  Carlos H. Sampaio  Eder C. Lima  Pascal S. Thue  Irineu A. S. de Brum  Silvio L. P. Dias  Flavio A. Pavan 《Water, air, and soil pollution》2017,228(1):33

Sludge-derived activated carbons (ACs) were prepared by conventional heating and microwave pyrolysis. The ACs were characterized using several analytical and functional techniques and used for removal of six phenolic compounds from aqueous solutions. The adsorbents exhibited similar features and possessed hydrophobic surfaces. The ACs were assigned mesoporous materials, with specific surface areas of up to 641 and 540 m² g^?1 for CAC-500 and MAC-980, respectively. The preliminary results indicated that phenol removal onto the ACs increased in the order: m-cresol?<?phenol?<?o-cresol?<?2-chrorophenol?<?2-nitrophenol?<?hydroquinone. Hydroquinone exhibited the highest adsorption capacity and was chosen to continue the remaining part of the experimental work—kinetic and isothermal studies. The adsorption kinetic and isotherm data were well described by the Avrami fractionary order and Redlich–Peterson models, respectively. The maximum amounts (Q _max) of hydroquinone adsorbed at 25 °C were too high, reaching 1218.3 and 1202.1 mg g^?1 for CAC-500 and MAC-980, respectively. The mechanism of adsorption was proposed in this work, and it was suggested that donor–acceptor complex and π–π interactions play major roles in the adsorption process. The adsorbents were also tested on simulated effluents. The two ACs displayed good efficiency for the treatment of industrial simulated effluents.  相似文献   

Closed cycle subirrigation with low concentration nutrient solution can be used for soilless tomato production in saline conditions     

Francesco Montesano  Angelo Parente  Pietro Santamaria 《Scientia Horticulturae》2010

Closed cycle soilless techniques can be adopted to minimize water and fertilizer losses in greenhouse cultivation. There is a general lack of information regarding the soilless cultivation of vegetables with closed cycle subirrigation techniques, specifically when using saline water. In this study, a trough bench subirrigation system (SUB), with two fertilizer concentrations (“100%”, containing 9.8 mol m⁻³ N-NO₃, 1.6 mol m⁻³ P-H₂PO₄, 8.7 mol m⁻³ K⁺, 2.8 mol m⁻³ Ca⁺, 1.8 mol m⁻³ Mg⁺, 4 mol m⁻³ S-SO₄, and “70%”, containing 70% of the macronutrient concentration) in the nutrient solution (NS), was compared with open cycle drip-irrigation (DRIP with “100%” NS). For all the three treatments, NS was prepared using rain water (0.05 dS m⁻¹) and adding NaCl (1 g L⁻¹), in order to simulate moderate saline irrigation water. The effect of the treatments on tomato (Solanum lycopersicum L.) plant growth, yield, fruit quality, water use efficiency (WUE) and fertilizer consumption was evaluated. Substrate and recirculating NS composition were also studied. Subirrigation, regardless of NS concentration, reduced plant height (by 30 cm), leaf area (by 1411 cm²), total fresh and dry weight (by 429 and 48.5 g plant⁻¹, respectively) but not dry matter percentage of the whole plant, with respect to DRIP. Yield was reduced when plants were subirrigated with the higher concentrated NS, but no differences with open cycle DRIP were recorded when the lower NS concentration was used in SUB. Fruit quality was not affected by irrigation system or NS concentration. The higher WUE was obtained with subirrigation. NaCl accumulated similarly over the crop cycle in recirculating NS of both SUB treatments and in growing substrates of all the three treatments. Higher salt concentration was found in subirrigated substrates, in particular in the upper part of the substrate profile. Fertilizers accumulated in the subirrigated substrates when the higher NS concentration was used, but not when the NS concentration was reduced by 30%. The results of this study indicate that tomato can be grown successfully in a closed cycle subirrigation system, using saline water, by reducing the fertilizer NS concentration normally used with traditional open cycle systems.  相似文献   

Composition and evaluation of a novel web-based decision support system for grape black rot control     

Daniel Molitor  Barbara Augenstein  Laura Mugnai  Pietro Antonello Rinaldi  Jorge Sofia  Bryan Hed  Pierre-Henri Dubuis  Mauro Jermini  Erhard Kührer  Gottfried Bleyer  Lucien Hoffmann  Marco Beyer 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(4):785-798

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Salix rubens and Salix triandra Species as Phytoremediators of Soil Contaminated with Petroleum-Derived Hydrocarbons     

Ana Cristina Borba da Cunha  Sydney Sabedot  Carlos Hoffmann Sampaio  Claudete Gindri Ramos  Alexandre Rodrigues da Silva 《Water, air, and soil pollution》2012,223(8):4723-4731

The petroleum industry activities provide potential risks to the environment because they can contaminate ecosystems with different organic compounds in the production chain. Several accidents with transport and handling of petroleum and related products occurred in urban areas with harmful effects to the quality of life and economy. In the 1990s, bioremediation and phytoremediation technologies as economically feasible alternatives to repair the environmental damage were developed. In this study, the potential of the willows Salix rubens and Salix triandra were evaluated with regard to the phytoremediation of soils contaminated with petroleum-derived hydrocarbons (total hydrocarbons and polycyclic aromatic hydrocarbons (PAHs)). The PAHs were quantified by extraction from soils and plants using dichloromethane under ultrasonication. The HPLC analysis was performed with GC/MSD equipment. The total hydrocarbons present in uncontaminated soil were quantified by the sum of animal/vegetable oils and greases and mineral oils and greases according to Standard Methods 5520 (1997). The two willows species S. rubens and S. triandra were resistant during the project development. In the contaminated soil, in which both species were planted, the total hydrocarbons concentration was reduced near 98?%. The PAHs content was remarkably reduced as well. Pyrene showed an initial concentration of 23.06???g?kg^?1, decreasing in most cases to 0.1???g?kg^?1 or to undetectable levels. Chrysene decreased from 126.27???g?kg^?1 to undetectable levels. Benzo[k]fluoranthene and benzo[a]pyrene concentrations had also showed a decrease from 28.44 and 3.82???g?kg^?1, respectively, to undetectable levels.  相似文献