Application of artificial photoperiod in fish: a factor that increases susceptibility to infectious diseases?     

Valenzuela A  Campos V  Yañez F  Alveal K  Gutiérrez P  Rivas M  Contreras N  Klempau A  Fernandez I  Oyarzun C 《Fish physiology and biochemistry》2012,38(4):943-950

This paper describes and evaluates the mortality associated with the potential stressor effect induced by application of artificial photoperiods in rainbow trout (Oncorhynchus mykiss). After application of artificial photoperiods, high mortalities of trout subjected to this management were recorded (36% in LD 14:10 and 25% in LD 24:0) as compared to controls (7%). The recorded signology related to diseased trout included darkening, lethargy and erratic swimming. Among the morphological changes, skin lesions and ulcerative-type necrosis could be observed. Blood tests, histopathology and isolation of pathogens identified as Flavobacterium psychrophilum, associated with Aeromonas, Pseudomonas and Saprolegnia sp., were performed. The application of artificial photoperiods suggests that fish may be more susceptible to opportunistic diseases; thus, it is advisable to emphasize preventive measures in fish subjected to this management.  相似文献   

Environmental-friendly farming in Switzerland is not hornwort-friendly     

Irene Bisang  Ariel Bergamini  Luc Lienhard   《Biological conservation》2009,142(10):2104-2113

Traditionally managed arable fields host a specialised flora adapted to regular disturbance through tillage. Agricultural intensification during the 20th century resulted in a pronounced biodiversity decline in European agroecosystems. Anthoceros agrestis and Phaeoceros carolinianus, both largely confined to cultivated land in Central Europe and the only representatives of hornworts in northern Switzerland, are examples of species that decreased in Central Europe during the last century. A repeated survey of 28 arable fields in the Swiss Plateau from 1989 to 1995 demonstrated that crop type and associated farming routines were critical in determining hornwort occurrences. During the 10 years following the completion of this survey, agri-environment schemes were introduced aiming at a more environmental-friendly agricultural production. We re-investigated the selected sites in 2005–2007 to examine whether these programmes favoured hornworts. We found a significant decrease of untilled autumn stubble-fields, which accounted for a decline of hornworts. High relative summer air humidity positively affected hornwort occurrence. Gametophytic populations of both taxa regenerated from the persistent diaspore bank after years of unfavourable conditions. To ensure the long-term persistence of hornworts in the Swiss Plateau, we recommend three alternative modifications of current Swiss agri-environment schemes to be implemented in cereal fields with known hornwort occurrences: (1) Tailored conservation headlands, (2) Autumn stubble-fields and (3) Field margin strips sown with arable flora but without crop plants. The proposed practices will promote other typically ephemeral arable bryophytes and seed plants and are likely to be advantageous also for other organisms, such as farmland birds.  相似文献   

Bacillus thuringiensis B1(2015b) is a Gram-Positive Bacteria Able to Degrade Naproxen and Ibuprofen     

Ariel Marchlewicz  Dorota Domaradzka  Urszula Guzik  Danuta Wojcieszyńska 《Water, air, and soil pollution》2016,227(6):197

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The basis for rootstock resilient to Capnodis species: screening for genes encoding δ‐endotoxins from Bacillus thuringiensis     

Galina Gindin  Zvi Mendel  Bella Levitin  Pradeep Kumar  Tal Levi  Preeti Shahi  Vadim Khasdan  Dan Weinthal  Tatiana Kuznetsova  Monica Einav  Ariel Kushmaro  Alex Protasov  Arieh Zaritsky  Eitan Ben‐Dov 《Pest management science》2014,70(8):1283-1290

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An unusual mortality event in Johnstone River snapping turtles Elseya irwini (Johnstone) in Far North Queensland,Australia          下载免费PDF全文

E Ariel  AB Freeman  E Elliott  W Wirth  N Mashkour  J Scott 《Australian veterinary journal》2017,95(10):355-361

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AtCBF1 Overexpression Confers Tolerance to High Light Conditions at Warm Temperatures in Potato Plants     

Leonardo Storani  Carlos E. Hernando  Roberto J. Staneloni  Edmundo Ploschuk  Matias L. Rugnone  Gustavo G. Striker  Jorge J. Casal  Ariel Chernomoretz  Marcelo J. Yanovsky 《American Journal of Potato Research》2015,92(6):619-635

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Effect of Germination and Fermentation Process on the Antioxidant Compounds of Quinoa Seeds     

Ramiro Ariel Carciochi  Leandro Galván-D’Alessandro  Pierre Vandendriessche  Sylvie Chollet 《Plant foods for human nutrition (Dordrecht, Netherlands)》2016,71(4):361-367

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Zebrafish (Danio rerio) as an animal model for bath infection by Flavobacterium psychrophilum     

Ruben Avendaño-Herrera  Isabella Benavides  Jaime A. Espina  Daniela Soto-Comte  Matías Poblete-Morales  Juan A. Valdés  Carmen G. Feijóo  Ariel E. Reyes 《Journal of fish diseases》2020,43(5):561-570

Flavobacterium psychrophilum is the causative agent of bacterial cold-water disease and rainbow trout syndrome in freshwater salmonid fish worldwide, generating injuries and high mortality rates. Despite several studies on this bacterium, the infection mechanism remains unknown due to limitations in the employed animal models. In this work, we propose using zebrafish (Danio rerio) as a model for studying bacterial pathogenicity. To substantiate this proposal, zebrafish infection by F. psychrophilum strain JIP 02/86 was characterized. Zebrafish larvae were infected using the bath method, and morphological changes and innate immune system activation were monitored using transgenic fish. Salmonid-like infection phenotypes were observed in 4.74% of treated larvae, as manifested by fin, muscle and caudal peduncle damage. Symptomatic and dead larvae accounted for 1.35% of all challenged larvae. Interestingly, infected larvae with no infection phenotypes showed stronger innate immune system activation than specimens with phenotypes. A failure of function assay for myeloid factor pu.1 resulted in more infected larvae (up to 43.5%), suggesting that low infection rates by F. psychrophilum would be due to the protective actions of the innate immune system against this bacterium in zebrafish larvae. Our results support the use of zebrafish as an infection model for studying F. psychrophilum. Furthermore, the percentage of infected fish can be modulated by disturbing, to varying extents, the differentiation of myeloid cells. Using this evidence as a starting point, different aspects of the infection mechanism of F. psychrophilum could be studied in vivo.  相似文献   

Whole-tree water balance and indicators for short-term drought stress in non-bearing ‘Barnea’ olives     

Alon Ben-Gal  Dilia Kool  Gerardo E. van Halsema  Ariel Yafe  Ran Erel  Isaac Zipori  Simon Rüger  Yafit Cohen  Arnon Dag 《Agricultural Water Management》2010,98(1):124-133

Drainage-weighing lysimeters allowed monitoring of water balance components of non-bearing olive (Olea europaea cv Barnea) trees over a 3-month period including short-term events of controlled but severe water stress. The objective of the study was to evaluate a variety of soil and plant-based water status and drought stress monitoring methods on the basis of tree-scale evapotranspiration (ET). As the trees entered into and recovered from water stress, meteorological data, actual ET (ET_a), soil water content and changes in leaf turgor pressure were continuously monitored. Additionally, midday measurements of stem water potential, stomatal conductance, canopy temperature, and quantum yield of PSII photochemistry were conducted. Diurnal (dawn to dusk) measurements of all the above were made hourly on days of maximum stress. Shoot elongation rate was measured for periods of stress and recovery. Quantum yield of PSII photochemistry, stomatal conductance, and stem water potential all successfully indicated reductions in whole-tree water consumption beginning at moderate stress levels. These measured parameters fully recovered to the levels of non-stressed trees soon after water application was renewed. Shoot elongation was reduced 25-30% for the 10-day period during and following drought and recovered thereafter to levels of non-stressed trees. Whole-tree ET_a was reduced by as much as 20% even following full recovery of the leaf level parameters, suggesting reduced canopy size and growth due to the stress period. Non-destructive, continuous (turgor pressure) and remotely sensed (canopy temperature) methods showed promising potential for monitoring effects of water stress, in spite of technological and data interpretation challenges requiring further attention.  相似文献   

1-Methylcyclopropene (1-MCP) delays senescence,maintains quality and reduces browning of non-climacteric eggplant (Solanum melongena L.) fruit     

Juan F. Massolo  Analía Concellón  Alicia R. Chaves  Ariel R. Vicente 《Postharvest Biology and Technology》2011,59(1):10-15

Ethylene action can be counteracted by 1-methylcyclopropene (1-MCP), which has been used during postharvest storage to maintain quality. In this work, we evaluated the effect of 1-MCP treatments on eggplant quality and phenolic metabolism during refrigerated storage. Eggplants (cv. Lucía) were harvested at commercial maturity, treated with 1-MCP (1 μL/L, 12 h at 20 °C), stored at 10 °C for 21 d and subsequently held at 20 °C for 2 d. Corresponding controls were stored at 10 °C and then transferred to 20 °C for 2 d. During storage calyx color, damage and chlorophyll content, fruit weight loss and firmness, pulp sugar content, acidity, browning and total phenolics were measured. In addition, polyphenol oxidase (PPO), pyrogallol peroxidase (POD), and phenylalanine ammonia-lyase (PAL) activities were evaluated. Fruit calyxes showed reduced damage and remained greener in 1-MCP treated than in control fruit. 1-MCP treated eggplants showed lower weight loss. Pulp browning was clearly prevented as a consequence of 1-MCP exposure, and this was associated with delayed senescence, lower accumulation of total phenolics and reduced activity of PAL. The activity of the enzymes PPO and POD involved in the oxidation of phenolics compounds was also decreased in 1-MCP treated fruit. Results suggest that 1-MCP treatments delay senescence, prevent browning and are beneficial to complement low temperature storage and maintain quality of non-climacteric eggplant fruit.  相似文献