Optimization of seasonality and mother plant nutrition for vegetative propagation of Pinus pinaster Ait     

Celia Martínez-Alonso  Angelo Kidelman  Isabel Feito  Tania Velasco  Ricardo Alía  Maria Jo?o Gaspar  Juan Majada 《New Forests》2012,43(5-6):651-663

Due to the high economic importance of Pinus pinaster Ait., there is considerable interest in developing, improving and extending the use of its families for mass clonal propagation and in breeding programmes. In the current study, we evaluated shoot growth, rooting ability and mini-cuttings production of P. pinaster in response to nitrogen fertilization and seasons. We compared eight half-sib families of P. pinaster from Asturias and Galicia (Northern Iberian Peninsula), searching for useful parameters and growing conditions to be included in a mass propagation program for clonal family forestry. We fertilized P. pinaster seedling mother plants kept in a greenhouse with three levels of nitrogen: high (HN), medium (MN) and low (LN) to evaluate rooting ability of mini-cuttings. In addition, we evaluated the maximal potential production of rooted mini-cuttings considering nine cycles of propagation over 1?year, also using three levels of nitrogen. The HN treatment significantly influenced the rooting process, with length, area and volume of roots all being positively affected. Spring was the most favourable season for mini-cuttings in the HN treatment. This study provides valuable new information to optimize the clonal propagation protocol for P. pinaster and shows that the mini-cuttings technique has great potential in mass scale cloning, providing high quality sprout production and well-formed new plants.  相似文献   

Recent developments and new structures and look for 2012     

Celia M. Marr 《Equine veterinary journal》2012,44(1):1-1

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Antibody response and viral shedding profile of Egyptian geese (Alopochen aegyptiacus) infected with low pathogenicity H7N1 and H6N8 avian influenza viruses     

Burger CE  Abolnik C  Fosgate GT 《Avian diseases》2012,56(2):341-346

Egyptian geese (Alopochen aegypticus), a duck species endemic to sub-Saharan Africa and occasionally implicated in the transmission of avian influenza viruses (AIV) to farmed ostriches, were experimentally infected with low pathogenicity H7N1 and H6N8 viruses to assess viral shedding and immune profiles. Following the first infection with H7N1 virus, high titers of virus were shed from both the tracheae and cloacae for at least 7 days postinfection, and tracheal shedding lasting until day 14. All detectable shedding from both tracheae and cloacae had ceased within 28 days of infection. Antibody titers peaked at day 7 postinfection, but the initial immune response was short-lived. Birds that received a second challenge with the homologous H7N1 virus mounted a more robust response that lasted beyond 66 days postchallenge, and H7N1 virus was detected, albeit at much lower levels, until day 28 post secondary infection (psi) in the cloaca and beyond day 28 psi in the trachea. Birds that received an initial infection with H7N1 virus were also challenged with H6N8 virus, and because a comparable shedding pattern to the H7N1 challenge group was observed, we concluded that the effect of any nonspecific immunity was negligible.  相似文献   

Effects of insulin-like growth factor-II on the mitogenic and metabolic activities of equine articular cartilage with and without interleukin 1-beta     

Davenport-Goodall CL  Boston RC  Richardson DW 《American journal of veterinary research》2004,65(2):238-244

OBJECTIVE: To investigate the effects of insulin-like growth factor-II (IGF-II) on DNA and glycosaminoglycan (GAG) synthesis and the expression of matrix-related genes in equine articular cartilage explants and chondrocytes, respectively, with and without interleukin 1-beta (IL1-beta). SAMPLE POPULATION: Articular cartilage from 12 adult horses. PROCEDURE: Articular cartilage was incubated in standard media with and without equine IL1-beta (10 ng/mL) containing various concentrations of IGF-II for 72 hours. Synthesis of DNA and GAG was determined by incorporation of thymidine labeled with radioactive hydrogen (3H) and sulfate labeled with radioactive sulfur (35S), respectively. Total GAG content of the explants and spent media was determined by use of the 1,9-dimethylmethylene blue assay. Northern blots of RNA from cultured equine articular cartilage chondrocytes were hybridized with cDNA of major matrix molecules. RESULTS: Insulin-like growth factor-II stimulated DNA and GAG synthesis at concentrations of 25 and 50 ng/mL, respectively. In cartilage explants conditioned with IL1-beta, IGF-II stimulated DNA and GAG synthesis at concentrations of 500 and 50 ng/mL, respectively. Insulin-like growth factor-II had no effect on total GAG content as determined by the 1,9-dimethylmethylene blue assay. No specific effects on steady-state levels of messenger RNAs were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Insulin-like growth factor-II stimulated DNA and GAG synthesis in equine adult cartilage and may have potential application in vivo.  相似文献   

AORTO-CARDIAC FISTULAS IN SEVEN HORSES   总被引：1，自引：0，他引：1  

Celia M.  Marr  BVMS  MVM  PhD  MRCVS  Virginia B.  Reef  DVM  T.J. Brazil  BVSc  Cert. EM  MRCVS  W.P. Thomas  DVM  D.C. Knottenbelt  BVM&S  DVM&S  MRCVS  D.F. Kelly  BVSc  MA  FRCPath  MRCVS  J.R. BAKER  BVSc  Ph  D  MRCVS  Johanna M.  Reimer  VMD  Abby D.  Maxson  VMD  J.S. Crowhurst  BA  B Vet Med  MRCVS 《Veterinary radiology & ultrasound》1998,39(1):22-31

This report describes the history, clinical, electrocardiographic and echocardiographic findings, treatment, outcome, and post-mortem findings in seven horses with aorto-cardiac fistula. Affected horses included 5 stallions, one gelding and one mare; 2 each of the Thoroughbred, Arabian and Standardbred breeds and one Thoroughbred-cross with a mean ± s.d. age of 12 ± 4 years, range 6–18 years. The presenting sings were acute distress (four horses), exercise intolerance (two horses) and the lesion was detected during a routine examination in one horse. Five horses had monomorphic ventricular tachycardia on admission and one other had a history of this arrhythmia. Five horses had a characteristic continuous murmur loudes in the right fourth intercostal space. Echocardiography (six horuses) and/or post-mortem examination (four horses) revealed the horses had aorto-cardiac fistulas arising from the right aortic sinus in all five horses in which the site was recorded. Two horses had ruptured aneurysmall dilatations of the aortic wall at this site. Fistulas extended into the right ventricle in four horses; the right atrium in two horses, the left ventricle in one horse, and five horses had dissecting tracts in the septal myocardium. Horses survived for periods ranging from 24th to 4 years. Aorto-cardiac fistula should be considered in the differential diagnosis for horses presenting with acute distress, bounding arterial pulse, a right-sided continuous murmur and/or monomorphic ventricular tachycardia, particularly in middle-aged or older stallions. Echocardiography is the technique of choice for confirming the diagnosis and demonstrating accompanying cardiac changes.  相似文献   

Accuracy of carrot yield forecasting using proximal hyperspectral and satellite multispectral data     

Suarez  Luz Angelica  Robson  Andrew  McPhee  John  O’Halloran  Julie  van Sprang  Celia 《Precision Agriculture》2020,21(6):1304-1326

Precision Agriculture - Proximal and remote sensors have proved their effectiveness for the estimation of several biophysical and biochemical variables, including yield, in many different crops....  相似文献   

Identification of bacteria in the tracheal swabs of farmed ostriches and their effect on the viability of influenza A virus     

Celia Abolnik  Christine Strydom  Debbie Landman  Rene Pieterse 《Journal of veterinary diagnostic investigation》2021,33(6):1089

Avian influenza surveillance is a requirement for commercial trade in ostrich products, but influenza A viruses (IAVs) have proven difficult to isolate from ostrich tracheal swabs that test positive using molecular methods. We hypothesized that microbes unique to the ostrich trachea propagate in the transport medium after sampling and affect viral viability. We cultured tracheal swabs from 50 ostriches on 4 farms in South Africa, and recovered and identified 13 bacterial, 1 yeast, and 2 fungal species. Dietzia sp. had not been identified previously in the oropharyngeal tract of a bird, to our knowledge. The bacteria were tested for antimicrobial susceptibility, and most aerobic species, except for Streptococcus sp. and Pseudomonas sp., were sensitive to enrofloxacin; all were susceptible to sulfonamide. Virus inhibition experiments determined that ostrich-source Streptococcus sp., Pantoea sp., and Citrobacter freundii produced extracellular metabolites that caused a substantial reduction in the IAV titers of 99.9%. Streptomyces, Corynebacterium, Staphylococcus, Arthrobacter gandavensis, Pseudomonas putida, and Acinetobacter spp. similarly reduced the viability of IAV from 77.6% to 24.1%. Dietzia appeared to have no effect, but Rothia dentocariosa, Rhodotorula spp., and Clostridium spp. slightly increased the viability of IAV by 25.9, 34.9, and 58.5%, respectively.  相似文献   

Voluntary immobility and existential security in a changing climate in the Pacific     

Carol Farbotko  Celia McMichael 《Asia Pacific viewpoint》2019,60(2):148-162

With the expectation of adverse climate change impacts, some (often majority) Indigenous populations of the Pacific are expressing a preference to remain on Indigenous lands for cultural and spiritual reasons. In some cases, Indigenous people express preparedness to die on traditional territory rather than relocate, representing a new type of agency and resistance to dispossession. This is a prominent politics of place of relevance to emerging debates and decision‐making around retreat and relocation. If climate change is experienced by populations as an existential threat to culture, identity and place‐based connections, voluntary immobility can be an important adaptation strategy that helps to strengthen cultural and spiritual resilience among those facing the prospect of a lost homeland. This paper argues that voluntary immobility decisions need ethically robust and culturally appropriate policies and practices, particularly when a site is deemed by external experts to be no longer fit for human settlement. National governments, civil society groups, international organisations and donors will need to: engage in culturally meaningful dialogue with communities about relocation and immobility; respect, protect and fulfil the rights of ‘immobile’ people and those on the move; and confirm that in situ adaptation options have been exhausted.  相似文献   

The suppressive effects of composts used as growth media against <Emphasis Type="Italic">Botrytis cinerea</Emphasis> in cucumber plants     

Guillem Segarra  Eva Casanova  Celia Borrero  Manuel Avilés  Isabel Trillas 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(4):393-402

The incidence/severity of soil-borne plant diseases is often reduced when composts are used as growth media. However, much less information is available about the effects of composts on the development of foliar diseases. Here we studied the suppressive capacity of five composts (from olive marc-cotton gin trash, grape marc, cork, spent mushroom and municipal organic and yard wastes) as growth media against Botrytis cinerea disease in cucumber plants. We also examined the putative correlations of several biotic and abiotic factors involved in disease suppression. The suppressive capacity of the growth media was studied by comparing disease incidence/severity in plants grown in composts with that occurring in plants grown in commercial peats, which are conducive to most soilborne diseases. Correlations were made between the occurrence of disease and leaf nutrient status, as well as electrical conductivity (EC) and microbial activity (measured as β-glucosidase activity) in the growth media. Cucumber plants grown in the peats showed greater severity of B. cinerea during the bioassay than those grown in composts. Mo, Ca and Si content in leaves showed negative correlations with this disease. A negative correlation with disease severity was observed for EC and microbial activity in the growth media. The noticeable reduction in B. cinerea in plants grown in composts was related to the supply of specific chemical elements, a certain degree of salt stress, and the high microbial activity of composts.  相似文献   

Ethyl cellulose polymer microspheres for controlled release of norfluazon     

Pérez-Martínez JI  Morillo E  Maqueda C  Ginés JM 《Pest management science》2001,57(8):688-694

The pesticide norfluazon has been microencapsulated using ethyl cellulose to develop controlled-release formulations that decrease its mobility through the soil and protect it from photodegradation. Ethyl cellulose microspheres loaded with norfluazon were prepared by the solvent-evaporation method. To obtain the microspheres, certain conditions (pesticide/polymer ratio, percentage of emulsifying agent and solvent) were varied. The shape and size of the microspheres obtained were studied by scanning electron microscopy. Other parameters, such as solids recovery, encapsulation efficiency and pesticide loading, were also studied. The release rate of norfluazon from the different microspheres was slower than that of pure norfluazon. In particular, microspheres obtained with o-xylene, which provided the largest diameter, retarded the initial release of the pesticide relative to microspheres obtained with chloroform, or to pure norfluazon. Moreover, the studies showed that the pesticide/polymer ratio controlled the release of norfluazon, which was slower when this ratio was low. Release rates conformed to a generalised kinetic equation for a diffusion-controlled release mechanism, and the time taken for 50% of the active ingredient to be released into water, t50, was calculated.  相似文献