Development of tools for studying Olea europaea: Pseudomonas savastanoi interaction

Poster apresentado no 13th Congress of the Federation of European Societies of Plant Physiology, em 2002, Hersonissos, Creta, GréciaPortugal is one of the main world olive oil producers. Consequently, the culture of olive trees is of considerable importance for our country. In order to maintain and improve our varieties, responses to environmental stresses and pests, which can seriously affect productivity, must be studied, and clones more adapted to challenge stress conditions must be found. One problem that seriously affects Portuguese olive orchards' is olive knot, a disease caused by Pseudomonas savastanoi (Pseudomonas syringae pv savastanoi) which, causing tumours in the stems and leaves of the trees, drastically reduces the production of fruits. Some varieties, like Galega Vulgar, are know to be resistant to the disease, while others, like Cordovil de Serpa, variety are know to be susceptible. With the objective of developing an in vitro system of eliciation of Olea europaea with an avirulent strain of Pseudomonas savastanoi, we have initiated suspension cell cultures of from calli of the variety Galega Vulgar. Cells in middle exponential growth phase were incubated with a suspension of P. savastanoi.Hypersensitive response was studied using XTT (sodium,3’-(1-[phenylamino-carbonyl]-3,4-tetrazolium)-bis(4-methoxy-6-nitro) benzene-sulfonic acid) by the quantification of the perhydroxyl / superoxide (H2O./O2-) radical acid-base pair associated to the oxidative burst, during the time course of elicitation. The results showed the existence of two bursts (100 and 300 min after eliciation), which are characteristic of the HR that occurs in the incompatible interactions). By screening an elicited O. europaea cDNA library a clone encoding phenylalanine ammonia lyase (PAL) was obtained. The coding region was used as probe for evaluate Pal expression levels. The results will be discussed by comparing to variation of PAL activity, during the time course of elicitation.Fundação para a Ciência e a Tecnologia (FCT) – grant ref. SFRH/BD/6654/2001, Programa Operacional “Ciência, Tecnologia, Inovação” (POCTI) - POCTI / AGR / 36239 / 99-00

The hypersensitive response of Olea europaea L. elicitates by Pseudomonas savastanoi

Poster apresentado no 14th Federation of European Societies for Plant Biology Congress, Cracóvia, Polónia.In plants, the Hypersensitive Response (HR) is an early defense mechanism that is elicited by the recognition of an incompatible pathogen, with the objective of restricting its spread. One of the earliest events in the HR is the rapid and significant increase in Reactive Oxygen Species (ROS) levels in the cells. This Oxidative Burst has various consequences, in particular the induction of the synthesis of secondary metabolites like phythoalexins (compounds with anti-microbial activity) and lignin (to reinforce the cell wall), and the triggering of a programmed cell death. We used a previously established in vitro elicitation system to study the interaction between Olea europaea L. and its pathogen Pseudomonas savastanoi, responsible for the olive knot, a disease that drastically affects olive oil production in Portugal. Material and Methods: The in vitro elicitation system used in this work was composed of suspension cell cultures of the resistant Olea europaea variety Galega Vulgar and by an avirulent strain of the pathogen Pseudomonas savastanoi. ROS detection was performed using a modification of the method described by Parsons et al. (1999), lipid peroxidation was measured using the TBA test and phenylalanine ammonia lyase (PAL) activity was evaluated by the quantification of trans-cinnamic acid determined spectrophotometrically at 290 nm. Results and Conclusions: Evaluation of ROS levels show a significant increase in production by the elicitated O. europaea cells, with a pattern typical of incompatible interactions, indicating that the Galega Vulgar variety is in fact resistant to the pathogen. This OB leads to significant cellular damage, illustrated by increased levels of lipid peroxidation. PAL activity also increased in elicitated cells, pointing toward changes in the phenylpropanoid pathway and, therefore, in the production of secondary metabolites. Quantification of lignin and of the total soluble phenolics allowed us to assess these changes. In order to evaluate the programmed cell death of the challenged cells, the T.U.N.E.L. assay was carried out during the time course of elicitation. References: Parsons HL, Yip YHJ, Vanlerberghe GC. 1999. Increased Respiratory Restriction during Phosphate Limited Growth in Transgenic Tobacco Cells Lacking Alternative Oxidase. Plant Physiol 121; 1309-1320. Since the ROS produced in the OB function mainly as an intracellular signal, we studied the effect of Hydrogen peroxide as a signal molecule. Various concentrations of H2O2 were added to suspension cell cultures of O. europaea and PAL activity was measured. The increase in PAL activity when the added concentrations were low indicates that hydrogen peroxide may in fact function as a transduction signal during the HR. Heath RL, Packer L. 1968. Photoperoxidation in isolated chloroplasts. I. Kinetics and stoichiometry of fatty acid peroxidation. Arch Biochem Biophys 125(1); 189-98.Projecto Olea - ref. POCTI/AGR/36239.Fundação para a Ciência e a Tecnologia (FCT) - grant ref. SFRH/BD/6654/2001

Efeito da aplicação de tratamentos pós-colheita na conservação de raízes de mandioca.

O objetivo deste trabalho foi avaliar a eficiência do revestimento com fécula de mandioca ou parafina na conservação da qualidade pós-colheita de raízes de mandioca armazenadas sob condições ambiente por 9 dias. Após a lavagem e sanitização, as raízes foram revestidas com fécula de mandioca na concentração de 5% ou parafina aquecida a 60 oC e acomodadas em bandejas de poliestireno expandido ? EPS (Isopor®) mantidas sob temperatura ambiente. Como controle foram utilizadas raízes sem recobrimento. As análises foram realizadas diariamente, durante 9 dias de armazenamento, sendo avaliada a perda de massa, tempo de cozimento, aparência visual, umidade, pH e acidez titulável. Por meio de identificação visual, observou-se que o escurecimento vascular foi o principal sintoma de deterioração nas mandiocas. Nas raízes que não sofreram qualquer tratamento e naquelas submetidas ao tratamento com revestimento de fécula, os sintomas de deterioração apareceram no terceiro dia de armazenamento, em cerca de 50% das raízes. Nas mandiocas submetidas ao tratamento com revestimento de parafina, os primeiros sintomas internos foram observados no quarto dia de armazenamento, em 33,3% das raízes analisadas. O revestimento com parafina foi responsável também por menor perda de massa e menor tempo de cozimento das raízes ao longo de todo o período de armazenamento. Para a análise de umidade, observaram-se teores variando de 57,9% a 64,7%. Para as análises de pH e acidez titulável verificou-se oscilação nos resultados ao longo do período de armazenamento para os três tratamentos estudados.bitstream/item/31764/1/BPD74.pdfVersão eletrônica. 1ª impressão: 2010

Investigating IoT Middleware Platforms for Smart Application Development

With the growing number of Internet of Things (IoT) devices, the data generated through these devices is also increasing. By 2030, it is been predicted that the number of IoT devices will exceed the number of human beings on earth. This gives rise to the requirement of middleware platform that can manage IoT devices, intelligently store and process gigantic data generated for building smart applications such as Smart Cities, Smart Healthcare, Smart Industry, and others. At present, market is overwhelming with the number of IoT middleware platforms with specific features. This raises one of the most serious and least discussed challenge for application developer to choose suitable platform for their application development. Across the literature, very little attempt is done in classifying or comparing IoT middleware platforms for the applications. This paper categorizes IoT platforms into four categories namely-publicly traded, open source, developer friendly and end-to-end connectivity. Some of the popular middleware platforms in each category are investigated based on general IoT architecture. Comparison of IoT middleware platforms in each category, based on basic, sensing, communication and application development features is presented. This study can be useful for IoT application developers to select the most appropriate platform according to their application requirement

Formatação de dados usando a ferramenta Velocity.

Origem e características; Arquitetura. Funcionamento e esquema de uso. Linguagem VTL. Aplicação Java. Configuração da Velocity. Trecho de código fonte Java exemplificando o uso da ferramenta Velocity. Trecho de template em VTL relativo ao item anterior.bitstream/CNPTIA/9874/1/comuntec20.pdfAcesso em: 29 maio 2008

Estudos para melhoria da arquitetura do gerenciador de conteúdos da Agência de Informação Embrapa.

bitstream/CNPTIA/10059/1/doc32.pdfAcesso em: 29 maio 2008

Estudo de expert system shells para o ambiente de diagnose remota.

Conceitos: sistemas especialistas, Expert Sysyem Shell, Diagnose remota, AppLets, ServLets. Ambiente de diagnose remota e motivação de mudança. Ferramentas estudadas: WebLS. JESS, CLIPS, WebCLIPS, quadros comparativos.bitstream/CNPTIA/9215/1/DOCUMENTO7int.pdfAcesso em: 29 maio 2008