[Truncated abstract] A range of biotic and abiotic stresses increase levels of reactive oxygen species (ROS) in plants due to perturbations of chloroplast and mitochondrial metabolism and the generation of ROS in defence responses. The polyunsaturated fatty acids of membrane lipids are susceptible to ROS induced peroxidation yielding various aldehydes, alkenals and hydroxyalkenals including the cytotoxic compound 4-hydroxy- 2-nonenal (HNE). HNE has the potential to cause substantial oxidative damage in cells via its reactivity with sulfhydryl groups of cysteine (Cys) and lipoic acid, the imidazole group of histidine (His) and the ?-amino group of lysine (Lys) protein residues. Analysis of the components of the plant respiratory electron transport chain to HNE revealed a particular susceptibility to inhibition of activity of the alternative oxidase (Aox). Incubation with HNE prevented dimerisation of Aox protein, suggesting that one site of modification was the conserved cysteine residue involved in dimerisation and activation of this enzyme (Cys1). However, a naturally occurring isoform of Aox lacking Cys1 and unable to dimerise, LeAox1b from tomato, was equally sensitive to HNE inhibition, showing that other amino acid residues in Aox also interact with HNE and are likely responsible for inactivation of the enzyme. ... The broader impact of HNE on the whole Arabidopsis mitochondrial proteome was examined by use of various 2-dimensional gel separation techniques coupled with use of HNE-adduct antibodies. 32 proteins involved in a number of mitochondrial functions were found to be susceptible to modification by HNE, including components of the electron transport chain, the TCA cycle, as well as proteins involved amino acid metabolism and stress-responses. Implications of modification of these proteins by HNE are discussed. As HNE is produced in vivo during oxidative stress, the profile of mitochondrial targets of HNE was examined from Arabidopsis cell cultures exposed to various oxidative stress inducers. Menadione and hydrogen peroxide induced oxidative stress throughout the cell, while antimycin A initiated a mitochondrial targeted stress. A differential profile of mitochondrial proteins was observed to be modified by HNE in the various treatments. These results also showed that induction of stress within a whole cell can impact lipid peroxidation within the mitochondria. Overall, this work showed the presence and production of HNE in plant cells, and that HNE, both exogenous and endogenous, has the ability to modify a specific subset of mitochondrial proteins. In several cases this HNE modification was shown to have functional or structural consequences.

Thesis (Ph.D.)--University of Western Australia, 2007.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 199-213). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 199-213). Also available on the Internet.

No description available.

Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Ribosome inactivating proteins (RIPs) are currently classified as rRNA N-glycosidases, but also have polynucleotide: adenosine glycosidase activity. RIPs are believed to have anti-viral and anti-fungal properties, but the exact mechanism of these proteins still need to be elucidated.The mechanism of resistance however, appears to be independent of the pathogen. For resistance the RIP terminates virus infected plant cells and stops the reproduction and spread of the virus. Transgenic plants containing RIPs should thus be resistant to a wide range of viruses. The ultimate goal of the larger project of which this forms part is the development of virus resistant plants. To monitor the expression of a RIP in a transgenic plant a detection method had to be developed. Antibody detection of the RIP was decided upon as the most cost effective method. The RIP, Dianthin 30 from Dianthus caryophyllus (carnation), was used and expressed in bacterial and insect expression systems. The bacterial expression experiments were done using the pET expression system in BL21(DE3)pLysS cells. The expression in this system yielded recombinant protein at a very low concentration. Expression experiments were also performed in insect tissue culture with the baculovirus vector BAC-TO-BAC™.With this system the expression was also too low to be used for the production of antibodies. A Dianthin 30 specific peptide was then designed and then produced by Bio-Synthesis. This peptide was then used to raise antibodies to detect Dianthin 30. These antibodies were tested on Dianthus caryophyllus proteins. To establish if this detection method was effective to monitor the expression in plants, tobacco plants were transformed with Agrobacterium tumefaciens containing Dianthin 30 in the pART27 plant expression vector. The putative transformed plants were analysed with peR and Southern blots. / AFRIKAANSE OPSOMMING: Tans word Ribosomale-inaktiverende proteïene (RIPs) geklassifiseer as rRNA N-glikosidase wat ook polinukleotied: adenosien glikosidase aktiwiteit bevat. Daar word geglo dat RIPs anti-virale en anti-fungus eienskappe bevat, maar die meganisme van beskerming word nog nie ten volle verstaan nie. Dit is wel bewys dat die meganisme van weerstand onafhanklik is van die patogeen. Virus geinfekteerde plantselle word deur die RIP gedood om die voortplanting en verspreiding te bekamp en sodoende word weerstand bewerkstellig. Transgeniese plante wat dan 'n RIP bevat sal dus weerstandbiedend wees teen 'n wye spektrum virusse. Die hoofdoel van die breër projek, waarvan die projek deel uitmaak: is die ontwikkeling van virusbestande plante. Om die uitdrukking van die RIP in die transgeniese plante te kontroleer, moes 'n deteksie metode ontwikkel word. Die mees koste effektiewe deteksie metode is met teenliggame. Die RIP, Dianthin 30 from Dianthus caryophyllus (angelier) was gebruik vir uitdrukking in bakteriele- en insekweefselkultuur. Die bakteriele uitdrukkingseksperimente was gedoen met die pET uitdrukkings sisteem III BL21(DE3)pLysS selle. Die uitdrukking in die sisteem het slegs rekombinante proteïene gelewer in uiters lae konsentrasies. Uitdrukkingseksperimente was ook gedoen in insekweefselkultuur met die baculovirus vektor BAC-To- BACTM. Met die sisteem was die uitdrukking ook veels te laag om bruikbaar te wees vir die produksie van teenliggame. Daar is toe 'n peptied ontwerp wat Dianthin 30 kan verteenwoordig vir die produksie van teenliggame. Die teenliggame is getoets teen Dianthus caryophyllus proteïene. Om vas te stel of die deteksiemetode wel die uitdrukking van Dianthin 30 sal kan monitor, is tabak ook getransformeer met Dianthin 30. Die transformasies is gedoen met die hulp van Agrobacterium tumefaciens en die pART27 plant uitdrukkings vektor. Die plante is getoets met die polimerase ketting reaksie en Southern klad tegnieke.

Resumo: Este trabalho aborda o problema de identificação dos efeitos causados por eventuais falhas no abastecimento de certos materiais ou equipamentos na linha de montagem de aeronaves. Tal problema consiste em avaliar se o atraso na disponibilidade de um determinado material pode ser absorvido pela flexibilidade existente na rede de atividades da produção. Dessa forma, foi desenvolvido um sistema de apoio à decisão para o planejamento e controle da produção, utilizando simulação de eventos discretos para avaliar se o sincronismo entre os elos da cadeia produtiva está se comportando a contento e, em caso negativo, disponibilizar informações para as correções necessárias. A grande dificuldade na modelagem do sistema está na necessidade de integração de uma complexa cadeia de suprimentos a uma grande rede de atividades necessárias à manufatura das aeronaves. Apesar da complexidade, o sistema criado é capaz de identificar antecipadamente o impacto causado na montagem pelos insumos atrasados, além de prover uma visão de quais materiais, e respectivos fornecedores, apresentam um atraso que não pode ser absorvido pelo sistema, o que facilitaria o trabalho dos gestores da cadeia de suprimentos para aumentar a robustez do sistema. / Abstract: This work approaches the effects identification of problems caused by eventual fails in the provisioning of material or equipments in one assembly line of aircrafts. Such problem consists in evaluating if a delay in the availability of a material can be absorbed by the flexibility in the activities network of the production. This way, a decision support system was developed to support the planning and control of the production, using systems simulation, to evaluate if the synchronism among the links of the productive chain is behaving as necessary; in negative case, the system must to provide information for manager's action. The great difficulty to produce a model of this system is about the necessary integration of a complex supply chain to a big activities network associate to aircrafts manufacture. In spite of that complexity, the system developed is able to identify the impact caused in the assembly line by each late input, providing a vision of which materials, and respective suppliers, have a delay that cannot be absorbed by the production line. So, this research looks for facilitate the manager works in to increase the system robustness. / Orientador: Edgard Dias Batista Junior / Coorientador: Fernando Augusto da Silva Marins / Banca: José Antonio Perrella Balestieri / Banca: José Arnaldo Barra Montevechi / Mestre

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-14T16:00:03Z No. of bitstreams: 1 Kesia Ferreira Alves.pdf: 466143 bytes, checksum: 66630edcc98b43dfb320ee8189581aa0 (MD5) / Made available in DSpace on 2017-03-14T16:00:03Z (GMT). No. of bitstreams: 1 Kesia Ferreira Alves.pdf: 466143 bytes, checksum: 66630edcc98b43dfb320ee8189581aa0 (MD5) Previous issue date: 2008-02-28 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Anthracnose is considered an important disease of bell pepper (Capsicum annuum L.) in the state of Pernambuco and in various parts of the world, causing significant losses for fruit commercialization. Actions directed to preventive measures such as alternative control, are of great importance through the exploration of secondary compounds present in medicinal plants with antimicrobial activity. This study aimed to, assess the efficiency of crude extracts in the control of anthracnose in bell pepper, and analyze the control stability of promising treatments in relation to different extract, inoculum, temperature and pathogen isolates concentrations. In preliminary selection, 16 plant species were used in order to obtain aqueous and hidroalcoólico extracts. The aqueous extracts of garlic (Allium sativum L.), Mallow (Malva sp.), and ginger (Zingiber officinale Roscoe.) showed greater than 97% reductions in disease severity levels. The greatest value of CL75 was found for the garlic extract (3.5%), while the lowest value of CL75 was verified with the application of the ginger extract (2.1%). The lowest rate of efficiency reduction of the anthracnose control (TRE) with the pathogen inoculum increase occurred with garlic extract. With regard to different C. gloeosporioides isolates, significant interaction was found between the different extracts and isolates of the pathogen. The plant extracts were effective in controlling the disease in temperatures of 20, 25 and 30 ° C, while temperatures in the 10, 15and 35 ° C there was no disease. There were no differences in the efficiencies of garlic and ginger extracts, while the extract of hollyhock had the lower efficiency at 20 ° C, differing from the other temperatures, and other extracts at this temperature. The results obtained in this study indicate the great potential for use of the garlic extract (6%) in anthracnose control of bell pepper, considering its stability in different situations. / A antracnose é considerada uma importante doença do pimentão (Capsicum annuum L.) no Estado de Pernambuco e em várias partes do mundo, causando perdas significativas à produção de frutos para comercialização. Ações voltadas para medidas preventivas como o controle alternativo, são de grande relevância por meio da exploração de compostos secundários presentes em plantas medicinais com atividade antimicrobiana. O presente trabalho teve por objetivo, avaliar a eficiência de extratos vegetais brutos no controle da antracnose em pimentão, bem como analisar a estabilidade do controle dos tratamentos promissores em relação a.diferentes concentrações dos extratos, concentrações do inoculo e isolados do patógeno e, temperaturas. Na seleção preliminar foram utilizadas 16 espécies vegetais para obtenção de extratos aquosos e etanólicos. Os extratos aquosos de alho (Allium sativum L.), malva (Malva sp.) e gengibre (Zingiber officinale Roscoe.) propiciaram reduções superiores a 97% nos níveis de severidade. O maior valor de CL75 foi constatado para o extrato de alho (3,5%), enquanto o menor valor de CL75 foi verificado com a aplicação de extrato de gengibre (2,1%). A menor taxa de redução da eficiência do controle (TRE) da antracnose com o incremento do inóculo do patógeno ocorreu no extrato de alho. Com relação a diferentes isolados de C. gloeosporioides, foi constatada interação significativa entre os tipos de extratos e os isolados do patógeno. Os extratos vegetais foram eficientes no controle da doença nas temperaturas de 20, 25 e 30 oC, enquanto nas temperaturas 10, 15 e 35 °C não houve doença. Não houve diferenças nas eficiências dos extratos de alho e gengibre, enquanto o extrato de malva apresentou a menor eficiência a 20 oC, diferindo das outras temperaturas, bem como dos demais extratos nessa temperatura. Os resultados obtidos nesse estudo indicam o grande potencial de utilização do extrato de alho a 6% no controle da antracnose em pimentão, considerando sua estabilidade em diferentes situações.

[Truncated abstract] Weeds are a major limitation to agricultural and horticultural production and the main method of control is the use of herbicides. In addition to the resulting chemical pollution of the environment, the wide spread and continues use of herbicides have resulted in many weeds developing resistance to commonly used herbicides. This study investigated the potential of using green manures as a cultural method of control of weed invasion in agricultural fields. To understand the general mechanisms involved in the suppression of seed germination in green manure amended soils, seeds of crop species with little or no dormancy requirements were used in certain studies. Lettuce (Lactuca sativa) and cress (Lepidium sativum) seeds were sown to a sandy soil amended with green manures of lupin (Lupinus angustifolius), Brassica juncea, or oats (Avena sativa) to determine if the amendments affected seed germination and/or decay. It was hypothesised that the addition of plant material would increase the microbial activity of the soil thereby increasing seed decay, under laboratory and greenhouse conditions. Initial experiments used lettuce, cress and lupin seeds. Lettuce and cress are commonly used as standard test species for seed viability studies. Subsequent experiments used seeds of annual ryegrass (Lolium rigidum), silver grass (Vulpia bromoides), wild radish (Raphanus raphanistrum) and wild oat (Avena fatua) as these weed species are commonly found throughout agricultural regions in Western Australia. Amending the soil with lupin or Brassica green manure was established as treatments capable of developing environments suppressive to seed germination. Lupin residues as green manure showed the strongest inhibition of seed germination and seed decay. The decay of certain seeds was enhanced with changes to soil microbial activity, dissolved organic carbon and carbon and nitrogen amounts in lupin amended soil. Seeds of weed species were decayed in lupin amended soil, but showed varied degree of decay. Annual ryegrass and silver grass were severely decayed and wild oat and wild radish were less decayed, in lupin amended soil.

O objetivo desse trabalho foi quantificar e caracterizar danos pós-colheita em pêssegos comercializados na Companhia de Entrepostos e Armazéns Gerais de São Paulo - CEAGESP e testar produtos sanificantes no controle de podridão parda (Monilinia fructicola) e podridão mole (Rhizopus spp.). Para tanto, foram realizadas vinte avaliações semanais, entre as safras de 2003 e 2004, amostrando-se 1% do total de caixas de pêssegos em cinco permissionários que comercializam esta fruta. As amostragens foram estratificadas por variedade, calibre e produtor. Em todos os frutos de cada amostra foram quantificados os danos abióticos e as doenças pré e póscolheita. Os patógenos Monilinia fructicola e Rhizopus spp. foram cultivados em meio de cultura para realização dos experimentos de controle in vitro e in vivo utilizando cloreto de benzalcônio, dióxido de cloro, Ecolife40® e hipoclorito de cálcio, realizados de forma curativa e preventiva, além do gás ozônio aplicado somente curativamente. A incidência média de frutos danificados foi de 42% em 2003 e 32% em 2004, sendo subdivididos em injúrias mecânicas pré-colheita 18 e 12% em 2003 e 2004, respectivamente, e pós-colheita 12% em 2003 e 13% em 2004; doenças pré-colheita 3 e 1% em 2003 e 2004, respectivamente, e pós-colheita 4% em 2003 e 2% em 2004. O fungo do gênero Cladosporium sp. foi o patógeno que mais ocorreu nas safras avaliadas com 30% em 2003 e 28% em 2004. Injúria mecânica foi o tipo de dano póscolheita mais freqüente em pêssegos. Pêssegos da variedade Aurora foram os mais sensíveis às doenças pós-colheita. Nos testes in vitro cloreto de benzalcônio e Ecolife40®, ambos na concentração de 1000 ppm, inibiram totalmente o crescimento da M. fructicola. Nenhum dos produtos testados foi eficiente no controle de Rhizopus spp. in vitro. Nos testes in vivo, somente o cloreto de benzalcônio na concentração de 2 mL. L-1 e Ecolife40® a 3 mL. L-1, quando aplicados nos pêssegos de forma preventiva, reduziram significativamente a podridão parda em relação à testemunha, em frutos sem ferimento. O cloreto de benzalcônio inibiu a infecção de Monilinia fructicola em todas as concentrações utilizadas, quando aplicado de forma curativa em pêssegos sem ferimento. Hipoclorito de cálcio a 0,1, 0,2 e 0,3 g. L-1 e dióxido de cloro a 2 e 3 mL. L-1 também apresentaram inibição no crescimento de Monilinia fructicola nos testes curativos e inoculados sem ferimentos. Nenhum produto aplicado de forma curativa foi significativamente eficiente para impedir o desenvolvimento da podridão parda, quando a inoculação do fungo foi realizada sobre ferimentos no fruto. Nos experimentos, in vivo, realizados com Rhizopus spp. nenhum dos produtos e formas de tratamentos testados foram eficientes. O gás ozônio não foi eficiente, na concentração de 0,1 ppm, no controle de podridões parda e mole em pêssegos. / The purposes of this study were to quantify and characterize postharvest damages in peaches commercialized at the Companhia de Entrepostos e Armazéns Gerais de Sao Paulo ? CEAGESP, Brazil, as well as to evaluate the effectiveness of sanitizing products in controlling brown rot (Monilinia fructicola) and soft rot (Rhizopus spp.). Twenty weekly evaluations were carried out in 2003 and 2004 and 1% of all peach boxes from five concessionaires was sampled. Samples were stratified according to cultivar, caliber and grower. Every fruit in each sample was assessed as to abiotic damages and pre and postharvest diseases. The pathogens Monilinia fructicola and Rhizopus spp. were grown in culture medium to enable the conduction of the in vitro and in vivo experiments with benzalkonium chloride, chlorine dioxide, Ecolife40® and calcium hypochlorite used curatively and preventively, and ozone gas used only curatively. Average incidences of damaged fruits were 42% and 32% in 2003 and 2004, respectively, involving 18% and 12% pre harvest mechanical injuries, 12% and 13% postharvest injuries, 3% and 1% pre harvest diseases and 4% and 2% postharvest diseases, in 2003 and 2004, respectively. The fungus Cladosporium sp. was the most prevalent pathogen (30% in 2003 and 28% in 2004) in the periods evaluated. Postharvest mechanical injuries were the most common damages in peaches. Peaches cv. Aurora were the most susceptible to postharvest diseases. Benzalkonium chloride and Ecolife40®, both at 1000 ppm, completely inhibited the growth of M. fructicola in in vitro experiments. None of the products tested in this study was effective in the in vitro control of Rhizopus spp. Only the in vivo preventive treatment with benzalkonium chloride at 2 mL. L-1 and Ecolife40® at 3 mL. L-1 promoted significant reduction in brown rot in non-injured peaches when compared to control fruits. The curative use of benzalkonium chloride at all concentrations tested inhibited the infection by Monilinia fructicola in non-injured peaches. The curative application of calcium hypochlorite at 0,1; 0,2 and 0,3 g. L-1 and chlorine dioxide at 2,0 and 3,0 mL. L-1 also inhibited the growth of Monilinia fructicola in non-injured peaches. None of the products tested in curative treatments was significantly effective in preventing the development of brown rot when the fungus was inoculated on injured fruits. None of the products tested was effective in the in vivo control of Rhizopus spp. Ozone gas at 0,1 ppm was not effective in controlling brown rot and soft rot in peaches.