Techn. Universiẗat, Diss., 2001--Braunschweig. / Erscheinungsjahr auf der Haupttitels.: 2001.

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-08-31T16:43:51Z No. of bitstreams: 1 texto completo.pdf: 1571624 bytes, checksum: 532bd28b48be76bfcc011401faf8fee6 (MD5) / Made available in DSpace on 2017-08-31T16:43:51Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1571624 bytes, checksum: 532bd28b48be76bfcc011401faf8fee6 (MD5) Previous issue date: 2017-07-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O cultivo do tomateiro possui relevante importância sócio-econômica na agricultura brasileira. Mesmo diante deste cenário favorável, a tomaticultura é considerada uma atividade de elevado risco econômico e de grande complexidade agronômica. Dentre os principais problemas, destaca-se a requeima, causada pelo oomiceto Phytophthora infestans (Mont.) de Bary. O controle da doença é altamente dependente do uso de agrotóxicos, pois a maioria dos cultivares de tomateiro não são resistentes. Na tentativa de reverter esse quadro, a principal alternativa é a transferência de genes de resistência presentes em acessos de tomateiro conservados em Bancos de Germoplasma. Assim, após oito anos de pesquisas foi selecionado o acesso BGH-2127 (Solanum lycopersicum), como fontes de resistência a requeima, dentre os 870 acessos de tomateiro do Banco de Germoplama de Hortaliças da Universidade Federal de Viçosa (BGH-UFV). Pelo fato da resistência ser quantitativa, torna-se difícil a avaliação e seleção fenotípica de genótipos superiores, feita apenas no campo ou em associação com marcadores moleculares genéticos tipo QTL. Neste contexto, a metodologia da análise proteômica torna-se uma alternativa viável, pois pode fornecer importantes informações e ferramentas para maior entendimento das rotas metabólicas da interação planta-patógeno e assim auxiliar no desenvolvimento de futuras estratégias para o desenvolvimento de cultivares de tomateiro resistentes. Com o auxílio de ferramentas proteômica, os objetivos deste estudo foram: analisar possíveis diferenças entre os proteomas constitutivos de genótipos de tomateiro contrastantes quanto a resistência à requeima; e identificar proteínas frente a infecção do patógeno que possam explicar possíveis mecanismos moleculares de resistência do tomateiro a esta doença. Foram avaliados o acesso BGH-2127 e o cultivar Santa Clara, resistente e suscetível à requeima, respectivamente. Para avaliação do proteoma constitutivo, as proteínas foram extraídas de amostras das folhas dos genótipos sem que tivesse ocorrido a inoculação, apenas comparando a constituição proteica do BGH-2127 e do Santa Clara. Na avaliação à resposta ao patógeno, as plantas foram inoculadas com uma mistura de esporângios de P. infestans, na concentração de 1x10 3 esporângios mL -1 , coletados em regiões da Zona da Mata Mineira, e as proteínas foram extraídas de folhas de cada genótipo inoculado e não inoculado (controle) coletadas nos tempos 0, 2 e 48 horas. Na análise proteômica foi utilizada a técnica da eletroforese bidimensional (2-DE), com a primeira dimensão (focalização isoelétrica) realizada em tiras IPG de 24 cm, pH 3-10, e a segunda dimensão em SDS-PAGE, em gel 12,5%T. Foram obtidos três géis por tratamento, correspondendo a três repetições biológicas. Em seguida, os géis foram revelados por coloração com azul de coomassie coloidal. Posteriormente as imagens dos géis foram digitalizadas usando o equipamento Image Scanner III e analisadas no software ImageMaster 2D Platinum 7.5. Spots com variação de sobreposição acima de 1,5 e ANOVA p<0,05 foram considerados diferencialmente abundantes. Os spots das proteínas diferencialmente abundantes foram identificados em espectrômetro de massas do tipo MALDI-TOF/TOF Ultraflex III. As listas de massas obtidas foram confrontadas contra os bancos de dados de proteínas obtidos do UNIPROT, com auxílio do software MASCOT e os resultados obtidos, validados pelo aplicativo SCAFFOLD com pelo menos 90% de probabilidade. As proteínas identificadas foram categorizadas funcionalmente usando o software Mapman. Uma vez listadas as proteínas diferencialmente abundantes para os genótipos BGH-2127 e Santa Clara foi realizada a construção de uma rede de interação proteína-proteína utilizando o software STRING. Ensaios de PCR em Tempo Real (RT-PCR) foram realizados para confirmar os níveis de abundância de algumas proteínas identificadas. O RNA total foi extraído de amostras de folhas e o cDNA obtido foi quantificado pelo equipamento SpectraMax M5 microplate/cuvette reader. A amplificação dos fragmentos alvo foi realizada utilizando o equipamento StepOneTM Real-Time PCR System e para a quantificação da expressão gênica foi utilizado o software REST. Na avaliação do proteoma constitutivo, 19 proteínas foram identificadas, e estão relacionadas com metabolismo e energia, fotossíntese, estresse e defesa e à transcrição. Aproximadamente 90% destas proteínas foram mais abundantes no cultivar Santa Clara. As proteínas endoquitinase ácida de 26 kDa e ribonuclease T2 foram mais abundantes no BGH-2127. Atividade enzimática confirmou maior abundância de quitinase no acesso BGH-2127 em relação à Santa Clara. Os padrões de expressão avaliados por PCR em tempo real diferiram dos resultados da análise proteômica. Na avaliação da resposta ao patógeno, 56 proteínas diferencialmente abundantes foram identificadas, sendo 39 referentes ao genótipo resistente e 17 ao suscetível. Estas proteínas foram categorizadas em grupos de funções biológicas de energia e metabolismo, fotossíntese, estresse e defesa, transcrição, outras proteínas e não caracterizadas. Para o acesso BGH-2127, proteínas do estresse oxidativo (2-cis peroxirredoxina BAS1 e 2-cis peroxirredoxina) e relacionadas à patogênese da família PR-5 (taumatina) tiveram os níveis de abundancia relativa aumentados nos tempos 0 e 48 horas após a inoculação, respectivamente, e foram consideradas importantes para o mecanismo de defesa deste genótipo. Os padrões de expressão avaliados por PCR em tempo real diferiram dos resultados da análise proteômica. Redes de interações proteína-proteína forneceram importantes informações sobre atividades celulares envolvidas na resistência do BGH-2127 à requeima. Diferenças na abundância das proteínas endoquitinase ácida de 26 kDa e ribonuclease T2 entre os proteomas constitutivos dos genótipos avaliados podem contribuir para o mecanismo de resistência do BGH-2127 à requeima. Proteínas relacionadas ao estresse oxidativo (PR-9) e família taumatina (PR-5) possuem papel importante no mecanismo de defesa do acesso BGH- 2127 resistente a requeima do tomateiro. / Growing tomatoes has significant economic and social importance in brazilian agriculture. Nevertheless, the tomato production is considered an activity of high economic risk and major agronomic complexity. Among the main problems with regard to pests and diseases, there is the late blight, caused by the oomycete Phytophthora infestans (Mont.) de Bary. Disease control is highly dependent on the use of pesticides and there is no resistant cultivars. The main strategy to reverse that one situation is the introgression of resistance genes present in tomato accessions stored in germplasm banks. So, after eight years of research, BGH-2127 access (Solanum lycopersicum) was selected as a source of resistance to late blight, among the 870 tomato accessions of Vegetable Germplasm Bank of the Federal University of Viçosa (BGH-UFV). Due to the resistance to be quantitative it becomes difficult to practice selection of superior genotypes, made only in the field or associated with genetic molecular markers. In this context, the methodology of proteomics becomes viable alternative to provide valuable information and tools to better understanding the different ways of plant-pathogen relationship, thus this methodology can help future proposals genetic strategies to develop resistance cultivars of tomatoes. With the help of proteomic tools, the objectives of this study were: to analyze differences between the constitutive proteomes of tomato genotypes contrasting in resistance to late blight; and identify proteins against infection of the pathogen that may explain possible molecular mechanisms of resistance of tomato to this disease. The BGH-2127 and Santa Clara cultivar, resistant and susceptible to late blight respectively, were evaluated. For the evaluation of the constitutive proteome, proteins were extracted from leaf samples of the genotypes without inoculation, only comparing the protein constitution of BGH-2127 and Santa Clara. In evaluating the response to the pathogen, the plants were inoculated with a mixture of sporangia of P. infestans sporangia at a concentration of 1 x 10 3 sporangia mL −1 from different regions of Zona da Mata. Proteins were extracted from leaves of each genotype inoculated and non-inoculated (control) collected at time 0, 2 and 48 hours. In the proteomic analysis, the two-dimensional electrophoresis technique (2-DE) was used, with the first dimension (isoelectric focusing) performed using a 24-cm strip containing an immobilized pH gradient (IPG) ranging from 3 to 10 and the second dimension was performed on SDS-PAGE 12.5%T. Three gels were obtained by treatment, corresponding to three biological replicates. Then the gels were stained with colloidal coomassie blue. Posteriorly the gels were scanned with the aid of Image Scanner III and analyzed using ImageMaster 2D Platinum 7.0 software. The expression values were considered significant according to the analysis of variance (ANOVA) at p<0.05. Proteins in which the abundance ranged at least 1.5 times were considered to be differentially abundant. Protein identification was performed using the MALDI- TOF/TOF Ultraflex III type mass spectrometer. The standard list of proteins was obtained UNIPROT, through the use of the MASCOT application. The result obtained by MASCOT was validated by the SCAFFOLD application, with a minimum of 90% probability. Identified proteins were functionally categorized using Mapman program. Once the differentially abundant proteins for BGH-2127 and Santa Clara genotypes were listed, the construction of a protein-protein interaction network was carried out using the STRING software. Real-time PCR assays (RT-PCR) were performed to confirm the levels of abundance of some identified proteins. Total RNA was extracted from leaf samples and the cDNA obtained was quantified by the SpectraMax M5 microplate/cuvette reader. The PCR reaction was performed using StepOneTM Real- Time PCR System. Quantification of gene expression was performed using REST software. In evaluation of the constitutive proteome, nineteen proteins were identified, which were then related to metabolism and energy, photosynthesis, transcription, stress and defenses. Approximately 90% of these proteins were more abundant in Santa Clara, a susceptible cultivar. Acidic 26 kDa endochitinase and ribonuclease T2 proteins were more abundant in BGH-2127 access. The enzymatic activity confirmed a greater abundance of chitinase in the BGH-2127 access as compared to the cultivar Santa Clara. Gene expression analyses by real time PCR demonstrated that the mRNA levels were not correlated with the respective protein levels. Abundance of the acidic 26 kDa endochitinase and ribonuclease T2 proteins in the constitutive proteomes of BGH-2127 may be associated with the answer to the resistance of this access. In evaluating the response to the pathogen, fifty-six differentially abundant proteins were identified, with thirty-nine referring to the resistant genotype and seventeen to the susceptible genotype. These proteins were categorized into functional groups of energy and metabolism, photosynthesis, stress and defense, transcription, other proteins and not characterized. For access BGH-2127, oxidative stress proteins (2-cis peroxiedoxin BAS1 and 2-cis peroxiredoxin) and thaumatin-like protein had levels of relative abundance increased at times 0 and 48 hours after respectively, and were considered important for the defense mechanism of this genotype. The expression standards evaluated by RT-PCR differed from the results of the proteomic analysis. Protein-protein interaction networks provided important information on cellular activities involved in the resistance of BGH-2127 late blight. Abundance of the acidic 26 kDa endochitinase and ribonuclease T2 proteins in the constitutive proteomes of BGH-2127 may be associated with the answer to the resistance of this access. Proteins related to oxidative stress (PR-9) and thaumatin-like family (PR-5) play an important role in the BGH-2127 access defense mechanism resistant to tomato late blight.

The work is aimed to study of morphological variability of Phytophthora alni complex in the area of the Czech Republic with use of numerical phenetics. The morphological analysis of 29 Phytophthora alni strains acquired from the area of the pathogen in the Czech Republic was carried out. In total there were studied 50 cultural and morphological characteristics: 14 cultural characteristics, 16 characteristics describing asexual and 20 characteristics describing sexual structures. The all morphological measurements were repeated twenty times at magnification 1600× with use of Olympus BH-2 microscope, Olympus E-510 camera and Quick Photocamera 2.3 measuring software. The data were processed in Statistica 8.0 in modules of non-parametric statistics, descriptive statistics, cluster analysis, analysis of principal components and discriminant analysis. In the area there was confirmed the presence of the two taxa belonging to the P. alni complex: Phytophthora alni subsp. alni (Paa) a Phytophthora alni subsp. uniformis (Pau). The third taxon (P. alni subsp. multiformis) was not found. The nominate subspecies Paa prevailed - more than 4/5 of studied isolates belonged to this taxon. The classification of isolates was in full agreement with molecular study of identical set of isolates which was parallely performed (Štěpánková et al. 2013). The morphological analysis showed, that majority of Czech isolates of P. alni complex can be successfully determined on the basis of standard morphological characters -- oogonial wall ornamentation, antheridial length, rate of aborted oogonia etc. Ca 10 % of isolates were found to be intermediate. All studied isolates were divided with series of cluster and PCA analysis in two relevant clusters and a discriminant function dividing the isolates in the two taxa on basis of morphological characters was generated and validated. The rate of standard oogonia, high of oogonial ornamentation, rate of two-celled antheridia with central septum and antheridial length were used as discriminators. The two different Paa morphotypes were found in the area of the Czech Republic. The discriminant function dividing the Paa isolates in these two morphotypes was also constructed and tested. The discriminators were oogonia diameter, high of oogonial ornamentation and width of antheridium. The most reliable character was the antheridial width: the north-western morphotype has antheridia wider by 3 micrometres than the south-eastern one. The Paa taxon was continuously distributed in the western part of the area, its frequency diminshes eastward. The distribution of the second taxon - Pau - was scattered and insular, but it was found out in the whole area of the Czech Republic. It could be supposed, that the parental taxon Pau had spread before Paa invasion in the area. Later the new and more combative Paa replaced the older weakly pathogenic Pau. The recent area of Pau is apparently insular and probably relict. The two Paa morphotypes importantly differ in their distribution - the first morphotype is more frequent in north-western part of the area (and predominates in western, central and northern Bohemia) while the second one is frequent in the south-eastern part (southern Bohemia and Moravia). Likely, these two subpopulations can represent the remains of colonisation waves of two allopatric Paa lineages. The lineages can originated by repeated independent hybridisation between parental Pau and Pam taxa somewhere in western or central Europe.

Made available in DSpace on 2014-06-11T19:26:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-12Bitstream added on 2014-06-13T20:15:30Z : No. of bitstreams: 1 santos_hs_me_botfca.pdf: 1056814 bytes, checksum: 16624762488626f91755fcda1e8e3cc2 (MD5) / Com o objetivo de avaliar a viabilidade de utilização da enxertia em plantas de pimentão (Capsicum annuum, L.), visando ao controle da murcha de fitóftora, causada por Phytophthora capsici Leonian, instalou-se um experimento na Fazenda de Ensino Pesquisa e Produção de São Manuel da Faculdade de Ciências Agronômicas / UNESP – Campus de Botucatu. As plantas foram conduzidas em ambiente protegido, num módulo de estrutura simples, tipo arco, com 7,0 m de largura, 40,0 m de comprimento e 3,0 m de pé direito, coberto por filme de polietileno de baixa densidade de 100 micras , totalizando uma área de 280 m2. O período de condução foi de setembro de 2000 a julho de 2001. Na Fase 1 do estudo, os tratamentos se constituíram da combinação de dois híbridos, AF-2638 e AF-2640, resistentes a P, capsici utilizados como porta-enxertos, enxertados por garfagem fenda simples em três híbridos comerciais suscetíveis, ‘Magali-R’, ‘Elisa’ e ‘Margarita’ utilizados como enxertos. Estes três híbridos suscetíveis também foram utilizados como pés francos. Esta Fase foi da semeadura até a morte dos pés francos suscetíveis após a infestação do solo com o fungo, 14 dias após o transplante. A Fase 2 constou da condução das plantas enxertadas, que permaneceram vivas devido à resistência dos porta-enxertos, até a obtenção dos frutos provenientes de 9 colheitas. O delineamento experimental foi de blocos casualizados, com 4 repetições e 5 plantas por parcela. Na Fase 1 as características avaliadas foram a compatibilidade inicial de enxertia, expressa pela porcentagem de pegamento; resistência das plantas após a inoculação dos propágulos infectivos do fungo; evolução dos sintomas da doença nos pés francos; tempo gasto em dias da semeadura até a antese da primeira flor... . / With the purpose of verifying the viability of sweet pepper (C. annuum, L.) grafting to control Phytophthora blight, caused by Phytophthora capsici a experiment was carried out at F.C.A/UNESP, São Manuel Experimental Farm, São Paulo, Brazil, under a simple frame arctype vinil house, 7,0m wide, 40,0m long and 3,0m high, covered with a 100mm plastic film. The experimental design was a randomized block with four replication and five plants per plot and the evaluation period was from September 2000 to July 2001. In the first experimental phase three susceptible sweet pepper commercial hybrids (‘Magali-R’, ‘Elisa’ and ‘Margarita’) were cleft grafted on two resistant rootstocks (‘AF-2638’ and ‘AF-2640’) and plants were grown on soil infected with P.capsici, 14 days after transplanting. Ungrafted susceptible hybrids were utilized as a control and grafting compatibility, plant resistance, disease symptom evolution and number of days for flowering were recorded. In the second phase plant height, number weight, length and wall thickness of fruits as well as total and commercial fruit yield of the surviving plants were recorded for nine harvesting dates. Good compatibility between stock and rootstock was observed (93%) and grafted plant did not shower any symptoms of the disease during the evaluation period. The hybrid ‘Elisa’ was the most susceptible one when grown as ungrafted plants, with the faster disease evolution after soil infectation. Ungrafted plants flowered earlier than grafted ones and rootstocks interfered on plant height depending on the studied combinations. The hybrid ‘Magali’grafted on ‘AF-2639’produced the highest number of fruits. Among hybrids ‘Margarita’was intermediate as far as number and fruit weight is concerned. Grafted plants, besides... (Complete abstract, click electronic address below).

Made available in DSpace on 2014-06-11T19:35:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-07Bitstream added on 2014-06-13T19:24:12Z : No. of bitstreams: 1 siviero_a_dr_botfca.pdf: 1011233 bytes, checksum: b962f917617fbd995aa744e10e7a84f4 (MD5) / O presente estudo teve como objetivos selecionar isolados de Phytophthora parasitica com alta agressividade em citros, avaliar métodos de inoculação em genótipos quanto à resistência a gomose de Phytophthora e detectar marcadores moleculares ligados a locos controladores de características quantitativas (QTLs) de resistência a gomose. Foram testados 15 isolados de P. parasitica procedentes do Estado de São Paulo. As plantas foram inoculadas por meio de contato, método do disco, inserção sob casca, agulha e palitode- dente infestado com o patógeno. Para o trabalho de detecção de marcadores e QTLs foram inoculados 98 indivíduos de uma progênie F1, obtida do cruzamento entre Citrus sunki, parental suscetível, e Poncirus trifoliata ‘Rubidoux’, parental altamente resistente ao patógeno. As avaliações fenotípicas da resistência a gomose da progênie foram incorporadas aos mapas de ligação de P. trifoliata ‘Rubidoux’ e C. sunki, estabelecidos através de 170 marcadores moleculares do tipo RAPD, usando a estratégia de ‘pseudo testcross’. Os isolados apresentaram variação na agressividade quando inoculados em C. limon Burmann. e C. limonia Osbeck. com destaque para o isolado, LRS23/97. A avaliação de resistência de genótipos de citros a gomose pode ser realizada em plântulas e ‘in vitro’, através de inserção de agulha infestada com o patógeno e através do método do disco e da inserção sob casca em plantas com diâmetro acima de 4,0 mm. Os indivíduos da população F1, inoculados artificialmente através do método do disco, apresentaram lesões intermediárias em relação aos parentais. A herdabilidade do caráter foi de 18,7%. Foram detectados 36 marcadores moleculares associados à resistência a gomose, dos quais, 19 mapeados em P. trifoliata ‘Rubidoux’ e 10 em C. sunki... . / The objectives of the study were to select Phytophthora parasitica isolates with high agressivity on citrus, to evaluate inoculation methods and to detect molecular markers linked to resistance QTLs to Phytophthora gummosis. Fifth teen isolates of P. parasitica from the State of São Paulo were tested. Young plants were inoculated and by contact, through the insertion of a disc and tricking infested, needle and toothpick infested with pathogen. For the markers and QTLs detection, 98 individuals of the F1 progeny obtained from Citrus sunki, (susceptible parent) and Poncirus trifoliata ‘Rubidoux’, (resistant) cross were inoculated. The phenotypic evaluations for Phytophthora gummosis resistance were incorporated on genetic linkage maps built with 170 RAPD markers using the pseudotestcross strategy. The isolates showed variation in agressivity when inoculated on Citrus limon Burmann. and Citrus limonia Osbeck. The LRS23/97 isolate showed more agressivity. The citrus genotypes evaluation to resistance to Phytophphtora gummosis were made in seedlings and ‘in vitro’ by needle insertion with pathogen, disc insertion method under bark and disc method in plants with diameter larger than 4,0 mm. The F1 hybrids, which were artificially inoculated by disc method, showed intermediates symptoms compared to the parents. The heretability of Phytophthora gummosis resistance was 18,7%. 36 molecular markers were associated to Phytophthora gummosis resistance and 19 were associated with P. trifoliata ‘Rubidoux’ map and 10 with C. sunki map. It was also detected 3 QTLs linked to Phytophthora gummosis resistance on I, II and V linkage groups of P. trifoliata ‘Rubidoux’ map and 1 QTL on II linkage group of C. sunki map. The phenotypic variation ratio explained by association markers-QTLs, was in a range of 14 to 60% for P. trifoliata ‘Rubidoux’ and... (Complete abstract, click electronic address below).

Orientador: Rumy Goto / Resumo: Com o objetivo de avaliar a viabilidade de utilização da enxertia em plantas de pimentão (Capsicum annuum, L.), visando ao controle da murcha de fitóftora, causada por Phytophthora capsici Leonian, instalou-se um experimento na Fazenda de Ensino Pesquisa e Produção de São Manuel da Faculdade de Ciências Agronômicas / UNESP - Campus de Botucatu. As plantas foram conduzidas em ambiente protegido, num módulo de estrutura simples, tipo arco, com 7,0 m de largura, 40,0 m de comprimento e 3,0 m de pé direito, coberto por filme de polietileno de baixa densidade de 100 micras , totalizando uma área de 280 m2. O período de condução foi de setembro de 2000 a julho de 2001. Na Fase 1 do estudo, os tratamentos se constituíram da combinação de dois híbridos, AF-2638 e AF-2640, resistentes a P, capsici utilizados como porta-enxertos, enxertados por garfagem fenda simples em três híbridos comerciais suscetíveis, 'Magali-R', 'Elisa' e 'Margarita' utilizados como enxertos. Estes três híbridos suscetíveis também foram utilizados como pés francos. Esta Fase foi da semeadura até a morte dos pés francos suscetíveis após a infestação do solo com o fungo, 14 dias após o transplante. A Fase 2 constou da condução das plantas enxertadas, que permaneceram vivas devido à resistência dos porta-enxertos, até a obtenção dos frutos provenientes de 9 colheitas. O delineamento experimental foi de blocos casualizados, com 4 repetições e 5 plantas por parcela. Na Fase 1 as características avaliadas foram a compatibilidade inicial de enxertia, expressa pela porcentagem de pegamento; resistência das plantas após a inoculação dos propágulos infectivos do fungo; evolução dos sintomas da doença nos pés francos; tempo gasto em dias da semeadura até a antese da primeira flor... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: With the purpose of verifying the viability of sweet pepper (C. annuum, L.) grafting to control Phytophthora blight, caused by Phytophthora capsici a experiment was carried out at F.C.A/UNESP, São Manuel Experimental Farm, São Paulo, Brazil, under a simple frame arctype vinil house, 7,0m wide, 40,0m long and 3,0m high, covered with a 100mm plastic film. The experimental design was a randomized block with four replication and five plants per plot and the evaluation period was from September 2000 to July 2001. In the first experimental phase three susceptible sweet pepper commercial hybrids ('Magali-R', 'Elisa' and 'Margarita') were cleft grafted on two resistant rootstocks ('AF-2638' and 'AF-2640') and plants were grown on soil infected with P.capsici, 14 days after transplanting. Ungrafted susceptible hybrids were utilized as a control and grafting compatibility, plant resistance, disease symptom evolution and number of days for flowering were recorded. In the second phase plant height, number weight, length and wall thickness of fruits as well as total and commercial fruit yield of the surviving plants were recorded for nine harvesting dates. Good compatibility between stock and rootstock was observed (93%) and grafted plant did not shower any symptoms of the disease during the evaluation period. The hybrid 'Elisa' was the most susceptible one when grown as ungrafted plants, with the faster disease evolution after soil infectation. Ungrafted plants flowered earlier than grafted ones and rootstocks interfered on plant height depending on the studied combinations. The hybrid 'Magali'grafted on 'AF-2639'produced the highest number of fruits. Among hybrids 'Margarita'was intermediate as far as number and fruit weight is concerned. Grafted plants, besides... (Complete abstract, click electronic address below). / Mestre

Orientador: Edson Luiz Furtado / Resumo: O presente estudo teve como objetivos selecionar isolados de Phytophthora parasitica com alta agressividade em citros, avaliar métodos de inoculação em genótipos quanto à resistência a gomose de Phytophthora e detectar marcadores moleculares ligados a locos controladores de características quantitativas (QTLs) de resistência a gomose. Foram testados 15 isolados de P. parasitica procedentes do Estado de São Paulo. As plantas foram inoculadas por meio de contato, método do disco, inserção sob casca, agulha e palitode- dente infestado com o patógeno. Para o trabalho de detecção de marcadores e QTLs foram inoculados 98 indivíduos de uma progênie F1, obtida do cruzamento entre Citrus sunki, parental suscetível, e Poncirus trifoliata 'Rubidoux', parental altamente resistente ao patógeno. As avaliações fenotípicas da resistência a gomose da progênie foram incorporadas aos mapas de ligação de P. trifoliata 'Rubidoux' e C. sunki, estabelecidos através de 170 marcadores moleculares do tipo RAPD, usando a estratégia de 'pseudo testcross'. Os isolados apresentaram variação na agressividade quando inoculados em C. limon Burmann. e C. limonia Osbeck. com destaque para o isolado, LRS23/97. A avaliação de resistência de genótipos de citros a gomose pode ser realizada em plântulas e 'in vitro', através de inserção de agulha infestada com o patógeno e através do método do disco e da inserção sob casca em plantas com diâmetro acima de 4,0 mm. Os indivíduos da população F1, inoculados artificialmente através do método do disco, apresentaram lesões intermediárias em relação aos parentais. A herdabilidade do caráter foi de 18,7%. Foram detectados 36 marcadores moleculares associados à resistência a gomose, dos quais, 19 mapeados em P. trifoliata 'Rubidoux' e 10 em C. sunki... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The objectives of the study were to select Phytophthora parasitica isolates with high agressivity on citrus, to evaluate inoculation methods and to detect molecular markers linked to resistance QTLs to Phytophthora gummosis. Fifth teen isolates of P. parasitica from the State of São Paulo were tested. Young plants were inoculated and by contact, through the insertion of a disc and tricking infested, needle and toothpick infested with pathogen. For the markers and QTLs detection, 98 individuals of the F1 progeny obtained from Citrus sunki, (susceptible parent) and Poncirus trifoliata 'Rubidoux', (resistant) cross were inoculated. The phenotypic evaluations for Phytophthora gummosis resistance were incorporated on genetic linkage maps built with 170 RAPD markers using the pseudotestcross strategy. The isolates showed variation in agressivity when inoculated on Citrus limon Burmann. and Citrus limonia Osbeck. The LRS23/97 isolate showed more agressivity. The citrus genotypes evaluation to resistance to Phytophphtora gummosis were made in seedlings and 'in vitro' by needle insertion with pathogen, disc insertion method under bark and disc method in plants with diameter larger than 4,0 mm. The F1 hybrids, which were artificially inoculated by disc method, showed intermediates symptoms compared to the parents. The heretability of Phytophthora gummosis resistance was 18,7%. 36 molecular markers were associated to Phytophthora gummosis resistance and 19 were associated with P. trifoliata 'Rubidoux' map and 10 with C. sunki map. It was also detected 3 QTLs linked to Phytophthora gummosis resistance on I, II and V linkage groups of P. trifoliata 'Rubidoux' map and 1 QTL on II linkage group of C. sunki map. The phenotypic variation ratio explained by association markers-QTLs, was in a range of 14 to 60% for P. trifoliata 'Rubidoux' and... (Complete abstract, click electronic address below). / Doutor

Orientador: Herculano Penna Medina Filho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-27T12:36:02Z (GMT). No. of bitstreams: 1 Carvalho_MarliRezendeTessarinide_D.pdf: 5553083 bytes, checksum: ff21d935db0e813566223a662e7f232d (MD5) Previous issue date: 2000 / Doutorado

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