Os recursos genéticos vegetais apresentam um valor real e potencial para a agricultura em razão da sua importância em programas de melhoramento e conservação. Este estudo teve como objetivo principal caracterizar a diversidade genética e química do germoplasma de gengibre do Departamento de Genética da ESALQ/USP, por meio de 18 descritores fenotípicos, 13 combinações de marcadores AFLP e análise da composição química do óleo essencial. O germoplasma foi formado por acessos procedentes de distintos estados brasileiros, além de algúns acessos introduzidos da Colômbia. Durante as coletas, foram entrevistados 34 agricultores de três estados: São Paulo (SP), Espírito Santo (ES) e Paraná (PR), constatando-se que esta espécie é cultivada principalmente por agricultores familiares cuja fonte principal de renda é a agricultura. Na análise da composição química, um total de 61 compostos foram identificados, sendo que os acessos apresentaram variabilidade química segundo a análise de variância. O óleo essencial foi rico em monoterpenos (82,35%), destacando-se geranial (20,41%) e neral (13,36%) como os compostos mais abundantes. Os compostos α-zingibereno, 1,8-cineol, linalol e β-felandreno, foram importantes na análise da diversidade química e, portanto, determinantes no agrupamento baseado no método de ligação completa (LC-VD) que classificou o germoplasma em dois grupos de acessos: cultivares e cultivares locais. Na caracterização agromorfológica, pouca variação foi observada para variáveis qualitativas, enquanto que para variáveis quantitativas houve moderada a baixa variabilidade, embora alguns acessos divergentes foram identificados. A análise de componentes principais explicou 82% da variação total nos primeiros três componentes, sendo que a distribuição dos acessos no gráfico de dispersão foi congruente com os agrupamentos formados pelo método de otimização de Tocher, destacando-se os acessos Gen-18, Gen-24, Gen-65 e Gen-42 como os mais divergentes do germoplasma fenotípicamente. Na caracterização molecular, 13 combinações de primers AFLP geraram, em média, 113,5 locos polimórficos, com uma proporção de 96,85% de polimorfísmo na coleção global. As estimativas de diversidade genética de Nei (Hj), índice de Shannon (I) e número efetivo de alelos (ne), foram superiores nos acessos colombianos (0,501; 0,396 e 1,508, respectivamente), em relação aos acessos brasileiros. A AMOVA mostrou que a maior parte da variação (63%) ocorreu entre os dois países e o índice FST=0,153 corroborou este resultado, indicando alta diferenciação genética entre eles. Os agrupamentos fornecidos pelo Structure e o dendrograma baseado no complemento do coeficiente de Jaccard, foram consistentes entre si e demonstraram que a maioria dos acessos brasileiros são altamente similares, sendo que não há influência da procedência geográfica no padrão dos agrupamentos químicos, fenotípicos e moleculares. A introdução de novos materiais genéticos no Brasil, certamente contribuirá para uma base genética mais ampla deste cultivo. / Plant genetic resources exhibit a true and potential value for agriculture due to their importance in breeding and conservation programs. This study aimed to characterize the genetic and chemistry diversity of ginger germplasm of Genetics Department of the ESALQ/USP, through 18 phenotypic descriptors, 13 AFLP markers combinations and chemical composition analysis of essential oil. The germplasm was combined by accessions coming from diferent Brazilian states, along with some accessions introduced from Colombia. During the collection, 34 farmers were interviewed in three states: São Paulo (SP), Espírito Santo (ES) and Paraná (PR). Ginger is mainly cultivated by small farmers whose main income source is agriculture. In the chemical composition analysis, a total of 61 compounds were identified. The accessions presented chemical variability according to the analysis of variance. The essential oil was rich in monoterpenes (82.35%), being the geranial (20.41%) and the neral (13.36%), both referred to as citral, the most abundant compounds. The α-zingiberene, 1,8-cineole, linalool and β-phellandrene compounds were relevant in the chemical diversity analysis of the accessions, while the dendrogram based on the complete linkage method (LC-VD) classified the germplasm into two groups: landraces and cultivars accessions. In the agro-morphologic characterization, qualitative traits showed little variation, while moderate to low variability was observed for quantitative traits, although some divergent accessions were identified. The principal component analysis explained 82% of the total variation in the first three components, wherein the accessions distribution on the scatter plot was consistent with the groups formed by the Tocher method, with the Gen-18, Gen -24, Gen-65 and Gen-42 accessions as the most divergent ones from the phenotypically germplasm. In the molecular characterization, 13 AFLP markers combinations generated an average of 113.5 polymorphic loci, with a ratio of 96.85% of polymorphism in the overall collection. Estimates of Nei genetic diversity (Hj), Shannon index (I) and alleles effective number (ne) were higher in Colombian accessions (0.501; 0.396 and 1.508, respectively). The AMOVA showed that most of the variation (63%) occurs between the two countries and the FST=0.153 index suportted this result, indicating high genetic differentiation between Brazilian and Colombian accessions. The groupings provided by Structure and the dendrogram based on Jaccard coefficient complement were consistent with each other and showed that Brazilian accessions are genetically similar. In general, there is no influence of the accesses geographic origin in the chemical, phenotypic and molecular grouping pattern. The introduction of new genetic materials in Brazil, will certainly contribute to a broader genetic basis of this species.

Resumo: O presente trabalho foi desenvolvido com a finalidade de avaliar a variabilidade morfoagronômica de Passiflora cincinnata Mast., distribuída em diferentes regiões agroecológicas do Nordeste brasileiro. Foram utilizadas 32 características obtidas em experimento conduzido na Embrapa Semi-Árido, em Petrolina-PE, em delineamento de blocos ao acaso com quatro repetições. O desempenho dos acessos foi avaliado pela análise univariada e os estudos relativos à divergência genética foram realizados com base nos procedimentos multivariados, utilizando-se a distância generalizada de Mahalanobis (D2) e a técnica de agrupamento por variáveis canônicas. A dispersão gráfica dos acessos teve como eixos as primeiras variáveis canônicas. A estratégia de coleta de acessos de P. cincinnata mostrou-se efetiva porque os acessos coletados apresentaram variabilidade genética para todos os descritores utilizados na avaliação. Os caracteres mais importantes para discriminação entre acessos foram: diâmetro das hastes (DH), número de glândulas foliares (NGF), número de glândulas por bráctea (NGB), viabilidade de pólen (VP), massa do fruto (PF), massa da semente (MS) e massa total de frutos (MTF). Contudo, por serem caracteres influenciados pelo ambiente, os acessos devem ser avaliados em mais de um ambiente. O agrupamento dos acessos com base em suas variabilidades genéticas não foi correlacionado com sua origem geográfica. Foram obtidos acessos que, pela alta produtividade de frutos, podem ser recomendados para cultivos experimentais em áreas de produtores. / Abstract: The present work was developed aiming at evaluating the morphoagronomic variability of Passiflora cincinnata Mast., which is distributed in different agroecological regions in Northeast Brazil. Data from 32 characters were used in experiments, carried out at Embrapa Tropical Semi-Arid, Petrolina-PE, Brazil, in a randomized complete block design with four replications. The behaviour of accesses was evaluated by univariate analysis and the studies related to the genetic diversity were done based on the multivariate procedures, using the general distance of Mahalanobis (Dø) and the grouping technique by canonic variables. The graphic dispersion of the accesses used the first canonic variables as axis. The strategies for collecting the accesses of P. cincinnata proved to be effective because the collected accesses showed genetic variability for all the descriptors used in the evaluation. The most important characters for the discrimination among accesses were: stem diameter (SD), number of leaf glands (NLG), number of glands per bract (NGB), pollen viability (PV), fruit mass (FM), seed mass (SM) and total fruit mass (TFM). However, as the environment influences the characters, the accesses must be evaluated in more than one environment. Grouping of accesses based on their genetic variability was not correlated with their geographic origin. Since some accesses showed high fruit productivity, they can be recommended to farmers for experimental growing. / Orientador: Norberto da Silva / Coorientador: Manoel Abilio de Queiróz / Banca: Rumy Goto / Banca: João Domingos Rodrigues / Banca: Grécia Cavalcanti da Silva / Banca: Natoniel Franklin de Melo / Doutor

Maize is susceptible to biotic and abiotic stresses. The most important abiotic stresses in Africa are drought and low soil fertility. Aflatoxin contamination is a potential problem in areas facing drought and low soil fertility. Three studies were conducted to evaluate maize germplasm for tolerance to stress. In the first study, fifteen maize inbred lines crossed in a diallel were evaluated under drought, low N stress, and well-watered conditions at six locations in three countries to estimate general (GCA) and specific combining ability (SCA), investigate genotype x environment interaction, and estimate genetic diversity and its relationship with grain yield and heterosis. GCA effects were not significant for grain yield across environments. Lines with good GCA effect for grain yield were P501 and CML258 across stresses. Lines CML339, CML341, and SPLC7-F had good GCA effects for anthesis silking interval across stresses. Additive genetic effects were more important for grain yield under drought and well-watered conditions. Heterosis estimates were highest in stress environments. Clustering based on genetic distance calculated using marker data from AFLP, RFLP, and SSRs grouped lines according to origin. Genetic distance was positively correlated with grain yield and specific combining ability. In the second study, synthetic hybrids were evaluated at seven locations in three countries to estimate GCA and SCA effects under low N stress and optimal conditions and investigate genotype x environment interaction. GCA effects were significant for all traits across low N stress and optimal conditions. The highest yielding synthetic hybrids involved synthetics developed from stress tolerant lines. Synthetics 99SADVIA-# and SYNA00F2 had good GCA for grain yield across low N stress conditions. Heterosis was highly correlated with grain yield. Optimal environments explained more variation than stress environments. The third study evaluated the agronomic performance and aflatoxin accumulation of single and three-way cross white maize hybrids at five locations in Texas. Inbreds CML343, Tx601W, and Tx110 showed positive GCA effects for grain yield. Significant GCA effects for reduced aflatoxin concentration were observed in lines CML269, CML270, and CML78 across locations. Differences in performance between single and three-way crosses hybrids were dependent mostly on the inbred lines.

Maize is susceptible to biotic and abiotic stresses. The most important abiotic stresses in Africa are drought and low soil fertility. Aflatoxin contamination is a potential problem in areas facing drought and low soil fertility. Three studies were conducted to evaluate maize germplasm for tolerance to stress. In the first study, fifteen maize inbred lines crossed in a diallel were evaluated under drought, low N stress, and well-watered conditions at six locations in three countries to estimate general (GCA) and specific combining ability (SCA), investigate genotype x environment interaction, and estimate genetic diversity and its relationship with grain yield and heterosis. GCA effects were not significant for grain yield across environments. Lines with good GCA effect for grain yield were P501 and CML258 across stresses. Lines CML339, CML341, and SPLC7-F had good GCA effects for anthesis silking interval across stresses. Additive genetic effects were more important for grain yield under drought and well-watered conditions. Heterosis estimates were highest in stress environments. Clustering based on genetic distance calculated using marker data from AFLP, RFLP, and SSRs grouped lines according to origin. Genetic distance was positively correlated with grain yield and specific combining ability. In the second study, synthetic hybrids were evaluated at seven locations in three countries to estimate GCA and SCA effects under low N stress and optimal conditions and investigate genotype x environment interaction. GCA effects were significant for all traits across low N stress and optimal conditions. The highest yielding synthetic hybrids involved synthetics developed from stress tolerant lines. Synthetics 99SADVIA-# and SYNA00F2 had good GCA for grain yield across low N stress conditions. Heterosis was highly correlated with grain yield. Optimal environments explained more variation than stress environments. The third study evaluated the agronomic performance and aflatoxin accumulation of single and three-way cross white maize hybrids at five locations in Texas. Inbreds CML343, Tx601W, and Tx110 showed positive GCA effects for grain yield. Significant GCA effects for reduced aflatoxin concentration were observed in lines CML269, CML270, and CML78 across locations. Differences in performance between single and three-way crosses hybrids were dependent mostly on the inbred lines.

Maize is the principal crop for food security and livestock feed in South Africa. It is also an industrial crop and the produce is exported to many countries in the world. Therefore there is high seed demand which prompts competition for breeding productive hybrids. However direct introduction of tropical hybrids into the warm temperate South African environments has not been successful. Competitive advantages can be obtained by implementing a “shuttle breeding” programme whereby part of the breeding is done in Zimbabwe and South Africa to minimise research and production costs. Introgression of temperate germplasm in tropical elite inbred lines can also be pursued to obtain adapted hybrids. The aim of this study was therefore to assess the effectiveness of introgression of temperate germplasm into tropical elite maize inbred lines as a strategy to enhance adaptability of new hybrids to South Africa, and also to determine both breeding and economic value of a “shuttle breeding” programme. To this end, the introgressed inbred lines and their hybrid progenies were evaluated in South Africa to determine the effect of the selection environment on their performance and genetic variation. Both genetic and economic gains were evaluated with a view to make recommendations to the small and medium scale enterprises with interests in the market. Introgression of temperate germplasm into tropical germplasm elite lines did not disrupt the heterotic groupings because most of the introgressed lines (86%) fitted into known existing heterotic groups. Only 14% of the introgressed lines did not show any inclination to towards the known heterotic clusters of their founder tropical parents. These lines were considered to be new recombinant inbred lines that showed little resemblance with their founder parents. Selection environment did not influence heterotic clustering of the introgressed lines, and genetic diversity was identified among introgressed lines developed in the same environment. Genetic variation was observed for the major economic traits and heritability of 21% to 91%. The introgression was effective for improving grain yield potential and ear prolificacy. Spearman’s rank correlation analysis on grain yield and ear prolificacy data showed significant positive correlation between selection environments such as Ukulinga in South Africa and Kadoma Research Centre in Zimbabwe. Therefore Kadoma Research Centre will be recommended for use in breeding new maize germplasm lines for South Africa. Correlation among traits showed that ear prolificacy and plant height had significant (P<0.05) direct effects on grain yield thus direct selection of these traits will be emphasised in breeding new hybrids. Introgression of temperate germplasm into tropical elite maize inbred lines was effective for improving their adaptation to warm temperate environments. Positive genetic gains of 5-58% were realised for grain yield potential and 26-46% for ear prolificacy. Whereas 1% to 37% gains were realised for secondary traits such as plant and ear height, anthesis and silking days there was barely any improvement for root and stalk lodging, and grain moisture content at harvest. However, introgressed lines displayed impressive performance per se and inter se indicating potential for commercial production. The new inbred line 71-DMLF7_88 combined early physiological maturity, high ear prolificacy and grain yield potential qualifying it as a perfect parent for the warm temperate environments. At least six hybrids were stable and adaptable while four were considered to be ideal genotypes relative to standard commercial hybrids such as PAN6Q445B which is a market leader. The exceptional hybrids, 12C20264, 12C22766, 13XH349 and 11C11774 will be advanced in South Africa. The study also indicated significant economic gains when a shuttle programme is implemented to breed new hybrids following the introgression strategy. The “Shuttle breeding” programme attained a positive net present value (NPV) of $1, 834, 166. 00. This indicated an increase in shareholder value through an opportunity cost of 17% and 3% relative to conventional breeding programmes which are based in South Africa and Zimbabwe, respectively. Positive NPV and genetic gain achieved using the “shuttle breeding” programme makes it a viable option for small and medium scale seed companies with intention to breed and commercialise competitive products in South African. In general, the study revealed that introgression of temperate germplasm into tropical elite inbred lines using a “shuttle breeding” programme was effective for enhancing adaptability of tropical germplasm to the South African warm temperate environments. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Includes bibliographical references (leaves 232-257). / xv, 257 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Aims to determine if the compatible solutes (proline, glycine betaine, and trehalose), the epididymal compounds (taurine, hypotaurine and inositol) or the antioxidants (carnosine and ascorbic acid) in tris-citrate based diluents could improve the post-thaw survival and/or fertility of ram spermatazoa. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 1996?

Made available in DSpace on 2016-08-12T19:15:42Z (GMT). No. of bitstreams: 1 AnaCAD_DISSERT.pdf: 992908 bytes, checksum: 8c8ed25d36c890fc913b87012539bb33 (MD5) Previous issue date: 2011-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The melon plant is distributed worldwide and is the kind that has the highest phenotypic variability of the genus, especially observed in its fruit. There is great variability which consists an important source of germplasm for genetic improvement programs. Therefore, the knowledge of the genetic variability of vegetable species and how it distributes itself, provides the rational and sustainable use of genetic resources. The objective of the present study was to do a morphological and molecular characterization of accessions of melon plant collected in brazilian northeastern. Were evaluated 40 accesses and three commercial cultivars in a trial conducted in randomized complete block with two repetitions in Mossoró-RN. The morphological characterization was performed through 17 descriptors, one of the seed, fourteen of fruit and two of the inflorescence. The molecular characterization was performed by RAPD markers using 18 primers and by microsatellite (SSR) with 15 primers synthesized for Cucumis melo. It was verified that the morphological markers, RAPD and SSR were satisfactory to allow the detection of polymorphism among the genotypes evaluated. The grouping methods of Tocher and the hierarchical partially agreed on morphological and molecular characterizations. The RAPD marker was more discriminating in relation to microsatellite by the fact of cluster the accesses in most groups. The germplasm bank of UFERSA has high genetic variability among the accessions. / O meloeiro está distribuído em todo o mundo, e é a espécie que possui a maior variabilidade fenotípica do gênero, observada principalmente nos seus frutos. Existe grande variabilidade que consiste em importante fonte de germoplasma para programas de melhoramento. Portanto, o conhecimento da variabilidade genética de espécies vegetais e como ela se distribui, proporciona o uso racional e sustentável dos recursos genéticos. O objetivo do presente trabalho foi realizar a caracterização morfológica e molecular de acessos de meloeiro coletados no Nordeste brasileiro. Foram avaliados 40 acessos e três cultivares comerciais em um experimento conduzido em blocos completos casualizados com duas repetições no município de Mossoró-RN. A caracterização morfológica foi feita através de 17 descritores, sendo um da semente, quatorze de frutos e dois da inflorescência. A caracterização molecular foi realizada pelos marcadores RAPD utilizando 18 primers e por microssatélites (SSR) com 15 primers sintetizados para Cucumis melo. Verificou-se que os marcadores morfológicos, RAPD e SSR foram satisfatórios em permitir a detecção de polimorfismo entre os genótipos avaliados. Os métodos de agrupamento de Tocher e o hierárquico concordaram parcialmente nas caracterizações morfológicas e moleculares. O marcador RAPD foi mais discriminante em relação ao microssatélite pelo fato de agrupar os acessos em mais grupos. O banco de germoplasma da UFERSA possui alta variabilidade genética entre os acessos.

Made available in DSpace on 2016-08-12T19:18:57Z (GMT). No. of bitstreams: 1 AnaCAD_DISSERT.pdf: 992908 bytes, checksum: 8c8ed25d36c890fc913b87012539bb33 (MD5) Previous issue date: 2011-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The melon plant is distributed worldwide and is the kind that has the highest phenotypic variability of the genus, especially observed in its fruit. There is great variability which consists an important source of germplasm for genetic improvement programs. Therefore, the knowledge of the genetic variability of vegetable species and how it distributes itself, provides the rational and sustainable use of genetic resources. The objective of the present study was to do a morphological and molecular characterization of accessions of melon plant collected in brazilian northeastern. Were evaluated 40 accesses and three commercial cultivars in a trial conducted in randomized complete block with two repetitions in Mossoró-RN. The morphological characterization was performed through 17 descriptors, one of the seed, fourteen of fruit and two of the inflorescence. The molecular characterization was performed by RAPD markers using 18 primers and by microsatellite (SSR) with 15 primers synthesized for Cucumis melo. It was verified that the morphological markers, RAPD and SSR were satisfactory to allow the detection of polymorphism among the genotypes evaluated. The grouping methods of Tocher and the hierarchical partially agreed on morphological and molecular characterizations. The RAPD marker was more discriminating in relation to microsatellite by the fact of cluster the accesses in most groups. The germplasm bank of UFERSA has high genetic variability among the accessions. / O meloeiro está distribuído em todo o mundo, e é a espécie que possui a maior variabilidade fenotípica do gênero, observada principalmente nos seus frutos. Existe grande variabilidade que consiste em importante fonte de germoplasma para programas de melhoramento. Portanto, o conhecimento da variabilidade genética de espécies vegetais e como ela se distribui, proporciona o uso racional e sustentável dos recursos genéticos. O objetivo do presente trabalho foi realizar a caracterização morfológica e molecular de acessos de meloeiro coletados no Nordeste brasileiro. Foram avaliados 40 acessos e três cultivares comerciais em um experimento conduzido em blocos completos casualizados com duas repetições no município de Mossoró-RN. A caracterização morfológica foi feita através de 17 descritores, sendo um da semente, quatorze de frutos e dois da inflorescência. A caracterização molecular foi realizada pelos marcadores RAPD utilizando 18 primers e por microssatélites (SSR) com 15 primers sintetizados para Cucumis melo. Verificou-se que os marcadores morfológicos, RAPD e SSR foram satisfatórios em permitir a detecção de polimorfismo entre os genótipos avaliados. Os métodos de agrupamento de Tocher e o hierárquico concordaram parcialmente nas caracterizações morfológicas e moleculares. O marcador RAPD foi mais discriminante em relação ao microssatélite pelo fato de agrupar os acessos em mais grupos. O banco de germoplasma da UFERSA possui alta variabilidade genética entre os acessos.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-01-10T16:10:06Z No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-01-24T14:45:40Z (GMT) No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) / Made available in DSpace on 2017-03-21T14:50:07Z (GMT). No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The melon cultivation in semi-arid northeast in consecutive cycles has generated problems caused by fungi inhabitants of the soil, such as Fusarium solani and M. cannonballus. The use of resistant cultivars is an interesting measure for the management of the disease. For this reason, it is important identify sources of resistance and study their inheritance. The objectives of this work were: a) to evaluate the reaction of melon accessions to F. solani f. sp. Cucurbitae; b) to evaluate the reaction of accessions and study the inheritance of resistance of accession AC-33 to M. cannonballus. In the first experiment, we evaluated twenty-one accessions in a completely randomized design in greenhouse. Two isolates were inoculated fifteen days after sowing by the toothpick. The assessment was done Thirty days after inoculation with a scale scored from zero to four. The accessions AC-01, AC-09, AC-42, AC-45, AC-50 and the cultivar 'Doublon' are the most promising materials for use in breeding programs for resistance to F. solani or as rootstocks. In the second experiment, sixteen accessions and line OF-02 were evaluated in a completely randomized design. We used the isolated MC-16 to infestation of a mixture (1:1:1) with soil, peat, and sand previously sterilized with the addition of a concentration of 20 u.f.c./g soil. The evaluation was performed at 45 days using a rating scale (1-5). In the third experiment, we investigated the inheritance of resistance of accession AC-33 crossed with line OF-02 (susceptible). We observed variability in the germplasm investigated for reaction to the fungus. The AC-33 is highly resistant to access M. cannonballus and its resistance is controlled by a major gene with additive and dominant effects and polygenes with additive effects / O cultivo do meloeiro no semiárido nordestino em ciclos consecutivos tem gerado problemas causados por fungos habitantes do solo, como Fusarium solani e Monosporascus cannonballus. O uso de cultivares resistentes é uma medida interessante para o manejo da doença. Em razão disso, é importante que fontes de resistência sejam identificadas e se conheça a herança da resistência. Os objetivos do presente trabalho foram: a) avaliar a reação de acessos de meloeiro a F. solani f. sp. cucurbitae e b) avaliar a reação de acessos e estudar a herança da resistência do acesso AC-33 a M. cannonballus. No primeiro experimento, foram avaliados 21 acessos em um delineamento inteiramente casualizado em casa-de-vegetação. Foram inoculados dois isolados, com o método do palito, aos 15 dias após a semeadura. A avaliação dos acessos foi realizada 30 dias após a inoculação, com uma escala de 0 a 4. Os acessos AC-01, AC-09, AC-42, AC-45 e AC-50 e a cultivar ‘Doublon’ são os materiais mais promissores para uso em programas de melhoramento genético visando à resistência a F. solani ou como porta-enxertos. No segundo experimento, foram avaliados 16 acessos e a linhagem OF-02 em um delineamento inteiramente casualizado. Utilizou-se o isolado MC-16 para infestação de mistura em volume de 1:1:1 de terra, turfa e areia, previamente esterilizada com a adição de uma concentração 20 u.f.c./g de solo. A avaliação foi realizada aos 45 dias utilizando uma escala de notas (1 a 5). No terceiro experimento, investigou-se a herança da resistência do acesso AC-33 (resistente) cruzado com a linhagem OF-02 (suscetível). Observou-se a existência de variabilidade no germoplasma investigado para reação ao fungo. O acesso AC-33 é altamente resistente a M. cannonballus e sua resistência é controlada por um gene maior de efeito aditivo e dominante e poligenes de efeitos aditivos / 2017-01-10

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2016-11-25T14:08:49Z No. of bitstreams: 1 AnânkiaOR_DISSERT.pdf: 597580 bytes, checksum: a044a0afd2f68a5d8f127a9167ef8a63 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:38:31Z (GMT) No. of bitstreams: 1 AnânkiaOR_DISSERT.pdf: 597580 bytes, checksum: a044a0afd2f68a5d8f127a9167ef8a63 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T15:05:15Z (GMT) No. of bitstreams: 1 AnânkiaOR_DISSERT.pdf: 597580 bytes, checksum: a044a0afd2f68a5d8f127a9167ef8a63 (MD5) / Made available in DSpace on 2017-03-21T15:05:24Z (GMT). No. of bitstreams: 1 AnânkiaOR_DISSERT.pdf: 597580 bytes, checksum: a044a0afd2f68a5d8f127a9167ef8a63 (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Powdery mildew is a disease that causes substantial losses in melon production around the world. Obtaining resistant cultivars is possible through introgression of alleles in the breeding program. In this study, it was investigated the inheritance of resistance of AC-02 accession to races 1 and 5 of Podosphaera xanthii in cross with susceptible cultivar ‘Védrantais’, under greenhouses conditions. The segregations ratios for resistance/susceptibility observed in the different populations (F1, F2, RC1 and RC2) indicated a monogenic and dominant inheritance in AC-02 to races 1 and 5. The distance between the gene controlling resistance to race 1 (px1-ac02) and the gene which confers resistance race 5 (px5-ac02) is 28.5 cM. / oídio é uma doença que causa perdas significativas na produção de melão em todo o mundo. A obtenção de cultivares resistentes é feita mediante introgressão de alelos de resistência. Neste estudo, investigou-se a herança da resistência do acesso AC-02 às raças 1 e 5 de Podosphaera xanthii por meio de cruzamento com a cultivar suscetível ‘Védrantais’, sob condições de casa de vegetação. As razões de segregações de resistência/suscetibilidade observadas nas diferentes populações (F1, F2, RC1 e RC2) indicaram que a herança da resistência do AC-02 às raças 1 e 5 é controlada, cada uma por um gene composto por dois alelos, de modo que o alelo que confere resistência domina o alelo para suscetibilidade. A distância entre o gene que controla a resistência à raça 1 (px1-ac02) e o gene que confere resistência à raça 5 (px5-ac02) é 28,5 cM. / 2016-11-23