O maxixeiro (Cucumis anguria L.) é uma cultura de grande importância nas regiões Norte e Nordeste do Brasil. No entanto, a maior parte da produção brasileira desta hortaliça é obtida sem o uso de genótipos e tecnologias adequadas. Os objetivos desse trabalho foram: Fazer a caracterização fenotípica de acessos locais e comerciais de maxixe da região sul do Tocantins, avaliar sua capacidade de combinação e a ação gênica. O experimento foi conduzido em delineamento de blocos casualizados com três repetições. Os tratamentos foram nove genótipos de maxixe e suas combinações híbridas obtidas em cruzamento dialélico de acordo à metodologia proposta por Gardner e Eberhart, totalizando quarenta e cinco tratamentos. Foram coletados frutos de cultivos familiares na região sul do Tocantins e também foram adquiridos duas cultivares comerciais (Feltrin® e Topseed®), posteriormente foi multiplicado as sementes dos frutos do município de Gurupi e efetuados cruzamentos. Foram caracterizados nove genótipos com seleções de suas partes vegetativas e reprodutivas, assim como avaliarem sua ação gênica em relação às estimativas de efeitos de variedade e heterose e de seus híbridos. Avaliou-se a sua capacidade de combinação e as médias de variância dos frutos para diâmetro do fruto (mm), comprimento do fruto (mm), peso médio do fruto (g) e produtividade (tonha-1). A caracterização vegetativa dos genótipos mostrou uma leve separação entre os genótipos, principalmente nas características relacionadas ao tamanho foliar. Nas características reprodutivas, porém, não houve separação entre os genótipos e cultivares. Algumas características possuem correlação mais forte que outras, como o cultivar comercial Topseed®, que se distingue dos demais cultivares na PCA de caracteres vegetativos. No resumo de análises de variações nas características de diâmetro, comprimento, peso e firmeza do fruto foram identificados diferenças significativas, na característica de produtividade tivessem efeitos não significantes nas fontes de variações para variedade, heterose média e heterose de variedade. Na estimativa de efeito de variedade, as características diâmetro dos frutos (36,21); comprimento do fruto (45,29) e peso do fruto (32,86) o genótipo MAXGU#02 foi superior, e na característica firmeza do fruto (133,80 N) e produtividade (15,61) o genótipo MAXGU#01. Na estimativa de efeito de heterose de variedade as características de diâmetro do fruto (47,64); comprimento do fruto (80,43); peso médio dos frutos (40,18); firmeza do fruto (100,36) e produtividade (2,70) se destaca o genótipo MAXGU#03. Nas características diâmetro do fruto, comprimento do fruto e produtividade predomina os efeitos não aditivos. Nas caraterísticas peso do fruto e firmeza de polpa e casca foram efeitos aditivos, em seu desempenho “per se”. / The gherkin (Cucumis anguria L.) is a culture of great importance of in the North and Northeast of Brazil. However, most of the Brazilian production of this vegetable is obtained without the use of genotypes and appropriate technologies. The objectives of this study were phenotypic characterization local and commercial access of gherkin in the southern region of Tocantins, assess their capacity for action and the combination of genes. The experiment was conducted in a delineation of block design with three replications. The treatments were nine genotypes of gherkin and hybrids obtained in diallel crossings according to the methodology proposed by Gardner and Eberhart, totaling forty-five treatments. Fruits were collected of home gardens in the southern region of the state of Tocantins and also two commercial crops (Feltrin® e Topseed®), subsequently were multiplied the seeds of the fruits of the municipality of Gurupi and were made crosses. Were characterized nine genotypes with selections of their vegetative and reproductive parts, also its gene action was evaluated in relation to the estimates of effects of variety and heterosis and hybrids capacity combination and average variance of the fruits were evaluated for fruit diameter (mm), fruit length (mm), average fruit weight (g) and productivity (tonha-1). The vegetative characterization of the genotypes showed a slight separation between the genotypes, mainly at the characters related to the leaf size. In the reproductive traits, however, there was no separation between genotypes and cultivars. Some characters have a stronger correlation than others, such as the commercial cultivar Topseed ®, which differs from the other cultivars in PCA of vegetative characters. In the summary analysis of variation in the characteristics of fruit diameter, fruit length, fruit weight and fruit firmness were identified significant differences, whereas the characteristic productivity hadn't significant effects on the sources of variety, average heterosis and heterosis of variety. In the estimation of the effect of variety, diameter characteristics of the fruits (36.21); fruit length (45,29) and fruit weight (32,86) MAXGU#02 genotype was higher, and the feature of fruit firmness (133,80) and productivity (15,61) was the genotype MAXGU#01. The estimation of heterosis effect of variety, the characteristics fruit diameter (47,64); fruit length (80,43), average fruit weight (40.18), fruit firmness (100,36) and productivity (2,70) highlights the MAXGU#03 genotype. In the characteristics diameter, length and average weight of the fruits, additive effects predominated in their performance "per se". For firmness of pulp and peel and productivity predominate not additive effects.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-21T14:16:54Z No. of bitstreams: 1 Cintia de Sousa Bezerra.pdf: 529172 bytes, checksum: 3f8bd6778995572053eaacf5a2bbb510 (MD5) / Made available in DSpace on 2017-02-21T14:16:54Z (GMT). No. of bitstreams: 1 Cintia de Sousa Bezerra.pdf: 529172 bytes, checksum: 3f8bd6778995572053eaacf5a2bbb510 (MD5) Previous issue date: 2011-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Vine decline of melons caused by Monosporascus cannonballus is a destructive disease worldwide. To implement a meaningful management of plantation diseases, it is important to have an understanding of the population diversity of the pathogen. The aims of this study were assay de genetic structure of M. cannonballus isolates from Brazil and compare this isolates with isolates form Spain. The population genetic structure of M. cannonballus was examined by applying ISSR and mycelial compatibility tests. Based on the frequencies of MCGs, and ISSR were estimated the genotype diversity indexes, as well as its richness and evenness components. All analyses were performed by R, NTSYS and PopGen software. The isolate were from 7 plantations in Mossoró in state of Rio Grande do Norte, Quixeré and Icapuí in state of Ceará. The seven plantations showed low genetic distance between them (GST 0.004 to 0.068), when grouped into two subpopulations CE and RN genetic diversity (GST 0.105) between them was also low, reflecting a high amount of gene flow (Nm = 31), genetic diversity within subpopulations (Hs = 0.2277) was 98% of the total genetic diversity of the population (HT = 0.2314). The genotypic diversity estimated by Sttodart and Taylor was 10% of the maximum possible. Four MC groups were found amongst 58 isolates from Brazil, whereas in Spain 6 MC were found in only 11 isolates. None Brazilian isolates was compatible with Spanish isolates. Genetic variability was low and similar in the subpopulations (Icapuí, Quixeré and Mossoró) from Brazil. The genotypic diversity for Brazilian population was lower compared with the Spanish population. Based on these data, the Spanish population was more diverse than the Brazilian population. No significant difference in diversity exists between Icapui, Quixere and Mossoró subpopulations. But significant difference in diversity exists between the Brazilian and Spanish populations of M. cannonballus. / O declínio das ramas do meloeiro causado pelo fungo Monosporascus cannonballus, vem causando prejuízos nas áreas de cultivo de melão em todo o mundo. Para o desenvolvimento de estratégias de manejo é essencial conhecer a estrutura genética da população do patógeno. Os objetivos deste estudo foram descrever a estrutura genética e as forças evolutivas que atuam sobre a população de M. cannonballus, e comparar a população Brasileira a isolados coletados na Espanha. Os isolados utilizados foram coletados em sete áreas de plantio comercial nos municípios de Mossoró no Rio Grande do Norte, Quixeré e Icapuí no Ceará. Foi feita a extração do DNA genômico, seguida de uma reação ISSR para a análise genética da população. Testes de incompatibilidade micelial foram realizados em meio BDA pareando os isolados consigo e com os demais para formar grupos. Com base nas freqüências de MCGs foram calculados índices de diversidade genotípica e seus componentes de riqueza e equitabilidade. Os dados obtidos foram análisados nos programas R, NTSYS e PopGen. As sete areas coletadas apresentaram baixa distancia genética entre si (GST 0,004-0,068), quando agrupadas em duas subpopulações CE e RN a diversidade genétia (GST 0,105) entre elas ainda foi baixa refletindo num alto valor de fluxo gênico (Nm=31) e a diversidade genética dentro das sub-populações (HS = 0,2277) representou 98% da diversidade genética total da população estudada (HT = 0,2314). A diversidade genotípica estimada pelo índice G foi 10% do máximo possível. Foram formados 4 MCG entre os 58 isolados do Brasil, enquanto na Espanha 6 grupos foram formados entre apenas 11 isolados. Os isolados do Brasil não foram compatíveis com os da Espanha. Houve uma diferença significativa na diversidade entre as populações da Espanha e Brasil, enquanto que entre as subpopulações brasileiras não houve diferença.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-10T14:34:25Z No. of bitstreams: 1 Elias Inacio da Silva.pdf: 496927 bytes, checksum: d6971c4e240310675bba44bb481b6833 (MD5) / Made available in DSpace on 2017-03-10T14:34:25Z (GMT). No. of bitstreams: 1 Elias Inacio da Silva.pdf: 496927 bytes, checksum: d6971c4e240310675bba44bb481b6833 (MD5) Previous issue date: 2002-09-30 / Melon is one of the most popular cucurbits in the world. The bacterial blotch of melon, caused by Acidovorax avenae subsp. citrulli has caused 40 to 50% losses in the production and made the fruits inappropriate for commercialization in the State of Rio Grande do Norte. This study aimed to survey the bacterial blotch incidence in 18 melon planting areas of the counties Mossoró and Baraúna in Rio Grande do Norte, and to determine the ideal sample size for disease assessment. Prevalence of 100% was reported in the studied fields. The incidence of the bacterial fruit blotch ranged from 4.30 to 47.29%. Incidence levels were under 20% in 50% of the areas and higher than 40% in 17% of the areas. There was significant difference for the variables melon type (P=0.01) and years of melon culture in the area (P=0.05). The t test showed the melon Piel de sapo was more susceptible than the yellow type and the disease incidence in areas with less than 10 years of melon cropping was higher than those with more than20 years. However, there were no significant differences (P=0.05) for disease incidence averages among areas planted with corn (18%) and corn plus other grasses (20%) between melon seasons. Using the incidence data from 18 areas as pilot-samples, the sample size for disease assessment was determined according to the mean variability coefficient. The Pierson test showed no significant correlations (P=0.05) between the levels of disease incidence and sample sizes. Based on the data obtained andconsidering 10% of acceptable error, it is recommended that in future surveys of melon bacterial blotch incidence in fields in Rio Grande do Norte, a sample composed by 12 subsamples comprising 100 m2/ha and 20 fruit evaluated per subsample must be analyzed. / O meloeiro é uma das cucurbitáceas mais populares do mundo. A mancha-aquosa do melão, causada pela bactéria Acidovorax avenae subsp. citrulli, tem causado perdas de 40 a 50% na produção e depreciação no valor comercial do fruto no estado do Rio Grande do Norte. Os objetivos deste estudo foram realizar o levantamento da incidência da mancha-aquosa em 18 áreas de plantio de meloeiro dos municípios Mossoró e Baraúna, no Rio Grande do Norte e determinar o tamanho ideal das amostras para quantificação da incidência da doença no campo. Foi registrada a prevalência da doença em 100% dos campos. A incidência da mancha-aquosa variou entre 4,30% e 47,29%. Em 50% das áreas foram constatados níveis de incidência da doença inferiores a 20%, enquanto em 17% foram registrados valores superiores a 40%. Houve diferença significativa na incidência da doença em relação aos tipos de melão (P=0,01) e aos anosde plantio na mesma área (P=0,05). Pelo teste t o melão tipo Pele de sapo foi mais suscetível que o Amarelo e a incidência da doença foi maior em áreas com menos de 10 anos de plantio em relação àquelas com mais de 20 anos de plantio dessa cucurbitácea. Não foram constatadas diferenças significativas (P=0,05) pelo teste t, para médias de incidência da mancha-aquosa entre áreas com plantio de milho (18%) e milho com outras gramíneas (20%) na entressafra. Utilizando os dados de incidência da doença nas 18 áreas como amostragens-piloto, o tamanho das amostras para quantificação da doença foi determinado com base no coeficiente de variação da média. O teste de Pierson não constatou correlações significativas (P=0,05) entre os níveis de incidência da doença e o tamanho das amostras. Considerando os resultados obtidos e um erroaceitável de 10%, em futuros levantamentos da incidência da mancha-aquosa em plantios de meloeiro no Rio Grande do Norte, recomenda-se a utilização de uma amostra de 12 subparcelas com 100 m2/ha e 20 frutos avaliados por subparcela

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-13T13:36:22Z No. of bitstreams: 1 Hailson Alves Ferreira.pdf: 643394 bytes, checksum: 8f418500344c84ed57ff01ecd2383464 (MD5) / Made available in DSpace on 2017-03-13T13:36:22Z (GMT). No. of bitstreams: 1 Hailson Alves Ferreira.pdf: 643394 bytes, checksum: 8f418500344c84ed57ff01ecd2383464 (MD5) Previous issue date: 2009-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Melon bacterial blotch caused by Acidovorax avenae subsp. citrulli (Aac) is responsible for substantial yield losses in Northeastern Brazil. The research aimed at two main objectives: 1) evaluating the effects of silicon doses on the melon bacterial blotch control as a function of soil characteristics, disease epidemiological components, plant nutrition and development, and direct effect on the pathogen; and 2) evaluating the enzyme activity in melons supplied with silicon either innoculated or non-innoculated by the pathogen. Calcium silicate was added to soil at the rates 0.00; 0.25; 0.50; 1.50 e 3.00 g kg-1 SiO2. After a 20-day incubation period soil samples were taken and melon seedlings (AF 4945) were transferd to soil. The folowing characteristcs were evaluated: incubation period, disease index, area below the progress curve of the disease, and incidence at 20 days after innoculation. Analysis of plant growth and development as well as nutrients accumulation were done in 45 days-old plants. The results demonstrated that the highest Si rate promoted significant alterations in soil chemical attributes and plant nutrition and development. This rate also reduced the disease index, the area below the progress curve of the disease and the incidence, hence increasing theincubation period and controling the bacterial blotch. Silicon did not inhibit the Acidovorax avenae growth in vitro. Total proteins and superoxide dismutase isoforms were induced by Si whereas activity of peroxidade, ascorbate peroxidase, quitinase, β-1,3 glucanase, and phenylalanine ammonia-lyase were not changed by silicon. / A mancha-aquosa do meloeiro, causada pela bactéria Acidovorax avenae subsp. citrulli (Aac) ocasiona consideráveis perdas a produção. Este trabalho objetivou (1) avaliar os efeitos de diferentes doses de silício (Si) no controle da mancha-aquosa do meloeiro analisando os atributos químicos do solo, os componentes epidemiológicos da doença, a nutrição e desenvolvimento da planta e o efeito direto sobre o patógeno; (2) avaliar a atividade enzimática em meloeiros suplementados ou não com Si, inoculados e não inoculados com o patógeno O silicato de cálcio foi incorporado ao solo nas doses de 0,00; 0,25; 0,50; 1,50 e 3,00 g kg-1 SiO2. Após 20 dias de incubação, realizou-se o transplantio de mudas de meloeiro híbrido amarelo AF 4945 e análises químicas do solo. Foram avaliados período de incubação, índice de doença, área abaixo da curva de progresso da doença e incidência aos 20 dias após inoculação. Avaliações de crescimento, desenvolvimento e acúmulo de nutrientes na planta foram realizadas após 45 dias de cultivo. A maior dose de SiO2 utilizada promoveu alterações significativas nos atributos químicos do solo, na nutrição e desenvolvimento da planta, e reduziusignificativamente o índice de doença, a área abaixo da curva de progresso da doença e a incidência, aumentando o período de incubação e controlando a mancha-aquosa. O silício não inibiu o crescimento de Aac in vitro. As proteínas solúveis totais e algumas isoformas da superóxido dismutase foram induzidas pela presença do Si, enquanto as peroxidase, peroxidase do ascorbato, quitinase, β-1,3 glucanase e fenilalanina amônia liase não foram influenciadas.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-14T12:33:28Z No. of bitstreams: 1 Jeane Emili de Medeiros.pdf: 394630 bytes, checksum: 1eb59fc3e8a4ae913b395a21c71fbe51 (MD5) / Made available in DSpace on 2017-03-14T12:33:28Z (GMT). No. of bitstreams: 1 Jeane Emili de Medeiros.pdf: 394630 bytes, checksum: 1eb59fc3e8a4ae913b395a21c71fbe51 (MD5) Previous issue date: 2007-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this work was to isolate and select bacteria for the control of Meloidogyne incognita and to evaluate the isozymatic activity of melon plants parasitized. Sixty-one rhizobacterium isolates obtained from rhizosphere soil and 56 endophytic obtained from the Culture Collection of Plant Bacteriology Laboratory - Federal Rural University of Pernambuco were tested. Melon seedlings yellow type 10 days old had their soil infested with 1000 eggs of Meloidogyne incognita race 2. Two days before soil infestation 20 mL of bacterial suspension (0,7 OD) were deposited in each pot. After 60 days fresh biomass of shoot and root , gall index, egg mass index and nematode reproduction factor were determined. Among 117 isolates the endophytic ENM7, ENM10 and ENM51 were selected because they significantly reduced egg mass index and/or gall index. However when tested again, separately or in mixtures, these isolates did not maintain their efficiency and besides they did not affect egg hatching in vitro. In order to study the activity of the isozymes α and β-esterase, peroxidase, acid phosphatase and malate dehydrogenase, plants of melon with 10 days old, had their soil infested with 500 nematode eggs per plant, and maintained in greenhouse. At 2, 4, 6, 8, 16, 24 e 32 days after soil infestation the third leaf of each plant was collected and processed for electrophoresis of isozymes in polyacrilamide gel. Only β-esterase and malate dehydrogenase showed polymorphism between bands expressed by plants parasitized by nematodes when compared to the control plants. The nematode inhibited the expression of some β-esterase genes and activated the expression of other malate dehydrogenase genes. / O objetivo dessa pesquisa foi isolar e selecionar bactérias para o controle da meloidoginose e avaliar a atividade isoenzimática de plantas de meloeiro parasitadas por Meloidogyne incognita raça 2. A partir de solo rizosférico de meloeiro foram obtidos 61 isolados de rizobactérias que juntamente com 56 isolados endofíticos pertencentes à Coleção de Culturas do Laboratório de Fitobacteriologia da UFRPE foram testados. Plântulas de meloeiro Amarelo com 10 dias tiveram o solo infestado com 1000 ovos de M. incognita raça 2. Dois dias antes da infestação do solo foram depositados 20 mL da suspensão bacteriana (0,7 A) por vaso. Decorridos 60 dias, foram determinadas as biomassas frescas da parte aérea e das raízes, os índices de galhas e de massa de ovos e o fator de reprodução do nematóide. Dos 117 isolados testados, foram selecionados inicialmente os endofíticos ENM7, ENM10 e ENM51 que reduziram significativamente o índice de massa de ovos e/ou o índice de galhas. Contudo, quando testados novamente, separadamente ou em misturas, esses isolados não mantiveram a eficiência na redução dessas variáveis e in vitro também não afetaram a eclosão dos juvenis. Para o estudo da atividade das isoenzimas α e β-esterase, peroxidase, fosfatase ácida e malato desidrogenase, plantas de meloeiro com dez dias de idade, tiveram o solo infestado com 500 ovos do nematóide por planta, sendo mantidas em casa de vegetação. Aos 2, 4, 6, 8, 16, 24 e 32 dias após a infestação do solo a terceira folha das plantas foi coletada e submetida à eletroforese de isoenzimas em gel de poliacrilamida. Apenas a β-esterase e a malato desidrogenase mostraram polimorfismo entre as bandas expressas pelas amostras das plantas parasitadas por nematóides, quando comparadas às plantas testemunhas. A presença do nematóide inibiu a expressão de alguns genes β-esterase e ativou a expressão de outros da malato desidrogenase.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-16T14:38:17Z No. of bitstreams: 1 Elineide Barbosa de Souza.pdf: 390725 bytes, checksum: 343f1ce1b17f2c507a8bc4587f0077ac (MD5) / Made available in DSpace on 2017-03-16T14:38:17Z (GMT). No. of bitstreams: 1 Elineide Barbosa de Souza.pdf: 390725 bytes, checksum: 343f1ce1b17f2c507a8bc4587f0077ac (MD5) Previous issue date: 2002-06-28 / The variability of 20 Acidovorax avenae subsp. citrulli isolates in relation to melon fruit blotch components, hypersensitive reaction, and the bacterial transmission by seeds from inoculated fruits were studied. The influence of duration (0, 6, 24 and 48 h), the onset of leaf wetness period (0, 6, 24 and 48 h after inoculation), and inoculum concentration of A. avenae subsp. citrulli (3.4 x 101 to 3.4 x 107 CFU mL-1) on severity of fruit blotch in melon plants were also evaluated. The effects of temperature (15, 20, 25, 30, 35 and 40° C), humidity (0 and 6 h of moist chamber), inoculum concentration (3.4 x 101 to 3.4 x 107 CFU mL-1) and fruit age (40, 50, 60 and 70 days) on the development of melon fruit blotch were also verified. Seeds, plants and fruits were inoculated through vacuum infiltration, atomization and sub-epidermal injection, respectively. Seedlings and plants were assessed in relation to incubation period, diseaseindex, area under disease progress curve and disease progress rate; incubation period, diameter of external lesion and lesion depth were assessed on the fruits. The data were submitted to mean comparison tests, clustering tests or regression analysis. The Euclidian distance–single linkage confirmed the variability among the A. avenae subsp. citrulli strains allowing their separation in four similarity groups. Seed transmission ranged from 30 to 64 % and all strains induced hypersensitive reaction on tobacco and tomato leaves. The regression equations for the analyzed variables in melon plants were better adjusted by the quadratic or logarithmic models. The incubation period ranged from 1.3 to 2.7 days and was higher in plants without leaf wetness, although the disease index and area under disease progress curve increased as the duration of leaf wetness increased. The beginning of the leaf wetness period at 48 h after inoculation elevatedthe incubation period and disease progress rate in relation to the other periods. The disease progress rate, disease index and area under disease progress curve increased as the inoculum concentration increases, reaching maximum values of 4.4 infection units/day, 73.7 % and 18.9 at 3.4 x 107 UFC mL-1, respectively, at 3.4 x 101 CFU mL-1. The temperature and humidity influenced significantly (P=0,05) the severity of melon fruit blotch, however, the incubation period was not affected. The larger external lesions were observed in the fruits incubated at 35 and 30° C without moist chamber, and at 30° C in moist chamber for six h. In relation to lesion depth, those lesions in fruits incubated without moist chamber were deeper at 25 and 30° C. However, with moist chamber the lesions at 30° C were deeper than the others. No disease symptoms were observed onfruits incubated at 15 and 20° C. The humidity significantly (P=0,05) influenced the development of external lesions and lesions depth at 35 and 25° C, respectively. The diameter and depth of lesions increased as the inoculum concentration was higher and were reduced as the fruit age increased. No external or internal lesions were detected on fruits with 60 and 70 days inoculated with the pathogen at 3.4 x 101 CFU mL-1. / Foi estudada a variabilidade de 20 isolados de Acidovorax avenae subsp. citrulli quanto aos componentes da mancha-aquosa do melão e reação de hipersensibilidade, e analisada a transmissão da bactéria pelas sementes dos frutos inoculados. Foi também avaliada a influência da duração (0, 6, 24 e 48 horas) e início do período de molhamento foliar (0, 6, 24 e 48 horas após a inoculação), bem como da concentração de inóculo de A. avenae subsp. citrulli (3,4 x 101 a 3,4 x 107 UFC mL-1) na severidade da mancha-aquosa em meloeiro. A influência da temperatura (15, 20, 25, 30, 35 e 40° C), da umidade (0 e 6 horas de câmara úmida), da concentração de inóculo ( 3,4 x 101 a 3,4 x 107 UFC mL-1) e da idade do fruto (40, 50, 60 e 70 dias) no desenvolvimento da mancha-aquosa em melão, foram ainda verificadas. Sementes, plantas e frutos foram inoculados pelos métodos de infiltração a vácuo, pulverização e injeção subepidérmica, respectivamente. Plântulas e plantas foram avaliadas quanto ao período de incubação,índice de doença, área abaixo da curva do progresso da doença e taxa de progresso da doença, e os frutos, quanto ao período de incubação, diâmetro da lesão externa e profundidade da lesão. Os dados obtidos foram submetidos a testes de comparação de médias, testes de agrupamento ou análises de regressão. A análise da distância Euclidiana por ligações simples, confirmou a variabilidade entre os isolados de A. avenae subsp. citrulli, permitindo a separação destes em quatro grupos de similaridade. A transmissão da bactéria por sementes variou de 30 a 64 % e todos os isolados induziram reação de hipersensibilidade em folhas de fumo e tomate. As equações de regressão para as variáveis analisadas em meloeiros foram melhor ajustadas pelos modelos quadrático ou logarítmico. O período de incubação variou de 1,3 a 2,7 dias, emaior nas plantas sem molhamento foliar, contudo o índice de doença e a área abaixo da curva de progresso da doença aumentaram com o incremento da duração do molhamento foliar. O início do período de molhamento foliar às 48 horas após a inoculação elevou o período de incubação e a taxa de progresso da doença em relação aos demais períodos. O incremento da concentração de inóculo elevou a taxa de progresso da doença, índice de doença e área abaixo da curva de progresso da doença, os quais atingiram valores máximos de 4,4 unidades de infecção/dia, 73,7 % e 18,9, respectivamente, na concentração 3,4 x 107 UFC mL-1. A temperatura e umidade influenciaram significativamente a severidade da mancha-aquosa nos frutos, embora o período de incubação não tenha sido afetado. As maiores lesões externas foram observadas em frutos incubados a 35 e 30 ° C sem câmara úmida, e a 30° C em câmaraúmida por seis horas. Com relação à profundidade, as lesões nos frutos incubados sem câmara úmida foram maiores às temperaturas de 25 e 30° C. Em câmara úmida, as lesões a 30° C foram maiores que as demais. Não foi observado desenvolvimento da mancha-aquosa em frutos incubados a 15 e 20° C. A umidade influenciou significativamente (P=0,05) o diâmetro e profundidade da lesão, exceto às temperaturas de 35 e 25° C, respectivamente. O diâmetro e profundidade das lesões aumentaram com a elevação da concentração de inóculo e foram reduzidos com o aumento da idade do fruto. Na concentração 3,4 x 101 UFC mL-1 não foi observada a presença de sintomas da doença na casca e na polp

Orientador: Antonio Ismael Inácio Cardoso / Banca: Norberto da Silva / Banca: Arlete Marchi Tavares de Melo / Resumo: O objetivo deste trabalho foi avaliar o potencial produtivo de 12 linhagens endogâmicas (S5) obtidas a partir de autofecundações sucessivas de duas populações de pepino japonês, população RY (Rensei x Yoshinari) e população TT (Tsuyataro x Taisho) e de 18 híbridos experimentais obtidos a partir do cruzamento entre linhagens no esquema de dialelo parcial circulante interpopulacional. O experimento foi realizado na Fazenda Experimental São Manuel da FCA/UNESP, Câmpus de Botucatu, no período de março de 2007 a julho de 2008. O delineamento foi em blocos ao acaso, com 33 tratamentos sendo 18 híbridos experimentais, 12 linhagens e três híbridos comerciais, com quatro repetições e cinco plantas por parcela. Foram avaliadas as características produção de frutos imaturos (número e massa) por planta, total e comercial, porcentagem de frutos comerciais, massa média de frutos comerciais, comprimento, diâmetro e relação comprimento/diâmetro dos frutos. As médias foram agrupadas pelo teste de Scott- Knott. Para todas as características de produção obtiveram-se uma linhagem (TT2) e seis híbridos experimentais (H16, H26, H11, H43, H54 e H15) tão ou mais produtivos que o melhor híbrido comercial, Tsuyataro. As heteroses dos híbridos para produção de frutos variaram de -20,90 a 45,33% com predomínio de valores positivos, o que mostrou a superioridade dos híbridos em relação à média dos genitores. / Abstract: The objective of this work was to evaluate the yield potential of 12 inbred lines (S5 ) of two populations of Japanese cucumber: population RY (Rensei x Yoshinari) and population TT (Tsuyataro x Taisho) and 18 experimental hybrids obtained in a diallel partial circling inter population. The experiment was carried out in Experimental Farm São Manuel of FCA/UNESP, Campus Botucatu, in the period from March/2007 to July/2008. The design was randomized blocks, with 33 treatments, 18 experimental hybrids, 12 lines and three commercials hybrids, with four replicates and five plants per plot. The characteristics evaluated were immature fruits yield (number and weight) per plant, total and commercial; percentage of commercial fruits; average weight of commercial fruits; lenght, diameter and relation lenght/diameter of fruits. Treatment means were compared by Scott-Knott test. For all yield characteristics it was obtained a line (TT2) and six experimental hybrids (H16, H26, H11, H43, H54 e H15) as or more yielding than the best commercial hybrid, Tsuyataro. The heteroses of hybrids to yield fruit were from - 20,90 to 45,33%, most of them was positive, showing the superiority of hybrids in relation to parents average. / Mestre

Resumo: Este trabalho avaliou as alterações bioquímicas, fisiológicas, microbiológicas e sensoriais de produtos minimamente processados (PMP) de melão e melancia, utilizando diferentes cortes, embalagens e temperaturas de armazenamento. Melancias 'Crimson Sweet', originárias região de Marília, SP, foram processadas no Laboratório de Tecnologia dos Produtos Agrícolas da UNESP-Jaboticabal, enquanto que melões tipo Orange Flesh, de Mossoró, RN, foram processados no Laboratório de Fisiologia e Tecnologia Pós-Colheita da Embrapa Agroindústria Tropical em Fortaleza, CE. Os frutos depois de lavados com detergente neutro, enxaguados, imersos em água clorada (200mg.L-1) e armazenados em câmara fria (10ºC), por doze horas, tinham a polpa higienicamente cortada em cubos (2,5cm de aresta) e fatias (2,5cm x 2,5cm x 5,0cm), acondicionadas em embalagens plásticas com tampa, copo ou bandeja, ambas de PET, que eram armazenadas a 3ºC e 6ºC. O rendimento da melancia e do melão em PMP foi, respectivamente, de 29-40% e 38-42% em relação ao fruto inteiro. O PMP destes frutos mostrou, nas primeiras 3 horas, aumento na atividade respiratória, que se reduziu e estabilizou, até o final do armazenamento. Isto levou o conteúdo de O2 nas embalagens a se reduzir e o de CO2 a aumentar, durante o armazenamento. A vida útil destes produtos, limitada pela aparência, foi de cinco e sete dias, respectivamente, para a melancia e o melão. A massa fresca, a coloração, a textura, as qualidades sensorial e microbiológica, o pH e os teores de ácido ascórbico, acidez total titulável, sólidos solúveis totais, açúcares solúveis e redutores, mostraram variações pouco expressivas. / Abstract: This work aimed to evaluate the biochemical, physiological, microbiological and sensorial quality of melon and watermelon fruits minimally processed (MP), using different cutting types, packages and storage temperatures. 'Crimson Sweet' watermelons from orchards of Marília, SP were processed at the Laboratório de Tecnologia dos Produtos Agrícolas da UNESP-Jaboticabal, while type Orange Flesh melons from Mossoró, RN were processed at the Laboratório de Fisiologia e Tecnologia Pós-Colheita da Embrapa Agroindústria Tropical em Fortaleza, CE. Fruits after washing with neutral detergent, rinsed and dipped in chlorinated water (200 mg.L-1) were stored at 10oC, in previously hygienized chamber, for 12 hours. The flesh was hygienically cut in cubes (2,5 cm) and slices (2,5 x 2,5 x 5,0 cm), and conditioned in plastic packages, glass or tray with lids, a made of polyethylene terephthalate (PET), and stored at 3oC and 6oC. Watermelon and melon yield in fruits MP were 29-37% and 38-42%, respectivelly, in relation to whole fruit. These fruits MP showed, in first 3 hours, increase in respiratory rate followed by reduction and stabilization until the end of storage. The effect was a reduction of O2 and an increase of CO2 content inside the packages, during storage. The shelf life of these products were five and seven days, respectivelly for watermelon and melon, with appearance development as the limiting factor. The fresh weight loss, color, firmness, sensorial and microbiological qualities, pH and content of ascorbic acid, total titratable acidity, soluble solids, soluble and reducing sugars, showed variations with little significance. / Orientador: José Fernando Durigan / Coorientador: Ricardo Elesbão Alves / Banca: Arthur Bernardes Cecilio Filho / Banca: Ricardo Klüge / Mestre

Thesis (M.Agric. (Horiticulture)) --Unversity of Limpopo, 2013 / The ground leaching technology (GLT) system, using crude extracts of wild cucumber (Cucumis myriocarpus) and wild watermelon (Cucumis africanus) fruits, had been widely researched and developed in management of the root-knot (Meloidogyne species) nematodes in tomato (Solanum lycopersicon) production. In the GLT system, experiments were harvested at 56 days after inoculation with nematodes, which was approximately three generations of Meloidogyne species. Also, studies in GLT systems demonstrated that effective micro-organisms (EM) were not essential in the release of chemicals from crude extracts for nematode suppression, with suggestions that the system exclusively relied upon irrigation or rainwater for leaching out chemicals. However, the system had hardly been tested on other nematode species with longer life cycles and crops. The objective of this study was to investigate the influence of crude extracts of C. myriocarpus (cucurbitacin A-containing phytonematicide) and C. africanus (cucurbitacin B-containing phytonematicide) with and without EM on suppression of population densities of the citrus nematode (Tylenchulus semipenetrans) on rough lemon (Citrus jambhiri) over three generations of the nematode. Two studies, one on C. myriocarpus and the other on C. africanus, with and without EM, were conducted separately using the GLT system under greenhouse conditions with three generations of T. semipenetrans as the standard of application interval of the materials. Citrus seedlings were transplanted in 7-L plastic pots contain 6.5-L pasteurised river sand and Hygromix (3:1 v/v) and inoculated with approximately 25 000 second-stage juveniles (J2s) in 2 × 2 × 2 factorial experiment, where treatments were arranged in a randomised complete block design (RCBD), with six replications. At 150 days after treatment, nematode and plant variables were collected and subjected to factorial analysis of variance. Under C. myriocarpus (Cm), EM × Cm interaction was not significant for nematodes (juveniles + eggs) in roots and juveniles in soil, while under C. africanus (Ca), EM × Ca interaction was highly significant for nematodes, but not for juveniles. Crude extracts of C. myriocarpus and C. africanus fruits contributed 21-36% and 38-59% to total treatment variation in nematodes, respectively. Relative to untreated control, crude extracts of C. myriocarpus fruit reduced nematodes by 22% in roots, but increased juveniles in soil by 93%. Similarly, C. africanus fruit reduced nematodes in roots by 80%, but increased juveniles in soil by 178%. The increase of juveniles in the soil was explained on the basis of opposing forces on nematode population densities under crude extracts of Cucumis and untreated control, along with the inherent nature of cyclic population growth in plant-parasitic nematodes. In plant variables, certain significant (P ≤ 0.05) interactions consistently occurred under both Cucumis species. However, effects of the interactions were not consistent under the two Cucumis species. In most of the variables, the non-significant effects of EM × Cm interactions supported the view that the GLT systems were independent of microbial activities, while significant (P ≤ 0.05) EM × Ca interactions suggested that the systems under C. africanus fruit could be viewed as being dependent upon microbial degradation activities. Growth of rough lemon rootstock was, to a certain extent, suppressed by application of crude extracts from Cucumis fruits, suggesting that the material were phytotoxic to this citrus rootstock. Under low nematode population densities, T. semipenetrans infection supported the view that nematode numbers below the damage threshold levels have stimulatory effects on growth of plants as observed in plant height under conditions of this study. In conclusion, the approximately three nematode-generation-application interval of 150 days for crude extracts of fruits in Cucumis species was rather too long for the efficacies of the materials on suppression of the population densities of T. semipenetrans in rough lemon seedlings. Consequently, shorter application intervals, as demonstrated for Meloidogyne species would be appropriate, although caution has to be taken to ensure that phytotoxicity to the rootstock was avoided.

Thesis (Ph.D. Agriculture (Horticulture)) -- University of Limpopo, 2012 / High yield losses in various crops due to plant-parasitic nematodes are associated with high initial nematode population densities (Pi). Uses of synthetic nematicides to reduce Pi were dependent on the physiological effect of materials on the protected crops, resulting into the coining of pre-emergent and post-emergent nematicides. Crude extracts of wild cucumber (Cucumis myriocarpus) fruit consistently reduced nematode population densities of the southern root-knot nematode (Meloidogyne incognita) when used as a post-emergent bio-nematicide. The purpose of this study was to investigate the compatibility of crude extracts of C. myriocarpus fruit when used as a pre-emergent bio-nematicide on germination and emergence of commercially important dicotyledonous and monocotyledonous crops using empirical tests and computer-generated models. Studies were conducted over a period of three years to assess the effects of this material on growth of various seedlings. Seven treatments comprising crude extracts of C. myriocarpus fruit (0, 2.5, 5, 7.5, 10, 12.5 and 15 g/pot) and test solutions (0, 25, 50, 75, 100, 125 and 150 g/ℓ distilled water) were used for emergence and germination in initial studies. Generally, 18 days after the treatments, variables measured and levels of crude extracts of C. myriocarpus fruit had negative quadratic relationships, which suggested that they had density-dependent growth responses. Subsequent studies were conducted using three selected crops each from the families Alliaceae, Gramineae and Solanaceae under greenhouse conditions, each with reduced concentration of 10 treatments (0, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00 and 2.25 g material/pot). Using variables of various organs and crops, significant means were subjected to the Curve-fitting Allelochemical Dosage Response (CARD) computer model, which was characterised by six biological indices, viz. threshold stimulation (Dm), xli saturation level (Rh), 0% inhibition (D0), 50% inhibition (D50), 100% inhibition (D100) and transformation level (k). The model demonstrated that the responses of the three crops from each family when regressed to dosages of crude extracts of C. myriocarpus fruit exhibited the density-dependent growth patterns, characterised by responses that included stimulation, saturation and inhibition. The integrated sensitivities (Σk) of the tested crops to crude extracts of C. myriocarpus fruit ranged from Σk = 9 to Σk = 51, with eggplant (Solanum melongena) and sorghum (Sorghum bicolor) being the most sensitive, while tomato (Solanum lycopersicum) was the least sensitive. Using the data depicting the stimulation range from CARD model, viz. (Dm), which is a threshold stimulation dosage and (Rh), which is a saturation dosage, mean dosage stimulation response (MDSR) was determined for chive (Allium schoenoprasum), leek (Allium ampeloprasum), onion (Allium cepa), maize (Zea mays), millet (Panicum miliaceum), sorghum, eggplant, pepper (Capsicum annum) and tomato as being 1.19, 0.68, 0.45, 1.13, 0.86, 1.12, 0.74, 1.11, and 0.53 g, respectively. These MDSR values are dosages which when applied for respective crops at direct seeding would not affect germination or emergence. MDSR values were validated for onion, millet and tomato, resulting in approximately 100% suppression of nematodes in all three test crops. In contrast, 100% emergence occurred in millet and tomato, while the validated MDSR reduced emergence on onion by 15%, which confirmed the sensitivity of this crop to crude extracts of C. myriocarpus fruit. In conclusion, crude extracts of C. myriocarpus fruit have the potential for use as pre-emergent bio-nematicide in suppression of plant-parasitic nematodes in various crops.