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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Estudo do extrato pirolenhoso Biopirol® no manejo de nematóides em cana-de-açúcar, olerícolas e citros, em diferentes ambientes /

Corbani, Renato Zapparoli. January 2008 (has links)
Resumo: No Japão, uma solução aquosa, referida como extrato pirolenhoso, resultante da carbonização de madeira ou bambu, obtida através da condensação da fumaça, vem sendo estudada com fins agrícolas, inclusive como alternativa para os defensivos químicos convencionais. O presente estudo teve como objetivo avaliar a ação do extrato pirolenhoso Biopirol® sobre a eclosão e a atividade de juvenis de segundo estádio de Meloidogyne incognita, Meloidogyne. javanica e Tylenchulus semipenetrans, sobre o manejo de populações de nematóides, a campo, em cana-deaçúcar e citros, e em alface sob ambiente protegido. No Laboratório de Nematologia do Departamento de Fitossanidade da Universidade Estadual Paulista, Câmpus de Jaboticabal, foram preparadas câmaras de eclosão para a avaliação do extrato pirolenhoso Biopirol®, em diferentes concentrações, variando de 0,5% até 2,0%, sobre a eclosão e atividade dos nematóides in vitro. Nos experimentos a campo, as concentrações do produto variaram de 0,5% até 8,0%. Os dados foram submetidos à análise de variância, e as médias foram comparadas pelo Teste de Tukey, a 5% de probabilidade. Os resultados evidenciaram que o extrato pirolenhoso Biopirol® reduz a eclosão de juvenis de M. incognita, de M. javanica e de T. semipenetras in vitro e a formação de galhas formadas por M. incognita e por M. javanica em raízes de tomateiro. Nas concentrações de até 4%, não foi eficaz para a redução da população de Pratylenchus zeae e Meloidogyne sp. em cana-de-açúcar e de T. semipenetrans em laranjeira "Natal' enxertada sobre limoeiro cravo. Nas concentrações de até 8,0%, também, não foi eficaz para a redução da população de Rotylenchulus reniformis e M. incognita em alface 'Lucy Brown', em ambiente protegido. / Abstract: In Japan, an aqueous solution resulting from the carbonization of wood or bamboo, obtained by the condensation of smoke, referred to as pyroligneous acid has been studied with agricultural purposes, including as an alternative to the conventional chemical control of pests and diseases. This study aimed to evaluate the effect of the pyroligneous acid Biopirol® on the hatching and activity of second stage juvenile of Meloidogyne incognita, M. Javanica and Tylenchulus semipenetrans; as well as on the management of populations of nematodes, at field conditions in sugar cane and citrus and lettuce under protected environment. In Nematology Laboratory of the Department of Plant Protection of the Universidade Estadual Paulista, Câmpus of Jaboticabal, hatching chambers were prepared for the evaluation of different concentrations ranging from 0.5 % until 2.0 % of the pyroligneous acid Biopirol® on the hatching and activity of the nematodes in vitro. In the field experiments, the concentrations of the product ranged from 0.5% to 8.0%. The data were submitted to the analysis of variance and the means were compared by Tukey test of a 5% probability. Results showed that the pyroligneous acid Biopirol® reduces the hatching of the second stage juveniles of Meloidogyne incognita, M. Javanica and Tylenchulus semipenetrans in vitro. Also, reduces the formation of galls by M. incognita and M. Javanica in roots of tomato. At the concentrations of up to 4% was not effective in reducing the population of Pratylenchus zeae and Meloidogyne sp. in sugar cane and of Tyelenchulus semipenetras in orange cv. Natal grafted on Rangpur lime. In concentrations of up to 8,0% has not been effective in reducing the population of Rotylenchulus reniformis and M. incognita in lettuce cv. Lucy Brown in protected environment. / Orientador: Jaime Maia dos Santos / Coorientador: Jairo Osvaldo Cazetta / Banca: Rita de Cássia Panizzi / Banca: Júlio Cesar Galli / Banca: Clélia Aparecida Iunes Lapera / Banca: Fábio Mazzoneto / Doutor
62

Estudos histopatológicos e ciclos biológicos de Meloidogyne mayaguensis e M. javanica em tomateiros com gene Mi /

Westerich, Juliana Nogueira, 1983- January 2010 (has links)
Resumo: A espécie Meloidogyne mayaguensis vem causando grande preocupação por ser capaz de vencer a resistência de tomateiros portadores do gene Mi. O objetivo do trabalho foi estudar o ciclo biológico e a histopatologia de M. mayaguensis em tomateiros resistentes a meloidoginose e compará-los com os aspectos biológicos e histopatológicos de Meloidogyne javanica nas mesmas plantas. O delineamento experimental utilizado foi inteiramente casualizado, sendo para o estudo do ciclo biológico composto de vinte tratamentos (dois porta-enxertos de tomateiro, 'Magnet' e 'Helper M'; duas espécies de nematoides das galhas, M. mayaguensis e M. javanica; e cinco épocas de coleta, 3 DAI, 10 DAI, 17 DAI, 24 DAI e 31 DAI), com cinco repetições. Para o estudo da histopatologia, composto por 12 tratamentos (dois porta-enxertos de tomateiro, 'Magnet' e 'Helper M'; duas espécies de nematoides das galhas, M. mayaguensis e M. javanica; e três épocas de coleta, 10 DAI, 17 DAI e 24 DAI), com três repetições. As plantas foram inoculadas com 500 juvenis infectivos (J2) de M. mayaguensis ou M. javanica. As avaliações foram realizadas em cinco épocas de coleta. Em cada coleta, cinco plantas foram retiradas ao acaso e suas raízes separadas em duas porções. Uma das partes foi submetida à coloração com Fucsina Ácida e dissecada sob microscópio estereoscópico para a contagem dos diferentes estádios de desenvolvimento dos nematoides. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Na outra porção do sistema radicular, foram feitos cortes histológicos transversais com 8 μm de espessura, corados com Floxina B seguido de Azul de Toluidina 0,05%, para determinação dos números e áreas das células gigantes e dos sítios de alimentação presentes no cilindro vascular da raiz. Os dados obtidos foram submetidos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The species Meloidogyne mayaguensis is causing great concern for being able to overcome the resistance of tomatoes carrying the Mi gene. The objective of this work was to study the life cycle and the histopathological changes of M. mayaguensis in nematode-resistant tomatoes and compare them with biological and histopathological aspects of Meloidogyne javanica in the same plants. The experimental design was completely randomized, and to study the life cycle composed of twenty treatments (two varieties of tomato, 'Magnet' and 'Helper M', two species of nematodes, M. javanica and M. mayaguensis and five harvest dates, 3 DAI, 10 DAI 17 DAI 24 DAI and 31 DAI), with five replicates. To study the histopathology, composed of 12 treatments (two varieties of tomato, 'Magnet' and 'Helper M', two species of nematodes, M. javanica and M. mayaguensis and three harvest dates, 10 DAI, 17 DAI and 24 DAI), with three replications. The plants were inoculated with 500 infective juveniles (J2) of M. mayaguensis or M. javanica. The evaluations were conducted in five sampling times. At each harvest, five plants were taken at random and their roots separated into two parts. The first was stained with Acid Fuchsin and dissected under a stereomicroscope to count the different developmental stages of nematodes. The data were subjected to analysis of variance and means compared by Tukey test at 5% probability. In the another portion of the root system, 8 microns thick transversal sections were obtained, stained with Phloxine B followed by Toluidine Blue 0.05%, for determining the numbers and areas of giant cells and feeding sites in the vascular cylinder. The data were subjected to Multivariate Cluster Analysis and Principal Component Analysis. The results showed that the species M. mayaguensis was able to develop normally in the root-stocks, completing its cycle 24 days after inoculation (DAI)... (Complete abstract click electronic access below) / Orientador: Silvia Renata Siciliano Wilcken / Coorientador: Roberto Antonio Rodella / Banca: Rosana Bessi / Banca: Francisco Andre Ossamu Tanaka / Mestre
63

Exsudatos de sementes de soja [Glycine max (L.) Merrill]: caracterizaÃÃo proteÃmica e efeitos contra o nematoide das galhas Meloidogyne incognita / Exudates of soybean [Glycine max (L.) Merrill]: proteomic characterization and effects against root-knot nematode Meloidogyne incognita

Raquel de Oliveira Rocha 08 May 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A exsudaÃÃo à um mecanismo de defesa apresentado por sementes que consiste na liberaÃÃo de molÃculas para o solo durante o processo de germinaÃÃo. Esses exsudatos, compostos essencialmente de proteÃnas e metabÃlitos secundÃrios, atuam interferindo no desenvolvimento de microrganismos, representando fontes para prospecÃÃo de molÃculas de defesa com potencial biotecnolÃgico, voltadas ao controle de patÃgenos de solo. Nesse contexto, a soja se destaca [Glycine max (L.) Merrill] como sistema ideal ao estudo das interaÃÃes planta-patÃgeno, visto seu grande valor econÃmico e o alto teor de proteÃnas de seus grÃos. Este trabalho teve como objetivos caracterizar a composiÃÃo dos exsudatos de sementes de dois cultivares de soja, com diferentes Ãndices de desempenho em resposta ao nematoide das galhas Meloidogyne incognita, e avaliar seus efeitos in vitro e in vivo sobre este fitopatÃgeno. Exsudatos foram obtidos a partir de sementes de soja (cultivares BRS-Pala: suscetÃvel; BRS-Macota: resistente), embebidas em acetato de sÃdio 0,1 M, pH 5,0, por 18 horas. A anÃlise proteÃmica comparativa livre de gel que permitiu a identificaÃÃo de diversas proteÃnas relacionadas à defesa vegetal, tais como a aglutinina da soja, os inibidores de tripsina do tipo Kunitz e Bowman-Birk e proteÃnas relacionadas à patogÃnese. A anÃlise qualitativa de metabÃlitos secundÃrios nos exsudatos revelou a presenÃa de fenÃis, triterpenÃides, saponinas, flavonas, flavonÃis e xantonas em ambas as cultivares. Posteriormente, estes exsudatos foram dialisados em membranas de diÃlise com exclusÃo de 3,5 kDa e submetidos à dosagem de proteÃnas bioativas. As atividades hemaglutinante (609,52 UH/mgP), inibitÃrias de tripsina (4,81 mg tripsina inibida/mgP) e papaÃna (30,48 UI/mgP), proteolÃtica (1,52 UAPr/mgP.min) e β-1,3-glucanÃsica (58,26 ηkatGLU/mgP) foram maiores para a cultivar BRS-Pala. Jà a atividade peroxidÃsica (0,218 UAP/mgP.min) predominou na cultivar BRS-Macota, A avaliaÃÃo da atividade nematicida sobre ovos e juvenis de segundo estÃdio (J2), usando exsudatos dialisados, revelou que ambos os exsudatos sÃo capazes de inibir a eclosÃo de M. incognita, bem como a mobilidade dos juvenis desta espÃcie. Esta propriedade nematostÃtica se reflete na infectividade do parasita, reduzida pelo tratamento com proteÃnas exsudadas na concentraÃÃo de 0,13 mg/mL. Os resultados reforÃam a ideia de que a exsudaÃÃo das sementes està relacionada à defesa constitutiva deste ÃrgÃo vegetal, sugerindo que proteÃnas presentes nos exsudatos podem promover proteÃÃo contra nematoides durante o processo germinativo. / Exudation is a defense mechanism presented by seeds, which release molecules to the soil during the germination process. These exudates, mainly composed by proteins and secondary metabolites, act interfering with the development of microorganisms. They represent a source of defense molecules with biotechnological potential to control soil-borne pathogens. In this context, soybean [Glycine max (L.) Merrill] stands as an ideal system in the study of plant-pathogen interaction due to its great economic value and the high content of seed proteins. The experimental activities presented in this thesis aimed to characterize the composition of seed exudates from two different soybean cultivars, which show different levels of performance in response to the root-knot nematode Meloidogyne incognita. Furthermore, the in vitro and in vivo effects of the seed exudates on this pathogen were evaluated. For this purpose, the exudates were obtained from soybean seeds (BRS-Pala:susceptible; BRS-Macota:resistant), soaked in 0.1 M sodium acetate, pH 5.0, during 18 hours. The gel-free proteomic analysis allowed identification of several defense-related proteins such as soybean agglutinin, Kunitz and Bowman-Birk trypsin inhibitors, and pathogenesis-related proteins. The qualitative analysis of secondary metabolites in the exudates also revealed the presence of phenols, triterpenoids, saponins, flavones, flavonols, and xanthones in both cultivars. The above exudates were dialyzed in 3.5 kDa cut-off membranes and assayed for bioactive proteins. The hemagglutinating (609.52 HU/mgP), trypsin (4.81 mg trypsin inhibited/mgP) and papain (30.48 IU/mgP) inhibitor, proteolytic (1.52 UAPr/mgP.min), and β-1, 3-glucanase (58.26 ηkatGLU/mgP) activities were higher for BRS-Pala. Otherwise, the peroxidase activity (0.218 UAP/mgP.min) predominated in BRS-Macota. The evaluation of anti-nematode activity against eggs and second stage juveniles (J2) revealed that both exudates were able to inhibit the hatching of M. incognita eggs as well as the J2 mobility. This nematostatic property is reflected in the infectivity of the parasite, reduced by the exuded protein at 0.13 mg/mL concentration. The results reinforce the idea that the exudation is related to the constitutive defense of the seeds, suggesting that the proteins present in the exudates can contribute to the protection against nematodes and possibly other plant enemies during the germination process.
64

AnÃlise proteÃmica de raÃzes de feijÃo-de-corda (Vigna unguiculata), CV. CE-31, inoculadas com o nematÃide das galhas (Meloydogine incognita) / Proteomics analysis of cowpea roots (Vigna unguiculata), CV. CE-31, inoculated with root-knot nematode (Meloydogine incognita)

Josà HÃlio de AraÃjo Filho 15 September 2011 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O feijÃo-de-corda [Vigna unguiculata (L.) Walp.] à uma importante leguminosa usada como alimento, sendo cultivada, primariamente, nas savanas secas do Continente Africano, na Ãsia e na AmÃrica do Sul, cobrindo mais de 12 milhÃes de hectares, com produÃÃo anual de cerca de 3 milhÃes de toneladas. O feijÃo-de-corda se constitui numa cultura de extrema importÃncia em zonas semi-Ãridas dos trÃpicos, caracterizadas por baixa precipitaÃÃo pluviomÃtrica, altas temperaturas, solos arenosos e de baixa fertilidade. Dentre os organismos que causam doenÃas nos vegetais, os nematÃides geram prejuÃzos anuais de, aproximadamente, vÃrios bilhÃes de dÃlares na agricultura mundial e as espÃcies Meloidogyne incognita e Meloidogyne javanica sÃo as mais danosas. Uma das principais culturas atacadas pelos nematÃides à o feijÃo-de-corda. Em funÃÃo disso, existe sempre demanda para se buscar melhorar a compreensÃo dessa relaÃÃo entre hospedeiros e patÃgenos objetivando criar novas estratÃgias para minimizar eventuais perdas. O presente trabalho teve como objetivo identificar as proteÃnas que tÃm sua expressÃo diferenciada em raÃzes de feijÃo-de-corda resistente ao Meloidogyne incognita (inoculadas e nÃo inoculadas) usando eletroforese bidimensional (2D) associada à espectrometria de massas de proteÃnas extraÃdas da raiz total e de mitocÃndrias de raiz do cv PitiÃba (CE-31), resistente ao nematÃide, inoculada com este patÃgeno, em comparaÃÃo com plantas nÃo-inoculadas (controle) em conjunto com anÃlise de expressÃo gÃnica semi-quantitativa (PCR semi-quantitativa). Os resultados aqui obtidos demonstraram que houve alteraÃÃo de pelo menos 22 proteÃnas nas amostras de raÃzes inoculadas e mais 22 proteÃnas de mitocÃndrias de raÃzes, quando comparados com seus respectivos controles e que o Ãpice das suas alteraÃÃes ocorriam por volta do 6 dia apÃs a inoculaÃÃo do patÃgeno. As proteÃnas de mitocÃndrias nÃo puderam ser identificadas com confiabilidade. Dentre as proteÃnas de raÃzes totais identificadas podemos destacar as PR-1, 2 e 3, que sÃo reconhecidamente proteÃnas de defesa, ascorbato peroxidase e superÃxido dismutase (enzimas anti-estresse oxidativo) e uma leghemoglobina, que pode ser o primeiro relato dessa proteÃna nesse patossistema. As anÃlises de expressÃo gÃnica concordaram perfeitamente com os achados proteÃmicos. / The cowpea [Vigna unguiculata (L.) Walp.] is an important leguminous used as food, being cultivated, mostly in arid African savannas , Asia and south of America, covering more over 12 millions of hectares, with annual production about 3 millions of tons. The cowpea itâs a culture greatly important in tropics zones characterized by low pluviometric precipitation, high temperature , gravely soils and poor fertility. Among the pathogenic organism that cause plant disease, the nematode, mainly Meloydogine sp. generate annual losses about several billions of dollars all over the world and the Meloidogyne incognita and Meloidogyne javanica species be the most damagers. One of the main cultures attacked by nematodes is the cowpea. Regard it, there is always needs to improve the knowledge about the relationship between host and pathogens aimed develop novels strategies to diminish eventual losses. The present work aimed identify the differential expression of proteins in Meloidogyne incognita resistant cowpea total roots and mitochondria roots cv PitiÃba (CE-31), inoculated and mock inoculated, using 2D electrophoresis assay associated with MS identification and gene expression analyses by semi-quantitative PCR. The results obtained showed at least 22 altered proteins in inoculated total roots and more 22 proteins of mitochondria roots, when compared with their respective controls and the top of alterations occurred next to 6 day after inoculation with pathogen. Mitochondria proteins cannot be identified reliability. Among the total roots proteins we can emphasize PR-1, 2 and 3, recognized as defense proteins, ascorbate peroxidase and superoxide dismutase (anti-oxidative brush enzymes) and a leghemoglobin, which can be the first report about this protein in this pathosystem. The gene expression analyses coincided with proteomics finds.
65

Comportamento de genótipos RB de cana-de-açúcar a nematoide das galhas e avaliação dos mecanismos de resistência envolvidos

SILVA, Matheus Silva e 31 July 2015 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-12-05T12:55:30Z No. of bitstreams: 1 Matheus Silva e Silva.pdf: 927208 bytes, checksum: b577e7fbf3a3419012f5dc12beda0cda (MD5) / Made available in DSpace on 2016-12-05T12:55:30Z (GMT). No. of bitstreams: 1 Matheus Silva e Silva.pdf: 927208 bytes, checksum: b577e7fbf3a3419012f5dc12beda0cda (MD5) Previous issue date: 2015-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / One of the most economic importance crops in Brazil, the sugarcane (Saccharum spp.) cultivation is severely affected by several biotic and abiotic factors. Within the biotic one the damage caused by Meloidogyne species points out due to lesions in parasite roots resulting in decreases of productivity. The non-availability of root-knot nematode resistant varieties becomes more serious after reduction in nematicides use, increasing efforts in turn resistant varieties a possible alternative. Therefore, the objectives of the present work was screening promising sugarcane genotypes for M. incognita and M. javanica resistance (Study 1) and determine the resistance mechanisms involved through evaluation of penetration, development and reproduction of the nematodes in the selected material (Study 2), under greenhouse. In Study 1, evaluations were carried out 120 days after inoculation with 9000 eggs per plant and based on host development and nematode reproduction. There was significant difference (P≤0.05) within genotypes for all plant development and nematode reproduction variables. Although all genotypes were susceptible (FR≥1.0) to M. incognita and M. javanica, in some of them the reproductive factor (FR) was lower than the control. In Study 2, five genotypes were inoculated with 20000 eggs per plant and evaluations carried out at 5, 10, 15, 20, 40 and 60 days after inoculation. There was difference in nematode penetration among genotypes, and despite juveniles of both nematode species penetrated all genotypes at five days after inoculation, nematode development significantly differed among clones. At 60, but 45, days after inoculation eggs were evident in the genotypes. Reduced penetration and development rates were demonstrate by the genotypes RB041594 e RB071095. / De relevante importância econômica para o Brasil, o cultivo da cana-de-açúcar (Saccharum spp.) sofre grande influência de diversos fatores bióticos e abióticos. Dentre os bióticos, destacam-se os danos causados por espécies de Meloidogyne, devido às lesões nas raízes parasitadas, resultando em redução de produtividade. A não disponibilidade de variedades resistentes aos nematoides das galhas tornou-se mais séria com a redução do uso de nematicidas, intensificando os esforços para tornar a resistência varietal uma alternativa possível. Dessa forma, o objetivo do presente estudo foi selecionar genótipos RB de cana-de-açúcar promissores para o desenvolvimento de variedades resistentes a M. incognita e M. javanica (Estudo 1) e determinar os mecanismos de resistência envolvidos avaliando-se a penetração, desenvolvimento e reprodução das espécies de nematoides no material selecionado (Estudo 2), em condições de casa de vegetação. No estudo 1, as avaliações foram realizadas 120 dias após a inoculação com 9000 ovos por planta e fundamentaram-se no desenvolvimento do hospedeiro e na reprodução dos nematoides. Houve diferença significativa (P≤0,05) entre os genótipos RB para todas as variáveis de desenvolvimento da planta, e para ambas as espécies de Meloidogyne. Todos os genótipos foram suscetíveis (FR≥1,0) à M. incognita e M. javanica, entretanto, em alguns o fator de reprodução foi inferior ao do tratamento controle. No Estudo 2, cinco genótipos foram inoculados com 20.000 ovos por planta e as avaliações realizadas aos 5, 10, 15, 20, 40 e 60 dias após a inoculação. Houve diferença entre os genótipos avaliados com relação à penetração de juvenis de segundo estádio. Cinco dias após a inoculação foi visualizado juvenis no interior das raízes de todos os tratamentos, mas o desenvolvimento dos nematoides diferiu significativamente entre os clones. Aos 45 dias após a inoculação não foi evidenciada a presença de ovos em nenhum dos genótipos testados, o que só ocorreu aos 60 dias após a inoculação. Reduzidas taxas de penetração e desenvolvimento foram demonstradas pelos genótipos RB 041594 e RB071095.
66

Resistência em genótipos segregantes de Psidium guajava L. à Meloidogyne enterolobii / Resistance in segregating genotypes of psidium guajava L. to meloidogyne enterolobii

Vieira, Alessandra Abreu Rodrigues 08 August 2011 (has links)
Made available in DSpace on 2016-12-23T14:37:44Z (GMT). No. of bitstreams: 1 Alessandra Abreu Rodrigues Vieira.pdf: 310728 bytes, checksum: 0e9cc138bfaeaf0b6e9c447ce14acf80 (MD5) Previous issue date: 2011-08-08 / Neste trabalho, avaliou-se a resistência da goiabeira Psidium guajava L. a Meloidogyne enterolobii (sin. M. mayaguensis) em condições de casa de vegetação. Foram estudados 16 genótipos segregantes, de ocorrência espontânea, coletados nos municípios de Alegre (ES) e Caparaó (MG). O experimento foi conduzido em delineamento inteiramente casualizado, seguindo o esquema fatorial com 16 genótipos x 3 concentrações (500, 2.000 e 4.000 ovos + J2 de Me) e 6 repetições. Os genótipos foram constituídos de plantas oriundas de frutos coletados em plantas matrizes nativas da região. As sementes foram retiradas desses frutos, semeadas e as plantas originadas de cada genótipo foram inoculadas aos seis meses com diferentes concentrações de inóculo. Avaliou-se a altura de plantas (ALT) aos 90 dias após a inoculação e aos 135 foram realizadas as análises de massa fresca de raiz (MFR), número de galhas (NG) e população final (PF) do nematoide. A classificação das progênies quanto à resistência foi realizada pelos critérios proposto por Oostenbrink (1966) e Moura e Régis (1987), ambos baseados no fator de reprodução (FR). Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott e Knott, a 5 % de probabilidade. Os genótipos 5, 6 e 7 apresentaram valores de médias para FR<1 pela classificação de Oostenbrink (1966), assim como dentro das famílias encontrou-se indivíduos com valores de FR<1. Foram encontrados nas progênies dos genótipos 1, 4, 9, 10, 12, 13 e 14 valores de FR<1, o que demonstrou a segregação de genes para resistência em progênies de plantas matrizes suscetíveis. Nos genótipos 2, 3, 8, 11, 15 e 16, todas as progênies apresentaram FR>1 sendo considerados suscetíveis de acordo com critérios de Oostenbrink (1966) e algumas progênies com resistência moderada de acordo com Moura e Régis (1987). Esses resultados permitiram inferir sobre a existência de genes de resistência em P. guajava a M. enterolobii. Houve pouca variação dentro de progênies dos genótipos 2, 4, 5, 6, 7, 9, 10, 12 e 16 para as variáveis MFR, NG e PF, referente ao nível de 500 ovos + J2 de M. enterolobii, os quais se encontram sempre dentro do mesmo grupo de médias que não diferem entre si, mostrando maior homogeneidade desses genótipos quanto à reação ao nematoide. O genótipo 15 apresentou baixos valores de MFR e altos valores de NG e PF nas três concentrações de inóculo, o que demonstrou uma tendência desse genótipo ao parasitismo e reprodução do M. enterolobii / In this work, it was evaluated the resistance of the guava tree Psidium guajava L. to Meloidogyne enterolobii (syn. M. mayaguensis) in green house conditions. Were studied 16 segregating genotypes of spontaneous occurrence collected in the cities of Alegre (ES) and Caparaó (MG). The experiment was conducted in completely randomized design (CRD), following the factorial scheme with 16 genotypes x 3 concentrations (500, 2.000 e 4.000 eggs + J2 of Me) and 6 repetitions. The genotypes were constituted of plants from fruits collected in mother plants native of the region. The seeds were removed of these fruits, sown and the plants originated from each genotype were inoculated with six months old in different concentrations of inoculum. It was evaluated the plants height (ALT) at 90 days after inoculation and at 135 were realized the analysis of fresh weight of root (MFR), number of galls (NG), and final population (PF) of the nematode. The classification of progenies for resistance was carried out by the criteria proposed by Oostenbrink (1966) and Moura and Regis (1987), both based on the reproduction factor (FR). Data were submitted to the analysis of variance and the means compared by the Scott and Knott test in 5% of probability. The genotypes 5, 6 and 7 had mean values for FR<1 by the Oostenbrink (1966) classification, as well as within the families were found individuals with values of FR<1. Were found in the progenies of the genotypes 1, 4, 9, 10, 12, 13 and 14 values of FR<1, what showed the segregation of genes to resistance in progenies of mother plants susceptibles. In the genotypes 2, 3, 8, 11, 15 and 16, all the progenies had FR>1, being considered susceptible in accord with the criteria of Oostenbrink (1966) and some progenies with moderate resistance in accord with Moura e Régis (1987). These results allowed infer about the existence of resistance genes in P. guajava to M. enterolobii. There was little variation within the progenies of the genotypes 2, 4, 5, 6, 7, 9, 10, 12 and 16 for the variables MFR, NG, and PF, on the level of 500 eggs + J2 of M. enterolobii, which are always within the same group averages that do not differ from each other, indicating greater homogeneity of these genotypes for reaction to the nematode. The genotype 15 showed low values of MFR and high values of NG and PF in the three concentrations of inoculum, what indicated a trend of this genotype to the parasitism and reproduction of M. enterolobii
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Communautés de nématodes phytoparasites associés à l'olivier : réponse aux forçages anthropiques et environnementaux / Plant-parasitic nematodes communities associated to olive trees : response to anthropogenic environmental and forcings

Ali, Nadine 08 October 2015 (has links)
Les interventions humaines de plus en plus fréquentes et persistantes dans les écosystèmes d'une part, et l'intensification des systèmes de cultures d'autre part qui s'accompagne pour partie de méthodes radicales pour combattre les bio-agresseurs des cultures, nous posent de multiples questions au sujet des risques écologiques liés aux changements des milieux, dont les perturbations induites sur les communautés d'organismes vivants. Les nématodes phytoparasites (NPP), vers ronds microscopiques telluriques qui occasionnent des pertes de production végétale importantes, sont partout présents en communautés. Ces nématodes répondent rapidement aux forçages extérieurs (e.g. anthropiques et environnementaux) par des modifications de la structure de leurs communautés. Par ce travail de thèse, nous cherchons à mieux comprendre l'effet des facteurs impliqués dans l'assemblage des espèces de NPP en communautés associées à l'olivier méditerranéen et à déterminer la réponse de ces communautés aux forçages imposés par la domestication de l'olivier, par l'intensification de sa culture et par différents facteurs environnementaux. L'étude a été réalisée au Maroc dans toutes les régions oléicoles (vergers traditionnels à faible densité et vergers à haute-densité), dans les zones refuge d'olivier sauvage (oléastre) et sur olivier féral. Les facteurs pédoclimatiques qui caractérisent les sites d'échantillonnage ont également été pris en considération. L'analyse de la nématofaune a révélé d'une grande diversité spécifique, de nombreuses espèces étant décrites pour la première fois sur olivier, et une nouvelle espèce (Meloidogyne spartelensis) ayant été découverte. La diversité, la composition taxonomique, trophique et fonctionnelle, la dominance des taxons, les patrons de communautés sont fortement affectés par les différents forçages pris en compte. Le gradient d'anthropisation croissante (sauvage vs féral vs cultivé traditionnel vs cultivé haute-densité) est la variable qui impacte le plus la diversité par réduction de la richesse spécifique et l'augmentation de l'abondance en NPP. L'étude a également porté une attention particulière sur la diversité des nématodes à galles des racines du genre Meloidogyne, un des principaux ravageurs de l'olivier. Elle a indiqué la dispersion de M. javanica dans les vergers et sur olivier féral, alors que d'autres espèces (M. arenaria, M. hapla et M. spartelensis) sont confinées dans les zones refuge des oléastres. Afin d'analyser la diversité génétique, des marqueurs morphologiques et moléculaires ont dévoilé d'une diversité importante entre et au sein des différentes populations de Meloidogyne. Les études diligentées dans le cadre de cette thèse confirment que la diversité et la structure des communautés de NPP pourraient être des indicateurs pertinents pour évaluer la santé des sols dans les agro et écosystèmes, en corrélant diversité et pathogénicité des communautés. Elles soulignent donc l'importance de la diversité parasitaire comme variable prioritaire à prendre en compte pour inspirer des stratégies de gestion des parasites basées sur le concept de résilience de la diversité (même s'il s'agit de parasites), pour une gestion durable des communautés de NPP et la préservation des milieux. / Human activities increasingly frequent and persistent in ecosystems on one hand, and cropping system intensification on the other hand partly with radical methods to control pests and diseases of crops, raise questions about the ecological risks related to biotop changes, including disturbances of living organism communities. Plant-parasitic nematodes (PPN), microscopic round soil-borne worms that cause significant losses of crop production, are everywhere present in communities. They respond quickly to external forces (e.g. human and environmental) by changing the structure of their communities. In this thesis, we seek to better understand the effect of the factors involved in the assemblage of PPN species in communities associated with the Mediterranean olive tree and to determine the response of these communities to forces imposed by olive domestication, by crop intensification and by various environmental factors. The study was conducted in all olive-growing regions in Morocco (traditional low density and high density orchards), in refugia areas for wild olive (oleaster) and on feral olive trees. The soil and climatic factors that characterize the sampling sites were also considered. The analysis of the nematofauna revealed a wide species diversity, many species being described for the first time on olive tree, and a new species (Meloidogyne spartelensis) have been discovered. The diversity, the species / trophic / functional structure of the communities, the dominance of the taxa, and the community patterns are strongly affected by the various forces considered. The increasing anthropogenic gradient (wild vs feral vs traditional cultivation vs high-density cultivation) is the variable that mostly impacts the diversity by reducing the species richness and increasing the abundance of PPN. A particular attention was attributed in this study to the diversity of root-knot nematodes Meloidogyne, a major pest of the olive tree. It revealed that M. javanica is widespread in orchards and olive feral, while other species (M. arenaria, M. hapla and M. spartelensis) are confined in oleaster refuge areas. In order to analyse the genetic diversity, morphological and molecular markers have revealed a significant diversity between and within different Meloidogyne populations. These thesis studies confirm that both the diversity and the structure of the PPN communities could be relevant indicators to assess soil health in agro and ecosystems, by correlating diversity and pathogenicity of communities. They therefore emphasize the importance of parasite diversity as a main variable to consider for inspiring pest control strategies based on the concept of diversity resilience (even if it concerns parasites) for sustainable management of PPN communities and for environment preservation.
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Efeitos e formas de aplicação de Bacillus subtilis no controle de nematoides em cana-de-açúcar / Effects and application forms of Bacillus subtilis to control nematodes in sugarcane

Mazzuchelli, Rita de Cássia Lima 29 August 2013 (has links)
Made available in DSpace on 2016-01-26T18:56:29Z (GMT). No. of bitstreams: 1 Rita de Cassia Lima Mazzuchelli.pdf: 264845 bytes, checksum: d6d57b7dd9a9f9a69fc6599de070e810 (MD5) Previous issue date: 2013-08-29 / The aim of this study was to evaluate two methods of application of Bacillus subtilis in biological control of nematodes in two varieties of sugarcane by comparing with the conventional chemical control. The experiment was conducted in the municipality of Caiabu in an area with nematode infestation. Two genotypes of sugarcane which the action of nematodes were used in the experiment SP81-3250 and RB867515. The employee was a randomized complete block design with five replications. Treatments were two genotypes of sugarcane combined with four ways to control nematodes (carbofuran, B. subtilis applied at planting, B. subtilis applied in post -emergence control and without the application of chemical or biological nematicide) total of 40 plots. During the conduct of the culture three assessments for quantification of nematodes on the roots was carried out. Was also carried out an assessment of chlorophyll content, tillering and biomass energy potential by the calorimeter method at 180 days after planting. At harvest yield was determined and made technological analysis of sugarcane. Chemical and biological control with carbofuran with Bacillus subtilis were effective for controlling nematodes reviews. There were no differences in the efficiency of the control in the evaluation of two forms of application of bacteria in soil. There increments Brix and Pol in variety SP81-3250 when we applied the treatment with B. subtlis. / O objetivo do presente trabalho foi o de avaliar duas formas de aplicação de Bacillus subtilis no controle biológico de nematoides em duas variedades de cana-de-açúcar comparando-se com o controle químico convencional. O experimento foi desenvolvido no município de Caiabu, em uma área com histórico de infestação de nematoides. Foram utilizados no experimento dois genótipos de cana-de-açúcar susceptíveis a ação de nematoides, SP81-3250 e RB867515. O delineamento empregado foi de blocos casualizados, com cinco repetições. Os tratamentos foram dois genótipos de cana-de-açúcar combinados com quatro formas de controle de nematoides (carbofurano, B. subtilis aplicado no sulco de plantio, B. subtilis aplicado em pós-emergência e controle sem aplicação de nematicida químico ou biológico), totalizando 40 parcelas. Durante a condução da cultura foram realizadas três avaliações para quantificação de nematoides nas raízes. Foi também realizado uma avaliação de teor de clorofila, perfilhamento e potencial energético da biomassa pelo método do calorímetro aos 180 dias após o plantio. No momento da colheita foi determinada a produtividade e realizadas análises tecnológicas da cana-de-açúcar. O controle químico com carbofurano e biológico com Bacillus subtilis foram eficientes para controlar os nematoides avaliados. Não houve diferenças quanto à eficiência de controle na avaliação das duas formas de aplicação da bactéria no solo. Ocorreram incrementos do Brix e do Pol na variedade SP81-3250 quando aplicou-se o tratamento com B. subtlis.
69

Efeitos e formas de aplicação de Bacillus subtilis no controle de nematoides em cana-de-açúcar / Effects and application forms of Bacillus subtilis to control nematodes in sugarcane

Mazzuchelli, Rita de Cássia Lima 29 August 2013 (has links)
Made available in DSpace on 2016-07-18T17:51:12Z (GMT). No. of bitstreams: 1 Rita de Cassia Lima Mazzuchelli.pdf: 264845 bytes, checksum: d6d57b7dd9a9f9a69fc6599de070e810 (MD5) Previous issue date: 2013-08-29 / The aim of this study was to evaluate two methods of application of Bacillus subtilis in biological control of nematodes in two varieties of sugarcane by comparing with the conventional chemical control. The experiment was conducted in the municipality of Caiabu in an area with nematode infestation. Two genotypes of sugarcane which the action of nematodes were used in the experiment SP81-3250 and RB867515. The employee was a randomized complete block design with five replications. Treatments were two genotypes of sugarcane combined with four ways to control nematodes (carbofuran, B. subtilis applied at planting, B. subtilis applied in post -emergence control and without the application of chemical or biological nematicide) total of 40 plots. During the conduct of the culture three assessments for quantification of nematodes on the roots was carried out. Was also carried out an assessment of chlorophyll content, tillering and biomass energy potential by the calorimeter method at 180 days after planting. At harvest yield was determined and made technological analysis of sugarcane. Chemical and biological control with carbofuran with Bacillus subtilis were effective for controlling nematodes reviews. There were no differences in the efficiency of the control in the evaluation of two forms of application of bacteria in soil. There increments Brix and Pol in variety SP81-3250 when we applied the treatment with B. subtlis. / O objetivo do presente trabalho foi o de avaliar duas formas de aplicação de Bacillus subtilis no controle biológico de nematoides em duas variedades de cana-de-açúcar comparando-se com o controle químico convencional. O experimento foi desenvolvido no município de Caiabu, em uma área com histórico de infestação de nematoides. Foram utilizados no experimento dois genótipos de cana-de-açúcar susceptíveis a ação de nematoides, SP81-3250 e RB867515. O delineamento empregado foi de blocos casualizados, com cinco repetições. Os tratamentos foram dois genótipos de cana-de-açúcar combinados com quatro formas de controle de nematoides (carbofurano, B. subtilis aplicado no sulco de plantio, B. subtilis aplicado em pós-emergência e controle sem aplicação de nematicida químico ou biológico), totalizando 40 parcelas. Durante a condução da cultura foram realizadas três avaliações para quantificação de nematoides nas raízes. Foi também realizado uma avaliação de teor de clorofila, perfilhamento e potencial energético da biomassa pelo método do calorímetro aos 180 dias após o plantio. No momento da colheita foi determinada a produtividade e realizadas análises tecnológicas da cana-de-açúcar. O controle químico com carbofurano e biológico com Bacillus subtilis foram eficientes para controlar os nematoides avaliados. Não houve diferenças quanto à eficiência de controle na avaliação das duas formas de aplicação da bactéria no solo. Ocorreram incrementos do Brix e do Pol na variedade SP81-3250 quando aplicou-se o tratamento com B. subtlis.
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Mechanism of resistance to Meloidogyne Incognita and Meloidogyne Javanica in Cucumis Africanus and Cucumis myriocarpus seedlings

Ramatsitsi, Mukondeleni Ndivhuwo January 2017 (has links)
Thesis (M.Sc. (Horticulture)) -- University of Limpopo, 2017. / Root-knot (Meloidogyne species) nematodes are economically destructive pathogens of over 3000 species, whereas others have resistance to Meloidogyne species. Wild watermelon (Cucumis africanus) and wild cucumber (Cucumis myriocarpus) are highly resistant to Meloidogyne species, particularly M. incognita and M. javanica. The two Cucumis species are used in inter-generic grafting with watermelon (Citrullus lanatus) as nematode resistant rootstocks. Also, the two Cucumis species are used in traditional medicine and in plant-parasitic nematode management as phytonematicides. The form of nematode resistance, which is essential in plant breeding, is not documented for the two Cucumis species. The objective of this study was to determine the form of nematode resistance in the two Cucumis species to M. incognita and M. javanica under greenhouse conditions. Four parallel experiments were each conducted under greenhouse conditions. Uniform six-week old Cucumis seedlings were transplanted into 250 ml polystyrene cups filled with 200 ml growing medium of steam-pasteurised fine sand. A week after transplanting, Cucumis seedlings were each infested by dispensing approximately 100 M. incognita second-stage juveniles (J2) or M. javanica J2 using a 20 ml plastic syringe by placing into 5-cm-deep furrow around the seedling stem and covered with growing medium. Treatments (periodic harvest intervals) were arranged in a randomised complete block design, replicated five times. Five seedlings from each experiment were harvested every second day, for 30 days, with stained roots being assessed for necrotic spot (suberised cells) number, giant cell number, proliferation of rootlet interference number and root gall number. Periodic harvest intervals were highly significant (P ≤ 0.01) on necrotic spot number, proliferation of rootlet interference number and root gall number in C. africanus-M. incognita relations, but were not significant for giant cell number. Treatments contributed 59, 64 and 50% in total treatment variation (TTV) of necrotic spot number, proliferation of rootlet interference number and root gall number, respectively. Harvest period had highly significant effects on necrotic spot number, giant cell number, proliferation of rootlet interference number and root gall number in C. africanus-M. javanica relations. Treatments contributed 55, 71, 63 and 59% in TTV of necrotic spot number, giant cell number, proliferation of rootlet interference number and root gall number, respectively. Periodic harvest intervals were significant (P ≤ 0.05) on giant cell number and highly significant on root gall number in C. myriocarpus-M. incognita relations. However, there were no significant treatment differences on necrotic spot number and proliferation of rootlet interference number. Treatments contributed 57 and 57% in TTV of root gall number and giant cell number, respectively. Harvest period had highly significant effects on giant cell number, proliferation of rootlet interference number and root gall number, but were not significant on necrotic spot number in C. myriocarpus-M. javanica relations. Treatments accounted for 67, 49 and 53% in TTV of giant cell number, proliferation of rootlet interference number and root gall number, respectively. In conclusion, the mechanism of resistance to M. incognita and M. javanica in both C. africanus and C. myriocarpus was post-infectional nematode resistance, which has attributes for introgression into commercial nematode-susceptible Cucumis cultivars. / Agricultural Research Council (ARC), National Research Foundation of South Africa; and the ARC-Universities Collaboration Centre for Smallholder Farmers

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