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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

Interação fungos micorrízicos arbusculares e Meloidogyne incognita, em plantas de tomateiro e pimentão

Bordin, Silvia Santin [UNESP] 02 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-02Bitstream added on 2014-06-13T20:25:40Z : No. of bitstreams: 1 bordin_ss_dr_botfca.pdf: 204968 bytes, checksum: 320fe191efc3df447d669c7069b30d07 (MD5) / O tomateiro e o pimentão são importantes culturas no Brasil. Porém, como muitas culturas são atacadas pelos chamados nematóides causadores de galhas, entre estes a espécie Meloidogyne incognita Chitwood. Este nematóide representa grandes perdas em ambas culturas. Estas culturas também são colonizadas por fungos micorrízicos arbusculares, os quais podem trazer vários benefícios às plantas. Dentre esses benefícios temos o auxílio na absorção de fósforo e a redução na severidade de doenças. Este trabalho analisou a interação fungos MA e as raças 2 e 3 de M. incognita em plantas de tomateiro e pimentão. Observou-se que, em tomateiro, os fungos MA, aumentaram os teores de fósforo na parte aérea, sendo que Glomus clarum foi mais eficiente que Gigaspora margarita. Ambas as raças de M. incognita foram bastante agressivas às plantas de tomateiro, porém os fungos MA foram eficientes em auxiliar a planta a superar o dano do nematóide. G. clarum, G. margarita e Glomus etunicatum melhoraram o desenvolvimento de plantas de pimentão, aumentaram os teores de fósforo na parte aérea e auxiliaram as plantas a superar os danos provocados pelo nematóide. / Tomato and pepper plants are important cultures in Brazil. But as many cultures are attacked by named root-knot nematodes , among them the Meloidogyne incognita (Kofoid & White) Chitwood races. This nematode represents big losses in both cultures. Those cultures are colonized by VA-mycorrizal fungi and they can help the plants. From among these benefices we have an aid in phosphorus assimilation and a reduction in the hardness of diseases. This work has analyzed the interaction between AM fungi and the races two and three of M. incognita in tomato plants and pepper plants. We observed in tomato plants that AM fungi has increased the phosphorus content in the shoot so Glomus clarum was more efficient than Gigaspora margarita. Both races of M. incognita were too aggressive in tomato plants, but MA fungi were efficient for helping the plants to support the damages of nematodes. G. clarum, G. margarita and Glomus etunicatum got better the development of pepper plants. They increased the phosphorus assimilation in the shoot and helped the plants to support the damage by nematodes.
62

Controle genético da resistência a Meloidogyne incognita em Cucumis melo L

Candido, Willame dos Santos [UNESP] 12 July 2013 (has links) (PDF)
Made available in DSpace on 2015-04-09T12:28:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-07-12Bitstream added on 2015-04-09T12:47:59Z : No. of bitstreams: 1 000819184.pdf: 195601 bytes, checksum: 56567545115d1021be4550fb5b30f4c9 (MD5) / Este estudo foi desenvolvido na Faculdade de Ciências Agrárias e Veterinárias (UNESP-FCAV), Câmpus de Jaboticabal- SP, com o objetivo de avaliar o modo de herança da resistência do melão ‘Gaúcho Redondo’ a Meloidogyne incognita. Para tanto, foi conduzido um experimento em delineamento em blocos casualizados, com três blocos e seis tratamentos, os quais envolveram as linhas parentais ‘Gaúcho Redondo’ (P1 resistente à M. incognita) e JAB 20 (P2 suscetível, resultado do programa de Melhoramento Genético da Cultura do Melão Rendilhado da UNESP-FCAV), assim como as gerações F1 (P1xP2), F2 (F1xF1), e retrocruzamentos (RC1P1 e RC1P2). Foram avaliadas plantas individuais após 70 dias da inoculação com o patógeno, por meio do fator de reprodução do nematoide (FR), calculado pela contagem do número de ovos e juvenis de segundo estádio, contido na suspensão de cada raiz processada, dividido pela população inicial. A hipótese de herança monogênica foi rejeitada ao nível de significância de 1% de probabilidade no teste do qui-quadrado (χ2), indicando que a resistência está sob controle de mais de um lócus gênico, o que foi confirmado pela análise quantitativa, que evidenciou a existência de seis genes envolvidos na herança da resistência ao nematoide. Houve predominância dos efeitos aditivos no controle da característica em estudo, o que permite resposta aos processos de seleção / This study was conducted at the College of Agriculture and Veterinary Sciences (UNESP-FCAV) in Jaboticabal-SP, in order to evaluate the mode of inheritance of resistance of melon 'Gaucho Round' to Meloidogyne incognita. Therefore, an experiment was conducted in randomized block design with three blocks and six treatments, which involved the parental lines 'Gaucho Round' (P1 resistant to M. incognita) and JAB 20 (P2 susceptible result of Breeding Program Culture Melon Tracery UNESP-FCAV), as well as the F1 (P1xP2), F2 (F1xF1) and backcross (RC1P1 and RC1P2). Individual plants were evaluated 70 days after inoculation with the pathogen through the nematode reproduction factor (FR), calculated by counting the number of eggs and second stage juveniles contained in the suspension of each root processed, divided by the initial population . The hypothesis of monogenic inheritance was rejected at a significance level of 1% probability in the chi-square (χ2), indicating that resistance is under the control of more than one gene locus, which was confirmed by quantitative analysis, which showed the existence of six genes involved in inheritance of resistance to nematodes. Predominance of additive effects in controlling the trait under study, allowing response to selection processes
63

Hospedabilidade de plantas daninhas a Meloidogyne spp. e interação entre herbicidas e nematicidas para a cultura de cana-de-açúcar / Hospitability of weeds to Meloidogyne spp. and interaction between herbicides and nematicides for the cane sugar culture

Giraldeli, Ana Ligia 11 December 2015 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2016-10-17T13:10:34Z No. of bitstreams: 1 DissALG.pdf: 1204557 bytes, checksum: 4002ead709914a04a88c0451755956b6 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-17T17:26:28Z (GMT) No. of bitstreams: 1 DissALG.pdf: 1204557 bytes, checksum: 4002ead709914a04a88c0451755956b6 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-17T17:26:58Z (GMT) No. of bitstreams: 1 DissALG.pdf: 1204557 bytes, checksum: 4002ead709914a04a88c0451755956b6 (MD5) / Made available in DSpace on 2016-10-17T17:35:13Z (GMT). No. of bitstreams: 1 DissALG.pdf: 1204557 bytes, checksum: 4002ead709914a04a88c0451755956b6 (MD5) Previous issue date: 2015-12-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The sugarcane has great economic importance in Brazil. To keep productivity several biotic and abiotic factors can positively or negatively influence. Among them, weeds, nematodes and synergistic action between pesticides to control both can be cited. Thus, the present work aimed at studying possible common weeds in the mechanized harvesting system that can serve as hosts for the root knot nematode: Meloidogyne incognita and / or M. javanica and study the interaction between herbicides and nematicides used in the groove planting of sugarcane. Two experiments were carried in a greenhouse at the Agricultural Sciences Center (CCA-UFSCar), Araras, SP. The first experiment evaluated the host status ten weeds, as follows: Ipomoea triloba (Dammer), Merremia aegyptia (L.) Urban, Luffa aegyptiaca Mill, Euphorbia heterophylla L., Ricinus communis L., Crotalaria spectabilis Roth, Mucuna aterrima ( Piper & Tracy) Holland, Chloris polydactyla (L.) Sw., Digitaria horizontalis Willd., Urochloa decumbens (Stapf) RD Webster and the control (tomato Santa Cruz Kada) when inoculated with M. incognita or M. javanica in a completely randomized design in a factorial 11 x 2, with six repetitions. The plants were inoculated with 2.000 eggs and J2, and there were three plants per plot (6.000 eggs and J2 per pot - repetition). Sixty days after inoculation (DAI) the plants were removed and evaluated according to the reproduction factor (FR), final nematodes population (PF) and reproduction index (IR). In the second experiment the effect of interaction between two nematicides applied in contact with the stalks was evaluated. The nematicides tested were: benfuracarb (5,0 L ha-1) and carbofuran (50 Kg ha-1), and the herbicides applied preemergence of culture were: sulfentrazone (1,6 L p.c. ha-1), diuron + hexazinone (2,5 Kg ha1), saflufenacil (0,14 Kg p.c. ha-1) and amicarbazone (1,5 Kg p.c. ha-1). The experiment was carried in a completely randomized design in a factorial 15 x 5, with four replications in three sugarcane varieties (RB867515, RB975952 and RB975201). The first factor was corresponded to the 15 treatments and the second, to the five evaluation periods. Evaluations of intoxication symptoms were performed at 7, 15, 30, 45 and 60 days after emergence (DAE) of culture. In the last assessment biometric parameters height (cm), leaf area (cm²) and dry biomass of the aerial part (g) were evaluated. Regarding to the host status of weeds, it was found that L. aegyptiaca behaved as host of both nematodes, with FR > 1, higher than the control. The D. horizontalis was classified as host of M. incognita and non-host of M. javanica. C. spectabilis had the lowest FR and PF. R. communis and I. triloba present galls when inoculated with M. incognita, but were not considered host for presenting FR < 1. None of the weeds tested was considered immune, that is, with RF = 0. Regarding the interaction of herbicides and nematicides in all treatments, plants recover 60 DAE, and in treatments with the use of sulfentrazone increase in symptoms of poisoning was observed. As for the biometric parameters evaluated at 60 DAE, there was no statistical difference only in the variety RB867515 for height. In this case, the treatments amicarbazone / benfuracarb and amicarbazone / carbofuran plants were higher than the control and other interactions. / A cana-de-açúcar tem grande importância econômica no Brasil. Para manter sua produtividade diversos fatores bióticos e abióticos podem influenciar positiva ou negativamente. Dentre eles, podem ser citados as plantas daninhas, os nematóides e a interação entre produtos fitossanitários para o controle de ambos. Em função disto, o presente trabalho teve como objetivo estudar possíveis plantas daninhas comuns no sistema colheita mecanizada que possam servir de hospedeiras para os nematóides-das-galhas: Meloidogyne incognita (raça 3) e/ou M. javanica e estudar a interação entre herbicidas e nematicidas usados no plantio da cana-de-açúcar. Foram desenvolvidos dois experimentos em casa-de-vegetação do Centro de Ciências Agrárias (CCA-UFSCar), em Araras, SP. O primeiro experimento avaliou a hospedabilidade de dez plantas daninhas a nematóides, sendo elas: Ipomoea triloba (L.), Merremia aegyptia (L.) Urban, Luffa aegyptiaca Mill., Euphorbia heterophylla L., Ricinus communis L., Crotalaria spectabilis Roth, Mucuna aterrima (Piper & Tracy) Holland, Chloris polydactyla (L.) Sw., Digitaria horizontalis Willd., Urochloa decumbens (Stapf) R. D. Webste e a testemunha (tomateiro Santa Cruz Kada) quando inoculadas com M. incognita (raça 3) ou M. javanica, em delineamento inteiramente casualizado, em esquema fatorial 11 x 2, com seis repetições. As plantas foram inoculadas com 2.000 ovos e juvenis de segundo estádio (J2), sendo que havia três plantas por unidade experimental (6.000 ovos e J2 por vaso – repetição) e 60 dias após a inoculação (DAI) as plantas foram retiradas e avaliadas segundo o fator de reprodução (FR), população final de nematóides (PF) e índice de reprodutividade (IR). No segundo experimento foi avaliado o efeito da interação entre dois nematicidas aplicados em contato com os toletes, sendo eles: benfuracarbe (5,0 L ha-1) e carbofuran (50 Kg ha-1), com os herbicidas aplicados em pré-emergência da cultura: sulfentrazone (1,6 L p.c. ha-1), diuron + hexazinone (2,5 Kg ha-1), saflufenacil (0,14 Kg p.c. ha-1) e amicarbazone (1,5 Kg p.c. ha-1). O experimento foi conduzido em delineamento inteiramente casualizado, com quatro repetições, em três variedades de cana-de-açúcar (RB867515, RB975201 e RB975952). As avaliações de sintomas de intoxicação foram realizadas aos 7, 15, 30, 45 e 60 dias após a emergência (DAE) da cultura. Na última avaliação foram determinados os parâmetros biométricos altura (cm), área foliar (cm²) e biomassa seca da parte aérea (g). Com relação à hospedabilidade das plantas daninhas, foi verificado que L. aegyptiaca comportou-se como hospedeira de ambos os nematóides, com FR > 1, sendo superior a testemunha. A D. horizontalis foi classificada como hospedeira de M. incognita (raça 3) e não-hospedeira de M. javanica. A C. spectabilis apresentou os menores FR e PF. A R. communis e I. triloba apresentaram galhas quando inoculadas com M. incognita (raça 3), mas não foram consideradas hospedeiras por apresentarem FR < 1. Nenhuma das plantas daninhas foi considerada imune, ou seja, com FR = 0. Com relação a interação dos herbicidas e nematicidas, em todos os tratamentos as plantas se recuperaram aos 60 DAE, sendo que nos tratamentos com o uso do herbicida sulfentrazone foi observado os mais elevados sintomas de intoxicação. Quanto aos parâmetros biométricos avaliados aos 60 DAE, houve diferença estatística apenas na variedade RB867515 quanto à altura, nesse caso os tratamentos amicarbazone / benfuracarbe e amicarbazone / carbofuran foram superiores à testemunha e demais interações.
64

Reação de genótipos de Capsicum annuum a nematoides de galha / Reaction of Capsicum annuum genotypes to root-knot nematodes

Soares, Renato Silva [UNESP] 21 February 2017 (has links)
Submitted by RENATO SILVA SOARES null (renato_2366@hotmail.com) on 2017-04-16T22:48:52Z No. of bitstreams: 1 Dissertação Renato Final.pdf: 1678992 bytes, checksum: 1f1da592f1239dc378237df3f8910585 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-18T17:49:50Z (GMT) No. of bitstreams: 1 soares_rs_me_jabo.pdf: 1678992 bytes, checksum: 1f1da592f1239dc378237df3f8910585 (MD5) / Made available in DSpace on 2017-04-18T17:49:50Z (GMT). No. of bitstreams: 1 soares_rs_me_jabo.pdf: 1678992 bytes, checksum: 1f1da592f1239dc378237df3f8910585 (MD5) Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O pimentão (Capsicum annuum L.) apresenta grande importância socioeconômica, estando entre as dez hortaliças mais consumidas no Brasil. O cultivo dessa olerácea em ambiente protegido tem aumentado de forma significativa no decorrer dos anos. Entretanto, o cultivo intensivo nesse sistema tem causado aumento da incidência de nematoides de galha (Meloidogyne spp.). Uma forma de manejar esses fitoparasitas na cultura é o uso de cultivares ou porta-enxertos com resistência às principais espécies. O presente trabalho teve por objetivo avaliar a reação de genótipos de C. annuum quanto à resistência múltipla à Meloidogyne incognita raça 3, Meloidogyne javanica e Meloidogyne enterolobii. Por motivo de logística, o trabalho foi realizado em três experimentos, utilizando o delineamento inteiramente casualizado, sendo o primeiro em esquema fatorial 31 x 3 (27 genótipos de C. annuum, as cultivares de pimenta BRS Moema e BRS Mari, uma linhagem de C. frutescens e o tomateiro ‘Santa Cruz Kada’) e três espécies de nematoides (M. incognita raça 3, M. javanica e M. enterolobii), o segundo em esquema fatorial 39 x 3 (36 acessos de C. annuum, duas cultivares de pimenta utilizadas no primeiro experimento e o tomateiro ‘Santa Cruz Kada’) e as três espécies de nematoides mencionadas anteriormente, e o terceiro experimento em fatorial 27 x 3, sendo 24 genótipos de C. annuum, as cultivares de pimenta BRS Moema e de pimentão Ikeda, o tomateiro ‘Santa Cruz Kada’ e as três espécies de nematoides de galhas utilizadas nos experimentos 1 e 2. No ato do transplantio, as mudas foram inoculadas com 5.000 ovos e juvenis de segundo estádio de cada espécie de nematoide, separadamente. Considerou-se uma planta por vaso como uma repetição. A avaliação dos genótipos, em ambos os experimentos, ocorreu aos 90 dias após a inoculação. Avaliaram-se o número total de ovos e juvenis de segundo estádio (NTOJ), o número de ovos e juvenis de segundo estádio por grama de raiz (NOJGR), o índice de reprodução (IR) e o fator de reprodução (FR). Os dados foram submetidos à análise de variância, e quando identificadas diferenças significativas pelo teste F, foram agrupadas pelo teste de Scott-Knott, a 5% de probabilidade. Os genótipos de C. annuum CNPH 146, CNPH 185, CNPH 187, CNPH 698, CNPH 671, CNPH 672, CNPH 680, CNPH 717 e CNPH 718 foram classificados como resistentes e muito resistentes pelo fator de reprodução e índice de reprodução, respectivamente, a M. incognita raça 3 e M. javanica; no entanto, estes e os demais genótipos foram suscetíveis a M. enterolobii, pelo FR. Os acessos CNPH 47, CNPH 640, CNPH 677, CNPH 684, CNPH 690 e CNPH 693 foram classificados como ligeiramente resistentes a M. enterolobii, pelo IR. Utilizando o fator de reprodução como metodologia de seleção, não houve genótipos de C. annuum com resistência múltipla a M. incognita raça 3, M. javanica e M. enterolobii. / The sweet pepper (Capsicum annuum L.) presents great socioeconomic importance, being among the ten vegetables most consumed in Brazil. The cultivation of this crop in protected environment has increased significantly over the years. However, the intensive cultivation in this system has caused an increase in the incidence of root-knot nematodes (Meloidogyne spp.). One way to manage these phytoparasites in the crop is the use of cultivars or rootstocks with resistance to the main species. The objective of the present work was to evaluate the reaction of Capsicum annuum genotypes for multiple resistance to Meloidogyne incognita race 3, Meloidogyne javanica and Meloidogyne enterolobii. For reasons of logistics, the work was carried out in three experiments using a completely randomized design; the first one in a factorial scheme 31 x 3 (27 genotypes of C. annuum, the cultivars of pepper BRS Moema and BRS Mari, a line of C. frutescens and the tomato ‘Santa Cruz Kada’) and three nematode species (M. incognita race 3, M. javanica and M. enterolobii); the second in a 39 x 3 factorial scheme (36 accessions of C. annuum, the two pepper cultivars used in the first experiment and the tomato ‘Santa Cruz Kada’) and the three nematode species mentioned above; and the third experiment in factorial 27 x 3, being 24 genotypes of C. annuum, the cultivars of pepper BRS Moema and of sweet pepper Ikeda, the tomato 'Santa Cruz Kada' and the three species of nematodes used in experiments 1 and 2. After the transplanting, the seedlings were inoculated with 5000 eggs and second-stage juveniles of each nematode species separately. One plant per pot was considered as a repetition. The evaluation of genotypes in both experiments occurred at 90 days after inoculation. The total number of eggs and second-stage juveniles (NTOJ), number of eggs and second-stage juveniles per gram of root (NOJGR), reproduction index (IR) and reproduction factor (RF) were evaluated. Data were submitted to analysis of variance, and when significant differences were identified by the F test, were grouped by the Scott-Knott test at 5% probability. The genotypes of C. annuum CNPH 146, CNPH 185, CNPH 187, CNPH 698, CNPH 671, CNPH 672, CNPH 680, CNPH 717 and CNPH 718 were classified as resistant and very resistant by the reproduction factor and reproduction index, respectively, to M. incognita race 3 and M. javanica, however, these and the other genotypes were susceptible to M. enterolobii, by RF. The accessions CNPH 47, CNPH 640, CNPH 677, CNPH 684, CNPH 690 and CNPH 693 were classified as slightly resistant to M. enterolobii by IR. Using the reproduction factor as a selection methodology, there were no C. annuum genotypes with multiple resistance to M. incognita race 3, M. javanica and M. enterolobii.
65

Interação fungos micorrízicos arbusculares e Meloidogyne incognita, em plantas de tomateiro e pimentão /

Bordin, Silvia Santin, 1964- January 2002 (has links)
Orientador: Marli Teixeira Almeida Minhoni / Resumo: O tomateiro e o pimentão são importantes culturas no Brasil. Porém, como muitas culturas são atacadas pelos chamados nematóides causadores de galhas, entre estes a espécie Meloidogyne incognita Chitwood. Este nematóide representa grandes perdas em ambas culturas. Estas culturas também são colonizadas por fungos micorrízicos arbusculares, os quais podem trazer vários benefícios às plantas. Dentre esses benefícios temos o auxílio na absorção de fósforo e a redução na severidade de doenças. Este trabalho analisou a interação fungos MA e as raças 2 e 3 de M. incognita em plantas de tomateiro e pimentão. Observou-se que, em tomateiro, os fungos MA, aumentaram os teores de fósforo na parte aérea, sendo que Glomus clarum foi mais eficiente que Gigaspora margarita. Ambas as raças de M. incognita foram bastante agressivas às plantas de tomateiro, porém os fungos MA foram eficientes em auxiliar a planta a superar o dano do nematóide. G. clarum, G. margarita e Glomus etunicatum melhoraram o desenvolvimento de plantas de pimentão, aumentaram os teores de fósforo na parte aérea e auxiliaram as plantas a superar os danos provocados pelo nematóide. / Abstract: Tomato and pepper plants are important cultures in Brazil. But as many cultures are attacked by named root-knot nematodes , among them the Meloidogyne incognita (Kofoid & White) Chitwood races. This nematode represents big losses in both cultures. Those cultures are colonized by VA-mycorrizal fungi and they can help the plants. From among these benefices we have an aid in phosphorus assimilation and a reduction in the hardness of diseases. This work has analyzed the interaction between AM fungi and the races two and three of M. incognita in tomato plants and pepper plants. We observed in tomato plants that AM fungi has increased the phosphorus content in the shoot so Glomus clarum was more efficient than Gigaspora margarita. Both races of M. incognita were too aggressive in tomato plants, but MA fungi were efficient for helping the plants to support the damages of nematodes. G. clarum, G. margarita and Glomus etunicatum got better the development of pepper plants. They increased the phosphorus assimilation in the shoot and helped the plants to support the damage by nematodes. / Doutor
66

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.
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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.
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Reação de hospedeiro de espécies de eucalipto a Pratylenchus brachyurus e Meloidogyne incognita / Host-status of eucalyptus species to Pratylenchus brachyurus and Meloidogyne incognita

Victor Hugo Moura de Souza 16 January 2015 (has links)
O gênero Eucalyptus possui diversas espécies que apresentam grande valor comercial, sendo utilizado principalmente para produção de energia (carvão e lenha) e celulose-papel. Na literatura, entretanto, existem poucas informações acerca de nematoses nessa cultura. Além dessa carência e de sua importância econômica, o eucalipto é comumente cultivado em locais de alta incidência de Pratylenchus brachyurus e Meloidogyne incognita, além de ser consorciado com diversas outras culturas intolerantes, como por exemplo a soja. Dessa forma há uma necessidade de conhecer a reação das espécies de eucalipto a estes nematoides. Dito isso, o presente trabalho teve por objetivo testar a reação de algumas espécies de eucalipto a P. brachyurus e M.incognita. Foram realizados 6 experimentos, 5 envolvendo o nematoide das lesões e 1 com o nematoide de galhas. Os tratamentos foram inoculados com uma população inicial de nematoides e, após 90 dias, estimava-se o fator de reprodução (FR) e nematoides por grama de raiz (Nem/g). Adotou-se o critério baseado em Oostenbrink (1966), onde a espécie foi considerada suscetível quando apresenta FR >= 1 e resistente quando FR < 1. Dos eucaliptos testados, 6 apresentaram reação suscetível e 4 reação resistente para P. brachyurus. As espécies com maiores FR estão entre as mais utilizadas no Brasil, exceto E. saligna. Ressalta-se que estas não necessariamente são resistentes, necessitando apenas de um período maior para o estabelecimento do patógeno. Observou-se indícios de que E. saligna e E. camaldulensis sejam intolerantes a P.brachyurus. Para M. incognita raça 3 todas as espécies testadas foram resistentes. Aconselha-se a realização de experimentos com períodos superiores a 100 dias para uma correta classificação da reação de hospedeiro. O eucalipto é uma opção para aproveitamento de áreas infestadas com M. incognita raça 3, porém seu uso mostra-se um risco em áreas infestadas com P. brachyurus. / The Eucalyptus has several species with high commercial value and is used mainly for energy purpose (Charcoal and firewood) and paper. In the literature, however, there is little information about plant parasitic nematodes in this woody specie. In addition to this lack and its economic importance, eucalypts is also commonly cultivated in areas with high incidence of Pratylenchus brachyurus and Meloidogyne incognita, and consorted with several intolerant crops, such as soybean. Thus, there is a need to know the host status of the eucalypts species to these nematodes. With that, this work aimed to test the reaction of some Eucalyptus species to P.brachyurus and M. incognita. For this purpose six experiments were performed, five to test the lesion nematode and one to test the root-knot nematode. The treatments were inoculated and, after 90 days, it was estimated the reproduction factor (FR) and nematodes per gram of root (Nem/g). The present work adopted the criteria based on Oostenbrink (1966), where the species was considered susceptible when presenting FR >= 1 and resistant when FR < 1. Of species tested, six were susceptible hosts and four resistant host to P. brachyurus. The species with highest FR are among the most used eucalypts in Brazil, except E. saligna. It is emphasized that those species with FR < 1 are not necessarily resistant, requiring only a longer period for the pathogen establishment. There was some evidence that E. saligna and E. camaldulensis are intolerant hosts to P. brachyurus. To M. incognita Race 3 all tested species were resistant. It is advisable to perform experiments for periods longer than 100 days to a correct classification of host status. Eucalyptus is an option for utilization of areas infested with M. incognita race 3, but its use appears to be a risk in Pratylenchus brachyurus infested areas.
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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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The interaction between root knot nematodes (Meloidogyne spp.) and soft rot Enterobacteriaceae (Pectobacterium spp.) and their host Solanum tuberosum

Mongae, Aobakwe Oratile January 2013 (has links)
Meloiodgyne incognita, one of the most aggressive plant parasitic nematodes species on potato in South Africa, belongs to a group of plant parasitic nematodes commonly known as root knot nematodes (RKN). This group of nematodes is widely distributed throughout the world. Meloidogyne spp. cause major economic losses to important crops such as potato and therefore decrease their market value in many countries across the world. The second stage juveniles are the only mobile and infective phase of the root knot nematode. As they infect host roots, they create wounds that can be used by other plant pathogens to penetrate the host in large numbers. The most effective management strategy for root knot nematodes is the use of nematicides such as Temik and Methyl bromide. However, these have been banned due to adverse on the environment. Therefore, Meloidogyne spp. will inevitably become a big problem in the potato industry of many countries due to the lack of effective alternatives to banned chemicals. Pectobacterium carotovorum subsp. brasiliensis (Pcb) is one of the most important soft rot-causing agents in South Africa. This pathogen belongs to a group of pathogens commonly known as soft rot Enterobacteriaceae (SRE). Bacteria belonging to this group of pathogens are known to cause soft rot and blackleg diseases on potato and other crops. Pcb is known as an opportunistic pathogen that can only penetrate host root tissue through natural openings or wounds that result from a variety of agents. Post penetration, the bacteria will increase in number and cause soft rot and blackleg. As rotting plant tissue disintegrates the bacteria escapes into the soil where it serves as inoculum and can infect healthy hosts. Many interactions have been documented between Meloidogyne spp. and other plant pathogens but to our knowledge there are no interactions that have been reported between Meloidogyne spp. and Pectobacterium spp. Considering the life cycles of RKN and SRE, we hypothesised that there could be an interaction between the two pathogen groups. Since both RKN and SRE are potato pathogens, they share the same space in the rhizosphere. This likely can lead to synergies and complex formation between the two pathogens. Likely, the wounds created by RKN J2s as they penetrate plant tissue can potentially be used by opportunistic Pcb to infect various hosts. It is from these identified overlaps that the first part of this study focused on investigating the potential interaction between M. incognita and Pcb. The first objective was to determine whether Pcb can attach onto M. incognita J2s and, if this was the case, to determine whether the J2s can disseminate the bacteria as they move around in the environment. The second objective was to determine whether there is a synergistic interaction between RKN and SRE and the combined effect of the two pathogens on their host Solanum tuberosum cv Mondial. The results obtained in the first part of the study strongly suggested that Pcb can attach onto M. incognita J2s and can be disseminated as the J2s move around in the environment. Thus, this indicated that there is a synergistic interaction between M. incognita and Pcb as there was increased disease severity and incidence in plants inoculated with both pathogens compared to those inoculated with individual pathogens. Significantly higher Pcb concentrations were found in plants inoculated with both pathogens. There was no breakage of tolerance to Pcb-caused blackleg on an otherwise resistant cultivar, BP1. The second aim of this study was to determine whether the induction of natural resistance using environmentally friendly resistance inducing chemicals can potentially be used as an alternative to chemical control. To this end, the effect of three inducers at different concentrations, amongst DL-β-aminobutyric acid, Acibenzolar-s-methyl and Messenger on potato plants infected with RKN was compared. The most effective resistance inducer amongst the three was 20mM BABA as it was able to reduce the number of J2s that penetrated host tissue, the number of females in the roots and the rate of egg production. Furthermore, the galling index observed in potato roots was significantly lower when plants were treated with 20mM BABA. Additionally, the reduced rate of RKN infection in plants primed with 20mM led to a decrease in the rate of Pcb infection. / Dissertation (MSc)--University of Pretoria, 2013. / gm2013 / Microbiology and Plant Pathology / Unrestricted

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