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Registro Completo |
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Biblioteca(s): |
Embrapa Mandioca e Fruticultura. |
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Data corrente: |
16/04/2004 |
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Data da última atualização: |
16/04/2004 |
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Autoria: |
FAUQUET, C. M.; FONDONG, V.; PITA, J.; TORES-JEREZ, I.; OTIM-NAPE, W. G.; OGWAL, S.; SANGARE, A.; REY, C.; BROWN, J. K.; BEACHY, R. N. |
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Título: |
Etiology of the cassava mosaic disease in Africa reveals increasing complexity and diversity. |
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Ano de publicação: |
1998 |
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Fonte/Imprenta: |
Revista Brasileira de Mandioca, Salvador, v. 17, p. 39, nov., 1998., Suplemento. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: Since the beginning of this century cassava mosaic disease has been reported in all the African countries growing cassava. Symptoms vary somewhat from one country to the nex but always show mosaic, leaf curl and a significant reduction in yield. The presence of a dramatic new virus epidemic in cassava has caused increasing concern in Uganda since 1986. The new disease induces very severe symptoms, often resulting in total yield loss and failure of cutting establishment from infected stems. Two virus species have been isolated both from these plants and the whitefly vectors; the African cassava mosaic virus (ACMV) and the East African cassava mosaic virus (EACMV). Infection with the former is correlated with mild symptoms whilst presence of the latter causes severe symptoms in the crop. Sequence comparison of the EACMV virus isolate with other cassava viruses revealed that it is a recombinant between EACMV and ACMV. A large sampling of infected cassava plants from Uganda, allowed us to identify mild and severe strains of both irrespective of the symptoms induced on cassava, thereby indicating the absence of correlation between recombination and symptom severety. Comparison of mitochondria DNA sequences from whiteflies collected in each ecological situation indicated that a distinct population of B. tabaci, presently of unknown origin, is correlated with the presence of the severe symptoms and therefore with EACMV/UG. In west Africa the variety of symptoms seen on cassava are difficult to the cassava genotype or to the virus isolate. The two virus species; ACMV and EACMV, have also been isolated in Camerron and in Ivory Coast. A range of symptoms have been recorded in cassava and can now be reproduced on artificial hosts from crude sap and from infectious clones. Studies have revealed that, while ACMV is very similar throughout Africa, EACMV reveals the presence of different recombined fragments of unknown origin. The importance and relevance of these findings relative to symptoms on cassava and the epidemic in Uganda will be discussed. MenosAbstract: Since the beginning of this century cassava mosaic disease has been reported in all the African countries growing cassava. Symptoms vary somewhat from one country to the nex but always show mosaic, leaf curl and a significant reduction in yield. The presence of a dramatic new virus epidemic in cassava has caused increasing concern in Uganda since 1986. The new disease induces very severe symptoms, often resulting in total yield loss and failure of cutting establishment from infected stems. Two virus species have been isolated both from these plants and the whitefly vectors; the African cassava mosaic virus (ACMV) and the East African cassava mosaic virus (EACMV). Infection with the former is correlated with mild symptoms whilst presence of the latter causes severe symptoms in the crop. Sequence comparison of the EACMV virus isolate with other cassava viruses revealed that it is a recombinant between EACMV and ACMV. A large sampling of infected cassava plants from Uganda, allowed us to identify mild and severe strains of both irrespective of the symptoms induced on cassava, thereby indicating the absence of correlation between recombination and symptom severety. Comparison of mitochondria DNA sequences from whiteflies collected in each ecological situation indicated that a distinct population of B. tabaci, presently of unknown origin, is correlated with the presence of the severe symptoms and therefore with EACMV/UG. In west Africa the variety of symptoms seen on c... Mostrar Tudo |
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Categoria do assunto: |
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Marc: |
LEADER 02734naa a2200229 a 4500
001 1651728
005 2004-04-16
008 1998 bl uuuu u00u1 u #d
100 1 $aFAUQUET, C. M.
245 $aEtiology of the cassava mosaic disease in Africa reveals increasing complexity and diversity.
260 $c1998
520 $aAbstract: Since the beginning of this century cassava mosaic disease has been reported in all the African countries growing cassava. Symptoms vary somewhat from one country to the nex but always show mosaic, leaf curl and a significant reduction in yield. The presence of a dramatic new virus epidemic in cassava has caused increasing concern in Uganda since 1986. The new disease induces very severe symptoms, often resulting in total yield loss and failure of cutting establishment from infected stems. Two virus species have been isolated both from these plants and the whitefly vectors; the African cassava mosaic virus (ACMV) and the East African cassava mosaic virus (EACMV). Infection with the former is correlated with mild symptoms whilst presence of the latter causes severe symptoms in the crop. Sequence comparison of the EACMV virus isolate with other cassava viruses revealed that it is a recombinant between EACMV and ACMV. A large sampling of infected cassava plants from Uganda, allowed us to identify mild and severe strains of both irrespective of the symptoms induced on cassava, thereby indicating the absence of correlation between recombination and symptom severety. Comparison of mitochondria DNA sequences from whiteflies collected in each ecological situation indicated that a distinct population of B. tabaci, presently of unknown origin, is correlated with the presence of the severe symptoms and therefore with EACMV/UG. In west Africa the variety of symptoms seen on cassava are difficult to the cassava genotype or to the virus isolate. The two virus species; ACMV and EACMV, have also been isolated in Camerron and in Ivory Coast. A range of symptoms have been recorded in cassava and can now be reproduced on artificial hosts from crude sap and from infectious clones. Studies have revealed that, while ACMV is very similar throughout Africa, EACMV reveals the presence of different recombined fragments of unknown origin. The importance and relevance of these findings relative to symptoms on cassava and the epidemic in Uganda will be discussed.
700 1 $aFONDONG, V.
700 1 $aPITA, J.
700 1 $aTORES-JEREZ, I.
700 1 $aOTIM-NAPE, W. G.
700 1 $aOGWAL, S.
700 1 $aSANGARE, A.
700 1 $aREY, C.
700 1 $aBROWN, J. K.
700 1 $aBEACHY, R. N.
773 $tRevista Brasileira de Mandioca, Salvador$gv. 17, p. 39, nov., 1998., Suplemento.
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Registro original: |
Embrapa Mandioca e Fruticultura (CNPMF) |
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Biblioteca(s): |
Embrapa Cerrados. |
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Data corrente: |
06/08/2012 |
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Data da última atualização: |
06/08/2012 |
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Tipo da produção científica: |
Artigo em Anais de Congresso |
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Autoria: |
MENDANHA, K. S.; MAGNABOSCO, C. de U.; LOPES, F. B.; NAKAGWA, A. F.; CASTRO, L. M. de; FERREIRA, L. G. B. |
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Afiliação: |
KARINE SILVA MENDANHA, UFG; CLAUDIO DE ULHOA MAGNABOSCO, CPAC; FERNANDO BRITO LOPES, BOLSISTA CAPES; ÂNGELO FUMIO NAKAGWA, GUAPORÉ AGROPECUÁRIA; LETÍCIA MENDES DE CASTRO, UFG; LARA GABRIELA BRITO FERREIRA, UFG. |
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Título: |
Tendência genética de características relacionadas à velocidade de crescimento de bovinos Nelore Mocho. |
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Ano de publicação: |
2012 |
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Fonte/Imprenta: |
In: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 49., 2012, Brasília. A produção animal no mundo em transformação: anais. Brasília, DF: SBZ, 2012. 1 CD-ROM. |
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Idioma: |
Português |
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Conteúdo: |
Pesquisas efetivas que avaliam a eficiência produtiva de bovino da raça Nelore, variedade mocho, são incipientes. Por isto, este estudo foi realizado com o objetivo de estimar tendências genéticas para as características de dias para se ganhar 160 kg (D160) na fase pré-desmama, e dias para se ganhar 240 kg (D240) na fase pós-desmama, em bovinos da raça Nelore, variedade mocho, criados na região de Mato Grosso. Os componentes de (co)variância e parâmetros genéticos foram estimados por meio do software MTDFREML. As predições médias para tendência genética de D160 e D240 foram -3,29 e -4,48, respectivamente. As estimativas de tendências genéticas evidenciaram a existência de variabilidade suficiente para promover melhoria do rebanho em estudo. Embora estas características não sejam adotadas como critérios de seleção, sua utilização proporcionaria melhoria do rebanho, por meio da seleção de animais mais precoces e com maior velocidade de crescimento. |
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Palavras-Chave: |
Nelore. |
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Thesaurus NAL: |
zebu. |
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Categoria do assunto: |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/63004/1/CD411Magnabosco14.pdf
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Marc: |
LEADER 01687nam a2200193 a 4500
001 1930482
005 2012-08-06
008 2012 bl uuuu u00u1 u #d
100 1 $aMENDANHA, K. S.
245 $aTendência genética de características relacionadas à velocidade de crescimento de bovinos Nelore Mocho.
260 $aIn: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 49., 2012, Brasília. A produção animal no mundo em transformação: anais. Brasília, DF: SBZ, 2012. 1 CD-ROM.$c2012
520 $aPesquisas efetivas que avaliam a eficiência produtiva de bovino da raça Nelore, variedade mocho, são incipientes. Por isto, este estudo foi realizado com o objetivo de estimar tendências genéticas para as características de dias para se ganhar 160 kg (D160) na fase pré-desmama, e dias para se ganhar 240 kg (D240) na fase pós-desmama, em bovinos da raça Nelore, variedade mocho, criados na região de Mato Grosso. Os componentes de (co)variância e parâmetros genéticos foram estimados por meio do software MTDFREML. As predições médias para tendência genética de D160 e D240 foram -3,29 e -4,48, respectivamente. As estimativas de tendências genéticas evidenciaram a existência de variabilidade suficiente para promover melhoria do rebanho em estudo. Embora estas características não sejam adotadas como critérios de seleção, sua utilização proporcionaria melhoria do rebanho, por meio da seleção de animais mais precoces e com maior velocidade de crescimento.
650 $azebu
653 $aNelore
700 1 $aMAGNABOSCO, C. de U.
700 1 $aLOPES, F. B.
700 1 $aNAKAGWA, A. F.
700 1 $aCASTRO, L. M. de
700 1 $aFERREIRA, L. G. B.
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Embrapa Cerrados (CPAC) |
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