Data/hora: 01/06/2024 22:43:22

Biblioteca(s): | Embrapa Gado de Corte.
Data corrente: | 10/07/1998
Data da última atualização: | 10/07/1998
Autoria: | CHAKRABORTY, S.; PERROT, R.; CHARCHAR, M. J. D`A.; FERNANDES, C. D.; KELEMU, S.
Afiliação: | CSIRO. Tropical Agriculture (Queensland, Australia).
Título: | Biodiversity, epidemiology and virulence of Colletotrichum gloeosporioides. II. Genetic and pathogenic diversity in isolates of Colletotrichum gloeosporioides from eight species of Stylosanthes.
Ano de publicação: | 1997
Fonte/Imprenta: | Tropical Grasslands, Brisbane, v.31, n.5, p.393-401, Nov. 1997.
Idioma: | Inglês
Notas: | CNPGC.
Conteúdo: | This work provides information on genetic and pathogenic variation in isolates of Collectotrichum gloeosporioides which cause anthracnose disease in many species of the tropical pasture legume, Stylosanthes. Isolates collected from species other than S. guianensis mainly from the centre of host-pathogen diversity in South America were studied using Random Amplified Polymorphic DNA (RAPD) markers and differential virulence on a set of host differentials. A phenetic analysis of 90 isolates using RAPD markers showed a wide genetic diversity in the pathogen population. The genetic variation in the Australian population was very limited compared with that at the centre of diversity. A similar situation was detected for pathogenic variation in 69 isolates from Brazil, many of which showed higher severity on Australian cultivars and accessions. These include accessions and cultivars which are highly resistant to the Australian races of the pathogen. However, pathogenic diversity in the Brazilian population of C. gloeosporioides was only partly characterised due to the limited number of host differentials used in this study. Attention needs to focus on the development and use of a more extensive range of host differentials. There was no strong relationship between genetic and virulence markers. Consequently, pathogenicity tests need to be conducted to answer the more practical questions such as the risk to current commercial cultivars from markers will damaging races. Use of molecular be useful to understand better the movement of pathogen populations between geographically isolated regions. Isolates used in this work have come mainly from regions where S. capitata and S. guianensis are endemic. Further isolate sampling from regions representing the native range of commercial species such as S. scabra and S. hamata will be necessary for a more comprehensive understating of this diversity.
Palavras-Chave: | Anthracnosis; Brasil; Colletotricum gloeosporioides.
Thesagro: | Antracnose; Epidemiologia; Estilosante; Marcador Genético; Patogenicidade; Stylosanthes Guianensis; Stylosanthes Macrocephala; Stylosanthes Scabra; Variação Genética.
Thesaurus Nal: | Australia; Brazil; Colombia; epidemiology; genetic markers; genetic variation; pathogenicity; Stylosanthes capitata; Stylosanthes hamata.
Categoria do assunto: | --
Registro original: | Embrapa Gado de Corte (CNPGC)
Exemplares: | CNPGC - (2423-1) - UPC - AP - -- - 633.205 -  - 633.205 - DIS