Data/hora: 14/06/2024 09:28:46

Biblioteca(s): | Epagri-Sede.
Data corrente: | 15/04/2016
Data da última atualização: | 15/04/2016
Autoria: | ARAUJO, L.; SOARES, J. M.; FILIPPI, M. C. C.; RODRIGUES, F. Á.
Título: | Cytological aspects of incompatible and compatible interactions between rice, wheat and the blast pathogen Pyricularia oryzae.
Ano de publicação: | 2016
Fonte/Imprenta: | Scientia Agricola, Piracicapa - USP/ESALQ - Scientia Agricola, v. 73, n. 2, p. 177-183, 2016.
Idioma: | Inglês

Conteúdo:

Blast, caused by the fungus Pyricularia oryzae, is an important disease affecting
rice and wheat yield worldwide. This study investigated the cytological aspects of incompatible
(non-host resistance) and compatible (host resistance) rice- (R_Po) and wheat- (W_Po) Pyricularia
oryzae isolate interactions. Inoculations of rice and wheat with the R_Po and W_Po isolates of
P. oryzae, respectively, were expected to be compatible interactions (host resistance), whereas
inoculations of rice and wheat with the W_Po and R_Po isolates of P. oryzae, respectively, were
considered to be incompatible interactions (non-host resistance). For the compatible interactions
(rice-R_Po and wheat-W_Po), fungal hyphae penetrated and colonized the epidermal cells
and also invaded many neighboring cells. By contrast, in the case of the incompatible interactions
(rice-W_Po and wheat-R_Po), fungal hyphae were not able to penetrate nor colonize the
epidermal cells, but when penetration did occur, the hyphae were restricted to the first-invaded
epidermal cell. The frequency of appressorial sites exhibiting infection hyphae within the epidermal
cell underlying an appressorium was greater in the case of the compatible interactions. By
contrast, unsuccessful penetrations with cytoplasmic granulation occurred with high frequency
in the incompatible wheat-R_Po and rice-W_Po interactions and the number of necrotic epidermal
cells underlying the appressorium was low for the rice-W_Po interaction as well as for the
wheat- R_Po interaction, where no symptoms of necrosis were exhibited. However, the opposite
was observed for the compatible interactions. The present study presents cytological features
associated with incompatible and compatible rice- and wheat-P. oryzae interactions that may
be useful to studies involving variability, coevolution, diagnosis, and regulation of quarantine or
even in a rice or wheat breeding program whose aim is to transfer genes involved in non-host
resistance to host resistance due to similarities in downstream mechanisms.

Palavras-Chave: | blast disease; host resistance; Magnaporthe oryzae; Oryza sativa; Triticum aestivum L.
Categoria do assunto: | X Pesquisa, Tecnologia e Engenharia
URL: | http://intranetdoc.epagri.sc.gov.br/producao_tecnico_cientifica/DOC_37616.pdf
Registro original: | Epagri-Sede (Epagri-Sede)
Exemplares: | Epagri-Sede - (100013-1) - UPC - AP - DD -  -  -  - DIS