Phytopathology (2012) 102, 674-682

Nguyen Thi Thanh Nga, Yoshihiro Inoue, Izumi Chuma, Gang-Su Hyon, Kazuma Okada, Trinh Thi Phuong Vy, Motoaki Kusaba and Yukio Tosa (2012)
Identification of a novel locus Rmo2 conditioning resistance in barley to host-specific subgroups of Magnaporthe oryzae
Phytopathology 102 (7), 674-682
Abstract: Barley cultivars show various patterns of resistance against isolates of Magnaporthe oryzae and M. grisea. Genetic mechanisms of the resistance of five representative barley cultivars were examined using a highly susceptible barley cultivar, 'Nigrate', as a common parent of genetic crosses. The resistance of the five cultivars against Setaria, Oryza, Eleusine, and Triticum isolates of M. oryzae was all attributed to a single locus, designated as Rmo2. Nevertheless, the Rmo2 locus in each cultivar was effective against a different range of isolates. Genetic analyses of pathogenicity suggested that each cultivar carries an allele at the Rmo2 locus that recognizes a different range of avirulence genes. One allele, Rmo2.a, corresponded to PWT1, which conditioned the avirulence of Setaria and Oryza isolates on wheat, in a gene-for-gene manner. The other alleles, Rmo2.b, Rmo2.c, and Rmo2.d, corresponded to more than one avirulence gene. On the other hand, the resistance of those cultivars to another species, M. grisea, was conditioned by another locus, designated as Rmo3. These results suggest that Rmo2 is effective against a broad range of blast isolates but is specific to M. oryzae. Molecular mapping revealed that Rmo2 is located on the 7H chromosome.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Yukio Tosa

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Pyricularia oryzae	Barley (Hordeum vulgare)
	Pyricularia grisea	Barley (Hordeum vulgare)