Molecular Plant Pathology (2016) 17, 1154-1159

Y. Wang and M.R. Hajimorad (2016)
Gain of virulence by Soybean mosaic virus on Rsv4-genotype soybeans is associated with a relative fitness loss in a susceptible host
Molecular Plant Pathology 17 (7), 1154-1159
Abstract: 'Gene-for-gene' theory predicts that gain of virulence by an avirulent pathogen on plants expressing resistance (R) genes is associated with fitness loss in susceptible hosts. However, the validity of this prediction has been studied in only a few plant viral pathosystems. In this study, the Soybean mosaic virus (SMV)–Rsv4 pathosystem was exploited to test this prediction. In Rsv4-genotype soybeans, P3 of avirulent SMV strains provokes an as yet uncharacterized resistance mechanism that restricts the invading virus to the inoculated leaves. A single amino acid substitution in P3 functionally converts an avirulent to a virulent strain, suggesting that the genetic composition of P3 plays a crucial role in virulence on Rsv4-genotype soybeans. In this study, we examined the impact of gain of virulence mutation(s) on the fitness of virulent variants derived from three avirulent SMV strains in a soybean genotype lacking the Rsv4 gene. Our data demonstrate that gain of virulence mutation(s) by all avirulent viruses on Rsv4-genotype soybean is associated with a relative fitness loss in a susceptible host. The implications of this finding on the durable deployment of the Rsv4 gene in soybean are discussed.
(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): M. Reza Hajimorad

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.
	Soybean mosaic virus	Soybean (Glycine max)