Allelism among Genes for Resistance to Soybean Mosaic Virus in Strain‐Differential Soybean Cultivars

Abstract

Five soybean [Glycine max (L.) Merr.] cultivars that have been used to differentiate strain groups of soybean mosaic virus (SMV) were studied to determine the allelic relationships among genes conditioning reaction to SMV. The cultivars PI 96983, ‘Ogden’, ‘York’, ‘Marshall’, and ‘Kwanggyo’ (PI 406710) are each known to have single dominant gene conditioning resistance to SMV. These parents were crossed in all possible combinations with each other and with a susceptible cultivar. The crosses were evaluated in the F2 and with F2‐derived F3 lines in the field and in the greenhouse for reaction to inoculation with the G1 strain of SMV (SMV‐G1). Results confirm that each of the resistant cultivars has a single dominant gene for resistance to SMV‐G1, but that dominance is sometimes incomplete. The lack of segregation for susceptibility in F2 and F3 progenies from the resistant ✕ resistant crosses indicates a high probability that the resistance genes in these cultivars are alleles at a common locus. Gene symbols Rsvy1, Rsvm1 and Rsvk1 are proposed for the resistance alleles in York, Marshall, and Kwanggyo, respectively. The systemic necrosis reaction that sometimes occurs following SMV‐G1 inoculation of segregating populations is highly associated with plants heterozygous for the resistance gene, but may be influenced by environment and genetic background.

Interaction between two strains ofSoybean mosaic virusin soybean

“…PI 96983 was identified as carrying a dominant gene Rsv1 conferring resistance to G1 and a necrotic reaction to G7 (Chen et al 2001(Chen et al , 2002. 'York' was identified to have a single gene Rsv1-y for resistance to G1 but susceptibility to G7 (Chen et al 1991. 'Prolina' and 'Dillon' had the same SMV reaction patterns (resistant to G1 but susceptible to G7) as 'York' and were postulated to carry the same gene (Rsv1-y) that was derived from the ancestor cultivar 'Arksoy' (Zheng et al 2005).…”

The evolution of soybean mosaic virus: An updated analysis by obtaining 18 new genomic sequences of Chinese strains/isolates

“…The four tested Chinese SMV strains/isolates were incapable of infecting 'PI96983', which possesses a resistant locus, Rsv1 (Chen et al, 1991). The virulence determinants on the Rsv1-genotype soybeans have been mapped to HC-Pro and P3, and the gain of virulence by an avirulent SMV requires at least three simultaneous amino acid substitutions: either two in HC-Pro and one in P3, or two in P3 and one in HC-Pro Hajimorad et al, 2008Hajimorad et al, , 2011.…”

Detection, Understanding and Controlof Soybean Mosaic Virus

“…It was initially named Rsv and found in PI96983 soybean (Kiihl and Hartwig, 1979) and later renamed Rsv1 (Chen et al, 1991). Subsequent studies on soybean cultivars resistant to SMV revealed additional eight different Rsv1 alleles, from cultivars Ogden, York, Marshall, Kwanggyo, 'Raiden', 'Suweon 97', LR1 and PI507389, respectively (Kiihl and Hartwig, 1979;Buss et al, 1997;Buzzell and Tu, 1989;Chen et al, 1991Chen et al, , 1993Chen et al, , 1994Chen et al, , 2001Chen et al, , 2002Ma et al, 1995;Zheng et al, 2005). The responses of soybeans carrying these Rsv1 alleles to different SMV strains are diverse, ranging from extreme resistance and necrosis to mosaic symptoms.…”