Selection of DNA markers closely linked to the resistance gene <i>rym7t</i> against Barley yellow mosaic disease

Abstract

This study was conducted to select a DNA marker linked to the new recessive resistance gene rym7t, which is derived from 'Tokushima mochihadaka' and confers resistance to Barley yellow mosaic virus (BaYMV) strains I, II and III. A genetic linkage map neighboring rym7t was constructed using doubled haploid lines derived from a cross between the resistant parent 'DH21-73,' which includes rym7t, and susceptible parent 'Haruna Nijo'. Two SSR markers, Bmac0031 and Bamc0167 were selected, adjacent to each side of the rym7t locus. The genotype of the two SSR markers corresponded well to the phenotype of BaYMV resistance. The field test of Barley yellow mosaic disease (virus strain I) resistance of F 2 individuals derived from a cross between the susceptible parent 'New Golden' and resistant parent 'DH42-84,' which includes rym7t, showed that the correspondence rates between phenotypes of BaYMV resistance and genotypes with Bmac0031 and Bamc0167 were 98.6% and 98.8%, respectively. In the case of correspondence between the two markers' genotypes, they corresponded exactly with the phenotype of BaYMV resistance of F 2 individuals. The two SSR markers were co-dominant, so both could clearly identify susceptible plants with heterozygous rym7t. The two SSR markers could be useful for marker-assisted selection of resistant lines including rym7t.

Screening of stable resistant accessions and identification of resistance loci to Barley yellow mosaic virus disease

“…rym2 and rym7t mapped at the interval position from 213 Mbp to 369 Mbp on chromosome 7H showed resistance to BaYMV disease ( Gotz & Friedt, 1993 ; Takata et al, 2012 ). In this study, SNP0024 at a position 18 Mb from the start of chromosome 7H was significantly associated with BaYMV disease.…”

“…In addition to the cloned eIF4E and PDIL5-1 resistance alleles, rym7 (resistance against BaMMV) ( Yang et al, 2013 ), Rym16 Hb (from Hordeum bulbosum , resistance against all strains) ( Ruge-Wehling et al, 2006 ; Johnston et al, 2015 ), Rym17 (from barley landrace, resistance against BaYMV) ( Kai et al, 2012 ) and Rym14 Hb (from Hordeum bulbosum , resistance against all strains) ( Pidon et al, 2020 ) have been precisely mapped to small regions on chromosomes 1H, 2H, 3H, and 6H, respectively. The remaining ten BaYMV disease resistance genes rym2 (resistance against several strains of the two viruses) ( Gotz & Friedt, 1993 ), rym3 (resistance against several BaYMV strains) ( Werner et al, 2003b ), rym7t (resistance against several BaYMV strains) ( Takata et al, 2012 ), rym8 (resistance against several strains of the two viruses) ( Bauer et al, 1997 ), rym9 (resistance against several BaMMV strains) ( Werner, Friedt & Ordon, 2005 ), rym12 (resistance against several strains of the two viruses) ( Gotz & Friedt, 1993 ), rym13 (resistance against several strains of the two viruses) ( Werner et al, 2003a ), rym15 (resistance against BaMMV) ( Le Gouis et al, 2004 ), rym18 (resistance against BaYMV) ( Kai et al, 2012 ), and Un-designated (resistance against BaYMV) ( Saeki et al, 1999 ) have only been preliminarily mapped. The stacking of several known disease resistance genes by breeding can improve the resistance of barley accessions to BaYMV disease ( Yang et al, 2017 ; Jiang et al, 2020 ).…”

Identification of novel QTL contributing to barley yellow mosaic resistance in wild barley (Hordeum vulgare spp. spontaneum)

“…In addition to cloned eIF4E and PDIL5-1 , rym7 [ 26 ], Rym16 HB [ 27 , 28 ], Rym17 [ 29 ] and Rym14 HB [ 4 ] have been fine-mapped to a small region on chromosome 1H, 2H, 3H, and 6H, respectively. The remaining 10 BYMD-resistant genes rym8 [ 30 ], rym9 [ 31 ], rym12 [ 32 ], rym13 [ 33 ], rym18 [ 29 ], rym3 [ 34 ], Un-designated [ 35 ], rym15 [ 36 ], rym2 [ 32 ] and rym7t [ 37 ] have been preliminarily mapped.…”