Virus Resistance in Barley - Translational Genomics for Crop Breeding: Biotic Stress - page 67

List of mapped major virus resistance genes in barley (modified and updated according to Ordon et al. 2009).

Table 5.1.

Resistance
gene

Chromsomal
location Reference(s)

Barley stripe mosaic virus (BSMV)
Rsm 7HS Edwards and Steffenson 1996

Barley yellow dwarf virus (BYDV)
Ryd2 3HL Collins et al. 1996; Paltridge et al. 1998; Ford et al. 1998
Ryd3 6H Niks et al. 2004
Ryd4 Hb 3HL Scholz et al. 2009
Barley yellow mosaic virus (BaYMV), Barley mild mosaic virus (BaMMV)
rym1

4HL Okada et al. 2004

rym3 5HS Saeki et al. 1999; Werner et al. 2003a

rym4 3HL Graner and Bauer 1993; Ordon et al. 1995; Weyen et al. 1996; Stein et al.

2005; Kanyuka et al. 2005; Werner et al. 2005; Stracke et al. 2007; Tyrka et al.
2008; Sedlacek et al. 2010

rym5 3HL Graner et al. 1999b; Pellio et al. 2005; Stein et al. 2005; Kanyuka et al. 2005;

Stracke et al. 2007; Tyrka et al. 2008; Sedlacek et al. 2010

rym6 3HL Kanyuka et al. 2005

rym7 1HS Graner et al. 1999a

rym8 4HL Bauer et al. 1997

rym9 4HL Bauer et al. 1997; Werner et al. 2005; Werner et al. 2000

rym10 3HL Graner et al. 1995

rym11 4HL Bauer et al. 1997; Nissan-Azzouz et al. 2005; Werner et al. 2005

rym12 4HL Graner et al. 1996

rym13 4HL Werner et al. 2003b; Humbroich et al. 2010

Rym14 Hb

6HS Ruge et al. 2003

rym15 6H Le Gouis et al. 2004

Rym16 Hb 2HL Ruge-Wehling et al. 2006

Rym17 3HS Kai et al. 2012

rym18 4HL Kai et al. 2012

Beside prolonging the usability of resistance
genes, pyramiding may also result in a higher
level of resistance as has been recently shown
for BYDV (Riedel et al. 2011). In this study,
Ryd2 , Ryd3 and the QTL located on chromo-
some 2H derived from cv. “Post” were combined
using DH-Lines and molecular markers, and it
turned out that those lines carrying a combina-
tion of Ryd2 and Ryd3 showed a significantly
reduced virus titre; in other words, a combination
of these loci has resulted in quantitative resis-
tance to BYDV in contrast to tolerance encoded
by these loci alone.

the structure and function of virus resistance
genes in barley and on the other hand to facili-
tate directed allele-based selection procedures.
To isolate such resistance genes in the com-
plex genome of barley, a map-based cloning
approach (cf. Stein and Graner 2004) turned
out to be effective to isolate the Rym4/Rym5
locus located on chromosome 3H and confer-
ring resistance to BaMMV/BaYMV (Stein et al.
2005). For this purpose a high-resolution map-
ping population based on about 8,000 meioses
was constructed and marker-based saturation
was conducted employing 932 Pst I + 2/ Mse I + 3,

2,048 Eco RI 3 AFLP primer combi-

nations, and 1,200 RAPD primer resulting in
11 markers within the target interval (Pellio
et al. 2005). In the end, based on the closest
marker, a BAC-contig was identified (Wicker
et al. 2005) carrying the translation initiation

+ 3/ Mse I +

Isolation of Virus Resistance Genes
in Barley

Isolation of resistance genes is of special inter-
est, on the one hand, to get information on