Organization of Genes Conferring Resistance to Anthracnose in Common Bean - Translational Genomics for Crop Breeding: Biotic Stress - page 166

the knowledge at that time about the resis-
tance profile of cultivars MDRK and Kaboon,
the authors proposed that resistance to race 73
in Perry Marrow was conditioned by a third
allele of the Co-1 locus, Co-1 3 . However, cur-
rent results support evidence that the resistance to
race 73 from MDRK and Kaboon is not located in
Pv01 (Campa et al. 2011), and consequently the
results concerning Perry Marrow should be rein-
terpreted. To date, resistance genes from Perry
Marrow had not been mapped in the Co-1 clus-
ter, on linkage group Pv01.

previously reported on Pv03 (Figure 2), in an F2
population obtained from the cross of Jalo Listras
Pretas (R) x Cornell 49242 (S) (Lacanallo et al.
2010). It was assumed that this resistance gene
located in Pv03 was the same locus that con-
fers resistance against races 9, 64, and 65 and
it was named as Co-13 gene, independent from
the previously Co- genes described (Gon¸alves-
Vidigal et al. 2009). The identity of this resis-
tance gene(s), effective against races 9, 64, and
65, should be confirmed by analyzing its co-
segregation with the resistance against race 73,
or by confirming its map position on Pv03 with
marker analyses. Incidentally the same marker
appears to colocalize with a QTL for anthrac-
nose resistance in the B/J mapping population
(Geffroy et al. 2000). Another QTL CL20 condi-
tioning resistance to race 521 had been reported
previously in DOR364/G19833 (D/G) mapping
population (Beebe et al. 1998). It is not possible
to associate the Co-13 gene with these QTL since
different mapping populations were used in these
studies but the resistance sources in the QTL
studies were the Andean parents, Jalo EEP558
and G19833, also known as Chaucha Chuga, a
landrace cultivar from Peru. G19833 provides
resistance to highly virulent races 3481, 3977,
and 3993 from Costa Rica. As has been demon-
strated in other bean genotypes, Jalo Listras Pre-
tas could carry more than one major anthracnose
resistance gene, apart from Co-13 , which could
affect these interpretations.

LinkageGroupPv02

A gene conferring specific resistance to C. linde-
muthianum strains E4 and E42b (showing com-
plete co-segregation) was directly mapped to
the end of Pv02 in the Mesoamerican genotype
BAT93 (Figure 2). This gene was named as Co-u
and located in the vicinity of the I locus (Geffroy
et al. 2008), a complex resistance cluster effec-
tive against potyviruses (Vallejos et al. 2006).
The anthracnose isolates E4 and E42b used to
detect the Co-u gene are unknown as they were
not characterized on the international differen-
tial set. For this reason the presence of the Co-u
gene was not tested in other genotypes. The pos-
sibility that some of the undefined anthracnose
resistance QTL mapped near the I locus on Pv02
(Geffroy et al. 2000), in a relative similar posi-
tion corresponding to Co-u , has never been con-
sidered. Molecular markers located in the chro-
mosome region corresponding to Co-u should
be tested in co-segregation analyses before char-
acterizing a new anthracnose resistance gene to
avoid synonymy between Co- genes.

LinkageGroupPv04

Genes conferring specific resistance to differ-
ent C. lindemuthianum strains were mapped to
the distal portion of Pv04 in bean genotypes
Ms8EO2, Mexico 222, Widusa, BAT93, A493
JaloEEP558, A252, MDRK, Kaboon, and Ouro
Negro (Figure 9.2).
The first anthracnose resistance gene RVI to
be mapped to Pv04 came from the Ms8EO2
breeding

LinkageGroupPv03

A single major gene controls the specific resis-
tance against each one of the races 9, 64, 65,
and 73 in the Brazilian landrace cultivar Jalo
Listras Pretas (Gon¸alves-Vidigal et al. 2009).
The gene effective against race 73 was linked
in coupling at 1.8cM to the marker OPV20 680 ,

line (Adam-Blondon et al. 1994a,

1994b). This gene conferred resistance to

C. lindemuthianum race 21 from Colombia