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Frontana (Steiner et al. 2004). All three QTL led
to a decrease in FHB severity and in DON con-
tent. The 3A QTL from Frontana was less effec-
tive compared to the 3B and 5A QTL from CM-
82036. Lines with the 3BS and 5A QTL alleles
from CM-82036 combined were the most resis-
tant group, which showed reduced DON content
by 78% and reduced FHB rating by 55% com-
pared to the susceptible QTL class. The same
population was used by Miedaner et al. (2008)
to select resistant lines by phenotypic selection
only and to genotype these with SSR markers
linked to the three QTL on 3B, 5A, and 3A
a pos-
teriori
. Among the 135 FHB resistant selections,
121 carried either two or three QTL combined,
and only one selected FHB-resistant line did not
possess any of the SSR marker alleles linked to
the resistance QTL, indicating the expected QTL
contributed to a large extent to resistance perfor-
mance in this selection experiment. A study by
Wilde et al. (2007) compared selection response
between phenotypic selection and marker-based
selection in the same segregating population used
by Miedaner et al. (2006, 2008). A sophisticated
three-step phenotypic selection approach, with-
out any marker evaluation, resulted in the high-
est overall selection gain, but selection gain per
unit time was highest in the marker-based selec-
tion approach, because selection cycles could
be performed much faster. MAS was thus very
efficient in fixing desired QTL resistance alleles
quickly, but phenotypic selection obviously also
gathered unknown or small-effect QTL. Within
each QTL group, variation in FHB resistance was
large. Therefore, even after fixing known QTL by
marker-based selection, phenotypic selection for
unknown or small-effect QTL should be done
in order to select lines with excellent resistance
performance.
Xue et al. (2010) developed and evaluated
NILs for four FHB resistance QTL in the sus-
ceptible cultivar Mianyang 99-323 using SSR
markers flanking these QTL. All four QTL sig-
nificantly improved FHB resistance. The QTL on
3B improved type 2 resistance, the QTL on 4B
and 5A from Wangshuibai improved type 1 resis-
tance, and a QTL from a rather susceptible cul-
tivar Nanda2419 on chromosome 2B enhanced
both types of FHB resistance.
It is an ongoing discussion among breeders
whether one should use non-adapted germplasm
for crossing in an applied cultivar development
program. Usually several rounds of backcross-
ing and rigorous selection are needed to restore
lines with high-yield performance and specific
environmental adaptation plus the desired alle-
les from the non-adapted donor. This is exactly
the situation that faces, for instance, a winter
wheat breeder who aims to incorporate FHB
resistance from an Asian spring wheat donor in
a high-yielding regionally adapted winter wheat
cultivar. In such cases, marker-assisted back-
cross breeding has great potential. Two comple-
mentary projects have been performed recently
by von der Ohe et al. (2010) and Salameh
et al. (2011) to evaluate such an approach. Both
projects were based on the FHB-resistant line
CM-82036 as donor with the well-known QTL
alleles on 3B and 5A. Von der Ohe et al. (2010)
used two German winter wheat cultivars, one
moderately resistant and one highly suscepti-
ble, as recurrent parents for backcrossing and
developed BC
3
-derived lines with both, one, or
no QTL from CM-82036. These BC
3
-derived
lines were tested for FHB resistance in inocu-
lated trials and for agronomic and yield traits in
performance trials across four locations and two
seasons. Salameh et al. (2011) used the same
resistance donor and generated BC
2
-derived
lines in nine different European winter wheat
cultivars. The donor cultivars were chosen to
range from moderately resistant to highly sus-
ceptible. BC
2
-derived sister lines were selected
with both, one, or none of the QTL from CM-
82036. The selected experimental lines were
evaluated for FHB resistance in six inoculated
experiments and a subset of lines for yield and
agronomic performance in three non-inoculated
field trails. These two companion studies yielded
highly congruent results, with minor differences.
Generally progeny lines possessing one or both
QTL from CM-82036 showed improved FHB
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